【摘要】 【目的】评估离体叶片接种法对冬瓜疫病抗性鉴定的可行性,建立一种快速高效的冬瓜疫病抗性鉴定方法,并筛选抗疫病的冬瓜和节瓜品种,为培育及利用抗病品种提供参考。【方法】以注射灌根接种法为对照,采用离体叶片接种法对9份冬瓜品种进行抗病性鉴定和比较,评估离体叶片接种法的可行性;并采用所建立的离体叶片接种法对23份冬瓜品种和18份节瓜品种进行抗病性鉴定,从中筛选抗、耐疫病的冬瓜和节瓜品种。【结果】离体叶片接种后,发病症状主要表现为叶片呈现暗绿色水渍状病斑,后期变成黑色病斑,有的会长出白色霉层。9份供试冬瓜品种中,铁柱168、B184和P33等7份冬瓜品种分别采用两种方法进行抗感性评价,反应类型结果完全一致。两种鉴定方法对冬瓜疫病的抗性鉴定结果一致性高达77.78%:注射灌根接种法发病率的平均值是54.6%,病情指数的平均值是29.6;离体叶片接种法发病率的平均值是60.2%,病情指数的平均值是31.5。对两种接种法的发病率和病情指数进行相关性分析,结果表明注射灌根接种法和离体叶片接种法的相关性达极显著水平(P<0.01),两种接种方法的发病率与病情指数相关系数分别为0.953和0.993。节瓜普遍比冬瓜更抗疫病,初步筛选出3份高抗冬瓜品种,分别是连环杂交大冬瓜、铁心999黑皮冬瓜和黑娃四号小冬瓜,病情指数分别为5.9、9.2和1.7;5份高抗节瓜品种,分别是佳庆338节瓜、玲珑节瓜、翠秀节瓜、新粤农8号和5号黑毛节瓜,病情指数分别为4.2、5.0、5.8、6.7和7.5。【结论】与注射灌根法相比,离体叶片接种法具有发病症状明显、操作方便、速度快、不伤害植物等优点,离体叶片接种法可作为冬瓜品种疫病抗病性鉴定的辅助手段,用离体叶片接种法筛选出3份高抗冬瓜品种和5份高抗节瓜品种可作为培育及利用抗病品种的资源。更多还原

【Abstract】 【Objective】To evaluate the feasibility of in vitro leaves inoculation method and establish a rapid and efficient method for the identification of wax gourd[Benincasa hispida(Thund.)]Phytophthora blight resistance,and then screen the wax gourd and chieh-qua(B. hispida var.chieh-qua)varieties that resistant to Phytophthora blight,which provided references for breeding and utilization of disease-resistant varieties.【Method】The disease resistance of nine varieties of wax gourd were identified and compared by in vitro leaves inoculation and with injection irrigation root inoculation method as control. The feasibility of in vitro leaves inoculation method was evaluated. Moreover,23 varieties of wax gourd and 18 varieties of chieh-qua were identified for disease resistance through in vitro leaves inoculation,from which disease-resistant wax gourd and chieh-qua varieties were screened out.【Result】The disease symptoms after in vitro leaves inoculation were dark-green watermark on the leaves at initial stage,which turned into black spot at the later period,and some would develop white fungal mycelium. Among the nine wax gourd varieties tested,seven varieties had the same reaction type results by the two inoculation methods,such as Tiezhu 168,B184 and P33,etc. The two identification methods had the same disease resistance identification results of 77.78% on wax gourd varieties. The mean values of disease incidence and disease index of injection irrigation root inoculation were 54.6% and 29.6,respectively. The mean values of disease incidence and disease index of in vitro leaves inoculation were 60.2% and 31.5 respectively. Correlation analysis was performed on the incidence and disease index of the two inoculation methods,and the correlation between the two methods reached extremely significant level(P<0.01). The correlation coefficient between incidence and disease index of injection irrigation root inoculation and in vitro leaves inoculation were 0.953 and 0.993. Chieh-qua was generally more resistant to Phytophthora blight than wax gourd. Three disease-resistant wax gourd varieties were preliminarily screened out,which were Lianhuanzajiao wax gourd,Tiexin 999 black wax gourd and Heiwa 4 small wax gourd,with the disease indexes of 5.9,9.2 and 1.7 respectively. Five disease-resistant chieh-qua varieties were selected out,including Jiaqing 338 chieh-qua,Linglong chieh-qua,Cuixiu chieh-qua,Xinyuenong 8 chieh-qua and No.5 black chieh-qua,with the disease indexes of 4.2,5.0,5.8,6.7 and 7.5,respectively.【Conclusion】Compared with injection irrigation root inoculation,in vitro leaves inoculation method has the advantages of obvious symptoms,convenient operation,fast speed,and no harm to plants,etc.,which can be used as an auxiliary method for disease resistance identification of wax gourd varieties. Three wax gourd varieties and five chieh-qua varieties with high disease resistance can be used as disease-resistant resources for breeding and utilizing.更多还原