鏈格孢（Alternaria alternata）在棗、梨和蘋果果實(shí)上的致病性分化研究

武海燕 李長水 馬慶周 尹新明 耿月華 張猛

摘? ? 要：鏈格孢（Alternaria alternata）可侵染多種果樹引起產(chǎn)前及產(chǎn)后果實(shí)黑斑病，造成嚴(yán)重的經(jīng)濟(jì)損失。不同果樹來源的鏈格孢是否能交互傳染還不清楚。本文探討了引起北方棗、梨和蘋果果實(shí)黑斑病的鏈格孢在這3種果實(shí)上的致病性分化和交互致病性，明確其交互傳染特性。從北方不同地區(qū)果園采集棗、梨和蘋果的黑斑病病果樣品，通過組織分離法進(jìn)行病原菌的分離， 然后進(jìn)行純化及鑒定。利用離體果實(shí)接種法對分離到的各個病菌分別在棗、梨、蘋果的果實(shí)上進(jìn)行致病性測定，分析了其致病性的差異。結(jié)果顯示：從3種病果實(shí)上共分離出45株鏈格孢，其中對棗、梨和蘋果表現(xiàn)出強(qiáng)致病性的分別為5、11、7株，表現(xiàn)為弱致病的分別為17、8、20株；對3種果實(shí)的致病性均在次強(qiáng)等級以上的有6株，致病性均為弱等級的有3株，而在3種果實(shí)上致病性等級表現(xiàn)為次強(qiáng)等級以上的菌株有30株，占到總菌株的66.6%。總之，棗、梨和蘋果病果上的鏈格孢存在致病性分化現(xiàn)象，并在這3種果實(shí)上是可以交叉侵染致病，互為侵染源。因此，在病害防治方面，臨近的不同果園對黑斑病需聯(lián)防聯(lián)治。

關(guān)鍵詞：鏈格孢；致病性分化；交互致病性

中圖分類號：Q939.5? ? ? ? ?文獻(xiàn)標(biāo)識碼：A? ? ? ? ? DOI 編碼：10.3969/j.issn.1006－6500.2023.05.009

Abstract：? Alternaria alternata could infect many kinds of fruit trees and cause black spot disease in fruits before and after production， which would cause serious economic loss. It is not clear whether the pathogens of different fruit trees can interact with each other. In this paper， we studied the pathogenicity differentiation and cross pathogenicity of the fungi that causes black spot in jujube， pear and apple fruits? investigated in northern China.? Black spot fruit samples of jujube， pear and apple were collected from orchards in different areas of north China and the pathogenic fungi were isolated by tissue separation method， then， they were purified and identified. The pathogenicity of each isolated pathogen was determined on the fruits of jujube， pear and apple by in vitro inoculation method， and the difference of pathogenicity was analyzed. The studies showed that 45 strains were isolated from the three kinds of fruits， among which 5， 11 and 7 strains showed strong pathogenicity to jujube， pear and apple， and 17， 8 and 20 showed weak pathogenicity， respectively. There were 6 strains with sub-strong pathogenicity and 3 strains with weak pathogenicity， and there were 30 strains with sub-strong pathogenicity and above on 3 kinds of fruits， accounting for 66.6% of the total strains. In summary，there was pathogenicity differentiation in the pathogens of jujube， pear and apple black spot. They could be cross-infected on these three kinds of fruits， which are mutual infection sources. Therefore， in terms of disease control， joint prevention and treatment are needed in different near by orchards.

Key words： Alternaria alternata; pathogenic differentiation; interactive pathogenicity

鏈格孢（Alternaria alternata）屬于半知菌鏈格孢屬（Alternaria），是一種廣泛存在于土壤、空氣、工業(yè)材料、植物上的腐生菌，更是一種重要的植物病原真菌，其寄主范圍和地理分布廣泛，其導(dǎo)致的病害給農(nóng)作物的生長和農(nóng)產(chǎn)品的貯運(yùn)造成巨大的損失[1-3]。……