CONTROL MEASURES OF TOMATO YELLOW LEAF CURL VIRUS (TYLCV) UNDER FIELD CONDITIONS

Abstract

The present work was conducted to survey the natural infection percentage by TYLCV disease, disease severity and survey of population density of whitefly Bemisia tabaci during summer and Nili plantations in season 2000 at EI-Riad and Qullien districts, Kafr EI-Sheikh Governorate as well as identification of TYLCV disease isolated tl•om naturally infected tomato plants and also the present study aims to reach the highest degree of control this virus with non-traditional methods and with least amount ot' insecticidal pollution of the environment.

The results of the present work can be summarized 111 the following points: Part 1: Survey of TYLCV natural infection, population density of whitefly B. wbaci and disease severity in summer and Nili plantations: I. Summer J>lantation:

During summer plantation, the whitefly began to appear in February, then it increased gradually to reach the maximum population in May. The natural infection ofTYLCV disease was began to appear (5%) in March and reached (I 0%) in May.

2. Nili plantation:

During Nili plantation, the whitefly began to appear on the tomato plants with high densities in June, then it increased gradually during July -.Z. and increased sharply in August to reach its peaks in September. The

natural infection of TYLCV was I 0-15% in June and increased gradually (65%) during July and reached epidemic proportion (90, 95%) in September and October in the two districts (Qulline and EI-Riad).