γ 射线辐照水稻突变体的遗传多样性、等位基因变异和标记性状关联。

Genetic diversity, allelic variation and marker trait associations in gamma irradiated mutants of rice ( L.).

机构信息

Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Killikulam, Tamil Nadu Agricultural University, India.

Department of Agriculture, School of Agriculture and Biosciences, Karunya Institute of Science and Technology, Coimbatore, India.

出版信息

Int J Radiat Biol. 2022;98(1):90-99. doi: 10.1080/09553002.2021.1987568. Epub 2021 Oct 27.

DOI:10.1080/09553002.2021.1987568

PMID:34587459

Abstract

PURPOSE

Rice is a prime staple crop for more than half of the world population. Improved White Ponni (IWP) is a premium quality grain rice variety that is fetching a good price and is increasingly popular among the consumers of Tamil Nadu. Tall plant stature of IWP makes them susceptible to lodging and medium duration are two undesirable traits in the variety increases yield losses in the field and also productivity. In this context, we aimed to generate a large mutant population of IWP irradiated with various doses of gamma irradiation to recover putative mutants for semi-dwarfism and earliness.

MATERIALS AND METHODS

Totally, 34 putative mutants 22 early, 11 semi-dwarf and early and 1 Narrow-leaf dwarf mutant) were phenotyped for nine morphological traits and genotyped using 34 microsatellite markers linked to a trait of interest of earliness and semi-dwarfism. Trait variability, allelic variations, genetic structure and marker-trait associations in gamma-irradiated putative mutants of Improved White Ponni (IWP) rice were investigated in this study.

RESULTS

The hierarchical clustering of morphological data produced five clusters with a dissimilarity coefficient of 1.39. A minimum dissimilarity coefficient of 0.23 was observed between the mutants IWPM9 and IWPM20 and a maximum dissimilarity coefficient of 2.55 was observed between IWPM1 and IWPM25. In cluster analysis with molecular marker data, five clusters with a similarity coefficient of 0.67 were observed. The mutant IWPM29 exhibited the most divergence from the wild type at the genotype level. The first principal component explained 50.99% of the total variability and the majority of the traits were contributed positively. The single-marker analysis revealed the strong association of SSR marker RM3912 with the traits plant height, panicle length and number of grains per panicle with an R value of 0.235, 0.235 and 0.250 respectively.

CONCLUSIONS

The study identified semi-dwarf and short-duration rice mutants of IWP that can be utilized as potential breeding stocks. The trait-linked SSR markers can improve selection cycles in advanced breeding programs.

摘要

目的

大米是世界上一半以上人口的主要主食。改良白蓬尼（IWP）是一种优质粮食品种，价格不菲，在泰米尔纳德邦的消费者中越来越受欢迎。IWP 的高大植物株使它们容易倒伏，中熟是该品种的两个不理想特征，这会导致田间产量损失增加，生产力降低。在这种情况下，我们旨在利用各种剂量的伽马射线辐照 IWP 产生大量突变体群体，以恢复半矮化和早熟的潜在突变体。

材料和方法

总共对 34 个假定突变体（22 个早熟、11 个半矮化和早熟以及 1 个窄叶矮化突变体）进行了表型分析，对 9 个形态性状进行了表型分析，并使用 34 个与早熟和半矮化相关性状相关的微卫星标记对其进行了基因型分析。本研究调查了伽马辐照改良白蓬尼（IWP）水稻假定突变体的性状变异性、等位基因变异、遗传结构和标记-性状关联。

结果

形态数据的层次聚类产生了五个聚类，相似系数为 1.39。突变体 IWPM9 和 IWPM20 之间的最小相似系数为 0.23，而 IWPM1 和 IWPM25 之间的最大相似系数为 2.55。在基于分子标记数据的聚类分析中，观察到五个聚类，相似系数为 0.67。在基因型水平上，突变体 IWPM29 与野生型的差异最大。第一主成分解释了总变异的 50.99%，大多数性状呈正贡献。单标记分析显示，SSR 标记 RM3912 与株高、穗长和每穗粒数三个性状的关联较强，R 值分别为 0.235、0.235 和 0.250。