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INSECTS: FRIENDS OR FOES?
An inaugural lecture delivered
at the University of Ibadan
on Thursday, 04 June, 2015
By
FRANCIS KOLAWOLE EWETE
Professorof Entomology,
Faculty of Agriculture and Forestry,
University of Ibadan,
Ibadan, Nigeria.
UNIVERSITY OF IBADAN
UNIVERSITY OF IBADAN LIBRARY
, '
Ibadan University Press
Publishing House
University of Ibadan
Ibadan, Nigeria.
© University of Ibadan, 2015
Ibadan, Nigeria
First Published 2015
All Rights Reserved
ISBN: 978 - 978 - 8456 - 81- 0
'Printed by: Ibadan University Printery
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The Vice-Chancellor, Deputy Vice-Chancellor (Administra-
tion), Deputy Vice-Chancellor (Academic), The Registrar and
other Principal Officers, Provost of the College of Medicine,
Dean of the Faculty of Faculty of Agriculture and Forestry,
Deans of other Faculties and Postgraduate School, Dean of
Students, Distinguished Ladies and Gentlemen.
Introduction
I sincerely thank the University of Ibadan for giving me this
opportunity to deliver an inaugural lecture on behalf of the
Faculty of, Agriculture and Forestry at the twilight of
disengaging from the University. I must thank the Dean of
" my Faculty for nominating me to deliver this lecture on
behalf of the Faculty as well as my Head of Department for
ensuring that the lecture is delivered. Were it not for the
extension of retirement age to 70 years, I would have missed
this golden opportunity to stand before this audience, since I
would have retired from the University in 2014. It has taken
me 15 years after my elevation to the grade of Professor
before this opportunity arose. '
This is the fourth in the series of inaugural lectures for the
-2014/2015 academic session and also the 41st from the
Faculty of Agriculture and Forestry since its inception in
1949. It is the 10th inaugural lecture from the Department of
Crop Protection arid Environmental Biology, the 8th and 9th
lectures having been delivered by Professors Bamidele
Fawole and Babatunde Ikotun, respectively and the three of
us were 1972 graduates of this Faculty.
Mr. Vice-Chancellor, I must hasten to say that this is not
by design. May I also re-iterate that this is the 4th inaugural
lecture from the Entomology Unit of the Department, the first
having been delivered by our erudite scholar and",teacher,
Professor T. Ajibola Taylor of blessed memory, entitled
"Insects and Our Environment", in 1974. This was followed
by that of another teacher of ours, Professor Anthony
Youdeowei, also titled, "Insects and Nigerians: The Struggle
for Existence", in 1977, and the third by Professor J.A.
Odebiyi titled, "Understanding and Exploitation of Balance of
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Nature in Insect Pest Management", in'2004. My interest was
aroused in Entomology by Late Professor T. Ajibola Taylor
shortly after my admission into the one year Postgraduate"
Diploma Programme in Crop Protection, newly introduced in
the then Department of Agricultural Biology during the
1973/74 session. There was a problem of obtaining good
quality seeds for planting purpose in an okra breeding project
initiated by the Late Professor H.R. Chheda in the
Department of Agronomy. Here was I, just admitted into the
diploma course and assigned the responsibility of tackling the
problem under the joint supervision of Professors Taylor and
Chheda.
It is a well known fact that prior to being harvested for
seed production, dry okra fruits are heavily infested by the
seed bugs, Dysdercus (superstitiosus) voelkeri and Oxyca-
renus gossypinus (fig. 1).
Fig. 1: A colony of seed bugs Dysdercus (superstitiosus) voelkeri and
Oxycarenus gossypinus.
Please permit me to say here that the Late Professor Chheda
and I had a good working relationship, having supervised my
final year project in 1972 in the Department of Agronomy
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where I obtained my B.Sc. Honours (Agriculture) in Crop
Science. After completing the final year project with him, he
called me into his office one day and said: "Evete" (The
Indians would normally pronounce the letter OW' as 'V' and
vice versa), you just include my name as one of your referees
whenever you are applying to anywhere". Before the com-
pletion of the Postgraduate Diploma course, the preliminary
results that I presented fascinated both of them. One day I
was summoned to Professor Taylor's office and both of them
asked me if I was ready to proceed to the M.Sc. (Agric.)
degree if offered a scholarship. Of course I replied positively.
Within one week, my letters of admission and award of
Rockefeller Foundation Scholarship were ready. The rest is
history and I now stand before you as an entomologist.
What is Entomology?
This is the branch of science that deals with the study of
insects whether in the pure or applied form.
What are Insects?
Virtually everyone in this audience lives with one form of
insects be it flies, mosquitoes, cockroaches, ants, termites,
butterflies, et cetera, at home, in the office, or restaurant.
Therefore we can all recognize a living creature known as
insect. Technically however, insects are invertebrates
(animals without backbone) in the Phylum Arthropoda which
is the largest member in the Animal Kingdom. The
classification of the Phylum and the Class Insecta to which all
insects belong had been well enunciated by my three worthy
predecessors and teachers in their inaugural lectures. This
therefore spares me the time and energy to dissipate on this
aspect. But basically for any organism to be grouped into the
Class Insecta, the body must be divided into three distinct
parts - head, thorax, and abdomen. The head bears a pair of
compound eyes for sight, as well as filaments (antennae) for
feeling the environment. The thorax is three-segmented,
namely: prothorax, mesothorax, and metathorax with a pair of
legs attached to each thoracic segment. Consequently, insects
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possess six (6) legs and hence are referred to as
HEXAPODA.
Mr. Vice-Chancellor sir, I know no other animal that
possesses six legs. The closest relatives, ticks and mites,
possess eight (8) legs. Other animals possess two (2) legs, as
in birds, and four (4) legs in toads, lizards, pets, primates and
ungulates.
Insects are the most biologically successful animals in the
Animal Kingdom. For instance, their small size accounts for
their extremely low food requirement and the colonization of
small niches in their thousands. In addition, they are highly
adaptive to. extreme living conditions of hotness and coldness
ranging from the equator to the arctic and subarctic regions of
the earth, being poikilothermic (cold-blooded). Besides,
insects are highly fecund (producing many offsprings) and
exhibit different types of reproduction, namely: oviparous,
-ovoviviparous, viviparous, polyembryony, paedogenesis,
parthenogenesis and hermaphroditism.
Oviparous reproduction is one in which eggs are laid and
hatch into young ones. Majority of insects practice this form
of reproduction. In ovoviviparous reproduction, eggs are
retained within the body of the insect until they hatch as they
are being laid. This occurs in most aphids and some flies.
Viviparous reproduction is one in which embryos develop in
the body cavity and when fully mature they are brought forth
alive as found in man and other mammals. The tsetse fly
. (Glossina spp.) that transmits sleeping sickness in cattle and
man, is a good example. Polyembryony is one in which many
offsprings emerge from a single egg. This is particularly
common among endoparasitic insects that develop within the
tissue of their host and are hence regarded as natural enemies.
Paedogenesis is a form of reproduction in which immature
stages (larvae) mature their ovaries very fast and begin egg-
laying before attaining the adult stage, as it occurs in some
gall midges. Parthenogenesis is a type of reproduction in
which young ones develop from unfertilized eggs. Even
within this type, there are three different forms based on the
sex of the offsprings; it is thelytoky if the offsprings are
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exclusively female; arrhenotoky if exclusively male; and
amphitoky if both male and female offsprings are produced.
Hermaphroditism is reproduction in which both spermatozoa
and eggs are produced by the same insect and these are
fertilized by the spermatozoa and develop into offsprings,
while the unfertilized eggs develop into males.
Mr. Vice-Chancellor sir, I am neither attempting to bog
down the audience with these entomological jargons nor
make everyone an entomologist within this one-hour lecture,
but I am only exposing the complexity of these organisms
known as insects. They are also the only known lower
organisms that possess wings to conquer the challenges of
aerodynamics by flying to safety in times of danger or for any
other exploratory activities to enhance their living. This is
particularly true of the Monarch butterfly (Danaus sp) in
Canada that flies southwards to Mexico it].late summer where
they mate, deposit eggs and all die. The newly emerged adults
(tenerals) now fly northwards to Canada in spring.
Rote of Insects toMankind
Mr. Vice-Chancellor sir, having highlighted what insects are,
and that they are the most successful animal group on earth,
one can now proceed with the role of insects to mankind. This
will help us to discern those insects that are beneficial and/or
harmful to man and his agricultural produce.
The Beneficial Insects
These are insects that contribute positively to the welfare
and/or well-being of man in a number of ways through their
activities in the ecosystem.
The Pollinators
These are groups of insects that visit flowers of cultivated
crops and other plants to collect nectar and pollen grains for
their food and in the manufacture of other useful commodities
for man's use. Notable among these are the honey bees as
well as butterflies, moths, wasps, flies and beetles. In the
process of the visit, they inadvertently transfer pollen grains
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to the stigma of the flowers and hence effect pollination. This
has resulted in fruit and seed production on an unimaginable
scale leading to increased agricultural productivity and
satisfying the food needs of man.
Manufacturers of Useful Commodities
A number of useful products are being manufactured by
different insect species across various orders. These include.
the following:
(i) Honey, Propolis and Bees Wax
These are products manufactured by the honey bee,
Apis mellifera (Hymenoptera: Apidae). Honey is
useful as a food source as well as for the medical
treatment of woundslburns by preventing bacterial
infection. The bees wax from hives is used in the
production of candle.
Bee-keeping is a big business world-wide and I
must confess here that our Department keys well into
such a venture through funding by the University
Management, to generate funds for this University as
pari of the Internally Generated Revenue (IGR).
(ii) Wax
This is a commodity from the nests of wasps
(Hymenoptera: Vespidae) used in the manufacture of
candle and polish.
