袁飞 刘子凡 廖道龙 高瞻 曹鑫鑫

摘 要：以自接冬瓜（SGwg）、自接南瓜（SGp）及南瓜嫁接冬瓜（Gwg）為材料，采用苗期接种法对植株抗病性进行比较，并通过平板试验分析其根系分泌物对冬瓜枯萎病菌菌丝生长的化感效应，同时采用GC-MS分析鉴定根系分泌物的成分和相对含量，为通过南瓜嫁接防治冬瓜枯萎病及开发植物源新农药提供理论依据。结果表明：（1）SGwg易感冬瓜枯萎病，Gwg与SGp高抗冬瓜枯萎病，且大田试验中Gwg的单瓜质量和小区产量明显高于SGwg;（2）Gwg和SGp根系分泌物对冬瓜枯萎病菌具有化感抑制作用，而SGwg根系分泌物对其具有化感促进作用;Gwg与SGwg的化感效果存在显著差异，而Gwg与SGp的化感效果差异不显著;（3）随处理时间的延长，Gwg根系分泌物的化感抑制效果明显增强，SGp的化感抑制效果变化不明显，SGwg的化感促进效果呈现逐渐下降的趋势;（4）嫁接植株根系分泌物的组成比自接南瓜和自接冬瓜均要丰富，且相对含量也与自接南瓜和自接冬瓜存在显著差异。综上所述，南瓜嫁接提高冬瓜枯萎病抗性的化感机制是嫁接改变了根系分泌物组成且含有抑制冬瓜枯萎病病菌菌丝生长的成分。

关键词：冬瓜;嫁接;枯萎病病菌;根系分泌物;分离鉴定

中图分类号：S642.3+S642.1 文献标志码：A 文章编号：1673-2871（2021）05-026-04

Allelopathymechanism of grafting with pumpkin rootstock on improving resistance to Fusarium wilt in wax gourd

YUAN Fei1， LIU Zifan1， LIAO Daolong2， GAO Zhan1， CAO Xinxin1

（1. College of Tropical Crops， Hainan University， Haikou 570228， Hainan， China; 2. Institute of Vegetables， Hainan Academy of Agricultural Sciences， Haikou 571100， Hainan， China）

Abstract： With self-grafted pumpkin（SGp）， self-grafted wax gourd（SGwg） and grafted wax gourd（Gwg）as materials， the growth of the Fusarium oxysporum of wax gourd were measured by using mycelial growth rate method， the disease resistance were identified by using the seedling inoculation method， and the chemical element of SGp， SGwg and Gwg root exudates were anlysized by GC-MS. The results showed that： （1）SGpand Gwg are highly resistant to Fusarium wilt， while SGwg is highly susceptible. Single fruit weight and the yield of Gwg were significantly higher than that of SGwg. （2）Root exudates（RE） of SGp and Gwg could inhibit the growth of the F. oxysporum， while the RE of SGwg could promote the growth. The allelopathy of Gwg has significantly difference with that of the SGwg， but it has not significantly difference with that of SGp. （3）With the extension of treatment time， the inhibition effect of RE from Gwg was significantly enhanced， but the inhibition effect of RE from SGp did not decline， and the promotion effect of RE from SGwg has a decline trend gradually. （4）RE in Gw have more divers chemical elements than that in SGpand SGwg， and there are remarkable differences of RE component among the SGp， SGwg and Gwg.In conclusion， the allelopathy mechanism of Gwg with highly resistant to Fusarium wilt was the variation of RE component in grafted plants which could inhibit the mycelial growth of F. oxysporum.

Key words： Grafted; Wax gourd; Fusarium oxysporum; Root exudate; Extraction and identification

冬瓜（Benincasa hispida （Thunb） Cogn.）是葫芦科冬瓜属一年生蔓性草本植物，是一种营养丰富的食疗保健蔬菜[1]。海南是我国重要的冬瓜生产和供应基地，2018年冬瓜种植面积高达7006 hm2[2]。随着冬季异常天气发生频率的加大，全国对海南冬季瓜的需求量会越来越大。……