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1998

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Cost Of Tsetse Trapping Using The Ng2g Trap: A Case Study In Kenya, George Tombe Lako Jan 1998

Cost Of Tsetse Trapping Using The Ng2g Trap: A Case Study In Kenya, George Tombe Lako

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In a study to determine the costs of tsetse trapping in terms of construction materials, labour, transport and maintenance, two hundred forty-six traps used to control Glossina pallidipes in an area of 100 square kilometres at Nguruman, Kenya were evaluated from November 1990 to July 1992. The total cost of materials, labour and servicing per trap per year, was US$ 30.6 which, at that time was equivalent to 1071 Kenya shillings. ©1998ICIPE.

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Effect Of Species, Age, And Sex Of Tsetse On Response To Infection By Metarhizium Anisopliae, Nguya K. Maniania, Adedapo Odulaja Jan 1998

Effect Of Species, Age, And Sex Of Tsetse On Response To Infection By Metarhizium Anisopliae, Nguya K. Maniania, Adedapo Odulaja

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Laboratory studies were carried out to determine the effect of sex and age on the susceptibility of tsetse, Glossina morsitans morsitans and G. m. centralis, to the entomopathogenic fungus, Metarhizium anisopliae. Both species of host flies were susceptible to fungal infection. Female flies were generally more susceptible than male flies. Three host ages (40, 20, and <1 day-old) were used; the youngest group was most resistant to fungal infection. Interactions between species, sex and age were significant on many occasions. Age usually accounted for the largest variability in mortality, followed by sex. All flies of age 40 days died between 7 and 8 days after infection whereas some of the younger flies, especially age 0, lived longer than 10 days. Log10 day probit (LDP) mortality regressions fitted well to most of the data sets. LDP slopes were significant and high, ranging between 4.3 and 12.8, indicating a generally high mortality rate of increase over days. The slopes differed significantly between species, sexes, and ages, but grouping by age was more intra homogeneous than by species or sex. The 50% lethal time mortalities (LT50) ranged between 4 and 7 days for age 0, 3 and 6 days for age 20, and about 5 days for age 40. Corresponding ranges of the LT95 were 8 to 20, 5 to 10, and 6 to 7 days for ages 0, 20 and 40, respectively. The significance of these results in the fungal disease transmission by tsetse is discussed.

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Brood Guarding Behavior And Life History Characteristics Of Goniozus Indicus Ashmead (Hymenoptera: Bethylidae), A Larval Ectoparasitoid Of Lepidopteran Stemborers, Keiji Takasu, William A. Overholt Jan 1998

Brood Guarding Behavior And Life History Characteristics Of Goniozus Indicus Ashmead (Hymenoptera: Bethylidae), A Larval Ectoparasitoid Of Lepidopteran Stemborers, Keiji Takasu, William A. Overholt

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Brood guarding behavior and life history characteristics of Goniozus indicus Ashmead (Hymenoptera: Bethylidae) were examined in the laboratory. Longevity was increased when females were provided host frass, and females reared in association with hosts lived longer than females maintained separately from hosts. Females that were allowed free access to hosts oviposited at intervals of one to eight days and never parasitized more than one host per day. Females laid 5-25 eggs per host, and life time fecundity was 15-52 eggs at 25°C, 7-60 eggs at 28°C, and 5-25 eggs at 31°C. Females exhibited egg guarding behavior, remaining with the hosts …

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The Effects Of A Dna Virus Infection On The Reproductive Otential Of Female Tsetse Flies, Glossina Morsitans Centralis And Glossina Morsitans Morsitans (Diptera: Glossinidae), Rosemary C. Sang, Walter G.Z.O. Jura, Leonard H. Otieno, Richard W. Mwangi Jan 1998

The Effects Of A Dna Virus Infection On The Reproductive Otential Of Female Tsetse Flies, Glossina Morsitans Centralis And Glossina Morsitans Morsitans (Diptera: Glossinidae), Rosemary C. Sang, Walter G.Z.O. Jura, Leonard H. Otieno, Richard W. Mwangi

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Reproductive anomalies associated with the tsetse DNA virus infection in the female tsetse hosts, Glossina morsitans centralis Machado and Glossina morsitans morsitans Westwood, inoculated with the virus during the 3rd instar larval stage were studied and the data compared to those obtained from the control females injected with sterile physiological saline. Virus infected flies had significantly longer first and second pregnancy cycles (P<0.0001) and produced pupae that were of significantly less weight in milligrams (P<-0.0001) compared to controls. Transmission of the virus to progeny was not absolute and only 21% of G. m. centralis and 48% of G. m. morsitans first progeny flies from infected females developed salivary gland hypertrophy as a result of transmission from mother to progeny. The virus infected females produced significantly fewere pupae compared to the controls during the experimental period (P<0.00001).