(iii) Shellac
.This is a commodity obtained from scale insects
(Hemiptera: Coccidae) and used in the making of
paints as well as gums for sticking motor engine
gaskets together.
(iv) Cocoon (fig. 2)
This is a woven silken material produced by the
larvae of lepidopterous insects such as Anaphe
venata when about to pupate. The harvested cocoons
are unwounded into yams which are used in
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sericulture for making cloths such as silk cloth, and
traditional Yoruba "aso oke (sanyan)". This is
another commercial enterprise which individuals and
corporate bodies can engage in for revenue
generation. An attempt at this venture by the
Department ended abruptly owing to abscondment by
a Ph.D. student placedon the project.
Fig. 2: A woven silken material from the larvae of Anaphe venata.
Natural Enemies
These are groups of insects that kill other insects which infest
our agricultural products. They are the predators and parasites
that feed on harmful insects on our crops. Predators are
generally bigger than their prey, while parasites are smaller
than their hosts. The predatory insects include those in figures
3,4 and 5.
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Fig. 3: Praying mantis - Mantis religiosa.
Fig. 4: Assasin bugs - Pseudophonoctonus-formosus.
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Fig. 5: Rhinoeoris bieolor.
Others are: Ladybird beetle - Cheilomenes lunata, Lacewings
(Order: Neuroptera: Chrysopidae), Dragon flies (Order:
Odonata).
In the coccinelid beetle (Ladybird), assassin bugs and
Mantis, both adult and larvae or nymphs kill and feed on their
prey, while only larvae are involved in Neuroptera and
Odonata.
The parasitic insects, especially the endoparasitoids, are
found mainly in two insect orders; Diptera and Hymenoptera.
These include:
Tachinid flies (Diptera: Tachinidae)
Braconid Wasps (Hymenoptera: Braconidae) (fig. 6)
Cha1cidWasps (Hymenoptera: Chalcidae)
Ichneumonid Wasps (Hymenoptera: Ichneumonidae)
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Fig. 6: The braconid wasps (hymenoptera: braconidae).
Braconid wasps use their slender ovipositor to deposit an egg,
each within the tissue of their hosts later hatching into a
young larva, continues to feed within the host tissue and
eventually bursts open the host tissue to pupate outside and
with the adult later emerging. In this way, the host is killed. It
therefore follows that these groups of entomophagous insects
that help in reducing insect pest populations to sub-economic
levels can be manipulated for the control of major insect pests
through a control strategy called Biological Control. Prof.
J.A. Odebiyi enunciated this in his 2004 Inaugurall..ecture as
part of the thrust of his work in this University in the control
of cassava and mango mealybugs.
Soil Nutrient Enrichment
Certain soil-dwelling or subterranean insects such as the
Springtails (Collembola) as well as dung beetle enrich the soil
by degrading plant residue and/or mixing faeces with soil to
increase the soil organic matter content which enhances crop
growth and subsequent yield increases. This is of great
advantage to farmers who most often practise zero-tillage.
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Edible Insects
The larvae of some lepidopterans (butterflies, moths) as well
as the larvae and adults of some beetles (palm weevil, 'palm
beetle) (figs. 7, Sa & 8b), the winged termites and queen
termite, adult crickets, and some grasshoppers (locusts,
variegated grasshoppers), are good sources of protein and fat.
For instance, travellers along the highways of Delta, Bayelsa
States and the creeks of Ondo State witness the hawking of
roasted or fried larvae of the palm beetle and the palm weevil,
being sold along with 'papa garri' (a crumbed cassava meal).
These supply cholesterol-free oils/fats and protein which aid
human diet.
Fig. 7: Some edible insects.
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Fig. 8a: Palm beetle. Fig. 8b: Palm beetle larvae.
Insects as Aesthetics
Indeed insects are very beautiful. The combination of colour
display by butterflies, moths as well as other insects such as
the beetles, dragonflies, and grasshoppers depict the work of
nature. A mounted insect display in the home adds colour and
serenity to the immediate environment. There is an insect
species given the scientific name Cynthia spp, its common
name being 'Painted Lady' and this is without prejudice to
ladies who bear Cynthia in this audience.
Mr. Vice-Chancellor sir, you know very well that ladies
can be very beautiful when they make up but NOT painted.
Artists also use insects as designs in the textile industry and
they are also used as pendants to add value to dressing.
Insect as Source of Wisdom
According to the Holy Bible in Proverbs 6: 6-8, 1 quote:
"You idler, go to the ant, watch her ways and be wise. She
has no master, no steward or overseer. She secures food in
summer and stores up provisions during harvest time".
In a similar manner, man can learn from termites. The
termites construct their mounds or termitaria gradually and
reside in them. Thus the saying in Yoruba, Were ni ikan
nmole (termites build gradually). They engage in division of
labour using their different forms or castes such .as the
soldiers, workers, winged reproductives and the queen
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normally housed in a 'royal chamber' with each performing
specific functions for the colony. The soldiers are strictly for
defense of the colony in case of any intruder or invasion by
unwanted visitors. I dare say that no living creature (not even
snakes) can reside in an active termitarium. In fact, the
soldiers are the first to rush out to resist any aggression. The
queen is for laying eggs and production of offsprings and
population build-up. The queen is at the core of the
termitarium heavily defended. This semi-fortress can be
likened to the British Monarchy System of government in
which the Queen is the ceremonial head and heavily defended
by British troops. The workers reconstruct damaged termi-
tarium and forage for food and feed the young ones as well as
the queen that is sedentary in its royal chamber (fig. 9). The
winged termites fly out to colonise a new area in case of
population explosion.
Fig. 9: The royal chamber of a termitarium and a queen termite.
Insects as Weapons of War or Biological Warfare
There are instances in which insects can be deployed for
errands to punish stubborn people or to show resentment
against bad behaviour. According to the Holy Bible, out of
the ten (10) plagues Yahweh unleashed to torment Pharaoh
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for failure to release the Israelites from bondage, three (3)
were of insect origin. These were the use of mosquitoes in the
3rd plague in Exodus 8: 13-14. The 4th plague was the use of
horseflies in. Exodus 8: 20, 1 quote: ."Yahweh did this and
dense swarms of horseflies invaded Pharaoh's house and the
houses of all his people and devastated the whole country".
The 8thplague was the use of locusts in Exodus 10: 13-15,
and 1 quote:
"So Moses stretched out his staff over the land of
Egypt. All that day and night Yahweh brought an
.east wind over the land and in the morning the
east wind brought locusts. They devoured all the
vegetation . . . . . . . . .. . .. . . . . . . . . . . .. and nothing
green remained in the land of
Egypt".
Also, in Nigeria during the First Republic and according
to an eye witness account by my very good friend, Professor
S.O. Bada (then Mr. Bada), while the then Premier of the Old
Western Region, Chief S.L. Akintola of the Nigerian National
Democratic Party (NNDP) was on a campaign tour in 1965 at
Ikare-Akoko; and as he mounted the podium, a swarm of bees
besieged the campaign arena followed by a heavy thunder-
storm. Everybody scampered for safety and so ended the
campaign. The punitive measure might not be unconnected
with the disagreement between Chief S.L. Akintola (the
Premier of Western Region) and Kabiyesi Oba Amusa
Momoh III, the then Olukare of Ikareland. Chief Akintola had
earlier reduced the salary of Oba Momoh to a penny (one
kobo) per annum for supporting the then Ooni of Ife (Oba
Adesoji Aderemi) and the Action Group (AG) Party. His
counterpart, Oba Samuel Akinsanya, the then Odemo of
Ishara-Remo in the present Ogun State also had his salary
reduced to a penny per annum by Chief Akintola for the same
offence.
The Harmful Insects
This is a group of insects that feed on plants/plant products,
animals/animal products and man, resulting in damage and/or
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death. This covers a, vast area of entomology which may be
compartmentalized into the following:
(i) Agricultural entomology
(ii) Forest entomology
(iii) Veterinary entomology
(iv) Medical entomology
(v) Forensic entomology
Agricultural entomology covers aspects of insects infesting
and causing damage to cultivated crops and reared animals in
the field or in storage. Forest entomology is the study of
insects infesting tree species in the forest as well as household
forest products. I must state here that our Department has
been responsible for the teaching of this course in the
Department of Forest Resources Management right from its
inception in 1963 as a department in this Faculty. In some
developed parts of the world, such has grown into. a full-
fletched department; especially at the University of British
Columbia, Vancouver, Canada where I was a visiting scientist
during my Sabbatical Leave at the University of Ottawa,
Ottawa, Ontario, Canada in 1993. Veterinary entomology is
the study of insects in relation to transmission of livestock
diseases such as trypanosomiasis (sleeping sickness) by tsetse
fly (Glossina palpalis, G.. morsitans) as well as, myasis
transmitted by Cochliomya hominivorax in cattle.
Medical entomology deals with insect vectors trans-
mitting diseases such as yellow fever, malaria fever, dengue
fever, typhoid fever: dysentery, cholera, diarrhoea, river
blindness (onchocerciasis), sleeping sickness (trypa-
nosomiasis) and their vector control. While Anopheles sp
transmits malaria parasite, Culex sp. transmits yellow fever
and dengue fever. Onchocerciasis is transmitted by the black
fly, Simulium sp. and cholera, dysentery, and diarrhoea are
transmitted by the housefly, Musca domestica. Forensic
entomology is the scientific discipline that helps interpret
information on homicide cases using insects -as 'silent
witnesses' in order to provide evidence or clue which cannot
be obtained from normal classic pathology (Usua 2004).
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.bIel1.,.Ger'insecets,pecially blowflies, can be used in medico-
legal investigations since they are the first arthropods to visit
a corpse within a few hours following death (Catts and Goff
1992).
