灌溉消毒水源对香蕉植株生长和可培养微生物数量的影响

Effects of irrigating disinfectant water on the banana plant growth and the number of cultivable microorganisms

[目的]探究灌溉消毒水源对香蕉植株生长和可培养微生物数量的影响,以期为香蕉枯萎病的防控提供新的思路和方法。[方法]首先通过灌溉水消毒试验获得最优的消毒剂及其使用浓度,再进一步采用盆栽试验,探究草地土壤和香蕉连作土壤上灌溉消毒水源对病原菌和其他可培养微生物数量及香蕉植株生长的影响。[结果]相比于过氧化氢和氨水,次氯酸钠具有最优的病原菌消毒效果,原液稀释4 000倍后病原菌消毒效率仍为100%。灌溉消毒水源能有效改善香蕉植株的生长状况,与灌溉含病原菌水源相比,灌溉消毒水源处理中香蕉植株的株高、茎粗、叶面积、植株鲜质量和植株干质量在草地土中分别高出7.57%、15.96%、30.89%、21.36%和61.58%,在蕉园土中分别高出12.10%、29.58%、32.15%、51.18%和63.60%;灌溉含病原菌水源导致尖孢镰刀菌在土体、根际和根内显著富集,在草地土壤和连作蕉园土中的病原菌数量分别为灌溉消毒水源处理的2.32、3.26、3.13倍和1.68、2.53、1.62倍;同时,灌溉消毒水源提高了土体土壤细菌和真菌数量的比值(B/F),改变了土壤和香蕉根际可培养微生物的群落结构。[结论]灌溉含病原菌水源加快了病原菌在香蕉根际的传播和富集,通过灌溉水消毒能够有效减缓病原菌富集,控制病原菌的传播,研究结果为枯萎病的综合防控提供了新思路。

[Objectives]Effects of irrigating disinfectant water on banana plant growth and number of cultivable microbes were investigated in this study for providing a new strategy for the control of banana fusarium wilt disease.[Methods]In this study,the optimal disinfectant was firstly obtained through the comparation of sterilizing effects of different disinfectants on the irrigation water containing different concentrations of Fusarium oxysporum,and then the pot experiments which utilized soils collected from the grass land and banana monoculture field were performed to explore the influence of irrigation disinfectant water on the number of F.oxysporum and other cultivable microbes as well as on the growth of banana plants.[Results]Compared to hydrogen peroxide and ammonia water,sodium hypochlorite was the best disinfectant,and after the dilution of the original solution for 4 000 times,the disinfection efficiency against the pathogen of this disinfectant was still 100%.Irrigating disinfectant water could effectively improve the growth of banana plants,and compared to the irrigation with water containing F.oxysporum,the plant height,stem diameter,leaf area,shoot weight and shoot dry weight in the treatment irrigated with disinfectant water increased by 7.57%,15.96%,30.89%,21.36%and 61.58%in grassland soil,and 12.10%,29.58%,32.15%,51.18%and 63.60%in banana garden soil.Irrigation water containing pathogens significantly enriched F.oxysporum in soil,rhizosphere and roots,and the number was 2.32,3.26,3.13 times in grassland soil and 1.68,2.53,1.62 times in continuous cropping soil as big as that from the treatment irrigated with disinfectant water;in addition,irrigating disinfectant water improved the ratio of the number of bacteria and fungi in soil,and altered cultivable microbial community structure in bulk soil and banana rhizosphere.[Conclusions]Irrigation with water containing F.oxysporum accelerated the diffusion and enrichment of pathogen in banana rhizosphere,and spread of pathogen can be controlled by irrigation of sterilized water.The results are expected to provide new ideas for the comprehensive prevention and control of banana fusarium wilt disease.