The Mitigating Effect Of “Jincunqiu” Foliar Fertilizer On Fusarium Wilt Of Strawberry

With the adjustment of agricultural industry,the cultivation scale of strawberry in our country is getting larger and larger.However,due to the difficulties of rotation and stubble in large-scale production areas,the problem of strawberry continuous cropping is becoming more and more serious,strawberry growth and development is poor,growth period is delayed,and soil-borne diseases are aggravated.At the same time,Fusarium wilt is common due to the relatively high humidity environment of protected cultivation,which seriously affects the yield and quality of strawberry.5-Aminolevulinic acid(ALA),a new plant growth regulator,is the main active ingredient of “Jincunqiu” amino acid foliar fertilizer.In this experiment,‘Benihoppe’ strawberry(Fragaria × ananassa Duch.cv.‘Benihoppe’)plants were used as materials to explore the mitigating effect of “Jincunqiu” amino acid foliar fertilizer on strawberry disease by physiological and pathological experiments.We found that Trichoderma harzianum had obvious inhibitory effect on the growth of Fusarium oxysporum,and then took T.harzianum as a starting point to systematically study the relationship among “Jincunqiu”,T.harzianum and F.oxysporum and their role in alleviating Fusarium wilt in order to provide a new theoretical basis for the application of “Jincunqiu” foliar fertilizer in strawberry production.The main results are as follows.1.Sick potted strawberry leaves were sprayed with clear water,“Thiophanate-Methyl”,“Jincunqiu” and “Jincunqiu + Thiophanate-Methyl”,respectively.After 30 days,the related indexes of leaves,petioles and root tips of different treatments were determined.The results showed that the disease had a serious inhibitory effect on the growth of strawberry,but different mitigating effects appeared after three treatments of “Thiophanate-Methyl”,“Jincunqiu” and “Jincunqiu + Thiophanate-Methyl”.Among them,the effect of “Jincunqiu+ Thiophanate-Methyl” was the most significant,which showed significantly higherleaf size,petiole length,relative content of chlorophyll and photosynthetic performance of leaves than other treatments.These results showed that “Jincunqiu + Thiophanate-Methyl”significantly inhibited the disease of strawberry plants,improved the photosynthetic performance of strawberry plants and promoted the growth of strawberries.2.In order to explore the control effect of “Thiophanate-Methyl”,“Jincunqiu” and“Jincunqiu + Thiophanate-Methyl” on strawberry diseases in the production process,strawberry plants in greenhouse were sprayed and clear water was used as control.The results showed that there was no obvious disease in strawberry among different treatments30 days after treatment.However,the growth degree of strawberry plants treated with“Jincunqiu” was significantly higher than that of control.At the same time,after determining the related indexes of strawberry fruit,it was found that the contents of soluble solids,soluble sugar,vitamin C,soluble protein and anthocyanin were significantly higher than those of other treatments.These results showed that “Jincunqiu” treatment significantly improved strawberry fruit quality and economic value,and also had a certain degree of control effect on strawberry field diseases.This provides a theoretical basis for its application in strawberry production in greenhouse.3.The petiole of sick strawberry was inoculated into Potato Dextrose Agar(PDA)solid medium,and three kinds of fungi were isolated,namely Trichoderma(T.harzianum),Fusarium oxysporum(F.oxysporum)and Aspergillus fumigatus(A.fumigatus).Among them,the former is probiotic,and the latter two are pathogenic bacteria,especially Fusarium oxysporum,which is the main pathogen of Fusarium wilt.They were inoculated on different PDA plates containing “Thiophanate-Methyl”,“Jincunqiu”,“Jincunqiu + Thiophanate-Methyl”and so on.The results showed that in the basic medium,Trichoderma grew slowly,Fusarium oxysporum and Aspergillus fumigatus grew faster.“Thiophanate-Methyl” completely prevented the growth of three kinds of fungi,while “Jincunqiu” foliar fertilizer promoted the growth of Trichoderma and inhibited the growth of Fusarium oxysporum and Aspergillus fumigatus.If Trichoderma was co-cultured with Fusarium oxysporum and Aspergillus fumigatus,and different concentrations of “Jincunqiu” solution were added,it was found that Trichoderma could significantly inhibit the growth of Fusarium oxysporum,and the appropriate concentration of “Jincunqiu” solution could further enhance this effect.the highest inhibition rate was 90.40%.Trichoderma had similar antagonistic effect on Aspergillus fumigatus and was promoted by “Jincunqiu” solution.These results suggest that the appropriate concentration of “Jincunqiu” treatment may inhibit the growth of pathogens and the occurrence of Fusarium wilt by promoting the growth of Trichoderma.