Mr. Vice-Chancellor, sir, kindly permit me to refer to a
classic unfortunate incident in Tafawa Balewa (Postgraduate)
Hall in 1998 when I was the Hall Warden. A student had died
overnight in his room in B Block with the door locked. It was
the ,swann of blowflies hovering on die window net and door
m!lfellJI2~r1oUr toW21.J.ng morrn.ng that provi'ded m. r1o: rmatio• n that
rrr 2 Emmemnnzs uwas arrn.s. hivou 2·~rJ. s In t e room.
Beoh, ld on breaking the
~ "i~B8n,me student was already stone dead. The swarm of
.~Rs/rfJX-ffl~f;s forensic indicator of corpses (Greenberg 1991).
ru, ni 5 11. . ,
i}~ y,tto Agncultural Entomology
W~tSJfn ..,..ea of insect study that deals with insect/host Plan,t
i~l'lliliffi with respect to infestation of cultivated crops
andlO}'ll~t~~5>Ck~,hedamage c~used and their control in ord~r
to obtai rill~ YIelds. Here IS my account of stewardship
spanning {~ period of over thirty two (32) years in this
University. ";', I.
Since the beginning, man by his inquisitive nature on life
sustainability has from time to time explored the environment
fOf sekaion and domestication, at: Dlants, and animals for
••••• doGf.tingami 9IDtlnm:. 1FIhe utIuntF rrOlm nomadic: life on'
• C Ering fruits, ~,lluutblganimals:. to)dhealmtary form'
~ apiculture whereby nearb~ land is tiHkdf ffurgmwing crops
and rearing animals indeed! lIIIlIikedthe origin' of organisms
known as pests. The practice of growing crops or rearing
animals together within a given area attracts these insects
which consequently multiply in large. numbers to become the
pests that destroy the crops and animals. Left alone in nature,
these organisms, insects inclusive, interact in such a way that
their population is in equilibrium with other living things
(plants, animals) in the environment over a long period of
time and thus establishes a General Equilibrium Position
(GEP). Man's tampering with this near-stable environment by
cultivating the land for crop and animal productions has
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displaced this equilibrium with the attendant rise in the
number of the organisms or pests to reach the economic
threshold and economic injury level (fig. 10).
- - - - - - =t:••, - - ECOnoftlk:lnjuryw.,e(I - - -£tonornic ThnithoW
I /'
: I
, I
11t---jl-:t-T+-++~t-I:-J4-/':.J., Gtnt~8JuiUbriu",
l. Palit;a" (GEP )
1•••
r..•• • eor$ )
Fig. 10: A theoretical pest population rising to economic threshold and
economic injury level.
The economic threshold is the density at which control
measures should be determined to prevent an increasing pest
population from reaching economic injury level. In other
words; it. is an .aetion thresihOlHat!wffiilthone should kick-start
control', meaamYSS.However; economic: injury level is the
lowest gcslt lJIIlPllati<»l1 tttatl will: cause, economic damage
while.:tft' •••• lii.Lctamage·is;tH~diljurythan will justify the cost
of artifi'Ciirnamntol measure and for it to take effect.
Bactors affecting the Development of Insects to Pest
status
The following factors: wdlithrow more light into how insects
rise to a pest status.
(1) The selection of crops for palatability and nutritive
value by man for growth, development and healthy
living is also carried out by insects for the same
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purpose. Therefore insects compete very well with
man for food.
(2) The practice of monoculture whereby one .crop
species is grown over a large hectarage has
provided abundant and closely grown plants readily
available as food sources, but also for cross
infestation.
(3) The practice of seed storage in large granaries such
as the big silos at one of the Federal Government
Strategic Grain Reserves situated along Iwo Road,
opposite Dizengoff Company, in Ibadan. This
provides a suitable habitat for continual repro-
duction and population build-up of stored product
insects such as the bean beetle, Callosobruchus
maculatus on cowpea; grain weevils, Sitophilus
zeamais, S. oryzae on maize and rice, respectively
as well as Dermestes maculatus on stored animal
products such as smoked fish, stockfish, leather, etc.
(4) The transfer of insects across geographical barriers
leaving behind their natural enemies will allow
them to multiply unchecked until they attain pest
status. This is clearly evident in the citrus scale
insect, Icerya purchasi, which was imported along
with good varieties of citrus from Australia to
California in USA leaving behind its natural enemy,
Rodolia cardinalis. It Was not until .rhis natural
enemy was exported to California to .deal with this
scale insect that it got eradicated. This was the first
classical case of biological control of insects. Right
here in Nigeria, Professor Odebiyi in his 2004
Inaugural Lecture reported the successful control of
the Cassava mealybug and Mango mealybug that
threatened cassava and mango production in 1979
and 1987, respectively. This was achieved through
the release of their natural enemies into the field
and they eventually got controlled.
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Insects in Relation to Crop Commodities and Plant Health
It is convenient to group crops according to the commodities
they supply and for pest identification and management
purposes. Thus, there are groups such as the cereals, legumes,
vegetables, fibres, porno logy , floriculture, tree crops and
stored produce. Each of these groups is infested by insect
pests to varying degrees, some as major pests and others
minor pests, all impairing the growth and productivity of such
crops culminating in yield and quality reduction. Evidence of
research work conducted on major insects attacking some of
the crops in each group, as my contribution to knowledge,
will suffice.
Insect Pests of Cereals
The most important cereal crops cultivated in Nigeria include
maize (Zea mays), rice (Oryza spp.), guinea corn (Sorghum
spp.), millet (Pennisetum typhoides), and wheat (Hordeum
triticum). They are a good source of carbohydrates in human
diets and animal feed, and supply the needed energy. In table
1, the field insect pests of cereals are the stem borer complex,
Eldana saccharina Sesamia calamistis, Busseola fusca,
Acigona ignefusalis and Mussidia nigrivenella found to cause
damage on farmlands in South-Western Nigeria during the
early and late cropping seasons in 1991. E. saccharina and S.
calamistis caused the highest percentage stalk length damage
(Oigiangbe et al. 1997). However on rice, the lepidopterous
stem borer complex was the most damaging, including the
pink stem borer, Sesamia calamistis; yellow stem borer,
Scirpophaga incertulas; striped borer, (Chilo suppresalis);
Maliarpha sp. and a dipterous stem borer, Diopsis thoracica
(Stalk-eyed borer) (fig. 11). Their effect is more severe in the
late cropping season than in the early season. The two
symptoms associated with stem borer attack are the 'window
pane effect' (fig. 12) and 'dead heart' in maize but 'dead
heart' and 'white head' (fig. 13) in rice. Up to 30% loss of
stands has been recorded in severe infestation by these borers.
Rice grains especially at the dough stage are attacked in the
19
UNIVERSITY OF IBADAN LIBRARY
field by grain suckers, Aspavia armigera and Stenocoris
elegans (Joda 2000; Alamu and Ewete 2014). A survey across
fifteen (15) states in Nigeria, namely; Abia, Anambra, Delta,
Ebonyi, Ekiti, Enugu, lmo, Lagos, Nassarawa, Niger, Ogun,
Ondo, Oyo, and Plateau, revealed three (3) species of Aspavia
and their natural enemies (Joda 2000).
Table 1: Mean Number of Stemborer Species per Stalk during the
First and Second Cropping Seasons in South Western Nigeria
Borer species . Season N No of CV(%) t-value
Stemborers
Eldana First 850 0.77 56.71 0.1241ns
saccharina
Second 330 0.71 22.82
Seasamia First 850 0.51 83.14 4.2193*
calamitis
Second 330 0.81 35.61
Acigona First 850 0.11 256.28 1.8229ns
ignefusalis
Second 330 0.21 20.90
Busseola fusca First 850 0.01 207.45 2.5505*
Second 330 0.08 55.73
Mussidia First 850 0.00
nigrivenella
Second 330 0.35 52.69
ns= Not significant at P= 0.05, *= Significant at P ::;0.05
20
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l, 2J?~qh9UtI
I:) zuonrmuge.I
q noegiq .fTf;'Xi
b'JL/t" J?Orti 'Al!
Fig. 11: Diopsis tho'flitiC'f'(s~-iym1x>ter. bO,,'3.J II
D:52U '1:)11£1~1rl1 .:).1 'l :.J rDl!uolg bus
»q b-l1; fll.;'Jd L'Oc .t;:.Jq'IJO::l
q j ~")tJqlf1')~fl(Y)
1L)dJ ~ filJ! :;J,lIJ;
!2;:}(] bi~il ern
:31 'J:nrlJ 5(5 d
.znitrh 1'JIIOrt
OJ <xlJ vlrusm
iT ~Golihi'(
)' }\\\n'l\ m\')
brrs 'i~)~\'\\')'\)
1 :) :nJ; 2~dd
brrs '(:goloid
one UiBllWg.3
) , I rus ~jJN3
u 2Ji )~1~lqno')
.ioq rTWO"lH e'tl no
.QQ ( , 2k.l:)w F_ bns
Fi.g~.;r1-.2'X-. ';>n'e}1w5!1 i:bdow pan£errewffbect' bsy::m15p2tomlfI5o:t.ns·
UNIVERSITY OF IBADAN LIBRARY
Fig. 13: The 'white head' of stem borer attack in rice.
