不同人参灰霉病的灰葡萄孢菌生物学特性及致病性比较

摘要

In order to explore the causes of recently endemic ginseng gray mold, biological characteristics and pathogenicity of 16 Botrytis cinerea isolates from different hosts and regions were compared. The results showed that the effects of different conditions on the mycelium growth of B. cinerea strains were significant. On the same condition, differences were significant in mycelium growth among the tested strains except light. The optimum media for the growth of all strains included PDA and PSA. PSA was the optimum medium for the mycelium growth of isolates PJAR1, PJAL3, PYCL1 and PJLL1; PDA was the optimum medium for the mycelium growth of isolates FSYL1, PJAL1, PJAL2, PYLL1, PBLL1, PQAL1, PHLL1 and LSYF1; while PSA was the optimum for other strains. Temperatures for mycelium growth of each tested isolate ranged from 5℃ to 25℃. The optimum temperature of mycelium growth of the isolates FSYL, PJLL2, PRHL1, PHLL1 and LSYF2 was 25℃, while that for others was 20℃. The ranges of pH for mycelium growth of the tested isolates were the same, from 3 to 11. As for mycelium growth of PYCL1 and LSYF2, the favorable pH value was 6; the optimum pH of mycelium growth of the isolates (PJAR1, PJAL2, PJAL3 and PYLL1) was 4; while that for the other isolates was 5. The optimum carbon sources of mycelium growth were glucose and maltose. The favorable nitrogen sources of mycelial growth of the tested isolates were yeast extract, beef extract and peptone. There was no significant effect of light on the mycelium growth of B. cinerea strains. The results also showed that all tested isolates could cause grey mould on Panax ginseng. However, there was difference in pathogenicity among the different isolates from the same host, and the pathogenicity difference was not obviously related to the localities of the isolates. Pathogenicity of sporutation as well as mycelial strains were relatively weak. According to diameters of the lesions, the pathogenicity of the all isolates was classified into three categories. Strong virulent strains were PJAR1, PJAR2, PJAL2 and LSYF1; intermediate virulent strains were PJLL1, FSYL1, PHLL1, PRHL1, PBLL1, PQAL1 and PJLL2; and weak virulent strains were PJAL3, LSYF2, PJAL1, PYCL1 and PYLL1.%为了探究人参灰霉病新流行成因,对来源不同寄主和地区的16株灰葡萄孢(Botrytis cinerea)菌株的生物学特性及致病力进行比较。结果表明：供试菌株在PDA和PSA培养基上生长较好,PJAR1、PJAL3、PYCL1和PJLL1最适培养基为PSA,FSYL1、PJAL1、PJAL2、PYLL1、PBLL1、PQAL1、PHLL1和LSYF1最适培养基为PDA,其余菌株最适培养基为查氏培养基；菌丝生长温度范围均为5~25℃,FSYL1、PJLL2、PRHL1、PHLL1和LSYF2最适生长温度为25℃,其余菌株在20℃时生长最快；供试菌株在pH值3~11的范围内均能生长,PYCL1和LSYF2菌丝最适生长pH值为6,PJAR1、PJAL2、PJAL3和PYLL1最适生长pH值为4,其余菌株最适生长pH值为5；菌丝生长最适碳源为葡萄糖和麦芽糖；菌丝生长最适氮源为酵母膏、牛肉膏和蛋白胨；光照对菌丝直径影响不显著。接种供试灰葡萄孢菌株后均能引起人参叶片发病,但来自相同寄主的菌株间致病力也存在差异,按病斑大小可将供试菌株划分为强致病力菌株(PJAR1、PJAR2、PJAL2和LSYF1)、中等致病力菌株(PJLL1、FSYL1、PHLL1、PRHL1、PBLL1、PQAL1、PJLL2)和弱致病力菌株(PJAL3、LSYF2、PJAL1、PYCL1和PYLL1)。