Department of Genetics, University of California, Berkeley
*Present address: Division of Genetics, Indian Agricultural Research Institute, Delhi-12.
1Part of thesis submitted in partial satisfaction of the requirements of the Ph.D. degree of the University of California, Berkeley.
A genetic analysis of locule number by means of diallel crosses was performed using eleven inbred lines of the tomato. The validity of certain assumptions which are basic to the analysis was investigated. Interaction of genotype with environment was detected on the arithmetic scale as well as on the logarithmic scale. However, a logarithmic transformation of the data was shown to be useful in minimising this interaction. On the logarithmic scale epistatic interactions were not detected.
Dominance estimates indicated, that on the average there was a partial dominance of low locule number over high locule number. There was an excess of recessive genes in the parental lines and the distribution of positive and negative alleles for dominance was highly asymmetrical.
Analysis of g.c.a. and s.c.a. effects showed predominant role of non-additive genetic effects. The parents differed significantly in their g.c.a. effects so also the F1’s in s.c.a. effects. However, all F1’s exhibited negative values of s.c.a. effects. Possibilities of selecting fruits for high locule number and large size are discussed.
