Study On Allelopathy、Mechanism Of The Extracts Of Celery Root Material On Fusarium Oxysporium F.sp. Cucumerinum And The Field Investigation Of The Allelopathy

Under the condition of culture medium, treated with distilled water、acetone andethanol extracts of fresh celery root and root soil on Fusarium Oxysporium f.sp.Cucumerinum to study the allelopathy; treated with the extracts once the first leaf ofcucumber was5cm wide, to research the allelopathy mechanism on FusariumOxysporium f.sp. Cucumerinum; and research the field investigation of FusariumOxysporium f.sp. Cucumerinum treated with celery root, the results were as follows:1. The study on the allelopathy of extracts of fresh celery root and root soilAfter treating with the extracts of fresh celery root and root soil, theconcentrations were smaller than the control, the allelopathic effects were allpole-strength, the ethanol extract of root treatment was the smallest one, theallelopathic effects was the most pole-strength.2. The study on the allelopathy mechanism of extracts of fresh celery root androot soil on Fusarium Oxysporium f.sp. CucumerinumThe cell wall-degrading enzymes (pectinase、cellulase、β-glucosidase) activity、the intracellular protective enzyme (SOD、POD、CAT) activity、fusarium acid wereall lower than the control. The ethanol extract of root treatment was the lowest one，with the greatest declines of31.16%、43.87%、13.05、27.19%、49.85%、35.75%、42.74%、36.44%, respectively. For the different treatments, the best inhibition effectwhich were processed by the acetone extracts, the fresh root extracts were higher thanroot soil extracts distinctly.3. The study on the allelopathy mechanism of extracts of fresh celery root androot soil on cucumber seedlings(1) The nitrogen metabolites of the cucumber leaves were changed after treatwith the extracts of fresh celery root and root soil. After aqueous extracts treatment,contents of soluble protein、Arg、Pro、ammonia and NR were higher than that of thecontrast, and the acetone extract of root treatment was the highest one, with thehighest increases over the acetone control by10.58%、6.54%、3.10%、9.64%、18.30%and7.79%, there were negatively correlated between them with disease resistance;and the contents of Gly、Met、Phe and nitrate were lower than that of the contrast, for Gly、Phe and nitrate the acetone extract of root treatment was the lowest one, with thegreatest declines of3.41%、1.42%and7.52%, for Met the ethanol extract of roottreatment was the lowest one, with the lowest declines in the acetone controlby21.65%, there were positively correlated between them with disease resistance.(2) The phenoics metabolites of the cucumber leaves were changed after treatwith the extracts of fresh celery root and root soil. After aqueous extracts treatment,contents of phenol content and the enzymes activities were higher than that of thecontrast, and the acetone extract of root treatment was the highest one, with thehighest increases over the acetone control by10.01%、7.24%、6.79%、20.45%、34.87%、15.72%, Phenoics metabolites indexes was negatively correlated with diseaseresistance.(3) The defense enzymes and the cell wall-degrading enzymes activities of thecucumber leaves were changed after treat with the extracts of fresh celery root androot soil. After aqueous extracts treatment, activities of SOD、POD、chitinase、β-1,3-glucanase were higher than that of the contrast, the acetone extract of roottreatment was the highest one, with the highest increases over the acetone control by22.46%、31.44%、13.30%、31.50%, there were negatively correlated between themwith disease resistance; The activities of CX and IAAO were lower than that of thecontrast, the lowest treatment was acetone extract of root, with the greatest declines of8.24%、6.74%, the correlation analysis showed that CX and IAAO were positivelycorrelated with disease resistance.(4) The sugar content of the cucumber leaves were changed after treat with theextracts of fresh celery root and root soil. After aqueous extracts treatment, thecontents of reducing sugar and soluble sugar were higher than that of the contrast, theacetone extract of root treatment was the highest one, with the greatest increases by22.86%and22.63%, the sugar content was negatively correlated with diseaseresistance.(5) For the different treatments, the most significant effects were caused by theacetone extracts, and then the ethanol extracts, the last was by the distilled waterextracts; the fresh root extracts were higher than root soil extracts distinctly.4. The study on the field investigation of Fusarium Oxysporium f.sp.Cucumerinum treated with celery(1) Inoculation with Fusarium Oxysporium f.sp. Cucumerinum in the clear earth,Three treatment were established, treated with the extracts of fresh celery root and root soil、celery-cucumber was designed as crop rotation treatment and mixed withdried celery root, they could significantly reduce the disease incidence and diseaseindex, showed strong allelopathic inhibitory effect, with celery crop rotation effect isbest, the disease rate was7.69%, the disease index was4.33%, the inhibition rate was67.95%.(2) Under the condition of continuous cropping, use the extracts of fresh celeryroot and root soil、crop rotation with celery and mixed with dried celery root, theycould significantly reduce the disease incidence and disease index cucumber, showedstrong allelopathic inhibitory effect, with celery crop rotation effect is best, thedisease rate was5.63%, the disease index was3.87%, the inhibition rate was71.63%...