【摘要】 近年来,尽管西瓜产业不断发展壮大,但轮作土壤种植西瓜易产生枯萎病害导致世界范围内的西瓜严重减产。通过对峙培养实验和抑菌实验探讨了重阳木内生真菌司氏角担子菌(Ceratobasidum stevensii)B6菌株对西瓜枯萎病病原菌尖孢镰刀菌西瓜专化型(Fusarium oxysporum f. sp.Niveum,FON)的拮抗作用,并初步分析了其作用机制。平板拮抗试验的结果表明,内生真菌B6生长过程中不是通过产生抑菌带来抑制FON菌丝,而是利用自身的生长优势将FON完全覆盖。显微观察B6与FON菌丝的接触部位,发现FON菌丝外侧附着B6顶端菌丝形成的胞样结构,表明FON菌丝生长仅受到B6菌丝的抑制。抑菌试验结果显示,B6产生的挥发性物质可以抑制FON的生长和产孢,并使其菌丝分枝明显减少;B6的发酵液对FON的生长和产孢没有抑制作用。因此,推测B6主要通过释放某些挥发性物质产生拮抗作用而抑制FON的生长。更多还原

【Abstract】 In recent years, although the watermelon industry has developed and grown steadily, yet it is easy to produce serious wilt disease caused by continuous cropping soil and resulted in falling in production of watermelon. In this study a confrontation experiment and inhibition experiment were adopted to investigate the antagonism of endophytic fungus Ceratobasidum stevensii(B6) of Bischofia polycarpa against Fusarium oxysporum f. sp. Niveum(FON), and initially analyzed the effective mechanism. The results of plate antagonistic experiment showed that the endophytic fungus B6 did not inhibited FON hyphae through producing inhibition zone during its growth, but totally covered the mycelium of FON by its own growing superiority. It was found under microscopic observation that at the contact location between B6 and FON hyphae an appressoria-like structures were formed at the end hyphae of B6, indicated that the growth of FON hyphae was only inhibited by B6 hyphae. The inhibition experiment results showed that volatile substances produced by B6 could inhibit the growth of FON and sporulation, and made the mycelium branches obviously reduced, however, the fermentation broth of B6 did not have inhibition effects against the growth and spore production of FON. Therefore, it is inferred that B6 mainly inhibits the growth of FON by releasing antagonistic volatile substances.更多还原