Gill Jujhar Singh, Chahal Prabhjot Singh, Kumar Naveen, Yadav Bharat, Brar Gurcharn Singh
Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC, Canada.
Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada.
Methods Mol Biol. 2025;2898:231-243. doi: 10.1007/978-1-0716-4378-5_14.
The three fungal diseases-leaf rust, stem rust, and stripe rust-are considerable challenges to wheat production, causing up to 20%, 50%, and 70% yield losses, respectively, in North America and across the world. Control strategies include regular introduction of resistant varieties as well as fungicidal applications. Stripe rust, caused by Puccinia striiformis f. sp. tritici, is best controlled by utilizing genetic resistance and regularly introducing resistant varieties to combat the rapid breakdown of host resistance by the pathogen. Genetic resistance to stripe rust can be characterized as adult plant resistance (APR) or all-stage resistance (ASR), the former being largely preferred due to the durable mechanisms governing its resistance. Breeding programs utilize large germplasm collections to screen for resistance. Field phenotyping is a critical component for breeding programs, helping in selection of resistant breeding lines to artificial epidemics of relevant pathotypes. This chapter summarizes the methods and protocols for the field phenotyping of stripe rust at the adult-plant stage, including the steps for inoculation, phenotyping, and an overview of the favorable environmental conditions for optimal results. We also summarize methods for phenotyping leaf tip necrosis (LTN), a morphological trait expressed via slow-rusting APR genes. We demonstrated the process of screening over 30,000 lines of wheat-including the organization of entries using, ideal stage for inoculum application to screen for APR, and the ideal stage for phenotyping 10-18 days postinoculation (DPI). In conclusion, field phenotyping is critical in the assessment of stripe rust resistance and development of resistant varieties and is a major component in combatting global stripe rust epidemics in a sustainable and environmentally considerate way.
叶锈病、秆锈病和条锈病这三种真菌病害对小麦生产构成了巨大挑战，在北美和全球分别造成高达20%、50%和70%的产量损失。防治策略包括定期引入抗性品种以及施用杀菌剂。由条形柄锈菌小麦专化型（Puccinia striiformis f. sp. tritici）引起的条锈病，最好通过利用遗传抗性并定期引入抗性品种来控制，以对抗病原体导致的宿主抗性快速丧失。对条锈病的遗传抗性可分为成株抗性（APR）或全生育期抗性（ASR），由于其抗性的持久机制，前者更受青睐。育种计划利用大量种质资源库来筛选抗性。田间表型分析是育种计划的关键组成部分，有助于选择对相关致病型人工流行具有抗性的育种系。本章总结了成株期条锈病田间表型分析的方法和方案，包括接种、表型分析步骤以及对获得最佳结果有利环境条件的概述。我们还总结了叶尖坏死（LTN）表型分析的方法，叶尖坏死是一种通过慢锈性成株抗性基因表达的形态性状。我们展示了对30000多个小麦品系进行筛选的过程，包括条目组织、接种接种物以筛选成株抗性的理想阶段以及接种后10 - 18天（DPI）进行表型分析的理想阶段。总之，田间表型分析对于评估条锈病抗性和培育抗性品种至关重要，并且是以可持续和环境友好方式应对全球条锈病流行的主要组成部分。
