Khalifa Walaa, Khalil Hala Badr, Thabet Marian
Department of Plant Pathology, Faculty of Agriculture, Ain Shams University, Cairo 11241, Egypt.
Department of Biological Sciences, College of Science, King Faisal University, Al-Ahsa 31982, Saudi Arabia.
Plants (Basel). 2024 Nov 28;13(23):3344. doi: 10.3390/plants13233344.
Quinoa ( Willd.) is a new, promising non-conventional useful crop; however, its susceptibility to downy mildew, caused by , is a key obstacle limiting its productivity in Egypt. Identifying and utilizing resistant quinoa cultivars appear to be reliable and cost-efficient strategies for controlling downy mildew, particularly in resource-limited farmers' fields. This study aimed to evaluate the differential resistance of the Peruvian "" and Bolivian "" quinoa cultivars to infection under laboratory conditions to provide precise insight into their basic defense mechanism(s). Inoculated "" plants displayed complete resistance against , with no visible symptoms (incompatible reaction), while those of "" plants revealed high susceptibility (compatible reaction), with typical downy mildew lesions on their leaf surfaces. Disease incidence reached about 66% in the inoculated "" plants, with most inoculated leaves having lesions of grades 4 and 5 covering up to 90% of their leaf surfaces. Susceptibility indices reached up to 66% in the inoculated "" plants. Resistance to observed in the "" plants may have been largely attributed to elevated endogenous HO levels, increased peroxidase (POX) activity and abundance, enhanced phenylalanine ammonia-lyase (PAL) activity and expression, as well as the upregulation of the pathogen-related protein 10 gene (). The results of this study indicate that the quinoa cultivar "" not only is a promising candidate for sustainable control of quinoa downy mildew but also, through a deep understanding of its molecular resistance mechanisms, would provide a possible route to enhance downy mildew resistance in other genotypes.
藜麦（藜麦属）是一种新型且有前景的非传统有益作物；然而，它对由[病原菌名称缺失]引起的霜霉病敏感，这是限制其在埃及产量的关键障碍。鉴定和利用抗性藜麦品种似乎是控制霜霉病可靠且经济高效的策略，特别是在资源有限的农田中。本研究旨在评估秘鲁“[品种名称缺失]”和玻利维亚“[品种名称缺失]”藜麦品种在实验室条件下对[病原菌名称缺失]感染的差异抗性，以深入了解其基本防御机制。接种“[品种名称缺失]”的植株对[病原菌名称缺失]表现出完全抗性，无可见症状（不相容反应），而“[品种名称缺失]”植株表现出高度敏感性（相容反应），叶片表面有典型的霜霉病病斑。接种“[品种名称缺失]”的植株发病率约为66%，大多数接种叶片有4级和5级病斑，覆盖叶片表面达90%。接种“[品种名称缺失]”的植株易感性指数高达66%。在“[品种名称缺失]”植株中观察到的对[病原菌名称缺失]的抗性可能很大程度上归因于内源性HO水平升高、过氧化物酶（POX）活性和丰度增加、苯丙氨酸解氨酶（PAL）活性和表达增强以及病程相关蛋白10基因（[基因名称缺失]）上调。本研究结果表明，藜麦品种“[品种名称缺失]”不仅是可持续控制藜麦霜霉病的有前景候选品种，而且通过深入了解其分子抗性机制，将为增强其他基因型对霜霉病的抗性提供可能途径。
