| Weather pattern is of mild and moist characteristics in Yunnan Province, southwestern China all the year round. Either sucking insect pests or their diseases attributed to fungal pathogens commonly occur under such circumstances, which also are favorable to control of insect pests by formulations of fungal biocontrol agents. In Yunnan Province, however, it is weak in microbial control of insect pests due to lack of basic and applied research on fungal biocontrol agents. Based on previous achievements in our laboratory, the present study was aimed at 1) survey of entomopathogenic fungi naturally infecting aphids that usually infest crops or economically important plants in Kunming, Yunnan; 2) evaluating efficacies of emulsifiable formulations of Beauveria bassiana SG8702 and Paecilomyces fumosoroseus Pfrll6 alone or together with sublethal dosages of imidacloprid for control of whiteflies and aphids under greenhouse or field conditions. The results are summarized as follows:Diversity and frequencies of entomopathogenic fungi naturally infecting aphids in Kunming, Yunnan. Yellow traps were set up to trap migratory alates from air to potted cabbage or wheat plants placed on the top-floor platform of a six-floor building on campus of Yunnan Agricultural University from July 2002 to Feburary 2004. At the time of daily visit, all alates tranpped on to the plants were collected back to laboratory and individually reared for 7 days on detached cabbage leaves in Petri dishes or wheat seedlings in glass tubes. Alates killed by mycoses during the period of rearing were individually examined for fungal identification and frequency estimates of fungal pathogens involved. A 17-month trapping survey in the three years resulted in a total capture of 8159 alates, including 4095 alates of Myzus persicae, 1848 Brevicoryne brassicae, 1741 Sitobion avena, 150 Rhopalosiphum padi, 127 Lipaphis erysimi, 114 Acyrthosiphon pisum, and 84 Pemhigus sinobursariu. Of those, 2673 alates were found dying of mycosis during the 7-day period of rearing, taking a proportion of 32.76% in total. Fungal pathogens involved in the mycosis-killed alates included Entomphthorales (89.15%) and Hyphomycetes (10.85%). Among the 2383 alates killed by Entomophthorales, 1830 were attributed to Pandora neoaphidis, 474 to Entomophthora planchoniana, 42 to Conidiobolus obscurus, 29 to Zooththora radicans,and only 8 to Neozygites fresenii. The first four Entomophthorales are obligate aphid pathogens and another has a wide range of insect hosts commoly including aphids. Three hyphomycetous species were also identified in 290 alate cadavers, including the commonly seen fungal biocontrol agents Beauveria bassiana in 261 and Paecilomyces fumosoroseus in 18, and the possibly opportunistic pathogen Aspergillus flavus in 11. Based on frequencies of all the fungal pathogens appeared in the trapped alates, P. neoaphidis was most predominant with a frequency of 22.43% seen in all the trapped alates and 68.46% in those infected. All the alates infected with the Entomophthorales died within the first five days while individually reared, with the cumulative mortalities of 3.23, 25.98, 75.16, and 97.86% on days 1-4 after capture respectively, and had a mean latent period of 2.98 (?0.81) days. The Hyphomycetes-infected alates died mostly on days 3-5 after capture with the cumulative mortalities of 0.34, 4.83, 41.38, 81.38, and 98.28% respectively and had a mean latent period of 3.74 (?0.86) days. The latent periods differed significantly between the two groups of fungal pathogens infecting the alates (/ = 14.98, PO.01).Efficacies of emulsifiable formulations of B. bassiana and P. fumosoroseus conidia for control of whiteflies on lettuce under greenhouse conditions. Mineral oil-based emulsifiable preparations of B. bassiana (Bb) and P. fumosoroseus (Pfr) conidia were separately applied alone or together with low rates of imidacloprid 10% WP at 4.7% (Im 1), 14.0% (Im 2), and 23.3% (Im 3) of its recommended application rate respectively against the greenhouse whitefly, Trialeuro...
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