Division of Genetics, Indian Agricultural Research Institute, New Delhi, India
**Present address: Department of Genetics, Haryana Agricultural University, Hissar.
*Part of thesis submitted by V. P. SINGH for the Ph. D. degree of Indian Agricultural Research Institute, Delhi-12.
Different filial generations of the two crosses, viz., S. 15 × S. 110 and S. 15 × PSWF, were subjected to an analysis of components of variation using second degree statistics following the methodology developed by Mather (1948). The same material was used for the estimation of gene effects through analysis of generation means following the procedure proposed by Hayman (1958) and Jinks and Jones (1958).
Mather's analysis revealed apparent overdominance both in respect of fruit yield as well as components of such yield, the additive portion being insignificant for most of the characters. The parameter H/D0.5 was larger than unity, suggesting overdominance. Analysis of generation means using the 3-parameter model as well as 5-parameter model indicated good fit, particularly much closer with the 5-parameter model. The non-epistatic model again showed the preponderance of h components and considerable overdominance but the epistatic model showed that the h component was non-significant. The apparent overdominance is, perhaps, due to epistasis and linkage effects.
