山茶种质资源的花腐病抗性评价

Evaluation of Resistance to Flower Blight of Camellia Germplasm Resources

[目的]建立山茶种质资源花腐病抗性评价技术,评价山茶种质资源对花腐病的抗性水平。[方法]采用3份抗性不同的种质资源设置时间梯度,分析接种山茶叶杯菌菌丝块后不同培养时间对抗性评价的影响;计算接菌后山茶种质资源病斑的相对面积和病情指数,制定花腐病病情严重度的分级标准和抗性评判标准,建立山茶种质资源花腐病抗性评价技术;利用该技术评价56份种质资源对花腐病的抗性。[结果]接种菌丝块于山茶种质资源的离体花瓣,并在接菌后72 h统计病斑的相对面积,能准确地对山茶种质资源进行抗病性评价。56份种质资源抗性评价结果表明,8份种质资源为免疫或高抗花腐病、24份种质资源为中抗、14份种质资源为中感、10份种质资源为高感。山茶属不同组间种质资源的抗性水平不同,同一组内不同种间以及同一亲本的不同杂交组合之间的抗性水平也有差异。[结论]本研究建立了山茶花腐病抗性评价技术,明确了56份山茶种质资源花腐病的抗性水平,筛选出了8份免疫或高抗花腐病的种质资源。

[Objective]To develop the evaluation technology for flower blight resistance of Camellia germplasm resources and evaluate the resistance levels of Camellia germplasm resources to flower blight.[Method]The time gradient of three germplasm resources with different resistance was used to analyze the effects of different culture time on the resistance evaluation after inoculating the hyphae plug of Ciborinia camelliae.We calculated the relative area of lesion and disease index of Camellia germplasm resources after inoculation,formulated the severity grading criteria and resistance evaluation criteria,and established the resistance evaluation technology of Camellia germplasm resources to flower blight.This technique was used to evaluate the resistance of 56 germplasm resources to flower blight.[Result]Inoculating hyphae plug on the detached petals of Camellia germplasm resources,and calculating the relative area of lesions at 72 hours after inoculation,could accurately evaluate the disease resistance of Camellia germplasm resources.The results of resistance evaluation of 56 germplasm resources showed that 8 germplasm resources were immune or highly resistant to flower blight,24 germplasm resources were medium resistant,14 germplasm resources were medium susceptible,and 10 germplasm resources were highly susceptible.Resistance levels among different sections of Camellia germplasm resources were different,and the resistance levels of different species within the same sections and different crosses of the same parent were also different.[Conclusion]In this study,resistance evaluation technology of Camellia germplasm resources to flower blight has been established.The resistance level of 56 germplasm resources was identified,and 8 germplasm resources with immune or highly resistant to flower blight were screened out.