向日葵菌核病田间接种方法及品种抗病性研究

为建立有效的向日葵菌核病田间接种鉴定方法，本研究以菌核病菌菌丝体悬浮液和高粱粒菌丝体作为接种物，分别对不同抗感向日葵品种在始花期和盛花期进行人工接种，从而筛选出最佳接菌物类型、浓度及接种时期，并用此方法对52个品种进行抗性评价。试验结果表明：两种接种物均可使向日葵感病品种产生盘腐症状。用菌丝体悬浮液接种时，7.5~15.0 g/L浓度即可区分出向日葵品种间抗感性差异。始花期接种较盛花期可获得更高的发病率及病情指数。同时筛选出5个对盘腐型菌核病表现抗病的向日葵品种。本研究所建立的田间接种方法能够有效地对向日葵进行抗菌核病筛选和鉴定，可用于向日葵抗菌核病育种。 

Methods of inoculation of Sclerotinia sclerotiorum on sunflower heads under field conditions for resistance evaluation

The objective of the study was to establish a rapid and effective technique of inoculating sunflower heads with Sclerotinia sclerotiorum in field condition. In this experiment, the inoculation period, the best inoculum and its concentration used for inoculation of sunflower head rot in field condition were screened, and their disease resistance was evaluated in 52 cultivars in the same way. The results showed that both inocula could make the susceptible variety to generate typical heads rot symptom. The differences between resistant and susceptible varieties of sunflower could be distinguished by the inoculum concentration with 7.5 to 15.0 g/L in PDA mycelium suspension inoculation. The effect of inoculation (DSI and morbidity) in beginning flowering stage was better than that in full-bloom stage. At the same time, 5 sunflower varieties with resistance to S. Sclerotiorum were screened out by this technique. The method for evaluation of resistance to S. sclerotiorum in the field condition could effectively identify the pathogenicity of S. sclerotiorum and screen the resistance to S. sclerotiorum for sunflower breeding.