DataSheet_1_Genetic diversity, population structure and anthracnose resistance response in a novel sweet sorghum diversity panel.docx

Sweet sorghum is an attractive feedstock for the production of renewable chemicals and fuels due to the readily available fermentable sugars that can be extracted from the juice, and the additional stream of fermentable sugars that can be obtained from the cell wall polysaccharides in the bagasse. An important selection criterion for new sweet sorghum germplasm is resistance to anthracnose, a disease caused by the fungal pathogen Colletotrichum sublineolum. The identification of novel anthracnose-resistance sources present in sweet sorghum germplasm offers a fast track towards the development of new resistant sweet sorghum germplasm. We established a sweet sorghum diversity panel (SWDP) of 272 accessions from the USDA-ARS National Plant Germplasm (NPGS) collection that includes landraces from 22 countries and advanced breeding material, and that represents ~15% of the NPGS sweet sorghum collection. Genomic characterization of the SWDP identified 171,954 single nucleotide polymorphisms (SNPs) with an average of one SNP per 4,071 kb. Population structure analysis revealed that the SWDP could be stratified into four populations and one admixed group, and that this population structure could be aligned to sorghum’s racial classification. Results from a two-year replicated trial of the SWDP for anthracnose resistance response in Texas, Georgia, Florida, and Puerto Rico showed 27 accessions to be resistant across locations, while 145 accessions showed variable resistance response against local pathotypes. A genome-wide association study identified 16 novel genomic regions associated with anthracnose resistance. Four resistance loci on chromosomes 3, 6, 8 and 9 were identified against pathotypes from Puerto Rico, and two resistance loci on chromosomes 3 and 8 against pathotypes from Texas. In Georgia and Florida, three resistance loci were detected on chromosomes 4, 5, 6 and four on chromosomes 4, 5 (two loci) and 7, respectively. One resistance locus on chromosome 2 was effective against pathotypes from Texas and Puerto Rico and a genomic region of 41.6 kb at the tip of chromosome 8 was associated with resistance response observed in Georgia, Texas, and Puerto Rico. This publicly available SWDP and the extensive evaluation of anthracnose resistance represent a valuable genomic resource for the improvement of sorghum.

甜高粱因其汁液中易于提取的可发酵糖分，以及从秸秆中的纤维素多糖中获得的额外可发酵糖分，成为生产可再生化学制品和燃料的诱人原料。对于新型甜高粱种质资源的筛选，抗炭疽病（由半知菌亚门真菌病原体Colletotrichum sublineolum引起的病害）成为一项重要的选择标准。在甜高粱种质资源中识别出新的炭疽病抗性来源，为迅速培育新型抗性甜高粱种质资源提供了捷径。我们构建了一个包含来自美国农业部-农业研究服务局国家植物种质资源（NPGS）收藏的272份资源（包括来自22个国家的农家种和先进育种材料）的甜高粱多样性群体（SWDP），该群体代表了NPGS甜高粱收藏的约15%。SWDP的基因组特征分析识别出171,954个单核苷酸多态性（SNPs），平均每4,071 kb存在一个SNP。群体结构分析显示，SWDP可以划分为四个群体和一个混杂群体，并且这种群体结构可以与高粱的种族分类相对应。在德克萨斯州、乔治亚州、佛罗里达州和波多黎各进行的两年重复试验结果表明，27份资源在多个地点表现出抗炭疽病的特性，而145份资源则对当地病原型表现出不同的抗性反应。全基因组关联研究识别出与炭疽病抗性相关的16个新的基因组区域。在染色体3、6、8和9上分别鉴定出四个抗性位点，针对波多黎各的病原型；在染色体3和8上分别鉴定出两个抗性位点，针对德克萨斯州的病原型。在乔治亚州和佛罗里达州，分别检测到染色体4、5、6上的三个抗性位点和染色体4、5（两个位点）以及7上的四个抗性位点。染色体2上的一个抗性位点对德克萨斯州和波多黎各的病原型有效，而位于染色体8末端的一个41.6 kb的基因组区域与在乔治亚州、德克萨斯州和波多黎各观察到的抗性反应相关。这个公开可用的SWDP以及对其炭疽病抗性的广泛评估，为高粱的改良提供了宝贵的基因组资源。