Tang Xin, Zhang Jin-Qiang, Jiang Wei-Ke, Yuan Qing-Song, Wang Yan-Hong, Guo Lan-Ping, Yang Yang, Yang Ye, Zhou Tao
Guizhou University of Traditional Chinese Medicine Guiyang 550025, China.
National Resource Center for Chinese Meteria Medica, China Academy of Chinese Medical Sciences Beijing 100700, China.
Zhongguo Zhong Yao Za Zhi. 2022 May;47(9):2288-2295. doi: 10.19540/j.cnki.cjcmm.20220223.102.
Brown rot is a common disease in the cultivation and production of Gastrodia elata, but its pathogens have not been fully revealed. In this study, the pathogenic fungi were isolated and purified from tubers of 77 G. elata samples with brown rot. Pathogens were identified by the pathogenicity test and morphological and molecular identification. The pathogenicity of each pathogen and its inhibitory effects on Armillaria gallica were compared. The results showed that 119 strains of fungi were isolated from tubers of G. elata infected with brown rot. Among them, the frequency of separation of Ilyonectria fungi was as high as 42.01%. The pathogenicity test showed that the pathogenicity characteristics of six strains of fungi were consistent with the natural symptoms of brown rot in G. elata. The morphological and molecular identification results showed that the six strains belonged to I. cyclaminicola and I. robusta in the Nectriaceae family of Sordariomycetes class, respectively. Both types of fungi could produce pigments, conidia, and chlamycospore, and the growth rate of I. cyclaminicola was significantly higher than that of I. robusta. The comparison of pathogenicity showed that the spots formed by I. cyclaminicola inoculation were significantly larger than those of I. robusta inoculation, suggesting I. cyclaminicola was superior to I. robusta in pathogenicity. The results of confrontation culture showed that I. cyclaminicola and I. robusta could signi-ficantly inhibit the germination and cordage growth of A. gallica. A. gallica also inhibited the growth of pathogens, and I. cyclaminicola was less inhibited as compared with I. robusta. The results of this study revealed for the first time that I. cyclaminicola and I. robusta were the pathogens responsible for G. elata brown rot.
褐腐病是天麻栽培生产中的常见病害，但其病原菌尚未完全明确。本研究从77份患有褐腐病的天麻块茎中分离纯化致病真菌。通过致病性试验、形态学和分子鉴定对病原菌进行鉴定。比较了各病原菌的致病性及其对蜜环菌的抑制作用。结果表明，从患有褐腐病的天麻块茎中分离出119株真菌。其中，间座壳属真菌的分离频率高达42.01%。致病性试验表明，6株真菌的致病性特征与天麻褐腐病的自然症状一致。形态学和分子鉴定结果表明，这6株真菌分别属于粪壳菌纲间座壳科的仙客来间座壳和强壮间座壳。两种真菌均能产生色素、分生孢子和厚垣孢子，且仙客来间座壳的生长速率显著高于强壮间座壳。致病性比较表明，接种仙客来间座壳形成的病斑显著大于接种强壮间座壳形成的病斑，表明仙客来间座壳的致病性强于强壮间座壳。对峙培养结果表明，仙客来间座壳和强壮间座壳均能显著抑制蜜环菌的萌发和菌索生长。蜜环菌也能抑制病原菌的生长，且与强壮间座壳相比，仙客来间座壳受到的抑制较小。本研究结果首次揭示仙客来间座壳和强壮间座壳是导致天麻褐腐病的病原菌。
