Abstract:

This paper studied the effect of raw garlic extract on controlling Phytophthora capsici and pepper
Phytophthora blight by determining indoor toxicity and field efficacy．Results showed that raw garlic extracted from
different parts had good inhibitory effect on P. capsici．The higher concentration was，the stronger inhibition was．
The inhibitory effect of crud extracts from garlic bulb on the growth of P. capsici could reach 100.00% under 150.0
mg·mL^-1 concentration．As incubation time went on，the inhibition effect decreased gradually．The results of
pot experiment indicated that different concentration of all part of garlic extracts had certain control effect on P.
capsici．When the concentration of garlic extract from bulb reached 150 mg·mL^-1，and the controlling effect
could reach 59.38%．Results of GC-MS determination showed that there were 20，19 and 23 kinds of volatile
components in garlic root，stem and leaf，and bulb，mainly organic sulfur，accounting for over 90% of the
total volatile substance．But，there were distinct differences between composition and content．When pure
methylpropyl disulfide，diallyl sulfide，diallyl disulfide and diallyl trisulfide were added into the medium，the
growth of P. capsici was significantly inhibited．The best inhibition rate was 60.55% with 100 mg·L^-1 of diallyl
trithioether．Rotation and companion planting pepper with garlic could effectively control pepper Phytophthora
blight and the controlling effects were 59.81% and 62.09%，respectively．All these results indicated that garlic
volatile substance had a good application prospect in controlling P. capsici．

Key words: Garlic, Crude extract, Pepper Phytophthora blight, Component identification, Control effect

摘要：

采用室内毒力测定与田间防效试验研究大蒜粗提物对辣椒疫病菌的抑制作用及对病害的控制效果。结果表明，大
蒜不同部位粗提物均对辣椒疫病菌有很好的抑制作用，浓度越高抑制作用越强，特别是鳞茎粗提物，在150.0 mg·mL^-1 浓
度下，对辣椒疫病菌生长抑制率达100.00%。随着培养时间的延长，各粗提物对辣椒疫病菌的抑制作用下降。盆栽试验结果
表明，不同浓度大蒜各部位粗提物对辣椒疫病均有一定的控制效果，大蒜鳞茎粗提物浓度为150.0 mg·mL^-1 时，防效可达
59.38%。GC-MS 测定结果表明，大蒜根、茎叶和鳞茎粗提物中分别有20、19 和23 种挥发性物质，均以有机硫化物为主，
占总挥发性物质的90% 以上，但其组成成分和含量有明显差别。向培养基中加入硫醚类有机硫化物纯品，对辣椒疫病菌的
生长均有明显抑制作用，其中100 mg·L^-1 二烯丙基三硫醚对辣椒疫病菌的抑制效果最好，达60.55%。与大蒜轮作或混栽可
有效降低辣椒疫病的病情指数，防效分别达59.81% 和62.09%。这些结果说明大蒜挥发性物质在辣椒疫病的绿色防控上有很
好的应用前景。

关键词: 大蒜, 粗提物, 辣椒疫病, 成分鉴定, 控制作用