Effectiveness of Isolates of Metarhizium anisopliae against Aphis gossypii (Hemiptera: Aphididae) on Capsicum annum and Solanum melongena

Abstract

The virulent of five Metarhizium anisopliae isolates (PR1, GT2, TFFH3, GJ4 and HSAH5) at the concentration of 1 x 107 conidia mL-1 against Aphis gossypii reared on Capsicum annum (chilli) and Solanum melongena (brinjal) was evaluated in vitro by leaf dipping method. There was a significant different between isolates on the virulent against first nymphal instar of Aphis gossypii for both crops (F = 341.38, P < 0.01). The PR1 and GJ4 isolates of M. anisopliae were the most virulent with PR1 showing mortality of 99 and 100% on C. annum and S. melongena respectively. The LC50 of PR1 isolate on the aphid reared on chilli (3.76 × 105) was lower than aphid reared on brinjal (9.68 x 105). Among the selected isolates, PR1 treatment on chilli had 18.6 times lower LC50 (3.76 × 105 conidia/mL) compared to GJ4 on chilli (7.00 × 106 conidia/mL). The virulent of PR1 assessed against all life stages of aphid showed significant difference between life stages of A. gossypii (1st, 2nd, 3rd, 4th and adult) (F = 163.52, P < 0.01) with the most susceptible was first instar follow by its subsequent stages and the least susceptible was adult stage. The result indicates that the isolate PR1 has potential as biological control agent of the aphid and application at the earlier stages should be utilized in controlling the aphid. © 2022 Friends Science Publishers