Title: Preliminary evaluation of yield of imported hybrid rice lines under different conditions of Iran
Author: Aliakbar Ebadi
Abstract: Rice is the main food of Iranians and people in many countries of the world. Due to the fact that the population is increasing and the climatic restrictions for the cultivation of crops, including rice, are increasing, it is necessary to increase rice production and nutritional value. Utilization of heterosis in hybrid cultivars as a solution to further increase the yield and quality of rice grains. Therefore, the aim of this study was the preliminary comparison of the yield of 22 genotypes including 21 hybrid rice lines with a control cultivar (improved cultivar Gohar) in a randomized complete block design with three replications in the research farm of the Rice Research Institute of Iran. The results of the analysis of variance showed that the mean squares of genotypes for all traits were significant at the level of one percent probability, which indicates that there is a significant genetic difference between genotypes in terms of evaluated traits. Examination of phenotypic correlation coefficients between traits showed that the highest positive phenotypic correlation was between grain length and grain shape (r = 0.72) and the highest negative phenotypic correlation was between the head rice percent and broken rice percent (r = -0.93). Genotypes were classified based on the studied traits by cluster analysis and genotypes were divided into three groups based on the studied traits with similar in-group and different out-group characteristics. According to the set of examined traits, especially yield and cooking quality, four cultivars (A-4, CH-3, CH-7 and CH-9) were superior to the rest of the cultivars and were chosen as selected cultivars for further studies.
Keywords: Rice, Hybrid, Heterosis, Cluster analysis