The Research On Mitigative Effects Of Biochar On Peach Replant Disease

To investigate the effect of biochar on replant disease,’Mao tao’and one-year old ’Kanoiwa’ were used for pot trials in our current experiment to study the different amount of addition of biochar (0,1%,2%) into replant soil on growth of peach seedlings, soil phsical and chemical properties and soil enzyme activeties. As for the results of our experiment, they can be summarized as follows:l.The effect of continuous cultivation on growth of peach seedlings and the physical and chemical properties of soil. Throughout the whole growing season, the plant height and stem diameter of’Mao tao’ seedlings under the RS treatment were all lower than those of seedlings treated with NS; Compared with the NS treatment, the fresh weight, dry weight, P and K content of ’Mao tao’seedlings under RS treatment were all siginificantly decreased. The available N, P and K content of replanted soil were all significantly lower than those of nonreplanted soil.2.The effect of biochar on growth of peach seedlings. Biochar had no significant effect on the dry matter accumulation of ’Mao tao’seedlings in replant soil, but it significantly decreased the dry weight of seedlings planted in nonreplant soil with the increasing addition of biochar. The P and Mg content of peach seedlings in replant soil with the addition of biochar were significantly higher than those of seedlings in replant soil without biochar, even more, the K content of peach seedlings under RS+1%C treatment was higher than that of peach seedlings under RS and NS treatment. The addition of biochar in nonreplant soil didn’t significantly increase the content of N and P, however the K content of peach seedlings decreased under NS+2%C treatment compared with NS treatment. Meanwhile, the addition of biochar in replant soil could significantly increase the uptake of N, P, K, Ca, Mg of’Kanoiwa’, and nonreplant soil added with biochar treatment increased the N, P content in ’Kanoiwa’ with the increasing biochar amount but the K, Ca content showed the opposite result.3.The effect of biochar on physical and chemical properties and enzyme activities of soil. The organic matter, available P, K content and pH value of replanted soil added with biochar were all higher than those of replanted soil without biochar, even more, the organic matter content in replanted soil added with biochar was significantly higher than that of nonreplant soil, and the available K content of replant soil with2%biochar and planted with’Kanoiwa’ increased by14.17%compared with that of nonreplant soil without biochar. Besides, Compared with NS treatment, the organic matter content and pH value of nonreplanted soil with1%and2%biochar were all significantly increased, meanwhile, the addition of2%biochar to nonreplanted soil had a significant effect on the available P and K content. However, biochar had no obvious effect on the available N content of replanted soil and nonreplanted soil.Biochar could significantly increase the catalase, urase and sucrase activities of replant soil planted with both’Mao tao’ and’Kanoiwa’, and catalase and urase activities were all significantly increased with the increasing application of biochar. Catalase activity of replanted soil with2%biochar was significantly higher than that of nonreplant soil without biochar. Biochar, to a certain degree, inhibited the acid phosphatase activity of the soil. Compared with replant soil without biochar, the acid phosphatase activity of replant soil added with1%and2%biochar and planted with ’Mao tao’ seedling decreased by1.84%and11.82%respectively, and the acid phosphatase activity of nonreplant soil with2%biochar decreased by11.32%compared with that of nonreplant soil.