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Suitability Of Busseola Fusca And Sesamia Calamistis (Lepidoptera: Noctuidae) For The Development Of Two Populations Of Cotesia Sesamiae (Hymenoptera: Braconidae) In Kenya, A. J. Ngi-Song, W. A. Overholt, R. Stouthamer Jan 1998

Suitability Of Busseola Fusca And Sesamia Calamistis (Lepidoptera: Noctuidae) For The Development Of Two Populations Of Cotesia Sesamiae (Hymenoptera: Braconidae) In Kenya, A. J. Ngi-Song, W. A. Overholt, R. Stouthamer

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The suitability of Sesamia calamistis Hampson and Busseola fusca (Fuller) for the development of two geographical populations of Cotesia sesamiae (Cameron) was examined in the laboratory. One population of the parasitoid was collected from the coast of Kenya and the other from the inland. Both populations of the parasitoid could develop on S. calamistis. On B. fusca, the inland population of C. sesamiae was able to develop, while the population from the coastal area of Kenya was encapsulated. Mating studies revealed that the two parasitoid populations were partially reproductively isolated. Unidirectional incompatibility, possibly caused by the Wolbachia infection, was observed …

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Isozyme Diversity In Vigna Vexillata (L.) A. Rich (Fabaceae) Complex, M. Garba, R. S. Pasquet Jan 1998

Isozyme Diversity In Vigna Vexillata (L.) A. Rich (Fabaceae) Complex, M. Garba, R. S. Pasquet

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An electrophoretic comparison of variation at 32 isozyme loci was performed for 122 Vigna vexillata and 3 V. lobatifolia accessions. The results do not fit the present delimitation of taxa. According to the results obtained during this study, Vigna lobatifolia could be included within V. vexillata, and both Asian and West African taxa could deserve a subspecific rank within V. vexillata. Considering only Africa, some similarities between the organization of the gene pools of V. vexillata and V. unguiculata have been found.

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Morphological Study Of Cultivated Cowpea Vigna Unguiculata (L.) Walp. Importance Of Ovule Number And Definition Of Cv Gr Melanophthalmus, Rémy Stéphane Pasquet Jan 1998

Morphological Study Of Cultivated Cowpea Vigna Unguiculata (L.) Walp. Importance Of Ovule Number And Definition Of Cv Gr Melanophthalmus, Rémy Stéphane Pasquet

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More than 400 cultivated cowpea accessions were studied using 29 morphophysiological characters. The analysis of data contrasts evolved cultivars and more primitive cultivars (and wild forms) according to seed size on the one hand and early and late flowering (under inductive conditions) on the other hand. The latter character is markedly correlated with ovule number. Photosensitive and early-flowering photoindependent cultivars have 11-17 ovules per pod and late flowering photoindependent cultivars have 16-25 ovules per pod. The analysis leads to assigning the accessions studied to the following different cultigroups: cv gr Unguiculata, cv gr Sesquipedalis, cv gr Biflora and cv gr …

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Olfactory Responses Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) To The Monitor Lizard Varanus Niloticus Niloticus, M. M. Mohamed-Ahmed Jan 1998

Olfactory Responses Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) To The Monitor Lizard Varanus Niloticus Niloticus, M. M. Mohamed-Ahmed

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Visual and olfactory responses of Glossina fuscipes fuscipes Newstead to the monitor lizard, Varanus niloticus niloticus Laurenti were studied using various catching devices near Lake Victoria, Kenya. Electric nets baited with visible lizards caught more males (x2.1) and significantly more females (x2.0) than unbaited nets. Lizards concealed in electrified black Pvc pipe models, simulating the shape and size of a monitor lizard, increased significantly the catches of tsetse by 2.1 times. Fresh lizard urine dispensed at an evaporation rate of 500 to 1000 mg/h also increased significantly the catches of flies at biconical traps, electrified models and electric nets. Identification …

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