LAUSR

ABSTRACT Heterosis breeding is used to improve yield quantity and quality of Tomato (Solanum lycopersicum L.) because traditional methods cannot be used to achieve this goal. A Line × Tester design was used to evaluate standard heterosis to increase growth, yield, and quality by identification of unique cross-combinations with desirable heterosis. Ten parents with three testers and 30 hybrids were evaluated from Sept. 2012 to Mar. 2014. Heterotic vigor was present for growth and yield characters among hybrids. Significant differences for all characters indicated the presence of genetic variability. Heterosis was negative for plant height, number of branches per plant, days to first harvest, fruit length, fruit width, and number of seed·per gram but positive for average fruit weight, number of fruit/plant, and fruit yield/plant. Average fruit weight ranged from 23.5 to 56.4 g; the heaviest fruit were from hybrids from the crosses ‘AC-824 × Sweet-72’, ‘CLN2237 × Sweet-72’, CLN2070 × Sweet-72’, and ‘CLN2070-09 × Punjab Chhuhara’; the smallest fruit were from hybrids from crosses ‘Selection 06-01 × PT-3’, ‘CLN2237 × PT-3’, ‘PT2007-09 × Punjab Chhuhara’, and ‘EC-519784 × Punjab Chhuhara’. The longest fruit were from hybrids from crosses ‘CLN2237 × Sweet-72’, ‘EC-519784 × Punjab Chhuhara’, ‘CLN2070 × Punjab Chhuhara’, and ‘EC-519784 × PT-3’; the shortest fruit were from hybrids from crosses ‘Selection 06-01 × Sweet-72’, ‘ARTH-3 × Punjab Chhuhara’, ‘Selection 06-01 × Punjab Chhuhara’, ‘AC-576 × Punjab Chhuhara’, and ‘PT-7 × PT-3’. The highest yield was from the hybrid from the cross ‘CLN2237 × Sweet-72’ followed by hybrids from the crosses ‘CLN2237 × Punjab Chhuhara’ and ‘PT2007-09 × Punjab Chhuhara’. Hybrids from crosses ‘CLN2237 × Sweet-72’, ‘CLN2237 × Punjab Chhuhara’, and ‘PT2007-09 × Punjab Chhuhara’ had 149.24, 36.43, and 28.92% higher heterosis compared to the better parent, respectively, for fruit yield/plant. Based on yield contributing characters and heterotic performance, hybrids from crosses ‘CLN2237 × Sweet-72’, ‘CLN2237 × Punjab Chhuhara’, and ‘PT2007-09 × Punjab Chhuhara’ can be used to develop improved commercial lines.