STUDY ON COMBINING ABILITY AND HETEROSIS IN TOMATO LINES

A Thesis Submitted to the Department of Horticulture Sher-e-Bangla Agricultural University, Dhaka In partial fulfillment of the requirements for the degree of MASTER OF SCIENCE HORTICULTURE SEMESTER: JULY-DECEMBER, 2014

The general combining ability was the best general combiner for plant height at last harvest, number of flower cluster per plant, fruit size exhibited highest GCA effect for individual fruit weight, number of seed per fruit, P 6 5 showed highest GCA effect for number of fruit per plant, P 2 and P 8 were the best general combiner for earliness and parent P showed highest significant positive GCA effect for fruit yield per plant although fruit size of this parent is not good enough. The highest SCA effect and heterosis over mid parent for earliness was observed in the cross combinations P × P 8 1 which also showed best heterosis over mid parent for earliness, fruit breadth and number of seed per fruit. Cross combination P 8 × P showed the highest SCA effect and higher mid parent heterosis for the highest plant height at last harvest and for plant height at last harvest; flower cluster per plant and TSS% ; P 7 × P 9 9 showed the highest SCA effect and heterosis for number of flower per cluster; P number of fruits per plant; P 5 × P 7 for improvement of individual fruit weight; P 5 × P for number of seed per fruit and mid parent heterosis for fruit breadth; the highest SCA and mid parent heterosis observed in P for fruit length; P 4 × P 8 for fruit breadth; P 2 × P 6 for number of locules; P 1 8 × P showed the highest SCA and heterosis over mid parent for increasing pericurp thickness; P 1 × P 6 5 showed the highest SCA and heterosis for fruit yield per plant. Therefore earliness, higher yield and higher quality the hybrids P , P 1 × P 6 , P 2 × P 6 , P 2 × P 8 , P 4 × P 8 P 5 × P 7 , P 6 × P 9 , P 7 × P 8 may be selected for further trial. 6 × P 9 2 1 × P × P 9 7 8 5