| Sweet kernel apricot(Prunus armeniaca×sibirica)is Chinese characteristic and an important ecological,woody grain and oil tree at “Sanbei” area.Due to the law of utilization of nutrition is unclear in Sweet kernel apricot,the existing pattern of fertilization is extensive.The imbalance of nutrition utilization leads to low yield in Sweet kernel apricot.Under different yield levels,the article mainly investigates the relationship of soil and leaf nutrition through correlation analysis and principal component analysis.At the same time,the article also explores orthogonal fertilization and deficiency of nutrition diagnosis experiment through photosynthetic physiology and phenotypic traits,vegetative growth,and determination of leaf nutrient accumulation.The study establishes the foundation of precise fertilization and nondestructive of nutrient diagnosis.The preliminary research results are as follows:(1)Through the correlation analysis and principal component analysis of soil and leaf nutrition found that the soil nutriention had significant difference in 3 regions.However,the leaf total nitrogen,total potassium content had no significant difference.The leaf of total nitrogen and total phosphorus had extremely significant positive correlation.The soil of total phosphorus and the leaf of total nitrogen,total phosphorus had significantly positive correlation.The soil of total potassium and the leaf of total nitrogen,total phosphorus,total potassium had significantly positive correlation.The soil of available potassium and total nitrogen and total phosphorus in leaf also had significantly positive correlation.The nutrition of soil and leaf had significant difference under different yields.The main factors which influencing the yield of ‘youyi' were total nitrogen,available nitrogen in soil,and total nitrogen,total phosphorus,total potassium is the main factor in leaf.In high yield levels,the content of N,P,K in leaves were 18.33 mg·g-1(17.50 mg·g-1-19.48 mg·g-1),0.51 mg·g-1(0.29 mg·g-1-0.67 mg·g-1),21.83 mg·g-1(20.17 mg·g-1-25.04 mg·g-1).(2)The change of ‘youyi' phenotypic trait was different under different nutrients deficiency.When lacked of N,the traits of small blade,the veins fade out,the whole blade slightly yellow,and swallow were occurred.When lacked of P,the traits of young leaf yellow,margin with white spot were occurred.When lacked of K,new leaves occurred soft,and late period occurred yellow and curl,necrosis.When lacked of NP,the traits ofleaves occurred curl,necrosis,veins were very shallow and young leaves occurred thin and yellow.When lacked of NK,the traits of leaves occurred curl,necrosis,and leaf margin occurred white,and new leaves would become small and yellow.When lacked of PK,the traits of leaves occurred smaller and thinner,and curl upwards,and the central of leaves would become dark green.When lacked of NPK,withered old foliage edge dried up,and new leaves occurred curl,yellow,small,and thin.Under the condition of JS,the leaves occurred curl upwards,faded green,necrosis.On the basis of different deficiency symptom judge deficiency elements.(3)The effect of photosynthetic physiological indexes was different on deficiency of nitrogen,phosphorus and potassium.The decline of net photosynthetic rate was mainly affected by stomatal limitation(early)and nonstomatal limitation(later).In the process of nutrient deficiency,the scope of light application was more and more narrow,this is also one of the important reason for the decline of Pn.N deficiency can significantly reduce the absorption of phosphorus,and promoted the absorption of potassium.P deficiency reduced the absorption of phosphorus in a certain extent.K deficiency had no significance effect on the absorption of nitrogen and phosphorus.Therefore,the fertilization of sweet kernel apricot needed to note the interaction of nitrogen and phosphate fertilizer.Determining the content of leaf nutrition in the different nutrients deficiency periods applied the basis of nondestructive nutrition diagnosis and precise nutrient management.The content of N,P,K in leaves under the condition of normal growth were 18.81-32.13 mg·g-1,0.66-1.12 mg·g-1,25.23-29.35 mg·g-1,respectively.The data were totally accordanced with the nutrition of high yields levels in adult stage.When the contents of N,P,K in leaves were 22.23,0.46,13.70mg·g-1,the deficiency symptoms occurred in the early stage.However,when the contents of N,P,K in leaves were 11.52,0.31,8.50mg·g-1 respectively,the serious deficiency symptoms occurred.(4)The study investigated the ground and underground biomass,and root morphological characteristics on the deficiency of nitrogen,phosphorus and potassium.We found that the potash had significantly effect on the growth of the underground part,showing that the existing fertilization strategy was not scientific.The best fertilization strategy was nitrogen fertilizer priority with potash fertilizer.It could balance the development of ground and underground.At the same time,it could improve the resistance and the yield of ