苹果轮纹病室内快速评价体系的建立

A rapid laboratory evaluation system for apple ring rot

为探索高效、稳定且操作简便的苹果轮纹病室内评价方法,选用分离菌株Slq0803-1-1-1菌饼分别对离体富士苹果两年生枝条以及当年生嫩梢、叶片和成熟果实4种材料进行接种,并对试验结果和接种方法进行比较分析。结果显示,在有伤和无伤条件下各接种材料接种无菌PDA块均不发病,接种病菌仅在有伤情况下致病;枝条烫伤接种发病最慢且病斑最小,嫩梢针刺1针接种较叶痕接种发病明显;1针及10针刺伤接种叶片正、反面,正面1针刺伤接种发病较快且一致;果实去除果皮接种较1针、10针刺伤后接种发病显著。用4个致病力不同的菌株验证,发现4种离体材料均能验证不同菌株间的致病力差异,且结果与田间无伤接种当年生新梢一致。说明4种离体材料均可准确、快速评价苹果轮纹病,其中正面针刺1针接种叶片的方法最优。

To develop an efficient,stable and easy method for disease evaluation,excised 2-years old twigs,current-year shoots,expanded leaves and mature fruits of ＇Fuji＇ apple tree were inoculated with the plugs of isolate Slq0803-1-1-1.The results showed that lesions only occurred on the samples inoculated by the fungus with wound;samples with/without wound and inoculated with plain PDA plug were lesion free.The effects of materials and types of wound on lesion size presented that lesions formed on the twigs which treated by burning before inoculation were smaller and formed later than others;lesions on the young shoots with one pricking wound were bigger than those on the leaf scars;leaves were easier to be infected by pricking one time on the upper sides than lower ones even with ten times pricking wounds;lesions on fruits inoculated after peeling were bigger than treated with pricking.Furthermore,to verify the stability of the laboratory-test evaluation system,four isolates with different virulences were tested through inoculating on both excised materials and shoots in the field.The results showed that all the four excised materials could present the differences in virulence among strains,and the conclusions were consistent with field inoculation on shoots without wound.Therefore,all these four excised materials could be used to evaluate the pathogenicity of Botryosphaeria dothidea accurately and rapidly for laboratory-test,among which the excised leaf treated by one-time-pricking on the upper side before inoculation was the best option.