Insect Pests of Legumes
Leguminous crops which include groundnut, cowpea, soya
bean, pigeon pea, sword bean and bambara groundnut supply
the most needed plant protein in the diet of human beings and
livestock. Groundnut is processed into both the groundnut oil
and groundnut cake, the latter used in animal feed. However,
cowpea, soya bean and pigeon pea are grown for human
consumption for the needed plant protein. Field insect pests
- attacking them have been well documented and studied. Of
the field pests at the vegetative and reproductive phases of
these three legumes, pests of the reproductive phase mainly
flower thrips, Maruca pod borer and the pod sucking bugs,
mainly the coreids and alydids, cause over 50-70 percent seed
yield loss. The coreid bugs include Anoplocnemis curvipes,
CZavigraZZatomentosicoZZis while the alydids are Riptortus
dentipes and Mirperus jacuZus. The most studied of these
bugs are C. tomentosicoZZis and R. dentipes in terms of their
biology and damage caused on cowpea (Aina 1972; 1975a;
Egwuatu and Taylor 1977; Akingbohungbe 1977). However,
Ewete and Niba (1994) showed that Mirperus jacuZus
completed its development (first instar - adult) in 19.8 days
on Ife Brown cowpea variety and infestation of pods 2 weeks
and 3 weeks after pod development caused 85.6-99.0 percent
and 61.0-66.8 percent seed damage, respectively, at a
22
UNIVERSITY OF IBADAN LIBRARY
population of 8 bugs per peduncle (table 2). Similarly, Ewete
and Joda (1996) showed that Riptortus dentipes at a
population of 8 bugs per plant caused 99.0-100.0 percent seed
damage on soya bean varieties TGX 536- 02D and TGX 849-
294D but 90.5 percent seed damage on TGX 996-28E
(table 3).
Table 2: Percentage Seed damage (± S.E.) with varying Densities of
Mirperus jaculus on Cowpea at three different Pod Ages
Insect Number Age of Pods
1 Week 2 Weeks 3 Weeks
o (Control) 7.62 ± 1.38 b 7.90 ± 2.14 c 8.02 ± 2.40 b
2 100.00 ± 0.00 a 85.60 ± 4.99 b 61.00 ± 12.95 a
4 100.00 ± 0.00 a 93.00 ± 4.52 d 64.80 ± 6.60 a
8 100.00 ± 0.00 a 99.00 ± 1.00 a 66.80 ± 13.85 a
S.E. 1.8 7.49 19.82
CV% 2.34 10.49 39.5
Means followed by the same letters are not significantly different at 5 % level
(Duncan's multiple range test): mean of 5 replications.
Table 3:Degree of Seed damage (%) on Soybean caged with varying
Densities of ~iptortus dentipes
Insect Number Soybean
Varieties·
TGX536.02D TGX 996.28E TGX 849 294D
o O.Oa 2.6a . l.4a
2 82.5b 29.9a 66.3b
4 98.5c 83.8b 80.0b
8 99.2c 90.5b l00.0c
S.E 5.20 10.09 4.41
CV (%) 3.21 8.44 3.08
Means followed by the same letters are not significantly different at 5% level
(LSD)
Insect Pests of Vegetables
Vegetables (leafy and fruit), supply minerals and vitamins
needed for good and healthy growth of man and his animals.
·A good example of fruit vegetables are okra, tomato, pepper,
garden eggs, eggplant, cucumber, water melon, et cetera.
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Some of the leafy vegetables are Amaranthus spp (Tete),
Celosia argentea (Soko), Telfairia occidentale (Ugwu or
iroko), Basella spp (Amunututu), Corchorus olitorius
(ewedu), Vernonia amygdalin a (bitter leaf) and Cabbage.
They are infested by defoliators, mostly beetles, larvae of
butterflies and moths as well as the grasshoppers, while their
fruits or grains are attacked by hemipterous bugs. Ewete
(1978) identified six (6) major groups of insects infesting all
parts of okra plants namely; foliage-feeders, root-feeders,
stem-feeders, flower bud-and flower-feeders and fruit-
feeders. Among these pests are three (3) major defoliators,
Podagrica sjostedti, Podagrica uniforma , Sylepta derogata
(leaf-roller); six (6) major green and dry fruit-feeders,
Dysdercus (superstitiosus) voelkeri (fig. 14), Oxycarenus
hyalinipennis, O. gossypinus, (fig. 15), Earias biplaga and
Earias cupreoviridis as well as two (2) major stem-feeders,
Hypolixus nubilosus and Alcidodes crassirostris. Ewete et al.
(1980) showed that the problem of poor seed viability was
solved in okra by timely harvesting of okra fruits when they
are 28 to 35 days old on the plant and the seeds attain high
germination (table 4). The okra fruits harvested at this stage
showed ripening colour and splitting along the ridged fruit
wall and with seeds already turned black but not yet dried.
This tended to avoid excessive feeding by seed bugs
(Dysdercus sp) which aggregate on the fruits (fig. 1) when
allowed to remain completely dried on the plant before
harvesting for seed production as practised by the local
farmers.
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Table 4: Comparison of Treatment means on Okra Seed Germination
(Summary of 1974/75 Experiments)
Days after Mean seed germination (percent) in okra
flower opening Early season Late season Early season
1974 1974 1975
14 o c 1.7 d 0 d
21 13.0 b 33.3 b 14.3 c
28 28.3 a 68.7 a 49.7 b
35 38.3 a 65.0 a 72.7 a
42 36.0 a 65.7 a 55.3 b
86 o c 16.0 c 0.3 d
(Completely
field-dried)
Means followed by the same letters are not significantly different at P = 0.05.
Fig. 14: Dysdercus superstitiosus, a major green and dry fruit-feeder.
25
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(
Fig. 15: Oxycarenus gossypinus, a major green and dry fruit-feeder.
In another study on insect pests infesting the leafy vege-
table, Amaranthus spp, the two major defoliators identified
were Hymenia recurvalis and Psara bipunctalis while Cletus
fuscescens and Aspavia annigera were the major grain or
seed feeders. The defoliators infest Amaranthus from 3-4
weeks after planting (WAP) and skeletonises the leaves at 4-5
WAP as the leaves are ready for harvesting and consumption.
What a right time to strike and readily deprive the farmers of
their harvest!
In our study on the survival of C. fuscescens on five
species of Amaranthus, the wild Amaranthus (A. spinosus) is
as good as four other cultivated amaranths (A. cruentus
(grain), A. cruentus (leafy), A. dubius (leafy), A. hypo-
chondriacus (grain))· in supporting the biology and high
survival of Cletus fuscescens (table 5), and hence acting as a
major link in their infestation (Ewete and Ukwela 1991).
Thus a first step in the management of this pest is to destroy
suspected wild alternative host plants around the farm during
its cultivation.
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Table 5: Nymphal Survival (%) of Cletus fuscescens on Five Species of'Amaranthus
Nymphal
instars
Food sources I II III IV V Mean nymphal
survival
Amaranthus hypochondriacus (grain) 88.9 90.0 80.6 86.2 84.0 85.9a
Amaranthus spinosus (weed) 92.5 68.6 86.4 92.2 80.8 84.1
Amaranthus dubius (leafy) 92.3 83.3 70.0 76.2 87.5 81.9a
Amaranthus cruentus (leafy) 83.3 82.5 60.6 75.0 93.3 78.9a
Amaranthus cruentus (grain) 76.1 68.6 91.7 68.2 80.0 96.9a
Means followed by the same letters are not significantly different at 5% level.
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Insect Pests of Fibre Crops
The well known fibre crops are cotton, kenaf, roselle, sisal, et
cetera. Cotton is grown for its lint used in sericulture and
cotton seed for its oil and cake for livestock feed. The bast
fibres of kenaf and roselle are used in making jute bags and
ropes. However, cotton, kenaf and roselle belong to the
family Malvaceae as okra. They are infested by similar insect
pests, the seed bugs, Dysdercus spp and Oxycarenus spp,
inclusive. Extensive research work had been conducted on
Dysdercus spp (Cotton-stainer) infesting cotton and okra,
while Oxycarenus spp was neglected. This prompted my
doctoral study on the ecology and biology of Oxycarenus
gossypinus and the damage caused on okra as well as on the
alternative host plants, cotton, kenaf and roselle. On its
biology, Ewete and Osisanya (1988) showed that the egg
incubation period was 6.98 days and the mean developmental
period (first instar - adult) was 16.7 days, and there were 5
nymphal instars whose morphometric measurements and
immature stages were also reported (Ewete 1984) (fig. 16).
Ewete and Osisanya (1985) also showed that the nymphal
developmental period on four food sources (seeds) - okra,
kenaf, roselle and cotton averaged 15.5, 15.7, 15.8 and 18.1
days, respectively (table 6). This implied that okra, kenaf and
roselle should not be grown in the vicinity of cotton to avoid
early infestation that will reduce cotton yield.
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~
I·Om.,
Fig. 16: Eggs and larval instars of Oxycarenus gossypinus distant.
29
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Table 6: Mean Duration (days ± SE) of Nymphal Development in O. gossypinus reared on Dry Seeds of four
cultivated Malvaceae (range in parenthesis)
Nymphal instars Mean period*
Food source of nymphal
First Second Third Fourth Fifth development.
Okra 3.27±O.18 3.80±O.26 2.0±O.O 2.40±O.13 4.0±O.O 15.47±O.39b
(2-4) (3-5) (2) (2-3) (4) (13-18)
Cotton 4.0±O.O 3.67±O.28 3.0±O.O 2.30±O.15 5.17±O.3J 18.14±O.48"
(4) (3-5) (3) (2-3) (4-6) (16-21)
Kenaf 3.0±O.O 3.63±O.1l 2.63±O.11 2.14±O,10 3.74:tO.1O 15.74±O.23b
(3) (3-4) (2-3) (3-4) (3·4) (13-17)
Roselle 3.13±O.ll 3.0±O.O 3.0±O.O 2.83±O.O8 3.86±O.O7 15.S2±O.lSb
(2-4) (3) (3) (2-3) (3-4) (13-17)
Means followed by the same letters are not significantly different at 5% level
*Mean periods of nymphal development are significantly different (F = 3.18; PI! 0.05).
