Effect of combining Metarhizium anisopliae (Ascomycota: Hypocreales) and Cheilomenes sexmaculata Fabricius (Coleoptera: Coccinellidae) on population of Aphis gossypii (Hemiptera: Aphididae)
Paper ID : 1450-24IPPC (R3)
Authors
1Faculty of Agriculture, Department of
Crop Protection, Vali-e-Asr University of
Rafsanjan, Rafsanjan, Iran
2گروه گیاهپزشکی، دانشکده کشاورزی، دانشگاه ولی عصر رفسنجان
3گروه گیاهپزشکی، دانشکده کشاورزی، دانشگاه ولی عصر رفسنجان
Abstract
Among different biological control agents coccinellids and entomopathogenic fungus have been used for control of aphids on a variety of crops. Cheilomenes sexmaculata Fabricius (Coleoptera: Coccinellidae) and the entomopathogenic fungus Metarhizium anisopliae (Ascomycota: Hypocreales), have been considered against aphids. It is necessary to use two or more biological agents to achieve effective control levels in biological control of Aphis gossypii (Hemiptera: Aphididae). So this is important to determine the effect of interaction between biological control agents that share host to assess their efficiency when they use simultaneously. This study aimed to determine the interaction between M. anisopliae and C. sexmaculata for control of A. gossypii. All experiments were done at laboratory conditions, at 25±1°C, 75±5% RH and photoperiod 16:8 h. All experiments were conducted on cucumber plants with an average leaf number of five infected with nymph of A. gossypii. Cucumber plants were treated with 2 ml of 3.31×103 spore ml-1 of M. anisopliae and control was sprayed with 0.02% sterile aqueous Tween 80. Effect of the presence of conidia of entomopathogenic fungi on the choice of oviposition site by C. sexmaculata revealed that females prefer the control compared to treated plant, and also oviposition rate significantly reduced in treated plant. The effect of co- application of M. anisopliae with a pair of C. sexmaculata on population of A. gossypii revealed that using simultaneously of coccinellid and entomopathogenic fungi have an additive effect, and reduced aphid population in treated plant about 97%, compared to use of each agent. The result demonstrated that it is possible to use simultaneously two biological agents, C. sexmaculata and M. anisopliae, in integrated management program of A. gossypii. This possibility needs to investigate the effect of aphids treated with pathogenic fungi M. anisopliae on biological parameters of C. sexmaculata and field experiments to investigate the combined effect of these two biological control agents under natural conditions.
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