大蒜与烤烟轮作对烟草黑胫病的防治效果及作用机理初探

Control effects of tobacco and garlic rotation on tobacco black shank and a preliminary study on the inhibition mechanism

为探讨大蒜和烤烟轮作对烟草黑胫病的防治效果,本试验研究了大蒜根系分泌物及主要成分对烟草黑胫病菌的影响。结果表明,大蒜根系分泌物能显著抑制游动孢子的游动及休止孢的萌发;大蒜根系分泌物中的苯并噻唑和2种含硫化合物二烯丙基二硫醚、烯丙基甲基二硫醚对烟草黑胫病菌菌丝生长均具有较强的抑菌活性,其抑制活性均随着供试浓度增加而增强。从而证实:大蒜和烤烟轮作可以通过大蒜的根系分泌抑菌物降低烟草黑胫病的发生和危害,实现病害的生态防控。

Control effects of tobacco and garlic （Allium sativum） rotation on tobacco black shank for four consecutive years were monitored and the antimicrobial activity of garlic root exudates and its contained compounds against Phytophthora parasitica var. nicotianae were analyzed. Results demonstrated that incidence of tobacco black shank was significantly reduced after rotation with garlic, and tobacco production was also significantly improved. Root exudates secreted by garlic could inhibit zoospore motility and cystospore germination. Benzothiazole, diallyl disulfide ether and methyl allyl disulfide ether, contained in the root exudates of A. sativum, showed strong inhibitory activity against mycelium growth of P. parasitica vat. nicotianae, and inhibitory activity was dose-dependent. Garlic rotated with tobacco not only effectively control occurrence and damage of tobacco black shank, but also increase tobacco yield, partly due to the antifimgal activity ofA. sativum root exudates, which are useful to achieve ecological control of tobacco diseases.