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Stored Product Insects
Storage of agricultural products forms an integral part of
farming practice whereby farmers produce in excess of family
needs and the rest could be stored for various reasons. The
reasons for storage include the continued sustenance of life or
for future planting or until the produce commands higher
price, or against a period of any disaster (drought, flood, war
or insurgency as in Boko Haram). Such a storage condition
provides an excellent condition for a field-to-store insect
developing into a pest status. This is particularly true of
insects infesting stored cereals (maize, rice, guinea com,
wheat) such as Sitophilus zeamais, S. oryzae, S. granarium;
stored pulses (cowpea, pigeon pea, soya bean) such as
Callosobruchus maculatus; stored animal produce (smoked
fish, stockfish, leather) such as Dermestes maculatus; stored
cocoa beans such as Ephestia cautella; stored Cola nut such
as Balanogastris kolae (Ivbijaro 1975); Sophrhorhinus
insperatus, S. gbanjaensis (Daramola 1973) to mention a few.
The control of this group of insect pests has been centred on
the application of fumigants such as methyl bromide, phos-
phine gas marketed as phostoxin or quickphos, and actellic
dust (pirimiphos-methyl).
Effective as these synthetic insecticides are, they inflict
side-effects on humans and the environment through the
depletion of the ozone layer, and consequently their ban. This
has prompted the search for alternatives with the searchlight
beamed at investigating the use of plant natural products or
insecticides of plant origin. Isman (1994) highlighted five
botanical insecticides registered for use in USA namely;
Pyrethrum from Chrysanthemum cinerariaefolium (flower);
rotenone from Derris elliptica and Lonchocarpus sp. (roots
and tubers); ryania from tropical shrub, Ryania speciosa
(stem wood); Sabadilla from South American Veratrum
(seeds) and azadirachtin from neem, Azadirachta indica
(seed).
My interest in the use of natural product insecticides in
controlling insects was1foused during my one-year
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sabbatical leave in 1993 at the Department of Biology,
University of Ottawa, Ottawa, Ontario, Canada, with two
scientists, Professors J.T. Amason (botanist) and BJ.R.
Philogene (entomologist) as my hosts under the 1992
Canadian Fellowship of CIDAINSERC. Similarly, I was a
visiting scientist in 1997 at the Scottish Agricultural College,
University of Edinburgh, Edinburgh, Scotland with Dr. Andy
Evans as my host under the 1996 Royal Society Third World
Fellowship to test the efficacy of the stem-bark extracts of
five Khaya species against the cabbage defoliator.
In a study on the biological activities of four traditionally
used Nigerian plants, Ewete et al. (1996) showed that
ethanolic extracts of Piper guineense (Piperaceae), Cedrela
odorata (Meliaceae), Dennettia tripetala (Annonaceae) and
Aframomum melegueta (Zingiberaceae) in artificial diets
significantly reduced larval growth of European com borer
(ECB), Ostrinia nubilalis, at a concentration of 1000ppm
(0.1%) (table 7). It is noted that O. nubilalis exhibits the same
symptom (window pane) as Busseola fusca on maize leaf in
the tropics. Further tests on the nutritional indices for
habituated 3rd instar larvae with the two most promising plant
extracts indicated that P. guineense and C. odorata extracts
showed the best potential for development as botanical
insecticide. The active compounds, piperine from Piper and
gedunin from C. odorata were compared for efficacy with
their respective crude extracts against ECB. It was shown that
piperine had no marked effect at reducing maximum larval
weight but caused larval mortality compared with the crude
extract, but gedunin, C. odorata crude extract prolonged
larval development and adult emergence of ECB (Ewete et al.
2000) (table 8). This implied that certain compounds exist
within the crude extract of Piper which are acting as
synergist(s) and this may have accounted for the efficacy.
32
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Table 7:The Effects of Plant Extracts on Larval Growth ot
O. nubilalis
Plant species Weight gain (s.d.) of second instar larva (mg)
Concentration
0 10ppm 100 ppm 1000 ppm
0 10ppm 100 ppm 1000 ppm
Piper guineense 3.08a 3.85a 3.08a 0.96b
(1.2) (1.0) (1.6) (0.3)
Cedrella odorata 4.00a 3.60ab 3.21b o.sse
(1.0) (1.0) (1.2) (0.3)
Xylopia aethiopica 3.78a 3.69a 3.87a 3.84a
(1.6) (1.0) (1.6) (1.2)
Dennetia tripe tala 5.79a 3.13b 3.28b 2.21b
(1.1) (1.4) (1.3) (1.0)
Aframomum melegueta 4.72a 4.95a 4.58a 2.76b
(1.5) (1.3) (1.5) (0.9)
Means followed by the letter in a row are not significantly different in the SNK
test (P = 0.05)
Table 8:Effects of Gedunin and Piperine on Larval Weight (mg) and
Mortality of Ostrinia nubilalis (s.d. in parenthesis)
Larval mortality (%) Larval wt. at day 12
at day 8 (% control)
Concentration Gedunin Piperine Gedunin Piperine
Oppm 6.7 3.3 l00±23.1 lOO±15.7
5ppm 6.7 0 46.0±11.3 79.3±14.1
lOppm 3.3 3.3 45.7±14.0 112.5±13.4
20ppm 3.3 3.3 43.9±15.2 148.5±14.8
40ppm 6.7 23.3 43.3±16.2 103.6±17.1
In another study on the insecticidal activity of the extract
of an Asian shrub, Aglaia odorata (Meliaceae), and the
purified active principle, rocaglamide, from same plant,
Ewete et al. (1996) showed that the extract was a potent
inhibitor of larval growth of ECB at dietary concentrations
12.5-lOOppm (fig. 17). The dietary concentrations of 0.1 and
0.2ppm of rocaglamide strongly inhibited larval growth and
survival of ECB (table 9, fig. 18). Rocaglamide was more
potent than azadirachtin which had earlier been reported to be
the most potent natural product ever tested by Amason et al.
(1985).
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UNIVERSITY OF IBADAN LIBRARY
- 10.rs;n
::E
O'l
'~
~
~~
~
Ii::
("IS
c:p
E
OJ
.0
0-1
..)
5 10 15 20 25 30 35
Larval age (days)
--0-- control;
-.0-- 12_5 pprn;
--0- 25ppm;
A 50 pprn;
m 100 PPFtl
Fig. 17: Effect of dietary administration of A odorata extract on larval
growth of O. nubilalis.
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Table 9: Mean Weight gained and total Mortality of O. nubilalis
Larvae exposed to Dietary Concentrations of Rocaglamide over a
15 day period
Rocaglamide in diet Mean weight gain Total mortality
(ppm) (mg) (%)
0.0 69.71±3.40 a,b 7.4
n=24
0.0125 76.63±5.84 a 13.3
n=25
0.025 84.72±4.78 a 16.6
n=22
0.05 58.46±3.99 b 43.3
n= 19
0.1 31.94±3.16 c 60.0
n=24
0.2 5.3±1.l5 d 85.0
n= 13
Means are ± S.E.M.; means followed by the same letter do not differ significantly
using a Student-Neuman-Keus (SNK) test at P 0 0.05.
35
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ao,---------~------------------~
60
C-»E1:
.f;i!! 40
t:
:I:;
20
o~~~~==~~~----__----~
o 5 10 15 20
Larval age (days)
Ia p onnltol;
&I O.05ppmj
--0- 0.1 ppm:
o O.2ppm:
Fig. IS-:·Effect of dietary administration of rocaglamide on larval growth
of O. nubilalis.
With these positive, results- on) the, biolngicalt alldRiWafrRUmt
natural: n~.~ wc.m: amnlIIIIttIdIronttllel.Uleaftn1ant·
extracns ttDuw'lttdhttDodigJlDilmttiitr.iW.tl>'" ~ am altbrllliltWe tro
synttllllt~ ffimigarrts.. Iln atm· flrst' test on the bioactiv.i~ <Iff
36
UNIVERSITY OF IBADAN LIBRARY
extracts of three plants, Khaya ivorensis (Meliaceae), Citrus
sinensis (Rutaceae) and Strombosia pustulata (Olacaceae),
Ewete and Barnigbola (1998) showed that the extract of K.
ivorensis at 500-1000ppm significantly reduced the number
of emerged Fl progeny of Callosobruchus maculatus on
Bambara groundnut and subsequently continued at F2 and F3
generations: two and four months, respectively, while that of
S'. pustulata was moderately bioactive at 500-1000ppm, and
C. sinensis extract was ineffective (fig. 19). Extract of K.
ivorensis at lOOOppmsignificantly reduced both reproductive
efficiency of mated females of C. maculatus (table 10) and
percentage seed damage on Bambara groundnut seeds
(table 11).
160
140 "'"+-c .•••••
120 ...• s.pe •••••••
100 ....••.I(.~
80
60
.---------------- ~L_~
o 2SO 500 1000
Concenirations (ppm)
Fig. 19: Effect of plant extracts on egg laying of Callosobruchus
maculatus on Bambara groundnut.
37
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Table 10: Mean Number of Emerged F1Progeny of Callosobruchus
macula/us on Bambarra Groundnut Seeds treated with Plant Extracts
Plant Oppm 250ppm 500ppm 1000 ppm
extracts (control)
Khaya 32.50a 31.OOa 15.25ab 1O.00b
ivorensis (10.9) (15.2) (5.5) (6.6)
Strombosia 41.50a 47.50a 32.25a 30.27a
pustulata (12.0) (4.6) (7.9) (8.5)
Citrus 69.00a 67.50a 91.75a 64.25a
sinensis (6.2) (28.3) (14.7) (7.5)
(± SE in parenthesis)
Means with the same letters along the row are not significantly different at 5%
level (Duncan's Multiple Range Test).
