International Journal of Farm Sciences 1(2) :45-55, 2011 Exploitation of heterosis for yield and its contributing traits in tomato, Solanum lycopersicum L SANTOSH KUMARI and MANISH K SHARMA* Seed Technology and Production Centre *Department of Vegetable Crops Dr YS Parmar University of Horticulture and Forestry , Nauni , Solan, HP ABSTRACT Heterosis for yield and other component characters of 45 F 1 hybrids of tomato derived from the crosses between 15 lines and 3 testers through line x tester technique was studied. Maximum and significant heterosis in favourable direction was observed for yield, fruit number, plant height and fruits per cluster. Heterosis was appreciable in all hybrids, but was more in four hybrids viz Sioux x FT-5, S-1001 x Solan Vajr, EC-521041 x FT-5 and S-1001 x EC-15998. Keywords: Heterosis, yield, tomato INTRODUCTION Tomato (Solanum lycopersicum L) is one of the most important, popular and widely grown vegetables in the world. It is the most remunerative cash crop of mid hills of Himachal Pradesh. The pace with which the F 1 hybrids of tomato are gaining popularity, it is demanding now to obtain such hybrids in public sector also, which have excellent quality and yield stability. The average fruit yield in tomato is very low as compared to Japan. Thus there is a vast scope for its improvement which can be achieved through breeding high yielding varieties/hybrids. Therefore, it was planned to develop high yielding tomato hybrids along with other contributing traits suitable for growing under hill conditions. MATERIAL AND METHODS The experimental material consisted of 15 lines viz EC-31761, EC-521067, EC-521041, EC-521054, EC-1914, EC- 538146, EC-5888, EC-524087, EC- 521051, EC-144336, EC-13736, EC- 60531, Sioux, S-4 and S-1001 was crossed with three testers viz FT-5, Solan Vajr and EC-15998 in line x tester fashion to obtain forty five hybrid combinations in summer 2007 at the vegetable research farm of the Department of Vegetable Science, Dr YS Parmar University of Horticulture and Forestry, Nauni, Solan. Crosses were made manually using the standard procedure of hand emasculation and pollination. F 1 s were evaluated along with their parents for various horticultural traits