西瓜枯萎病菌的鉴定及申嗪霉素对其防效评价

由于重茬西瓜种植面积增多,西瓜枯萎病的发生面积逐步扩大,严重影响了西瓜生产。本研究用PDA培养基从中国农业科学院郑州果树研究所大棚温室萎蔫枯萎的西瓜上分离病原菌。形态学鉴定为尖孢镰刀菌;ITS序列分析表明其与西瓜枯萎病菌的序列一致性达到99%;发现该菌引起西瓜枯死严重,发病率达96.7%以上。因此,证实是西瓜枯萎病菌引起的。为了防治该病害,进行了温室和室内的申嗪霉素药效评价。室内抑菌实验和温室内药剂处理结果一致,1%申嗪霉素100倍防治效果最好,抑菌率达76.03%,灌根防治率达58.86%。因此,生产上建议在西瓜枯萎病发病早期使用1%申嗪霉素100倍连续3次灌根,每次间隔约8天左右,尽可能减少西瓜枯萎病菌对西瓜的影响。

Identification of Fusarium Wilt of Watermelon and Efficacy Evaluation of Shenqinmycin

With the increase of watermelon planting area, the occurrence area of watermelon wilt disease is gradually expanding and seriously affecting watermelon production. The fungus in the study was isolated from the root of wilt watermelon by PDA medium in the greenhouse of Chinese Academy of Agricultural Sciences Zhengzhou Fruit Research Institute. It was identified as Fusarium oxysporum by the morphological analysis, the sequence character and the pathogenicity analysis. The sequence was 99% identified with the Fusarium oxysporum f. sp. niveum, the mortality rate of watermelon was 96.7%. So it was confirmed that the pathogen was watermelon Fusarium wilt. To control the disease, the efficacy evaluation of Shenqinmycin was also carried out. The results were consistent with indoor bacteriostasis and field test in the greenhouse. The best control effect was 1% Shenqinmycin 100 times, the inhibition rate was 76.03% in PDA medium, the control rate in greenhouse was 58.86%. In order to reduce the losses caused by Fusarium wilt on watermelon, it was advised that 1% Shenqinmycin 100 times could be used for Fusarium wilt control in the field at the early time of the disease occurrence.