Year : 2005, Volume : 32, Issue : 1 and 2
Print ISSN : 0970-8235.
Genetic divergence and its relationship with heterosis in potato*
Luthra S.K.1, Gopal J.2, Sharma P.C.3,**
1Central Potato Research Institute Campus, Modipuram, Meerut 250110, Uttar Pradesh, India
2Central Potato Research Institute, Shimla 171 001, Himachal Pradesh, India
3Chaudhary Charan Singh University, Meerut 250 004, Uttar Pradesh, India
**Present address: Guru Gobind Singh Indraprastha University, New Delhi 110 006, India
*CPRI Publication No. 1760
The success of potato breeding programmes depends mainly on the identification of promising parental lines for making desired crosses and selection of superior genotypes from the progenies. Distantly related lines are assumed to be more complementary and produce superior heterotic progenies (6, 10, 12). Heterosis as a function of genetic divergence is known to have only a moderate effectiveness in predicting tuber yield of potato progenies and for this too parents need to be evaluated under conditions where progenies from these parents are to be subjected to selection (4). In the present investigation, genetic divergence among 29 potato genotypes (parents) and performance of 120 progenies generated from these parents were evaluated under similar conditions to identify diverse parents and verify relationship between genetic divergence and performance (progeny mean and heterosis) of progenies for tuber yield.
Results showed that the parental lines though morphologically diverse had narrow genetic base and could be grouped into four clusters. Observed morphological diversity was not related to geographical as well as taxonomic diversity. Genetic divergence (D values) had a positive relationship with heterosis for tuber yield in the 120 progenies derived from 24 x 5 (line x tester) matings of the parents. Selection of parents based on genetic divergence followed by progeny test is suggested for effective exploitation of heterosis in potato breeding programmes.