蒋欢 唐贵婷 吴朝君 张勇 彭玉梅 苏宇 赵冰峰 王旭祎

摘要 Zhihengliuella aestuarii B18是一株对十字花科根肿病菌Plasmodiophora brassicae具有抑制作用的优良生防菌株。为探明其生防潜能，本文通过抗生素抗性标记法、盆栽试验和田间小区试验研究了B18在不同土壤pH、土壤温度、土壤含水量、初始接种浓度、蔬菜作物以及不同土壤类型中的定殖动态。灭菌土试验結果表明：调节土壤pH 7.5～8.5，含水量10%～30%，放置于10～25℃，70 d后B18定殖菌量保持在105～107 cfu/g。盆栽试验结果表明：初始接种菌液浓度为109 cfu/mL时，45 d后根际土中定殖菌量可稳定在104～105 cfu/g。将50 mL浓度为2×109 cfu/mL的生防菌菌液接种于田间不同类型土壤后，第30天定殖菌量分别为病田8.7×105 cfu/g，病土1.02×105 cfu/g，健田8.5×104 cfu/g，健土2.6×104 cfu/g，即定殖能力由强到弱依次为：病田>病土>健田>健土。且病田中B18在根际土中可存活至45 d且菌量保持在104 cfu/g，根内可存活至31 d且菌量保持在104 cfu/g。田间调查结果显示B18在病田和病土中对榨菜根肿病的防效分别为4201%和47.53%，增产率分别为37.24%和40.22%。

关键词 生防菌; Zhihengliuella aestuarii B18; 定殖菌量; 根际土; 根肿病菌; 防效

中图分类号： S 436.344

文献标识码： A

DOI： 10.16688/j.zwbh.2020630

Analysis of the colonization ability and biocontrol efficacy of Zhihengliuella aestuarii B18 against clubroot disease

JIANG Huan， TANG Guiting， WU Chaojun， ZHANG Yong， PENG Yumei，

SU Yu， ZHAO Bingfeng， WANG Xuyi*

（Southeast of Chongqing Academy of Agricultural Sciences， Fuling 408099， China）

Abstract

Antagonistic Zhihengliuella aestuarii B18 is an excellent biocontrol strain which can inhibit Plasmodiophora brassicae. In order to explore its biocontrol potential， the colonization dynamics of B18 in different soil pH values， soil temperatures， soil water contents， initial inoculation concentrations， different vegetable crops and different soil types were studied by using antibiotic resistance labeling method and conducting pot experiments and field plot experiments. The results of sterilized soil test showed that， under the conditions of soil pH 7.5-8.5， water content 10%-30% and 10℃-25℃， the amount of colonized bacteria remained at 105-107 cfu/g after 70 days. The results of pot experiments showed that， when the initial inoculation concentration was 109cfu/mL， the amount of colonized bacteria in rhizosphere soil stably remained at 104-105 cfu/g after 45 days. When 50 mL of 2×109 cfu/mL biocontrol bacterial solution was inoculated in different soil types in the field， the amount of colonized bacteria on the 30th day was 8.7×105 cfu/g in the infected field， 1.02×105 cfu/g in the infected soil， 8.5×104 cfu/g in the healthy field， and 2.6×104 cfu/g in the healthy soil. These results indicated that， under different conditions， the colonization ability of B18 from strong to weak was as followed： infected field infected soil， healthy field and healthy soil. In the infected field， B18 could survive for 45 days in the rhizosphere soil with an amount of 104 cfu/g， and 31 days in the root with an amount of 104 cfu/g. The results of field investigation showed that B18 had control efficacy of 4201% and 47.53% against clubroot disease of mustard tuber in infected fields and infected soils， with yield increase rate of 37.24% and 40.22%， respectively.

Key words

biocontrol bacteria; Zhihengliuella aestuarii B18; colonization quantity; rhizosphere soil; Plasmodiophora brassicae; control effect

十字花科根肿病是由芸薹根肿菌Plasmodiophora brassicae Woron.引起的影响全球十字花科作物生产的土传病害[1]。在中国，根肿病常年危害面积占十字花科作物种植面积的 1/3以上，造成的产量损失达 20%～30%，发病严重田块产量损失可达 60%以上，有的甚至绝收[2-4]。根肿病菌是一种不可人工培养的专性寄生菌，病菌在土壤中存活时间长且有生理分化[5]，经土壤、种子、流水等传播，防治十分困难。国内外针对该病原菌进行了大量防治技术的研究，包括抗病品种选育[6]、农业和化学防治[7-8]和生物防治[9-10]，其中生物防治近年来越来越受到研究者的重视并初见成效。