Afrin Wazifa, Nafis Mahmudul Hassan, Hossain Muhammed Ali, Islam Mirza Mofazzal, Hossain Md Amir
Department of Genetics & Plant Breeding, Bangladesh Agricultural University, 2202 Mymensingh, Bangladesh; Plant Breeding Division, Bangladesh Rice Research Institute, Gazipur, Bangladesh.
Department of Genetics & Plant Breeding, Bangladesh Agricultural University, 2202 Mymensingh, Bangladesh.
C R Biol. 2018 Feb;341(2):85-96. doi: 10.1016/j.crvi.2018.01.001. Epub 2018 Feb 3.
The study aims at identifying some submergence-tolerant rice genotypes through morphological and molecular characterization and their genetic variability analysis. Ten rice genotypes including two submergence-tolerant checks, two susceptible varieties and six advanced lines were evaluated for submergence tolerance in the laboratory and in the field during January-December 2015. The experiment was conducted in the field following randomized complete block design in a two-factor arrangement using five replications. Ten characters, viz. days to flowering, plant height, tiller number plant, effective tiller plant, and yield plant etc. were studied for four treatments. A significant genotype×environment interaction was observed for all traits studied in this experiment. The yield was reduced for all genotypes at a different level of submergence stress compared to control. Binadhan-11, Binadhan-12, RC 249 and RC 251 showed tolerance, whereas RC 192, RC 193 and RC 225 showed moderate tolerance in submerged condition. The phenotypic coefficient of variance (PCV) was higher than the genotypic coefficient of variance (GCV) in all the studies traits. High heritability (75-97%) was found for all traits. High heritability along with high genetic advance was found for days to flowering (45.55) and plant height (40.05). Molecular characterization of the used genotypes was done with three SSR markers viz. RM 24, and submergence specific SC3 and SUB1. SC3 was found reliable for detection of submergence tolerant genotypes due to the highest gene diversity (0.840) compared to others. The banding pattern of the submergence specific markers SC3 and SUB1 identified in Binadhan-11, Binadhan-12, RC 192, RC 193, RC 225, RC 227, RC 249, and RC 251, which possess the SUB1 gene. Finally, clustering also separates the tolerant genotypes from the susceptible by dividing them into different clusters. The identified genotypes might be useful for the breeding programme for the development of submergence tolerant as well as resistant rice variety in Bangladesh.
本研究旨在通过形态学和分子特征鉴定一些耐淹水稻基因型，并对其遗传变异性进行分析。2015年1月至12月期间，在实验室和田间对包括两个耐淹对照品种、两个感病品种和六个新品系在内的十个水稻基因型进行了耐淹性评估。试验在田间采用随机完全区组设计，二因素排列，重复五次。对四个处理研究了十个性状，即开花天数、株高、单株分蘖数、单株有效分蘖数和单株产量等。本试验研究的所有性状均观察到显著的基因型×环境互作。与对照相比，在不同淹水胁迫水平下，所有基因型的产量均有所降低。Binadhan - 11、Binadhan - 12、RC 249和RC 251表现出耐受性，而RC 192、RC 193和RC 225在淹水条件下表现出中等耐受性。在所有研究性状中，表型变异系数（PCV）高于基因型变异系数（GCV）。所有性状均具有较高的遗传力（75% - 97%）。开花天数（45.55）和株高（40.05）具有较高的遗传力和较高的遗传进展。使用三个SSR标记，即RM 24以及淹水特异性标记SC3和SUB1对所用基因型进行了分子特征分析。由于与其他标记相比，SC3具有最高的基因多样性（0.840），因此发现其对检测耐淹基因型可靠。在Binadhan - 11、Binadhan - 12、RC 192、RC 193、RC 225、RC 227、RC 249和RC 251中鉴定出的淹水特异性标记SC3和SUB1的条带模式，这些基因型含有SUB1基因。最后，聚类分析也通过将耐淹基因型和感病基因型分为不同的簇将它们分开。鉴定出的基因型可能对孟加拉国耐淹和抗病水稻品种的育种计划有用。
