The present study was conducted with the object of studying the population fluctuations of &mist:3 (abaci on four vegetable crops; pepper,okra,eggplant and cabbage, as affected by three weather factors; daily -mean temperature, night mean temperature and daily mean relative humidity and to evaluate these hosts for the &taboo" infestation throughout two sucrimcsive summer seasons of 2001 and 2002 at Qualyobia Govemorate.Results can be summarized as follows: Population of eggs and nymphs of B. tabad were greatly affected by the host plant as well as the combined action of the three tested weather factors rather than the single effect of each factor. Pepper was the least infested (8.43 & 11.25 eggs /10 ins.2 and 5.28 & 10.55 nymphs /10 ins.2 ), the cabbage was the most infested (94.25 & 100.53 eggs/10 ins.2 and 80.75 & 88.53 nymphs/10 ins? ), okra harboured (21.4 & 25.4 eggs/10 ins.2 and 15.05 & 23.1 nymphs/10 ins!), while eggplant harboured (81.58 & 78.85 eggs/10 ins.2 and 62.23 & 69.43 nymphs/10 ins.2 ), respectively.