Songsomboon Kittikun, Crawford Ryan, Crawford Jamie, Hansen Julie, Cummings Jaime, Mattson Neil, Bergstrom Gary C, Viands Donald R
Section of Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.
Syngenta, Trumansburg, NY 14886, USA.
Plants (Basel). 2022 May 20;11(10):1362. doi: 10.3390/plants11101362.
Switchgrass ( L.), a northern native perennial grass, suffers from yield reduction from Bipolaris leaf spot caused by (Breda de Haan) Shoemaker. This study aimed to determine the resistant populations via multiple phenotyping approaches and identify potential resistance genes from genome-wide association studies (GWAS) in the switchgrass northern association panel. The disease resistance was evaluated from both natural (field evaluations in Ithaca, New York and Phillipsburg, Philadelphia) and artificial inoculations (detached leaf and leaf disk assays). The most resistant populations based on a combination of three phenotyping approaches-detached leaf, leaf disk, and mean from two locations-were 'SW788', 'SW806', 'SW802', 'SW793', 'SW781', 'SW797', 'SW798', 'SW803', 'SW795', 'SW805'. The GWAS from the association panel showed 27 significant SNPs on 12 chromosomes: 1K, 2K, 2N, 3K, 3N, 4N, 5K, 5N, 6N, 7K, 7N, and 9N. These markers accumulatively explained the phenotypic variance of the resistance ranging from 3.28 to 26.52%. Within linkage disequilibrium of 20 kb, these SNP markers linked with the potential resistance genes included the genes encoding for NBS-LRR, PPR, cell-wall related proteins, homeostatic proteins, anti-apoptotic proteins, and ABC transporter.
柳枝稷（Panicum virgatum L.）是一种原产于北方的多年生草本植物，受玉米大斑病菌（Setosphaeria turcica (Luttrell) Leonard & Suggs）引起的玉米大斑病影响而减产。本研究旨在通过多种表型分析方法确定抗性群体，并从柳枝稷北方关联群体的全基因组关联研究（GWAS）中鉴定潜在的抗性基因。通过自然接种（纽约伊萨卡和宾夕法尼亚州菲利普斯堡的田间评估）和人工接种（离体叶片和叶盘试验）对抗病性进行评估。基于离体叶片、叶盘和两个地点的平均值这三种表型分析方法组合得出的最抗病群体为'SW788'、'SW806'、'SW802'、'SW793'、'SW781'、'SW797'、'SW798'、'SW803'、'SW795'、'SW805'。关联群体的GWAS显示在12条染色体上有27个显著的单核苷酸多态性（SNP）：1K、2K、2N、3K、3N、4N、5K、5N、6N、7K、7N和9N。这些标记累计解释了抗性表型变异的3.28%至26.52%。在20 kb的连锁不平衡范围内，这些与潜在抗性基因连锁的SNP标记包括编码NBS-LRR、PPR、细胞壁相关蛋白、稳态蛋白、抗凋亡蛋白和ABC转运蛋白的基因。
