Efficiency of the entomopathogenic fungus, Beauveria bassiana (Bals), against Aphis crassivora Koch and Bemesia tabaci, Gennandius

Abstract

: Beauveria bassiana as an entomopathogenic fungi showed high effects on the aphid Aphis crassivora and the white fly Bemesia tabaci infesting cucumber. A dose of 1 mg.ml−1 killed 100% of either insects. Lower doses showed lower effects. Nymphs of the two insects were markedly affected by treatment of the fungi. The total duration and the number of survivors were significantly decreased by an increase in the dose of the pathogen. Latent effects were clearly observed in the resulting adults. Adult longevity, period of reproduction and fecundity were markedly decreased by an increase of B. bassiana dose. The increase in dose of the pathogen increased the resultant winged form of A. crassivora up to 91.7% at 0.5% mg.mr−1.

Influence of Lecanicillium attenuatum on the development and reproduction of the cotton aphid, Aphis gossypii

“…Total fecundity also showed the same trend to reproductive periods. This result agrees with Zaki (1998) in that the reproductive period and fecundity of cowpea aphid were decreased with an increase of spore dose. An application of entomopathogenic fungi, B. bassiana and V. lecanii, significantly reduced the fecundity of insect pests such as legume flower thrips, lettuce aphid and Russian wheat aphid (Ekesi and Maniania, 2000;Fournier and Brodeur, 2000;Wang and Kundsen, 1993).…”

“…Developmental time at each nymphal stage of cotton aphid was not significantly affected by conidial dose but individual instar periods as well as total nymphal time had a tendency to slightly increase in spore-treated aphids compared with controls treated with 0.001% aqueous Tween 80. These results differ from Zaki (1998) who reported that the nymphal period of A. crassivora was markedly decreased with increasing dosage of B. bassiana.…”

“…Ekesi and Maniania (2000) and Zaki (1998) reported that longevity of legume flower thrips (Megalurothrips sjostedti) and cowpea aphids (Aphis crassivora) were decreased by increasing the dose of Metarhizium anisopliae and B. bassiana conidia, respectively. They demonstrated that the high infection rates by entomopathogenic fungi could reduce the life span of pests which could lessen crop damage.…”

“…Insect reproduction and longevity are affected by various factors such as temperature (Kocourek et al, 1994;Kersting et al, 1999), nutritional quality (Nevo and Coll, 2001), pesticides (Rongai and Cerato, 1996), and entomopathogens (Sait et al, 1994;Fargues et al, 1991). Although reproduction, longevity and development time are key factors in aphid population dynamics, information is lacking on the influence of entomopathogenic fungi on nymphal development time, insect fecundity and life span (Fargues et al, 1991;Mulock and Chandler, 2001;Zaki, 1998). It is important to understand the influence of the pathogen on the developmental period and reproduction of an insect pest to develop a successful biological control program.…”

Paecilomyces niveus Stolk & Samson, 1971 (Ascomycota: Thermoascaceae) as a pathogen of Nasonovia ribisnigri (Mosley, 1841) (Hemiptera, Aphididae) in Brazil

“…However, N. ribisnigri is resistant to some insecticides (Martin et al, 1996;Rufingier et al, 1997;Barber et al, 1999;Dedryver et al, 2010). One alternative to the use of insecticides to reduce the occurrence of this pest is integrated pest management involving the application of entomopathogenic fungi (Dorschner et al, 1991;Zaki, 1998;Steinkraus, 2006;Asman, 2007;Díaz et al, 2010;Scorsetti et al, 2010Scorsetti et al, , 2012Skinner et al, 2012). Fungal pathogens are the most important pathogens of aphids and epizootics are frequently observed that often rapidly reduce aphid populations (Steinkraus, 2006).…”