Abbas Hira, Nahid Nazia, Rehman Muhammad Shah Nawaz Ul, Shaheen Tayyaba, Liaquat Sadia
Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad 38000, Pakistan.
Centre of Agricultural Biochemistry and Biotechnology, University of Agriculture Faisalabad, Faisalabad 38000, Pakistan.
Plant Pathol J. 2024 Feb;40(1):59-72. doi: 10.5423/PPJ.OA.03.2023.0048. Epub 2024 Feb 1.
A comprehensive survey of mungbean-growing areas was conducted to observe leaf spot disease caused by Alternaria alternata. Alternaria leaf spot symptoms were observed on the leaves. Diversity of 50 genotypes of mungbean was assessed against A. alternata and data on pathological traits was subjected to cluster analysis. The results showed that genotypes of mungbean were grouped into four clusters based on resistance parameters under the influence of disease. The principal component biplot demonstrated that all the disease-related parameters (% disease incidence, % disease intensity, lesion area, and % of infection) were strongly correlated with each other. Alt a 1 gene that is precisely found in Alternaria species and is responsible for virulence and pathogenicity. Alt a 1 gene was amplified using gene specific primers. The isolated pathogen produced similar symptoms when inoculated on mungbean and tobacco. The sequence analysis of the internal transcribed spacer (ITS) region, a 600 bp fragment amplified using specific primers, ITS1 and ITS2 showed 100% identity with A. alternata. Potato virus X (PVX) -based silencing vector expressing Alt a 1 gene was constructed to control this pathogen through RNA interference in tobacco. Out of 50 inoculated plants, 9 showed delayed onset of disease. Furthermore, to confirm our findings at molecular level semi-quantitative reverse transcriptase polymerase chain reaction was used. Both phenotypic and molecular investigation indicated that RNAi induced through the VIGS vector was efficacious in resisting the pathogen in the model host, Tobacco (Nicotiana tabacum). To the best of our knowledge, this study has been reported for the first time.
对绿豆种植区进行了全面调查，以观察由链格孢引起的叶斑病。在叶片上观察到链格孢叶斑症状。评估了50个绿豆基因型对链格孢的抗性，并对病理性状数据进行了聚类分析。结果表明，在病害影响下，绿豆基因型根据抗性参数被分为四个聚类。主成分双标图表明，所有与病害相关的参数（发病率、病情严重度、病斑面积和感染率）彼此之间都有很强的相关性。在链格孢属物种中准确发现的Alt a 1基因，负责毒力和致病性。使用基因特异性引物扩增Alt a 1基因。分离出的病原菌接种到绿豆和烟草上时产生了相似的症状。使用特异性引物ITS1和ITS2扩增的600 bp片段——内部转录间隔区（ITS）区域的序列分析显示，与链格孢的序列一致性为100%。构建了基于马铃薯X病毒（PVX）的表达Alt a 1基因的沉默载体，通过烟草中的RNA干扰来控制这种病原菌。在50株接种的植株中，有9株病害发病延迟。此外，为了在分子水平上证实我们的发现，使用了半定量逆转录聚合酶链反应。表型和分子研究均表明，通过病毒诱导基因沉默（VIGS）载体诱导的RNA干扰在模式宿主烟草（Nicotiana tabacum）中对病原菌具有抗性。据我们所知，本研究首次被报道。
