Department of Genetics and Plant Breeding, TNAU, Coimbatore, India.
Department of Genetics and Plant Breeding, AC & RI, TNAU, Kudumiyanmalai, India.
Int J Radiat Biol. 2023;99(8):1267-1284. doi: 10.1080/09553002.2023.2173820. Epub 2023 Feb 6.
During post-rainy and rice fallow cropping seasons, popular blackgram varieties are severely affected by powdery mildew leading to severe yield loss. The lack of natural genetic variability for powdery mildew resistance in blackgram germplasm warrants mutation breeding. Hence, in this study, blackgram cultivar CO6 was mutagenized with gamma ray and ethyl methanesulphonate (EMS) to create variability for powdery mildew resistance.
Seeds of blackgram CO6 were irradiated with three doses of gamma ray (200 Gy, 300 Gy and 400 Gy) followed by two doses of ethyl methanesulphonate (EMS; 20 and 30 mM) to achieve six combination treatments. Selected resistant mutants of M generation were characterized for agronomic, histological, enzyme and biochemical traits along with powdery mildew resistant LBG 17 and susceptible CO6 checks. Molecular variability was studied using 72 simple sequence repeat (SSR) markers.
In the M generation, 60 powdery mildew resistant mutants were identified and a total of 25 high yielding mutants were evaluated further to confirm powdery mildew resistance and yield. Nine resistant mutants (PM 13, PM 20, PM 21, PM 42, PM 53, PM 54, PM 56, PM 57 and PM 60) and the resistant check (LBG17) showed significantly higher values for leaf density, trichome density, SOD, CAT, POX, PPO, total phenols, phytic acid and silica content. SSR markers ., CEDG154, CEDG290, CEDG139, CEDG259, CEDG191, CEDG024, CEDG 282, CEDG 166, CEDG 232 and CEDG 088 were found polymorphic between resistant mutants and the parent CO6.
The study has demonstrated that sufficient variability was induced in the blackgram for powdery mildew resistance. The elevated levels of SOD, CAT, POX, PPO, total phenols, phytic acid, and silica content observed in selected mutants may be attributed to powdery mildew resistance. The superior mutants identified in this study may be used as donors for the development of powdery mildew resistant lines or released as a new variety.
在雨后和水稻休耕季节，受白粉病影响，流行的黑豆品种严重减产。黑豆种质资源中缺乏对白粉病的天然遗传变异，因此需要进行诱变育种。因此，本研究用γ射线和甲基磺酸乙酯（EMS）对黑豆品种 CO6 进行诱变，以创造对白粉病的抗性变异。
用三种剂量的γ射线（200Gy、300Gy 和 400Gy）和两种剂量的甲基磺酸乙酯（EMS；20mM 和 30mM）对黑豆 CO6 种子进行辐照，共得到 6 种组合处理。对 M 代中选择的抗白粉病突变体进行农艺、组织学、酶和生化特性以及抗白粉病 LBG17 和感病 CO6 对照的鉴定。利用 72 个简单重复序列（SSR）标记进行分子变异研究。
在 M 代中，共鉴定出 60 个抗白粉病突变体，进一步评价了 25 个高产突变体，以确认抗白粉病和产量。9 个抗白粉病突变体（PM13、PM20、PM21、PM42、PM53、PM54、PM56、PM57 和 PM60）和抗病对照（LBG17）的叶片密度、毛密度、SOD、CAT、POX、PPO、总酚、植酸和硅含量均显著较高。SSR 标记 CEDG154、CEDG290、CEDG139、CEDG259、CEDG191、CEDG024、CEDG282、CEDG166、CEDG232 和 CEDG088 在抗白粉病突变体与亲本 CO6 之间表现出多态性。
本研究表明，在黑豆中诱导了足够的白粉病抗性变异。在选择的突变体中观察到 SOD、CAT、POX、PPO、总酚、植酸和硅含量的升高可能与白粉病抗性有关。本研究中鉴定出的优良突变体可作为抗白粉病系的供体，或作为一个新品种释放。
