Study On Solid-State Fermentation Of Trichoderma Harzianum T-E5 Conidia And Growth Promoting Effect Of Its Bio-Organic Fertilizer On Cucumber

Trichoderma,a widely distributed rhizosphere plant growth promoting fungi in the environment,is capable of promoting plant growth and enhancing crop yields.In this research,we carried out a series of researches on the screeing of solid-state fermentation substrate;the improvement of fermentation condition of spore production;the effects of both Trichoderma fermentation products and its bio-fertilizer on promoting plant growth;the effects of Trichoderma fermentation extracts on promoting hydroponic and pot-cultured cucumber.The main research results are as follows:1.The wheat straw are chosen to be the substrate of fermentation from the five different agricultural solid waste(wheat straw,maize straw,rice straw,bran and bean pulp).Solid plate state fermentation was suitable for production of conidial spore of T-E5.The single factor condition optimization was as follows:The wheat straw powder was prepared by inoculated with 3%(v/w)of 1×107 mL-1 T-E5 spore suspension prior to the acidification with nitric acid solution(0.1mol/L);the initial moisture content was kept at 75%.Under those conditions,fermentation with addition of exogenous urea and corn powder were incubated at 28 ℃ for 8 days,the maximum number of T-E5 conidial spores reached 8.87×109 per gram of dry matter.By the orthogonal optimization,the optimization condition was that 18.3ml 0.05 mol/L of nitric acid,9%(v/w)of inoculation amount,1%(w/w)of urea were added to every lOg of wheat straw with 70%(wet basis)of water content at 30 ℃ shallow dish and fermented for 8 days,the amount of Trichoderma conidia reached to 1.1×1010 per gram of dry matter.2,Pot experiments for two seasons indicated that the Trichoderma with chemical fertilizer and its bio-organic fertilizer promoteed the plant growth.Compared with chemical fertilizer(CCK)treatment,co-treatment with Trichoderma and chemical fertilizer showed the significant plant growth promoting effects,with the dry weight of aboveground plants increased by 13.3%and 15.3%in two seasons respectively;compared with organic fertilizer(OCK)treatment,Trichoderma bio-organic fertilizer showed remarkable plant growth promoting effects in the second experiment season,increased the plant height by 6.5%。And ertigation of fermentation extracts increased the dry weight of aboveground plants by 25.7%and 20.4%in two seasons,respectively;spraying of fermentation extracts increased the dry weight of aboveground plants by 16.5%and 12.1%in two seasons respectively;co-treatment with fertigation of fermentation extracts and organic fertilizer increased the plant height by 25.4%,co-treatment with spraying fermentation extracts and organic fertilizer increased the plant height by 13.6%.Trichoderma fertilizer and its bio-organic fertilizer both increased the amount of Trichoderma and the fungi in soil and in rhizosphere.Co-treatment with Trichoderma and chemical fertilizer significantly increased soil available phosphorus and available potassium content;the available phosphorus content significantly increased in Trichoderma bio-organic fertilizer treatment.3.Hydroponic experiments in three seasons all showed that Trichoderma fermentation extracts promoted the growth of cucumber efficiently.Compared with control(CK),the fermentation extracts treatment can better increase the cucumber dry matter than the treatment with spore solution solely.Fermentation extracts treatment significantly increased the dry weight by 21.7%,53.3%,50.2%,respectively,in three seasons;spore solution treatment increased the dry weight by 20.6%,48.4%,34.9%,respectively,in three seasons;and the filtrate of the fermentation extracts increased the dry weight by 15.1%,25.5%,15.0%,respectively in three seasons.4.Fertigation pot experiment results showed that:compared with control(CK),fermentation extracts treatment,spore solution treatment and filter solution treatment increased the plant height by 22.5%,19.3%,8.5%respectively,the aboveground dry weight increased by 10.8%,15.4%,20.7%respectively.Additionally,fermentation extracts treatment significantly increased the number of Trichoderma and fungi in soil,while spore solution treatment only increased the number of the fungi in soil.Irrigation pot experiment results showed that:compared with control(CK),fermentation extracts treatment,spore solution treatment and filter solution treatment increased the plant height by 12.3%,19.3%,8.5%respectively,the aboveground dry weight increased by 10.8%,15.4%,20.7%respectively.Additionally,fermentation extracts treatment only increased the number of Trichoderma and fungi in soil.