Genetic Variability and Divergence of Maize Landraces in Nepal
Maize landraces, which are well adapted to the local socioeconomic production environments, are important sources of genetic variability. They have not been sufficiently exploited and utilized in cultivar development. The objectives of this study were to estimate genetic variability and measure the genetic divergence of these valuable landraces for use in breeding programs. Twenty-seven landraces with high yield potential, along with four standard checks, were evaluated under two production environments during the 2000～2001 summer and winter seasons. The experiment was laid out in a randomized complete block design with two replications. Genotypic and phenotypic coefficients of variation, broad-sense heritability, and genetic advance were estimated. Similarly, D2 values, grouping of clusters, and intercluster distances were measured. Grain yield, ear height, number of kernels per ear, plant height, and 1000-grain weight showed maximum genetic variability. Shelling percentage, ear circumference, number of rows per ear, and number of ears per plant revealed mini-mum variability. Number of kernels per row, days to tasseling, and ear and plant height showed maximum heritability. Five clusters were made on the basis of D2 values. Number of kernels per ear, shelling percentage, days of maturity, ear length, and 1000-grain weight contributed to maximum genetic divergence, whereas days to silking and number of ears per plant contributed nothing. The maximum and minimum intercluster distances were observed in clusters Ⅳ, Ⅲ, and Ⅱ. The landraces from these clusters are genetically more divergent and can be utilized in hybrid development as well as population improvement programs.
Landraces Variability Heritability Genetic advance Divergence Clusters
Dil Bahadur Gurung Bhanu Bhakta Pokhrel Keshab Babu Koirala Krishna Adhikari
Nepal Agricultural Research Council, Agricultural Research Station, Dailekh, Nepal Nepal Agricultural Research Council, Agricultural Research Station, Lumle, Nepal Nepal Agricultural Research Council, National Maize Research Program, Rampur, Nepal
国际会议
第九届亚洲玉米大会(the Ninth Asian Regional Maize Workshop)
北京
英文
25-30
2005-09-05（万方平台首次上网日期，不代表论文的发表时间）