274个甘蔗常用亲本主要叶部病害和黑穗病的抗性评价

甘蔗优良亲本的选择和利用是决定甘蔗品种选育的关键因素,甘蔗亲本资源单个性状研究较多,但是,多种病害的综合性评价较少。为了解甘蔗亲本抗病性,优化甘蔗杂交亲本选择和组合,在广西农业科学院甘蔗研究所海南甘蔗杂交基地筛选常用甘蔗亲本274个,包括引进美国（US）15份、引进其他国家（GW）31份、引进中国台湾（TWCHN）25份、引进国内其他地区（GN）92份和自育亲本（GT）111份,进行甘蔗叶部白条病、叶焦病、赤腐病、轮斑病、花叶病、黄叶综合症（黄叶病）、梢腐病、黄斑病8种甘蔗叶片主要病害的抗病性评价和甘蔗黑穗病发病率调查,并利用灰色关联度分析锤度与中国甘蔗8个主要病害的关联度和亲本的抗病性加权关联度分析。结果表明,轮斑病是甘蔗常用亲本群体中发病最普遍的病害,有214个亲本发生病害,发病比例达78.10%,但其抗病级别7~9级只有9个亲本,总体感病程度较轻。亲本群体感病数最少的3个病害分别为白条病、梢腐病和黄斑病。美国和中国台湾是我国大陆甘蔗最重要的亲本来源地,已育成多个优良品种。美国引进亲本群体感染白条病、叶焦病和黄叶病的发病比例最高,分别为20.00%、33.33%和33.33%,但其他叶部病害的发病比例较低;中国台湾引进亲本群体中,轮斑病、黄叶病和叶焦病的发病比例较高;国内其他地区引进和自育亲本群体的发生病害比例较一致,属于中间水平,但自育亲本群体的轮斑病发病比例高达80.18%。黑穗病是中国大陆危害最严重的甘蔗病害。美国15个亲本群体的黑穗病发病比例为13.33%,且其中最大发病率仅为2.17%,属于感染亲本多但病害发病较轻;中国台湾引进亲本群体的黑穗病发病比例为24.00%,且其中最大发病率为10%,在各来源地亲本中发病率最高;甘蔗亲本叶部病害与锤度之间的相关性分析表明,其中梢腐病与锤度关联度最高为0.960,而黑穗病最低为0.711。灰色关联度加权分析常用亲本的抗病性表现为：F171、Tai98-2817、RB92-579、YuanL7、YueY R1、GF2、GT03-1462、GT08-120抗病性优良,而YZ99-596、CP01-1178、YunY06-450、CP94-1100、CP09-4256抗病性差。以欧式距离分类法对274个常用亲本的8个叶部病害和黑穗病进行模糊聚类分析,常用亲本可分为6类,其中第一类群是ROC28、MeiY8、YG45、YZ11-1204、GT05-1141和GT09-268,中抗轮斑病和黄斑病,高抗其他病害。本研究对甘蔗杂交亲本材料的选择和优化提供参考,对甘蔗育种材料的创制具有重要意义。

Resistance Evaluation of Main Leaf Diseases and Smut Diseases in 274 Commonly-used Sugarcane Parents

Sugarcane parental screening and utilization is a key factor of sugarcane variety breeding. Many researches were focused on single character evaluating in sugarcane parental resources, while few were studied on comprehensive diseases evaluating. To understand the resistance of sugarcane parents, and select parent for hybrid combination, 274 commonly-used sugarcane parents, including 15 from the United States (US), 31 from other countries (GW), 25 from Taiwan, China (TWCHN), 92 from mainland China (GN) and 111 form Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences (GT) in Hainan Sugarcane Hybrid Base, Guangxi Academy of Agricultural Sciences, were investigated by the incidence of sugarcane smut disease and evaluated 1-9 grade levels for disease resistance (1-3 grade for Resistance, 4-6 grade for Medium and 7-9 grade for sensitive) by visual evaluation on leaf scald disease, leaf scorch disease, red rot disease, ring spot disease, mosaic disease, yellow leaf disease, pokkah boeng disease and yellow spot disease of 8 main leaf diseases in China. Grey correlation degreed analysis and Fuzzy clustering were used to analyze the correlation relationship of Brix between smut disease and 8 main leaf diseases, and to evaluate the resistance of comprehensive diseases for sugarcane parents. Ring spot disease was the most popular in Guangxi commonly-used sugarcane parents by incidence of 78.10% and 214 parents were infected, but only 9 parents were in 7-9 grade disease resistance which was belonging to less harmful disease. Leaf scald disease, pokkah boeng disease and yellow spot disease were least infecting the parents. The parents from US and TWCHN were the most important parents for breeding in mainland China and had been used to breed many excellent progenies. US parents got the highest frequency of leaf scald, leaf scorch and yellow leaf disease by 20.00%, 33.33% and 33.33%, respectively. TWCHN parents had higher frequency rate on ring spot disease, yellow leaf disease and leaf scorch disease. GT and GN parents were belonging to the medium level in disease incidence, but ring spot disease incidence rate of GT parents was 80.18%. Smut disease was the most harmful disease in mainland China. The incidence frequency rate of smut disease of 15 US parents was 13.33% and the highest was 2.17%, belonging to popular infection but slight harm. However, TW parents were the highest in maximum incidence by 10.00% and highest frequency of 24.00% in all the parent regions. Brix was the highest by 0.960 in grey correlation degreed with pokkah boeng diseas, but the lowest by 0.711 with smut disease. Weighted grey correlation degreed analysis, a mathematical assessment model containing many factors, is effective to evaluate the comprehensive properties of crops or things. F171, Tai98-2817, RB92-579, YuanL7, YueY R1, GF2, GT03-1462 and GT08-120 showed high weighted correlation degreed and good disease resistance, and YZ99-596, CP01-1178, YunY06-450, CP94-1100 and CP09-4256 showed poor disease resistance. The 274 sugarcane parent could be classified into six groups by Fuzzy clustering on the incidence of smut disease and 8 leaf diseases. The comprehensive evaluation for the commonly-used sugarcane parent could be used to select parents for sugarcane hybrid with high disease resistance.