Table 11: Mean Number of emerged FrF3 Progeny of Callosobruchus
maculatus on Bambarra groundnut Seeds treated with extracts of
Khaya ivorensis
Khaya ivorensis . Emerged
(Concentration) Fl Progeny adults F3 Progeny·F2 Progeny
Oppm 32.5a 66.5a 91.5a
(10.9) (11.1) (13.3)
250 ppm 31.0a 48.3a 67.0a
(15.2) (14.4) (12.0)
500ppm 15.3ab 27.8ab 42.8a
(5.5) (9.7) (12.6)
l000ppm 1O.Ob .; lO.3b ll.3b
(3.3) (6.3) (7.4)
(± SE in parenthesis)
Means with the same letters along the row are not significantly different at 5%
level (Duncan's Multiple Range Test).
In a study on effects of stem bark extracts of three Mahogany
species, Entandrophragma cylindricum, Cedrela odorata and
Swietenia mahogani on maize weevil, that of E. cylindricum
and C. odorata at 500-1000ppm significantly reduced the
number of eggs laid on treated grains (table 12) and
significantly reduced the number of emerged Fl progeny
(table 13). Extract of S. mahogani was inactive (Ewete and
Alamu 1999). Babarinde and Ewete (2008) reported that
38
UNIVERSITY OF IBADAN LIBRARY
extracts of three Khaya species; K. grandifoliola, K. nyasica
and K. senegalensis at 250-1000ppm significantly reduced
oviposition of C. maculatus on treated cowpea seeds as well
as caused significant reduction in oviposition efficiency of the
female insect (tables 14, 15). In a study in Cameroon, Akob
and Ewete (2007) reported that ashes of Eucalyptus grandis
and Ocimum gratissimum leaves at the rate of 0.25g/25g
grains significantly reduced the number of emerged maize
weevils (table 16).
Table 12: The Mean Number of Eggs laid by Sitophilus zeamais on
Grains treated with Mahogany Extracts
Mahogany Extracts Concentrations (ppm)
o ppm 250 ppm 500 ppm 1000 ppm
Entandrophragma 5.55a 42.5a 25.0a 35.0a
cylindricum (9.7) (7.4) (1.89) (3.2)
Swietenia mahogani 56.8a 41.0a 32.0a 32.0a
(12.6) (4.7) (5.1) (6.0)
Cedrela odorata 47.5a 23.8a 30.3a 14.0b
(15.3) (8.1) (6.2) (4.4)
(± SE in parenthesis)
Data are means of four replicates
Means followed by the same letters in the row are not significantly different at 5%
levels (Duncan's Multiple range Test)
Table 13: The Mean Number of Fl Progeny of Sitophilus zeamais on
Grains treated with Mahogany Extracts
Mahogany Extracts Concentrations (ppm)
Oppm 250 ppm 500 ppm 1000 ppm
Entandrophragma 17.0a 18.0a 6.5b 6.8b
cylindricum (2.9) (1.9) (1.06) (2.3)
Swietenia mahogani 17.8a 21.0a 16.3a 15.0a
(6.3) (6.0) (2.8) (3.1)
Cedrela odorata 253a 20.8ab 19.0aba ll.3b
(7.8) (7.3) (6.1) (4.8)
(± SE in parenthesis)
Data are means of four replicates
Means followed by the same letters in the row are not significantly different at 5%
levels (Duncan's Multiple range Test)
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Table 14: The Mean Number of Eggs (± S.E.) laid by Callosobruchus on
Cowpea treated with Khaya Extracts
Extracts Mean number of eggs at different concentrations (pprn)
o 250 500 1000
K. grandifoliola 310.0± 3.2 a 106.3±6.7 b 147.5±33.3 b 75.5±21.6 b
K. senegalensis 310.0± 3.2 a 183.5±20.7 b 169.5±29.9 b 156.3±43.8 b
K. nyasica 310.0± 3.2 a 231.5±23.0 b 224.8±27.5 b 165.8±40.0 b
Data are means of four replicates
Means followed by the same alphabet in a row are not significantly different at 5% probability level.
Table 15: The Reproductive Efficiency (± S.E.) of Callosobruchus maculatus
exposed to Cowpea treated with Khaya Extracts
Extracts Mean number of eggs at different concentrations (ppm)
o 250 500 1000
K. grandifoliola 75.6± 6.1 a 58.6±7.0 b 58.3±8.6 b 47.9±13.6 c
K. senegalensis 75.6± 6.1 a 74.0±6.4 a 59.7±5.5 b 60.0±7.6 b
K. nyasica 75.6± 6.1 a 55.6±7.4 b 57.4±6.1 b 49.7±5.8 b
Data are means of four replicates
Means followed by the same alphabet in a row are not significantly different at 5% probability level.
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Table 16: Effects of Ashes of Four Plants on the Number of emerged F 1 Progeny of
Sitophilus zeamais infesting Maize
Mean no. (±SD) of emerged Fl progeny
Plant material Cupressus Eucalyptus Ocimum Vetiveria
ash dosage (g) arizonica grandis gratissimum zizanioides
o (Control) 16.3 ± 2.4 16.5 ± 2.7 15.0±2.2 14.5 ± 2.5
0.10 4.75 ± 1.5 5.5 ± 1.1 8.0±1.9 10.3 ± 1.9
0.25 4.5 ± 1.1 1.0 ± 1.2 2.5±1.l 4.5 ± 1.0
0.50 5.8 ± 1.9 3.25 ± 1.5 6.0±1.2 7.0 ± 1.2
1.00 6.0 ± 1.9 3.0 ± 1.6 6.0±1.6 5.3 ± 1.5
LSD(o.05) 2.7
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Are Insects really Friends or Foes?
Mr. Vice-Chancellor, I am now back to the topical issue of
the day and that is, Are insects friends or foes? I have in the
last fifty minutes appraised the contributions of insects to
mankind in order to arrive at a fair and just answer to this
question. .
It is a truism that by man's activity of practising sedentary
form of agriculture whereby a forest is opened up and the
land tilled for cultivation of crops and rearing of animals,
man has tampered with the natural biotic balance of his
environment. That is the consequence of what we are now
experiencing with some of the organisms increasing in
population to become pests. They depend on these cultivated
crops or reared animals for their feeding either in the field or
in storage and for their survival. It is in the process of feeding
and causing damage that they compete effectively well with
man for the food produced. Are they to blame for this?
Definitely No. From the agricultural point of view, we have
heard in this lecture, the damage caused by insects on
cultivated crops, while farmers produce food for their own
needs, thereby leading to yield reduction both in quantity and
quality. Typical examples of these are the defoliators on
vegetables, the stem borers on cereals, the thrips and pod
sucking bugs on beans (legumes) and the stored product
insects on stored grains and dried animal products (smoked
fish, stockfish, leather).
In Veterinary Entomology, haematophagous insects such
as the tsetse fly and horse fly; ectoparasitic insects such as
Menopon gallinae (bird louse), Haematopinus suis (pig louse)
transmit diseases to their hosts leading to fatalities in animal
production. Also in Medical Entomology, haematophagous
insects transmit deadly diseases such as the yellow fever,
malaria fever, dengue fever, river blindness, cholera,
diarrhoea and dysentery all decimating human lives. Even the
common blood sucking bed bug (Cimex sp.) causes
discomfort and irritation to humans on the bed. There are
those that are ectoparasitic on human head, Pediculus
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humanus capitis or on human body, Pediculus humanus
corporis or even in human private areas-the crab louse,
Phthirus pubis that settles for the pubic hairs. What a place to
invade!
They cause discomfort and irritation on the infested parts.
From this viewpoint, insects can be regarded as foes. But
according to Youdeowei (1977), only a few insects, about
0.3% of the over 3,000,000 insect species known in Tropical
Africa are either the major or potential pests causing this
trouble for man. The remaining 99.7% are insects that are
beneficial to man. This is clearly evident from my earlier
submission in this lecture. Insects help to increase crop
productivity as excellent pollinating agents, and in rejuvena-
ting soil fertility. They also produce useful commodities for
man's use. The honey produced is utilized for food in the
homes and medically for preventing bacterial infection on
wounds and bums.
Mr. Vice-Chancellor, with regards to sweetness, I know
no other product in my discipline that is sweeter than honey
in this world. May be the Vice-Chancellor knows any other
thing that is sweeter than honey in his medical discipline. But
a friend of mine, Mr. Raymond Unamma, once told me in
pidgin English: "Something wey dey sweet, e dey bitter".
That is why even from the sweetness of honey, the producer
also stings and can even sting to death. So beware when you
lick honey or eat something very sweet. Besides, insects are a
source of protein and cholesterol-free oil/fat in human diet
and for healthy development. They can also be used to
unravel very intricate murder cases shrouded in utmost
secrecy. Therefore, on the balance of probability, insects are
more beneficial to man than harmful.
Conclusion and Recommendation
Mr. Vice-Chancellor, everything that has a beginning must
have an end. Life in itself has an end. This Inaugural Lecture
of today must end. But before then, ~ndly permit me to make
the following observations and/or remarks.
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The hitherto comatose Teaching and Research Farm
which is our field laboratory is now rising from its slumber.
Never will it go back to that stage again. I remember vividly
the challenge thrown by my good friend, Professor E.
OIabode Lucas in his 2007 inaugural lecture, that any Vice-
Chancellor who could resuscitate the Teaching and Research
Farm of this Faculty would have written hislher name in gold.
