蓝莓茎溃疡病病原菌鉴定及品种抗病性研究

Identification of causative agent of blueberry stem canker and screening of the disease resistant cultivars

在浙江及福建蓝莓产区发现一种蓝莓茎部病害,病斑呈棕黄色至棕黑色,严重时引起蓝莓整株枯死。对病样进行分离得到具有致病性的36个分离株。通过对菌株的形态学研究及系统发育分析,将致病菌鉴定为Diaporthe hongkongensis,本文系国内外首次报道D.hongkongensis危害蓝莓。对代表菌株的生物学特性进行研究表明:菌落生长最适温度为25℃;最适培养基为PDA;菌落生长对光照不敏感。采用菌饼刺伤接种活体枝条的方法对10个蓝莓主栽品种进行抗病性测定,结果显示:不同蓝莓品种对该病菌表现出敏感差异,其中‘爱国者’、‘瑞卡’、‘日出’、‘奥林匹亚’、‘都克’、‘托柔’、‘蓝丰’相对抗病;‘北陆’、‘埃利奥特’、‘达柔’相对感病。

A type of blueberry stem canker with yellow-brown or black-brown color, causing even whole plant death, was found in blueberry growing region from Zhejiang and Fujian province. A total of 36 pathogenic strains isolated from the symptomatic stems was identified as Diaporthe hongkongensis based on morphological characteristics and molecular phylogenetic analysis, which is the first report of D. hongkongensis causing diseases on blueberry. The further tests for the representative strain showed that the optimal growth temperature was 25~C, and PDA was the best growth medium while light was not necessary. The result of resistance test with the inocu- lum of mycelia discs on live-branches wounded by needle, showed that the ten of main blueberry varieties performed different level of sensitivity in which ＇ Patriot＇, ＇ Reka＇, ＇ Sunrise＇, ＇ Olympia＇, ＇ Duke＇, ＇ Toro＇, and ＇ Bluecrop＇ were relatively resistant, while ＇ Northland＇, ＇ Elliott＇, and ＇ Darrow＇ relatively susceptible.