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Item Biological control agents of aphids (Homoptera: Aphididae) on potatoes (Solanum tuberosumL) in Kenya(2010) Machangi, J. M.; Gitonga, L. M.; Nderitu, J. H.; Maniania, N. K.; Kabira, J. N.A field survey was conducted in four major potato growing areas in Kenya (Kiambu, Nyandarua, Meru and Molo Districts) during January and February, 2008 (short rains crop) and June 2008 (long rains crop) to determine the occurrence of predators, parasitoids and pathogens of the aphids Myzus persicae Sulzer and Aphis gossypii Glover in potato crops. In each of the four areas, 30 potato farms distributed in different parts of the survey area were selected at random for the surveys. Insects collected were brought to the laboratories at the International Centre of insect physiology and Ecology (icipe), Nairobi, for identification and fungal infection. For isolation of fungal pathogens, dead aphids were transferred on moist filter paper placed on sterile Petri dishes to allow the growth of the fungus on the surface of the cadaver, after which fungus was transferred on artificial media for isolation. Four aphid species, M. persicae, A. gossypii, Macrosiphum euphorbiae Thomas and Aulacorthum solani Kaltenbach were identified in all the four survey areas. Sixteen predator species of the aphids were identified. The most prevalent were the ladybeetles Harmonia axyridis (Pallas) and Hippodamnia convergens Guérin-Méneville (Coleoptera: Coccinellidae), followed by the minute pirate bugs, Orius spp. (Heteroptera: Anthocoridae) and the aphid eating gall midge Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae). Three hymenopteran parasitoid species (Braconids followed by Chalcids then the Ichneumonids) and four fungal pathogen species, Beauveria bassiana Balsamo (Ascomycota: Hypocreales), followed by Verticillium lecanii Zimmermann (Hypocreales: Incertae sedis), Metarhizium anisopliae (Metsch.) Sorokin (Deuteromycotina: Hyphomycetes) then Pandora neoaphidis (Remaudière &Hennebert) Humber (Zygomycetes:Entomophthorales) were identified in all four areas of the field survey.Item Performance of a semiochemical-baited autoinoculation device treated with Metarhizium anisopliae for control of Frankliniella occidentalis on French bean in field cages(Karatina University, 2011-12-16) Niassy, S.; Maniania, N. K.; Subramanian, S.; Gitonga, L. M.; Ekesi, S.The performance of an autoinoculation device was evaluated in field cage experiments for control of Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), in French bean, Phaseolus vulgaris L. var. Samantha (Fabaceae). Treatments consisted of a fungus-treated device with and without semiochemical (Lurem-TR), and a fungusfree device as control; the fungus used was Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae). The overall mean number of conidia acquired by a single insect was higher in the fungus-treated semiochemical-baited device than in the device without 10 × 0.6 ± semiochemical: 5.04 10 × 0.4 ± vs. 2.24 conidia per insect. The overall thrips mortality was also higher in the semiochemical-baited device than in the device without the 3.5%. Conidial viability was not ± 3.9 vs. 41.7 ± semiochemical: 59.3 affected in the M. anisopliae-treated device without days after treatment, whereas it was considerably semiochemicals, 7 days post-inoculation 1.1%, 2 and 7 ± 1.3 to 6.5 ± decreased – from 81.0 – in the M. anisopliae-treated semiochemical-baited device. Thrips mortality was positively correlated with M. anisopliae conidial viability, and conidial viability was negatively correlated with conidial acquisition. This suggests that the semiochemical volatiles reduced the conidial viability, which in turn resulted in significant reduction in thrips mortality, despite the highest conidial acquisition in the semiochemical-baited fungus-treated device. Thrips density per plant was significantly reduced in both fungus-treated 1.7 adults per plant; without ± treatments (with semiochemical: 8.7 1.4 adults per plant) compared with the fungus-free ± semiochemical: 6.6 2.6 adults per plant). These results demonstrate the ± control (19.8 potential for an autoinoculation device strategy for the control of thrips, particularly in screenhouses.