IMPACT OF WEEDING ON WHITEFLY, Bemisia tabaci (Genn.) POPULATION ON OKRA CROP

Studies on the impact of weeding on population of whitefly, Bemisia tabaci (Genn.) on okra crop were carried out at Private Farm near Kandiaro, district Naushahro Feroze during November, 2004 to February, 2005. Seeds of Subzpari variety were sown on 10 th November, 2004 in RCBD having 4 treatments and 5 replications. The treatments were Complete weeding, Dicotyledonous weeds removed, Monocotyledonous weeds removed and Weedy check. Whitefly population was recorded on weekly basis on okra and weed species as well. Results showed that whitefly appeared on all species of weeds and main crop as well. The most preferred weeds were Cyperus rotundus and Portulaca oleracea followed by Polygonum plebejum, Trianthema monogyna, Cynodon dactylon, Digera arvensis, and Corchorus antichorus with the population of 1.09 ± 0.06, 1.08 ± 1.11, 0.93 ± 0.07, 0.87 ± 0.05, 0.86 ± 0.05, 0.78 ± 0.06 and 0.53 ± 0.58 per plant, respectively. The maximum per leaf population (14.92±2.68) was recorded in the weedy check plots followed by Monocotyledonous weeds removed (8.48 ± 1.86), Dicotyledonous weeds removed (6.59 ± 1.50) and All weeds removed (4.57 ± 1.05). Analysis of variance showed significant differences in population among the treatments. However, non-significant differences were recorded among the populations on C.