Pandey Sarita K, Dasgupta Tapash, Rathore Abhishek, Vemula Anilkumar
International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India.
Department of Genetics and Plant Breeding, Institute of Agricultural Science, Calcutta University, Kolkata, India.
Biochem Genet. 2018 Jun;56(3):188-209. doi: 10.1007/s10528-017-9837-2. Epub 2018 Jan 10.
The genetic distance analysis for selection of suitable parents has been established and effectively used in many crops; however, there is dearth of conclusive report of relationship of genetic distance analysis with heterosis in sesame. In the present study, an attempt was made to estimate the associations of genetic distances using SSR (GDSSR), seed-storage protein profiling (GDSDS) and agro-morphological traits (GDMOR) with hybrid performance. Seven parents were selected from 60 exotic and Indian genotypes based on genetic distance from clustering pattern based on SSR, seed-storage protein, morphological traits and per se performance. For combining ability analysis, 7 parents and 21 crosses generated from 7 × 7 half diallel evaluated at two environments in a replicated field trial during pre-kharif season of 2013. Compared with the average parents yield (12.57 g plant), eight hybrids had a significant (P < 0.01) yield advantage across environments, with averages of 26.94 and 29.99% for better-parent heterosis (BPH) and mid-parent heterosis (MPH), respectively, across environments. Highly significant positive correlation was observed between specific combining ability (SCA) and per se performance (0.97), while positive non-significant correlation of BPH with GDSSR (0.048), and non-significant negative correlations with GDMOR (- 0.01) and GDSDS (- 0.256) were observed. The linear regressions of SCA on MPH, BPH and per se performance of Fs were significant with R value of 0.88, 0.84 and 0.95 respectively. The present findings revealed a weak association of GDSSR with F's performance; however, SCA has appeared as an important factor in the determination of heterosis and per se performance of the hybrids. The present findings also indicated that parental divergence in the intermediate group would likely produce high heterotic crosses in sesame.
用于选择合适亲本的遗传距离分析已在许多作物中建立并得到有效应用；然而，关于芝麻遗传距离分析与杂种优势关系的确凿报告却很少。在本研究中，尝试利用SSR（GDSSR）、种子贮藏蛋白谱分析（GDSDS）和农艺形态性状（GDMOR）来估计遗传距离与杂交种表现之间的关联。基于SSR、种子贮藏蛋白、形态性状和自身表现的聚类模式所确定的遗传距离，从60个外来和印度基因型中选择了7个亲本。为了进行配合力分析，在2013年雨季前季节的重复田间试验中，于两个环境下对7个亲本和由7×7半双列杂交产生的21个杂交组合进行了评估。与亲本平均产量（12.57 g/株）相比，有8个杂交种在各环境下具有显著（P<0.01）的产量优势，全环境下较好亲本杂种优势（BPH）和中亲杂种优势（MPH）的平均值分别为26.94%和29.99%。观察到特殊配合力（SCA）与自身表现之间存在极显著正相关（0.97），而BPH与GDSSR之间存在正的不显著相关（0.048），与GDMOR（-0.01）和GDSDS（-0.256）之间存在不显著的负相关。SCA对F1的MPH、BPH和自身表现的线性回归显著，R值分别为0.88、0.84和0.95。本研究结果表明GDSSR与F1表现之间的关联较弱；然而，SCA已成为决定杂种优势和杂交种自身表现的一个重要因素。本研究结果还表明，中间组的亲本差异可能会在芝麻中产生高杂种优势的杂交组合。
