水稻重测序核心种质资源的稻瘟病抗性鉴定与评价

稻瘟病一直是制约水稻产量的重要因素之一,稻瘟病抗源筛选是抗性基因挖掘和抗病育种的基础。本试验利用3000份(简称3K)重测序中的1217份核心种质资源,通过湖北恩施两河和芭蕉2个病圃自然诱发鉴定抗性,结合不发病条件下农艺性状考察和抗病资源的苗期人工接种抗谱测定,综合评价和筛选优异的稻瘟病抗源。自然诱发鉴定结果显示材料间的稻瘟病抗感差异显著,从中共获得144份抗苗瘟、叶瘟和穗瘟的抗病种质。选用稻瘟病综合抗性较好的34份材料以30个不同来源的稻瘟病菌株苗期接种,鉴定显示有17份材料的抗性频率≥70%,抗谱较广。农艺性状考察结果显示,大部分抗病材料植株偏高,单株产量低,农艺性状差。结合病圃鉴定、人工接种鉴定和农艺性状考察,鉴定出7份稻瘟病抗性强、抗谱广且农艺性状较好的优异抗源材料IRGA 411-1-6-1F-A、YJ30、金早47、泉珍10号、YN 1353-3、云粳23和IRAT1047,可作为抗源亲本用于稻瘟病抗性基因挖掘和品种抗稻瘟性改良。

Identification and Evaluation of Blast Resistance for Resequenced Rice Core Collections

Rice blast is one of the key factors that restrict rice yield, and screening blast resistance resources is a basis work for mining blast resistance genes and breeding resistant varieties. A set of 1217 accessions selected from 3000 (3K) re-sequenced rice core collection were comprehensively evaluated for blast resistance in two natural disease nurseries at Lianghe and Bajiao in Enshi area and agronomic traits in disease-free field as well as resistance spectrum of resistant accessions at seedling stage. There were significant differences in response of different accessions to rice blast. Among them, a total of 144 accessions with blast resistance at different growing stages were obtained. Thirty-four accessions with relatively high comprehensive blast resistance were inoculated with 30 diverse isolates, showing that 17 accessions with a broad resistance spectrum (≥70%). According to the investigation of agronomic traits, most resistant accessions had high plant height, low grain yield per plant and poor agronomic traits. Finally, seven accessions with high blast resistance, broad resistant spectrum and relatively good agronomic traits were selected, including IRGA 411-1-6-1F-A, YJ 30, Jinzao 47, Quanzhen 10, YN 1353-3, Yunjing 23, and IRAT 1047, were identified. Those resistant accessions can be used in mining resistance gene and variety improvement for blast resistance.