Effect Of Biochar On Growth And Physiological Characteristics Of Cherry(Prunus Pseudocerasus ‘Manaohong')

Karstic mountain areas in Guizhou characterize in thin soil and low organic matter,which severely constrains the growth and development of Prunus pseudocerasus‘Manaohong'.Biochar is a poorly soluble solid substance produced by high temperature thermal cracking of agricultural and forestry wastes under anoxic or anaerobic conditions.It has the characteristics of large specific surface area and high porosity,and considerably possesses high water and fertilizer retention capacity.Prunus pseudocerasus‘Manaohong',recently bred in Guizhou,is an excellent cultivar with long shelf life,and the growing area is around 13,333 hm² in Guizhou.In the present study,three kinds of biochar,i.e.apple branches,tobacco stalks and corn stalks,were used in one-year-old plant of cherry,and the effects of biochar types and amounts on plant growth and physiological characteristics were investigated.The main results are as follows:1.The application of apple branches,tobacco stalks and corn stalks diversely promoted the growth and development of Prunus pseudocerasus‘Manaohong'plant.Among the growth indicators,the plant height,stem diameter,new shoot length,leaf number,leaf area,above-ground and below-ground biomass of cherry were significantly enhanced,and the promotion effect of 3%dosage?30g for each kilogram soil?was better than that of 6%,among which 3%tobacco stalks gave the most significant effect on the aerial part of plant.2.Effects of biochar on soluble sugar content,soluble protein content,photosynthetic rate?Pn?,transpiration rate?Tr?,stomatal conductance,intercellular CO₂ concentration and leaf nutrient content varied depending on types and dosages.3%tobacco stalks increased the soluble sugar content,soluble protein content,Pn and Tr by 12.31%,6.62%,51.48%and 111.33%,respectively in comparison with that of the control.The mineral nutrient content fluctuated,and there were some differences among different treatments.During the whole growth period,the P content in the leaves decreased first and then increased,the K content increased first and then decreased,the Ca content increased gradually,the N content showed a tendency to decreased-increased-decreased-increased and the contents of Mn and Zn showed a tendency to decreased-increased-decreased.3.There were significant differences in root morphology and physiological indexes under different biochar treatments.Biochar promoted the growth of total root length,root volume,total root surface area,total root volume,root tip number and number of branches,increased IAA,GA₃ and ZT contents,decreased root diameter and ABA content.During the growth period,the root activity showed a trend of increased-decreased-increased.Overall,biochar is beneficial to growth and development of roots.4.Biochar had a certain inhibitory effect on root cancer.The resistance of different biochars to plant of root cancer is YM6?6%corn stalks?>P6?6%apple branches?>P3?3%apple branches?>Y6?6%tobacco stalks?>Y3?3%tobacco stalks?>YM3?3%corn stalks?>CK?control?.5.Correlation analysis was carried out between the growth index and physiological index of Prunus pseudocerasus‘Manaohong'.The root fresh weight was significantly positively correlated with plant height,leaf area,shoot fresh weight and root length,and total root volume and root tip number were extremely significant.Soluble protein was negatively correlated with P,Mg and Mn contents.The N content was positively correlated with K content,and significantly negatively correlated with Ca and Mg contents.The K content was negatively correlated with Ca,Mg and Mn contents,and the Ca content was positively correlated with Mg and Mn contents.Principal component analysis of all indicators was carried out to select 12 indicators,and the membership function method analysis showed that the 3%tobacco stalks had the best effect on the growth and development of Prunus pseudocerasus‘Manaohong'.