Nanjundan Joghee, Manjunatha Channappa, Radhamani Jalli, Thakur Ajay Kumar, Yadav Rashmi, Kumar Arun, Meena Mohan Lal, Tyagi Rishi Kumar, Yadava Devender Kumar, Singh Dhiraj
ICAR-Indian Agricultural Research Institute, Regional Station, Wellington, The Nilgiris, Tamil Nadu 643 231, India.
ICAR-National Bureau of Plant Genetic Resources, New Delhi 110 012, India.
Plant Pathol J. 2020 Apr 1;36(2):111-120. doi: 10.5423/PPJ.OA.07.2019.0205.
Powdery mildew of Indian mustard (), caused by , is emerging as major problem in India. All the Indian mustard cultivars presently grown in India are highly susceptible to powdery mildew and so far no resistance source has been reported. In this study, with an aim to identify resistant source, 1,020 Indian mustard accessions were evaluated against PMN isolate, at Wellington, The Nilgiris, Tamil Nadu, India under natural hot spot conditions. The study identified one accession (RDV 29) with complete resistance against PMN isolate for the first time, which was consistent in five independent evaluations. Genetic analysis of F, F and backcross populations obtained from the cross RSEJ 775 (highly susceptible) × RDV 29 (highly resistant) for two season revealed that the resistance is governed by two genes with semi-dominant and gene dosage effect. Further, a new disease rating system using six scales (0, 1, 2, 3, 4, and 5) has also been proposed in this study to score powdery mildew based on progress of fungal growth in different plant parts of the F population. The outcome of this study viz. newly identified powdery mildew-resistant Indian mustard accession (RDV 29), information on inheritance of resistance and the newly developed disease rating scale will provide the base for development of powdery mildew-resistant cultivars of Indian mustard.
由 引起的印度芥菜白粉病在印度正成为一个主要问题。目前在印度种植的所有印度芥菜品种对白粉病都高度敏感，迄今为止尚未报道有抗性来源。在本研究中，为了鉴定抗性来源，在印度泰米尔纳德邦尼尔吉里斯区的惠灵顿自然热点条件下，对1020份印度芥菜种质材料进行了针对PMN分离株的评估。该研究首次鉴定出一份对PMN分离株具有完全抗性的种质材料（RDV 29），在五次独立评估中结果一致。对从RSEJ 775（高感）×RDV 29（高抗）杂交获得的F1、F2和回交群体进行了两个季节的遗传分析，结果表明该抗性由两个具有半显性和基因剂量效应的基因控制。此外，本研究还提出了一种新的病害评级系统，使用六个等级（0、1、2、3、4和5），根据F2群体不同植株部位真菌生长的进展情况对白粉病进行评分。本研究的结果，即新鉴定出的抗白粉病印度芥菜种质材料（RDV 29）、抗性遗传信息以及新开发的病害评级量表，将为印度芥菜抗白粉病品种的培育提供基础。