Mr. Vice-Chancellor, you have indeed done so. This was a
project conceived during the windfall of the Federal
Government N5.5 billion intervention fund and initiated by
Professor Bamiro's administration, the immediate past Vice-
Chancellor, and also during my deanship of the Faculty. You
indeed continued with it and its all success galore. We of the
Faculty of Agriculture and Forestry owe you and your
Management Team a debt of gratitude for this and all the
other innovations you have executed in the Faculty. May I
also add sir, that the splitting of our Faculty into two to allow
the Forest Resources Management component regain their
freedom should be implemented to completeness. It was
approved at the Senate meeting of Wednesday 4 May, 2010
during my tenure as Dean of the Faculty.
Back to our insects, for as long as man lives, insects will
continue to live with himlher in public or in private and also
share the same food and environment. After all, we also
derive benefits from them and vice versa. Or don't we?
Therefore, entomologists and insects will continue to manage
each other for life to continue in a balanced nature. Hence, I
charge the Vice-Chancellor to challenge entomologists and
organic chemists of this University with proper funding and
enabling environment to come up with an insecticide of plant
origin to be patented and code-named 'Recticide' or
'Sapericide' (from Recte Sapere fons) for the management of
stored product insects. After all, the Rothamsted
Experimental Station in England patented Pyrethrin from
Chrysanthemum and is. marketed as Pyrethroids, a new
generation insecticide now used worldwide for insect control.
The University could also benefit financially from this.
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Acknowledgements
First, I must give thanks to Almighty God for sparing my life
and for making this day a reality. There is no one to serve
other than Him. I must also express my deep gratitude to my
parents, High Chief Jacob Ewete and Madam Abigael Ewete,
both of blessed memory. Though they could not read or write,
Papa was a goldsmith, trader and transporter. They provided
selfless and enabling condition financially and morally for me
and other children to attain the level of education each one
desired.
Similarly, I will like to thank all those who have assisted
me to climb this ladder through their contributions. I most
sincerely give gratitude to our erudite scholar and teacher, the
late Professor T. Ajibola Taylor, for providing me with
scholarship for my M.Phil. and employment at IAR&T, Moor
Plantation, Ibadan in 1977. He was an excellent man in the
pursuit of knowledge and he exuded excellence in whatever
he laid his hands. I also sincerely thank the late Professor
H.R. Chheda who was my undergraduate super-visor in the
Department of Agronomy. It was inconceivable that Professor
Chheda would carry me in his Ford Escort car from the old
Faculty (now PG School building) to Independence Hall in
1972 while working late on my project in the laboratory. I am
equally grateful to Dr. E.O. Osisanya who successfully
supervised my Ph.D. Mr. Vice-Chancellor, kindly permit me
to recount an incident that happened while defending my
Ph.D thesis on 2 August, 1984. Just about 15 minutes into the
examination and after sipping his coffee, he suddenly took ill
and he landed in Jaja Clinic. Certainly the examination could
not continue that day but was shifted to the following day. At
evening time when his condition did not improve, he was
transferred to UCH where he had to undergo a surgical
procedure due to ruptured duodenal ulcer. He survived the
ordeal and is now present at this lecture' even at 80 years of
age! I thank God for your life sir and your effort had not been
in vain.
I am grateful to all my postgraduate students past and
present who have contributed immensely to this success
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story, two of whom are now Professors. They are Professor
O.N. Oigiangbe of Ambrose Ani University, Ekpoma, Edo
State and Professor U.M. Ukwela of University of
Agriculture, Makurdi, Benue State. I will also like to
appreciate my former teachers in the Faculty, Professors
M.O. Adeniji, J.K. Egunjobi, G.M. Babatunde, Emeriti
Professors S. Kolade Adeyoju and D.U.U. Okali. I also thank
our Demonstrators in AGB First Year Practical classes who
were then postgraduate students and now Professors, namely,
A.M. Daramola, M.E. Aken' ova, Tonye Okorie, and Dr.
Olunloyo. Let me also appreciate my hosts, Professor J.T.
Amason and B.J.R. Philogene of University of Ottawa,
Ottawa, Canada for making my Sabbatical Leave in their
laboratory in Canada most fulfilling and Dr. John Larson who
collected me that night on my arrival in Ottawa bus station.
I also wish to thank a British couple, Mr. Judge Hibbard
and Mrs. Helen Hibbard who taught me Zoology and Botany,
respectively at the C.M.S. Grammar School, Bariga (formerly
Lagos Anglican Boy's Grammar School) for the Cambridge
Higher School Certificate in 1967/1968. I must also
appreciate and thank Late Chief E.O. Agagu who was my
principal at Manuwa Memorial Grammar School, Ijuodo,
Okitipupa for piloting us through those difficult and
exuberant era in the Secondary School. In 1966 when it was
very clear that the school was not approved to split the
sciences into Physics, Chemistry, Biology, the whole class
rebelled against him and he rusticated all of us for two weeks.
On returning to school and while registering us for the
W.A.S.C. examination, he observed on the register that I did
not opt for General Science. He asked me why? I replied that
I had just passed Chemistry and Biology at G.C.E. OIL
London in the result just released. He said I must register for
the General Science since we all gave him headache on the
issue. I will like to place on record Mr. Remi Rowaiye whose
teaching stimulated my interest in Chemistry through 1965
and 1966 at MMGS, Ijuodo. He is also here in this audience. I
also thank my classmates of the MMGS 1965/1966 Club for
honouring this occasion.
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I must pay special tribute to my two friends, Professor
Mobolaji Ogunsanya of the Department of Educational
Management, University of Ibadan and Dr. Oluyombo
Awojobi of Awojobi Clinic, Eruwa (ACE) who passed on
recently on 15 and 17 April, 2015, respectively. Yombo
Awojobi and I had been friends since 1967 from C.M.S.
Grammar School and we got married the same day in 1978
here in Ibadan. I am personally pained that I miss them on
this occasion. May their gentle souls rest in perfect peace,
Amen. I also thank my close friends, Professors S.O. Bada,
Iyi Fawole, E. Olabode Lucas, Alex Gboyega, all now
retirees of the University as well as Professor Anthony
Ologhobo. I also thank all members of the Entomology Unit
of the Department both retired and still on active service and
all current members of Staff of the Department of Crop
Protection and Environmental Biology, University of Ibadan
for the comradeship.
I also thank members of my extended family, my sister,
Mrs. Kate Morenike Kuye, my brother, Engr. Felix Omolola
Ewete, my cousin, Dr. Augustine Falolu Adeyekun and Mrs.
Victoria Joke Adeyekun, my in-laws Dr. and Mrs. Oyegbile
and Mr. Sehinde Akinbuwa, as well as the Ojajuni and Ibini
families. I also appreciate our family friends, Chief (Dr.) and
Chief (Mrs.) Peter Abu for being there all the time. I thank
our fathers in the Lord, Rev. Frs. Ezekiel Owoeye, Vincent
Alabi and the new Priest, Rev. Fr. Frederick of the Catholic
Chapel, University of Ibadan. I also thank the Aderemi family
of Oke-Igbo, Ondo State.
Finally to my best friend, my jewel, my adviser and love,
Mrs. Agnes Foluso Ewete who had stood by me through thick
and thin over these three" decades plus, I salute your courage
and steadfastness. My children and grandchildren are also
very wonderful-Omoniyi, Ayodele, Olusegun and (queen)
Oluwatoyin, our two grandsons, Olumuyiwa, Olatokunbo and
their mother, Dr. (Mrs.) Tope Ewete (Nee Obademi), you all
give us joy and happiness.
THANK YOU ALL FOR LISTENING.
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References
Aina, 1.0. (1972) The biology of Acanzhomia horrida Germ
(Heteroptera: Coreidae) a pest of fresh cowpea pods. Bull ent.
Soc. Nigeria. 3:85-90.
____ . (1975a) The distribution of coreids infesting cowpea
pods in southwestern Nigeria. Nigeria J. Ent. 1: 119-123.
Akob, C.A and Ewete, F.K. (2007) The efficacy of four locally
used plant materials against Sitophilus zeamais (Coleoptera:
Curculionidae) in Cameroon. International Journal of Tropical
Insect Science 27(1): 21-26. ,
Alamu, O.T. and Ewete, F.K. (2014) The developmental biology of
grain-sucking bug, Stenocoris elegans blote, on upland rice.
International Journal of Insect Science, 6: 57-60.
Akingbohungbe, AE. (1977) Notes on the identity and biology of
the Riptortus spp (Heteroptera: Alydidae) associated with
cowpea in Nigeria. J. nat. Hist., 11: 477-483.
Amason, J.T., Philogene, B.J.R., Donskov, N., Fortier, G.,
McDougall, c., Morris, c., Nozzolillo, c., Lambert, 1.,
Gardner, D. and Hudon, M. (1985) Antifeedant and insecticidal
properties of azadirachtin on European com borer. Entomol.
Exp. Appl. 38: 29-34.
Babarinde, SS. and Ewete, F.K. (2008) Comparative bioactivity of
three Khaya species (meliace). Against Callosobruchus
maculatus Fabricius (Coleoptera: Bruchidae), J. Ent. Res. Soc.
10(1): 27-35.
Catts, E.P. and Goff, M.1. (1992) Forensic entomology in criminal
investigation. Ann. Rev. Ent. 37: 253-272.
Daramola, AM. (1973) The Bionomics of the Kola Weevils,
Sophrorhinus spp. (Coleoptera: Curculionidae) Ph.D. Thesis,
University of Ibadan, pp325.
Egwuatu, R.I. and Taylor, T.A (1977) Studies on the biology of
Acanthomia tomentosicollis Stal. (Hemiptera: Coreidae) in the
field and insectary. Bull. ent. Res., 67: 249-257.
Ewete, F.K. (1978) Insect species and description of damage
caused on okra, Abelmoschus esculentus (L.) Moench. East
African Agricultural and Forestry Journal 44(2): 152-163.
