作物根际和叶围中产几丁质酶微生物的分布及其抑制真菌作用

STUDIES ON THE CHITINASE PRODUCING MICROORGANISMS AT CROP RHIZOPSPHERE AND PHYLLOSPHERE AND THEIR ANTIFUNGAL ACTIVITIES

从几十种作物的根际和叶围分离获得３５０株微生物，其中细菌和放线菌分别为２００株和１５０株。对所有这些分离物进行了抑制真菌试验和几丁质酶活性测定。在抑菌试验中，以棉花枯萎病菌、棉花黄萎病菌、黄瓜枯萎病菌，及西瓜枯萎病菌作为供试病原菌，有９６个分离物对其中的一种或一种以上的病原菌有抑制作用，其中１８个分离物对这４种病原菌都具有强烈的抑制作用。在几丁质酶活性方面，１０％的细菌和４０％的放线菌都能不同程度地产生几丁质酶。有些菌株几丁质酶活性强，抑菌作用也明显，有些菌株几丁质酶活性弱，抑菌作用弱或无作用，少数菌株几丁质酶活性强，但却无抑菌作用。用几丁质酶液处理病原菌孢子。

Three hundred and fifty isolates of bacteria and actinomyces were obtained from the rhizosphere and phyllosphere of various crops.Of them,96 showed inhibiting a ctivity to the growth of several crop pathogenic fungi in the laboratory bass.Th e percent of the isolated bacteria and 40% of the actinomyces produced chitinase on chitin plate.The chitinase activity appeared to be related to certain degree to the antifungal ability of the isolates.Treatment of spores of the pathogens with a solution of the chitinase produced by some isolates resulted in reduction s of the spore germination rate and length of the germ tubes.