Isolates of Beauveria bassiana (Balsamo) Vuillemin, Paecilomyces farinosus (Holm ex SF Gray) Brown and Smith and Verticillium lecanii (Zimmermann) Viegas were evaluated for their pathogenicity to adults, eggs, first and third instars of silverleaf whitefly, Bemisia argentifolli (Bellows and Perring) (Homoptera: Aleyrodidae). Conidial dilutions were prepared in 0.05% Tween® and leaves treated by immersion in these suspensions. Assessments of nymphal infection were made 2, 3, 5, 7, and 10 days post-treatment. Infection rates in adults and eggs were made 14 days post-treatment. All isolates were pathogenic to nymphs and adults. None of the isolates were pathogenic to eggs. Isolates L3444 (P. farinosus) and L3009 (B. bassiana) were the most pathogenic to first instars and adults with LC50 and LC90 values of 7.3 × 104 and 3.1 × 106 conidia/ml, and 1.3 × 106 and 1.0 × 107 conidia/ml, respectively. Isolate FR20 (V. lecanii) was the most pathogenic to third instars with LC50 and LC90 values of 4.8 × 103 and 7.4 × 105 conidia/ml, respectively. Results imply that L3444 and L3009 are the most efficient isolates, based on their pathogenicity to first instars and adults. Results are discussed in relation to using fungi for management of silverleaf whitefly in greenhouses.

Among the eight entomopathogenic fungi tested against the termite, Odontotermes obesus (Rambur), five fungal pathogens viz., Beauveria bassiana (Bals.) Yuil, Metarhizium anisopliae (Metsch.) Sorokin var. anisopliae, M. flavoviride Gams Rozsypal var. minus, Paecilomyces lilacinus (Thom) Samson and P. fumosoroseus (Wize) Brown & Smith, were pathogenic. Three other fungal pathogens viz. Verticillium lecanii Zimm, Paecilomyces farinosus (Holm, ex Gray) and Nomuraea rileyi (Farlow) were not pathogenic. B. bassiana was the most effective pathogen against termites, followed by M. anisopliae, M. flavoviride, P. lilacinus and P. fumosoroseus. Workers minor, of the three morphogenetic forms of O. obesus, were the most susceptible, followed by workers major and soldier caste. Bioassay on isolates of two most virulent termite pathogens, B. bassiana and M. anisopliae revealed that B. bassiana isolate Bapatla was the most effective fungal pathogen with the lowest LC50 (9.98 × 104 conidia/ml)