Abd El-Aty Mohamed S, Katta Youssef S, El-Abd Abd El Moaty B, Mahmoud Samiha M, Ibrahim Omar M, Eweda Mohamed A, El-Saadony Mohamed T, AbuQamar Synan F, El-Tarabily Khaled A, El-Tahan Amira M
Department of Agronomy, Faculty of Agriculture, Kafr El Sheikh University, Kafr El-Sheikh, Egypt.
Rice Research and Training Center, Agricultural Research Center, Field Crops Research Institute, Kafr El-Sheikh, Egypt.
Front Plant Sci. 2022 Jul 8;13:866742. doi: 10.3389/fpls.2022.866742. eCollection 2022.
Drought is considered a major threat to rice production. This study aimed to determine the effects of drought stress on the estimates of heterosis and the combining ability of rice genotypes for the number of days to 50% heading, plant height, number of panicles per plant, panicle length, number of filled grains per panicle, and grain yield per plant. Field experiments were conducted at the Rice Research and Training Center, Kafr El Sheikh, Egypt, during the rice-growing season in 2018 and 2019. Eight rice genotypes (Giza178, Giza179, Sakha106, Sakha107, Sakha108, WAB1573, NERICA4, and IET1444) were crossed in a half-diallel cross in the rice-growing season in 2018, which yielded a wide range of variability in numerous agronomic traits and drought tolerance measurements. In 2019, these parents and their 28 F crosses were produced by employing a three-replication randomized complete block design under normal and water stress conditions. The results showed remarkable differences across the studied genotypes under normal and water stress conditions. Under both conditions, Sakha107 was the best general combiner for earliness and short stature. Giza179 and Sakha108 were the best general combiners for grain yield per plant and one or more of its characteristics. Furthermore, in both normal and water stress conditions, Giza179 exhibited the highest general combining ability effects for all attributes that were evaluated. Under normal and water stress conditions, the Giza179 × Sakha107 cross demonstrated substantial and desirable specific combining ability effects on all the examined traits, which suggested that it could be considered for use in rice hybrid breeding programs. Therefore, we recommend that these vital indirect selection criteria to be considered for improving rice grain yield under drought conditions.
干旱被认为是水稻生产的主要威胁。本研究旨在确定干旱胁迫对水稻基因型抽穗至50%所需天数、株高、单株穗数、穗长、每穗实粒数和单株产量的杂种优势估计值及配合力的影响。2018年和2019年水稻生长季期间，在埃及卡夫尔谢赫的水稻研究与培训中心进行了田间试验。2018年水稻生长季，8个水稻基因型（吉萨178、吉萨179、萨哈106、萨哈107、萨哈108、WAB1573、NERICA4和IET1444）进行了半双列杂交，在众多农艺性状和耐旱性测量方面产生了广泛的变异性。2019年，这些亲本及其28个F代杂交种采用三次重复随机完全区组设计，在正常和水分胁迫条件下种植。结果表明，在正常和水分胁迫条件下，所研究的基因型之间存在显著差异。在两种条件下，萨哈107都是早熟和矮秆的最佳一般配合者。吉萨179和萨哈108是单株产量及其一个或多个特征的最佳一般配合者。此外，在正常和水分胁迫条件下，吉萨179对所有评估的性状均表现出最高的一般配合力效应。在正常和水分胁迫条件下，吉萨179×萨哈107杂交组合对所有检测性状均表现出显著且理想的特殊配合力效应，这表明它可考虑用于水稻杂交育种计划。因此，我们建议在干旱条件下改良水稻籽粒产量时应考虑这些重要的间接选择标准。
