Gene action for fruit yield and its components in tomato (Lycopersicon esculentum Mill.)

Abstract

To provide an estimate of different non-allelic gene actions operating- in the inheritance of the quantitative traits and to investigate the genetics of fruit yield per plant and its contributing traits through generation mean analysis , the present study in tomato (Lycopersicon esculentum Mill.) was carried out. The study involved six generations, viz., Pl' P2' Fl' F2, BC1 and BC2 derived from each of the five crosses, namely, Alok x KM, BRH-1 x KM, BRH-2 x KM, TWC-3 x KM and Alok x TWC-3. These populations were grown in compact family block design with three replications during Rabi 2000-2001 in the experimental field of the Plant Breeding and Genetics Department of College of Agriculture, Central Agricultural University, Imphal, Manipur. The plant to plant and row to row distances were 40 cm and 60 cm, respectively. Data on ten randomly selected plants from each plot in the parents and Fl' 30 plants per plot in BC1 and BC2 and 40 plants per plot in F2 were recorded for nine characters viz., number of primary branches per plant, plant height, days to first flowering, days to first ripening, number of fruits per plant, fruit weight, equatorial diameter of the fruit, fruit yield per plant and locule number per fruit. The scaling tests A, B, C and D of Mather [1] were performed for all the characters under study to jUdge the adequacy of the additive - dominance model. The crosses, where the additive-dominance model was inadequate, were subjected to genetic analysis following Hayman [2], using the six-parameter model. In the absence of non-allelic interaction three-parameter model given by Jinks and Jones [3] was employed.