Informatics Publishing Limited

N. Venugopal Rao ¹, A. S. Reddy ², K. Tirumala Rao ¹

Affiliations
1 Regional Agricultural Research Station, Lam, Guntur 522 034, IN
2 Regional Agricultural Research Station, Nandyal, IN

Abstract

The nymphal parasitism of whiteny, Bemisia tabaci Gennadius due to Eretmocerus serius, Eretmocerus sp. and an aphelinid reached 27.4 and 40.2 per cent while the predators Brumoides suturalis (F), Verania vincta, Menochilus sexmaculatus, Chrysoperla carnea (Steph.), Amblyseiuss pp. were at a level of 10.8 and 17.1 numbers per 10 leaves during January and November respectively. The incidence of fungal pathogens viz. Aspergillus sp., Paecilomyces sp. and Fusarium sp., of whitefly was high during November month by suppressing adults, nymphs and eggs to the extent of 86.6, 19.0 and 39.8 per cent respectively. In line with pest population, the parasites were also Influenced by the rainfall which showed significant negative correlations (r  =  0.4275 and 0.3971 respectively). The temperatures also showed a significant correlation with the parasitism, predatory population and mortality due to fungal pathogens.

Keywords

Bemisia tabaci, Phytoseiids, Fungal Pathogens, Abiotic Factors.

Full Text

   

N. Venugopal Rao ¹, K. Tirumala Rao ¹, A. Sathyanarayana Reddy ¹, Meera Gupta ²

Affiliations
1 Regional Agri. Res. Station, Lam, Guntur - 522 034, IN
2 Central Biological Control Station, Somajiguda, Hyderabad - 500 482, IN

Abstract

The pigeonpea pod borer, Helicoverpa (=Heliothis) armigera (Hbn.) in recent years has been identified as a pest which acquired resistance to many of the commonly used insecticides (Dhingra et al., 1988). The unabated population explosion of this pest since 1986 in Andhra Pradesh confirmed the understanding that even synthetic pyrethroids are quite ineffective against this pest. Studies made by Santharam et al. (1981), Jayaraj et al. (1989) and Sithanantham (1987) indicate that nuclear polyhedrois virus (NPV) can be used to contain this pest at field level. Hence, studies were conducted at the Regional Agricultural Research Station, Lam in collaboration with the Central Biological Control Station, Hyderabad on the utility of NPV against the pigeonpea pod borer.

Keywords

Helicoverpa armigera, Control, NPV, Pigeonpea.

Full Text