公主岭霉素对草莓的防病诱抗和促生效应

Efficacy of gongzhulingmycin against powdery mildew caused by fungus Sphaerotheca aphanis and its effects on the growth of strawberry

为明确公主岭霉素在草莓生产中的防病诱抗效应,于大田采用五点取样法调查公主岭霉素对草莓白粉病的防控效果及对植株生长性状的影响,并于室内采用生测法测定其对草莓叶片防御酶活性和根际土壤酶活性的影响。结果显示,以公主岭霉素水浸提液100倍稀释液进行灌根并协同叶面喷雾对草莓白粉病的预防效果为71.90%;单独叶面喷雾对草莓白粉病的治疗效果为69.90%;灌根协同叶面喷雾预防与叶面喷雾治疗的综合防控处理对草莓白粉病的防治效果可达85.37%。公主岭霉素水浸提液100倍稀释液灌根后草莓幼苗的株高、叶柄长、叶长、叶宽、叶数、径冠等方面均优于清水对照;叶面喷施可提升叶片中多酚氧化酶和超氧化物歧化酶的活性,喷雾后1 d内即较清水对照显著提高;5 d后过氧化氢酶活性显著高于清水对照。灌根后根际土壤中蔗糖酶的活性在用药后15 d内均显著高于清水对照。表明合理施用公主岭霉素可实现对草莓白粉病的有效防控,并诱导提升草莓植株的抗病性,改善草莓生长环境,促进其生长。

In order to evaluate gongzhulingmycin(GZL) for management of powdery mildew caused by fungus Sphaerotheca aphanis in strawberry production, the efficacy of GZL against strawberry powdery mildew and its effect on plant growth characters of strawberry was investigated in field trials, and the effects of GZL on the enzyme activities in leaves and rhizosphere soil were assayed in the laboratory. The results showed that the preventive efficacy of prior-to-infection leaf-spraying and root-drenching with100×dilution of GZL water extract was 71.90% against strawberry powdery mildew while its curative efficacy of with post-infection leaf-spraying was 69.90%. The best efficacy could reach 85.37% with applying GZL before and after infection. The plant height, petiole length, leaf length, leaf width, the leaf number and crown diameter were increased for strawberry plants drenching with 100×dilution of GZL water extract compared to those of the negative control. The activities of polyphenol oxidase(PPO) and superoxide dismutase(SOD) in the leaves sprayed with GZL increased within one day after spraying,which was significantly higher than those of the control. By five days after inoculation, the activity of catalase(CAT) was also improved significantly. The activity of sucrase in rhizosphere soil was significantly higher than that of control within 15 days after root drenching. The results indicated that rational application of GZL could effectively prevent and control strawberry powdery mildew, enhance the disease resistance of strawberry plants, and promote the growth of strawberry.