Journal of Applied Horticulture. 2004: 6(2): 45-47

Genetical studies on yield and its components in tomato

Viveka Katoch; Vidyasagar

Department of Vegetable Science, H.P. Agricultural University, Palampur - 176 062, India.

An experiment was conducted to understand the nature of gene effects for yield and its component characters in tomato. Six generations, (P1, P2, F1, F2, B1 and B2) of Hawaii 7998 x BT-18, Hawaii 7998 x EC 191536 and BT-18 x EC 191536, derived after crossing the bacterial wilt resistant parents, were studied following 3-parameter model of Cavalli (1952) and 6-parameter model of Jink and Jones (1958). Duplicate epistasis with relatively higher magnitude of [l] interaction (+) was observed for marketable yield per plant and number of marketable fruits per plant in Hawaii 7998 x BT-18 and BT-18 x EC 191536, thus suggesting a need for exploitation of hybrid vigour or intermating followed by selection in later generations, in these crosses. Whereas, the presence of additive effects [d and i] in Hawaii 7998 x EC 191536 indicated the importance of simple pedigree selection. For the traits related to earliness (days to 50% flowering and days to first harvest), pedigree selection in BT-18 x EC 191536 and pedigree selection including hybrids in Hawaii 7998 x EC 191536 could be utilized for the presence of both additive and non-additive gene effects, respectively.