Population dynamics of the vector of pigeon pea sterility mosaic disease, Aceria cajani Channabasavanna

Abstract

Studies on the population dynamics of the vector, Aceria cajani on pigeonpea revealed that the trifoliate leaf and vegetative buds of upper canopy harboured relatively more number of mites (46.89 and 56.80 mites per trifoliate leaf, respectively) when compared to trifoliate leaf and vegetative buds of middle (29.17 and 39.41 mites per trifoliate leaf, respectively) and lower canopies (16.63 and 23.40 mites per trifoliate leaf, respectively). Amongst different portions of leaflet, maximum number of mites preferred basal quarter of leaflet (19.27, 14.80 and 10.80 mites/trifoliate leaf in top, middle and lower canopies, respectively) followed by middle (15.63, 11.93 and 9.40 mites/trifoliate leaf in top, middle and lower canopies, respectively) and terminal portions (11.93, 6.80 and 4.70 mites/trifoliate leaf in top, middle and lower canopies, respectively). On different aged leaves, maximum number of mite population was observed on younger leaves (62 mites per trifoliate leaf) followed by middle aged leaves with (40 mites per trifoliate leaf) and older leaves (23 mites per trifoliate leaf). Maximum number of mites was recorded at 43rd SMW (30.21 mean mites/trifoliate leaf) and the minimum number of mites was recorded at 34rd SMW (2.09 mean mites/trifoliate leaf). The difference in the population of mite during different meteorological weeks may be due to epidemiological factors.