Effect of transplanting dates and premature fruit pickings on Helicoverpa armigera Hur. population in two tomato cultivars
1996
Ullah, F. | Khan, A. | Khalil, S.K. (NWFP Agricultural Univ., Peshawar (Pakistan))
Two cultivars of tomato; Tiny Tim (V 56) and Roma were tested for early and late sowing against Helicoverpa (Heliothis) armigera. Late sowing resulted in low number of eggs and larvae but the weight and percentage of sound fruits was also low, while weight and percentage of infested fruits was high. It is, therefore, suggested not to transplant tomato late in the season (April 10). Similarly two cultivars; Tiny Tim (V56) and Big Long (V4) of tomato were sown and tested for the effects of premature fruit pickings on H. armigera population. One to three pickings in comparison with no picking were done. When number of premature pickings were increased from 1 to 3, the number of eggs and larvae decreased, but the weight and percentage of sound fruits did not increase. While the weight and percentage of infested fruits increased. It was concluded that premature pickings would result in additional cost of production with no increase in yield and therefore, is not recommended. In both the experiments Tiny Time (V56) proved to be resistant to H. armigera as compared with Roma and Big Long (V4).
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