D. K. Banyal

Integrated Management of Whitefly, Bemisia tabaci (Gennadius) and Potato Apical Leaf Curl Virus in India

This paper reviews the importance of Potato apical leaf curl virus (PALCV) in India, the biology of its major vector Bemisia tabaci and possible control measures of PALCV and B. tabaci. PALCV has appeared as a new problem in potato growing areas of northwestern plains of India. The first report of PALCV was made from Hissar around 2000. PALCV is a whitefly (B. tabaci) transmitted viral disease and the symptoms are manifested primarily in the form of upward or downward curling of leaves, with 40–75% infection being recorded in cultivars grown in the Indo-Gangetic Plains of India. B. tabaci is a polyphagous pest that feeds on numerous fibre (particularly cotton), food, vegetable and ornamental plants. B. tabaci produces many generations in a year and reaches high population densities. To check the disease incidence, whitefly suppression using imidacloprid either as seed treatment or as foliar application early in the season is recommended. To minimize within-field spread of viruses, removal of virus-infected plants is suggested. Application of mineral and vegetable oils has been found to inhibit virus transmission and possibly can help to avoid difficulties with insecticide resistance in whiteflies.

Resistance of pea genotypes in relation to sporulation by Erysiphe pisi

Abstract Resistance of pea ( Pisum sativum ) genotypes in relation to sporulation, as represented by numbers of ‘conidiophores-bearing-conidia’ per colony, of Erysiphe pisi on detached leaflets was studied. Many fewer conidiophores-bearing-conidia per colony were produced on highly resistant and resistant genotypes as compared with other genotypes. Moderately resistant and moderately susceptible genotypes could be separated from highly resistant to resistant and from susceptible to highly susceptible genotypes by significant differences in conidiophore counts. A general idea of resistance/susceptibility of pea genotypes may be obtained by recording sporulation on detached leaflets and this information could be useful in supplementing and/or confirming field reactions of pea genotypes. An indication of existence of pathogenic types in E. pisi was also obtained.