Bionomics and population dynamics of Bemisia tabaci on subabul (Leucaena leucocephala).

摘要

Leucaena leucocephala (subabul) has been recently reported as a host plant of the polyphagous whitefly Bemisia tabaci (Gennadius) from India. A study was carried out on the population dynamics of this whitefly on leucaena for two years and it revealed that its populations reached a peak (121.58 and 134.83 adults per two leaves) in September. The spatial distribution pattern revealed that it is always an aggregated dispersion (Taylor's Power Law) in all the strata but more aggregation in the middle leaves (b=3.123). Linear association between population and weather factors revealed that maximum and minimum temperature had a significant positive correlation (r=0.60, 0.54). The sex ratio in the field varied from 1:1.9 to 1:4.9 (male: female). The present observations indicate that incidence of B. tabaci on L. leucocephala, is an adaptation to a suitable host so as to survive during the winter season when the lowest temperature is about 2-4 degrees C.