Ewere, F.K. (1984) The immature stages of Oxycarenus gossypinus
Distant (Hemiptera: Lygaeidae). Revue de Zoologie Africaine,
98(3): 596-605.
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- .'
Ewete, F.K., Taylor, T.A and Chheda, H.R (1980) Deterrr.ination
of the period to harvest okra, Abelmoschus esculentus (L.)
Moench, for seed. Ghana Journal Agricultural Science, 13(3):
107-110.' ,
Ewete, F.K .and Osisanya, E.O. (1985) The effect of various diets
(seeds) on development, longevity and fecundity of the cotton
seed bug, Oxycarenus gossypinus Distant (Hemiptera:
Lygaeidae). Insect Science and Its Application, 6(4): 543-545 ..
(1988) Studies on the biology of Oxycarenus
gossypinus Distant (Heteroptera: Lygaeidae). East African
Agricultural and Forestry Journal, 54(2): 79-83. _
Ewete, F.K and Ukwela, U.M. (1991) Aspects of the development,
survival and immature stages of Cletus fuscescens Walker
(Heteroptera: Coreidae) on Amaranthus. East African
Agricultural and Forestry Journal, 57(2): 111-120 .
. Ewete, EK. and Niba, S.A (1994) The life history and damage
caused by Mirperus jaculus Thunberg (Hemiptera: Alydidae)
on cowpea. Journal of African Zoology, 108(4): 407-413.
Ewete, F.K 'and Joda, AO. (1996) The development of Riptortus
dentipes Fab. (Hemiptera: Alydidae) and damage caused on
soyabean. African Crop Science Journal 4(3): 345-350.
Ewete, F.K and Bamigbola, KA (1998) Effects of three natural
product extracts as toxicants against Callosobruchus maculatus
F. (Coleoptera: Bruchidae) infesting bambara groundnut.
Journal of Tropical Forest Resources, 14: 1-8.
Ewete, F.K and Alamu, O.T. (1999) Extracts of three mahogany
species as grain protectants against Sitophilus zeamais
Motschulsky (Coleoptera: Curculionidae). Journal of Tropical
Forest Resources 15: 22-29.
Ewete, F.K, Amason, J.T., Larson, J. and Philogene, B.lR (1996)
Biological activities of extracts from traditionally used
Nigerian Plants against the European com borer, Ostrinia
nubilalis. Entomologia Experimentalis et Applicata, 80(3):
531-539.
Ewete, F.K, Amason, IT., Durst, T. and Mackinnon, S. (2000)
Toxicity of gedunin, piperine and crude extracts of their natural
products on growth, development of Ostrinia nubilalis Hubner
(Lepidoptera: Pyralidae). Discovery and Innovation 12(1&2):
67-72.
Ewete, F.K, Nicol, RW., Hengsawad, V., Sukumalanand, P.,
Satasook, c., Wiriyachitra, P., Isman, M.B., Kahn, Y., Duval,
F., Philogene, B.J.R and Amason, J.T. (1996) Insecticidal
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activity of Aglaia odorata extract and the active principle,
rocaglamide, to the European com borer, Ostrinia nubilalis
Hub. (Lepidoptera: Pyralidae). Journal of Applied Entomology,
120: 483-488.
Greenberg, B. (1991) Flies as forensic indicators. J. Med. Ent., 28:
565-577.
Isman, M.B. (1994) Leads and prospects for the development of
new botanical insecticides. Reviews Pesticide Toxicology 3: 1-
20.
Ivbijaro, M.F.A. (1975) Studies on the bionomics and control of
Balanogastris kolae (Desbrochers) (Coleoptera: Curculio-
nidae). pp 381.
Joda, O.A. (2000) Bioecology and Control of Aspavia armigera
Fabricius (Hemiptera: Pentatomidae) on rice in some major
rice growing areas of Nigeria. Ph.D Thesis, University of
Ibadan, Ibadan, Nigeria, 202 pp.
Odebiyi, J.A. (2004) Understanding and Exploitation of Balance of
Nature in Insect Pest Management. Inaugural Lecture,
University of Ibadan, Ibadan, 30 pp.
Oigiangbe, O.N., Ivbijaro, M.F., Ewete, F.K. and Mutsaers, H.J.W.
(1997) Incidence and damage caused by maize stem borers on
farmers' fields in southwestern Nigeria. African Crop Science
Journal, 5(3): 295-302.
Taylor, T.A. (1974) Insects and Our Environment. Inaugural
Lecture, University of Ibadan, Ibadan, 31pp.
Usua, E.J. (2004) Forensic Entomology and Humanity. A
Symposium to the 35th ESN Annual Conference held at Federal
University of Technology, Akure, October 2004.
Youdeowei, A. (1977) Insects and Nigerians: The Struggle for
Existence. Inaugural Lecture, University of Ibadan, Ibadan,
33pp.
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BIODATAOF
PROFESSOR FRANCIS KOLAWOLE EWETE
Professor Francis Kolawole Ewete was born on 15 May, 1949
in Igboowo Camp, Ode-Ajagba to the family of High Chief
Jacob Erogbonaye Ewete, a native of Igbotako-Osooro in
Okitipupa LGA and Madam Abigael Oyomatan Ewete (nee
Lebi) of Ode-Ajagba in the present Irele LGA of Okitipupa,
Ondo State.
Professor Ewete began his primary school education in
1954 at St. Columbus R.C.M. School, Ojuala in the present
Ese-Odo LGA of Ondo State where his father had sojourned
from the late 1930s. On his parents checking back home in
December 1954, he transferred his schooling to L.A. Primary
School, Ilutitun-Osooro from 1955-1957. On account of his
father's Christian faith, he transferred to St. Augustine
R.C.M. School, Ilutitun-Osooro from 1957-1960 where he
obtained his Primary School Leaving Certificate. He attended
Manuwa Memorial Grammar School (MMGS), Ijuodo in
Okitipupa LGA from 1962-1966 for his West African School
Certificate. and C.M.S. Grammar School, Bariga (formerly
Lagos Anglican Boy's Grammar School) for his Higher
School Certificate from 1967-1968. He was admitted into the
University of Ibadan in September 1969 and obtained his
B.Sc. (Agriculture) with Honours in Crop Science in 1972.
He obtained the Postgraduate Diploma in Crop Protection
having passed with distinction in 1974; M.Phil. (Agric), 1976
and Ph.D., 1984 in the then Department of Agricultural
Biology (now Department of Crop Protection and
Environmental Biology).
Professor Ewete was employed as an Assistant Lecturer at
the Institute of Agricultural Research and Training (IAR&T),
Moor Plantation, Ibadan, 1977-1983. He transferred his'
service to the University of Ibadan on 1 July, 1983 as
Lecturer I. He was promoted Senior Lecturer 1990; Reader
1996 and Professor on October 1999. He has published over
45 research-based journal articles in highly reputable outlets
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"'.'
locally and internationally. He has' successfully supervised
over 40 M.Sc., 5 M.PhiI. and 5 'Ph;D students, two of whom
are already Professors in Nigeria,
Professor .Ewete 'has served the University-in the
following capacities.Assistant Hall Warden, Tafawa Balewa
(Postgraduate) Hall, 1989-1993; Hall Warden, i994-1999-and
Hall Master, 2003-2005; and member of University Senate,
1990 till date. He was appointed Head of Department of Crop
Protection and Environmental Biology, 2005-2008 and Dean,
Faculty of Agriculture and Forestry, 2008-2010. -
Outside the University, he has served as external
examiner to Obafemi Awolowo University" Ile-Ife; Federal
University of Technology, Akure; 'Federal University of
Agriculture, Abeokuta; Olabisi Onabanjo University, Ago-
Iwoye and Walter Sizulu University, Kwazulu Natal, South
Africa. He also served on the panel of Accreditation of
courses at the Faculty of Agriculture in University of Ghana,
Legon and .Kwame Nkrumah University of Science and
Technology, Kumasi, Ghana in 2006. He was a member of
NUC Accreditation team to the University of Calabar,
Federal University of Technology, Owerri; University of
Ado-Ekiti (now Ekiti State University) Ado Ekiti, and Joseph
Ayo'Babalola University, Ikeji Arakeji.
Professor Ewete is a recipient of the Canadian
CIDAINSERC Research Fellowship;' 1992; The Royal
Society Third World Fellowship" UK in 1996; The
MacArthur Foundation Multidisciplinary Team Research
Grant, University of Ibadan, 2009; and The Senate Research
Grant, University of Ibadan.
Professor Ewete is happily married to Mrs. Agnes Foluso
Ewete (nee Akinlogbon). The marriage is blessed with four
children and two grandsons.
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NATIONAL ANTHEM
Arise, 0 compatriots
Nigeria's call obey' .
To serve our fatherland .
With love and strength and-faith .
The labour Of our heroes' past
Shall never be in vain
To serve with heart and might"
One nation bound in freedom
Peace and unity
o God of creation
Direct our noble cause"
Guide thou our leaders right
Help our youths the truth to know
In love and honesty to grow
And living just and true
Great lofty heights attain
To build a nation where peace
And justice shall reign
UNIVERSITY OF mADAN ANTHEM
Unibadan, Fountainhead
Of true learning, deep and sound
Soothing spring for all who thirst
Bounds of knowledge to advance
Pledge to serve our cherished goals!
Self-reliance, unity.
That our nation may with pride
Help to build a world that is truly free
Unibadan, first and best
Raise true minds for a noble cause
Social justice, equal chance
.Greatness won with honest toil
Guide our people this to know
Wisdom's best to service turned
Help enshrine the right to learn
For a mind that Knows is a mind that's free
53
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 IBADAN LIBRARY
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