The Research On Water Stress And Nutrient Stress Of Seedlings Of Zanthoxylum Ailanthoides Sieb. Et Zucc

This dissertation refer research material of fast-growth native broad leafed tree Zanthoxylum ailanthoides Sieb.et Zucc. Through varieties experiments of different water stress,different matches of nitrogen,phosphor and potassium fertilization, the paper made a systematic study on the change regulation of physiological index such as anti-oxidase, accretion,biomass,and photosynthetic physiologic parameters ect,then physiological regularity intimidated by water stress and growth and photosynthetic characteristics influenced by nutrient stress discussed and revealed, which will have important theory significant and applied producing significant for solving the problems of water management in Zanthoxylum ailanthoides Sieb.et Zucc.seedlings, and solving the problems of fertilization for enhancing productive force.(1) The varied conditions of activities of anti-oxidase and several physiological indexes of the Zanthoxylum ailanthoides Sieb.et Zucc. under water stress with the method of diping roots with various concentrations of Polyethylene glycol(PEG-6000) were discussed. The results indicated that activity of superoxide dismutase decreased conspicuously under different gradients of water stress, superoxide dismutase activity treated with Polyethylene glycol solution of 75 and 100 gram per liter had significant differences when compared to comparison; Catalase,peroxidase activities were increased under 50 gram per liter solution treatment,it indicated that oxidation resisting system of Zanthoxylum ailanthoides Sieb.et Zucc.had initiated, and catalase,peroxidase activities reached maximum when treated with 75 gram per liter solution, then both decreased under the solution of 100 gram per liter; Water stress resulted in membrane lipid peroxidation and the content of malonaldehyde and relative permeability of plasma membrane were increased; Neither the content of chlorophyll nor the activity of nitrate reductase decreased evidently when treated with the solution of 50 and 75 gram per liter, but the 100 gram per liter solution treatment had a significant difference; Both carotenoid and protein contents decreased notably under different gradients treatments;Proline content was low,and it increased significantly under 75 and 100 gram per liter solution treatments.(2) An experiment of fertilizer combinations of nitrogen, phosphor and potassium of three different levels was arranged to study effects of the combinations on growth and some physiological properties of potted Zanthoxylum ailanthoides Sieb.et Zucc.seedlings based on orthogonal experiment table L9(34) design. Among 9 disposals, the N2P1K2 combination was best for the ground diameter,and N2P3K1 combination was appropriate for the height growth. The N2P2K3 combination had a evidence influence on stem weight, root weight, leaf weight and leaf area.The N3P3K2 combination was best for the increase of chlorophyll content and photosynthesic rate.Based on total indexes,the treatment 2,3 increased small comparing to comparison; the treatment 4,5,6,7,8,9 had significant differences when compared to comparison.Ground on six indicators of ground diameter,seedling growth,stem weight,root weight,leaf weight and leaf area, the result of treatment 4,5,6 were higher than treatment 1,2,3,7,8,9, and chlorophyll content and photosynthesic rate increased all along due to the increasing of nitrogen, phosphor and potassium mixture ratio. Root/shoot ratio of treatment 1,2,3 were higher than treatment 4,5,6,7,8,9 conspicuously.(3) The experiment of different matchs of nitrogen, phosphor, potassium fertilization indicated that, the seedlings influnced by nitrogen largely.Nitrogen had evidence influences on 8 indicators of accretion, biomass and physiology, and exceeded the effects of phosphor and potassium obviously.Two of the 3 fertilizer element have high mutual effects on each indexes. Multivariate quadratic multinomial regression equation can be fitted based on data measured, then the proper amount of application of carbamide,calcium superphosphate and kali can be computed.(4) Diurnal variation of its photosynthesic rate and transpiration rate presented single peak curve in autumn or winter, both reached highest at midday 13:00. Stomatal factor resulted in photosynthesic rate increased quickly at a.m. and stomatal limitation exerted main function for the change of photosynthesic rate at midday and p.m..There were positive correlation among transpiration rate,photosynthetically active radiation,air temperature,leaf temperature and photosynthesic rate, and five indexes had synchronized change regular.Photosynthesic rate and intercellular CO2 concentration had obvious negative correlation, and water pressured deficits influenced by relative air humidity. Solar radiation had obvious effect on air temperature and leaf temperature, and relative air humidity affected by air temperature and light intensity markedly. (5) There were multivariat linear relations between photosynthesic rate and photosynthetic physiologic parameters.Regression models were established based on this linear relation:Pn=-53.94+1.225Tr-4.473Gs+0.002Ci-0.024Ca-0.001Par+8.814Vpl+ 0.661Rh-1.044 Tc+1.516T1+1.411WUE, the correlation coefficient was 0.953;stepwise regression equation:Pn=-10.234+1.572WUE+1.578Tr-0.011Ci+0.030Ca, multiple correlation coefficient was 0.936,and it indicated that Pn have a evident linear relationship with Tr, Ci, Ca and WUE. Principal component analysis of ten indexes influencing photosynthetic rate showed that solar radiation and air temperature can represent for the prime variable of primacy principal component approximately, and stomatal conductance can represent for the secondary principal component.