Germplasm genetic diversity & plant breeding
Aliakbar Babajanpour; SeyedHamidreza Hashemipetroudi; Mostafa Haghpanah
Abstract
Assessment of genetic diversity and individual relationships in rice (Oryza sativa) germplasm collections seems to be necessary for future rice breeding program. In order to understand genetic relationships of 30 rice genotypes, nine morphological traits, seven physicochemical properties and twelve RAPD ...
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Assessment of genetic diversity and individual relationships in rice (Oryza sativa) germplasm collections seems to be necessary for future rice breeding program. In order to understand genetic relationships of 30 rice genotypes, nine morphological traits, seven physicochemical properties and twelve RAPD primers were used for study of 30 rice genotypes. Among morphological traits, number of unfilled grain, number of tiller, number of filled grain and plant height had the highest CV value that indicated the high range of genetic diversity for studied genotypes. Pairwise correlation of morphological traits and physicochemical properties showed plant height had a strong positive correlation with panicle length (r = 0.721, P< 0.0001). Also, ratio of white rice to paddy rice and milling ratio had a negative correlation with plant height and 1000-grain weight, respectively. Cluster analysis of physicochemical properties and morphological traits grouped all genotypes into three main clusters. A total of 105 obtained RAPD bands, a number of 35 bands were polymorphs which range 7 to 19 bands per primer. OPB-14 and OPH-12 primers shown that lowest and the highest number of bands per primers, respectively. Cluster analysis of molecular data based on UPGMA algorithm and Jaccard's similarity coefficient grouped 30 rice genotypes into three clusters. The findings of this study might provide valuable information about local rice cultivar relationships in terms of their genetic distance, and can be useful in rice breeding program.
Molecular markers & plant breeding
Saumya Awasthi; Jai Prakash Lal
Abstract
Literatures have reported that a lot of drought related genes were cloned and individual gene showed positive effects under controlled stress experiments, but were not much effective in the field. Although, the progresses by conventional breeding approaches were achievable as some drought varieties have ...
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Literatures have reported that a lot of drought related genes were cloned and individual gene showed positive effects under controlled stress experiments, but were not much effective in the field. Although, the progresses by conventional breeding approaches were achievable as some drought varieties have been released to the farmers in the recent years but this is not adequate to cope up with the future demand of high yield for rice, as drought seems to spread to more regions and seasons. Therefore, marker assisted selection came into lime light for accelerating and giving pace to plant breeding.From the cross (Sarjoo- 52× Nagina- 22) × Sarjoo- 52, plants were selected on the basis of presence of gene MQTL1.1responsible for the drought tolerance. These lines have been subjected to further breeding and trial tests. Agronomic performances and physiological behavior of these lines are also under track. The results showed that the variety Sarjoo 52 could be efficiently converted to a drought tolerant variety in a backcross generation followed by selfing and selection, involving a time of two to three years. Polymorphic markers for foreground and background selection were identified for the high yielding variety to develop a wider range of drought tolerant variety to meet the needs of farmers in the drought-prone regions. This approach demonstrates the effective use of marker assisted selection for a major QTL in a molecular breeding program.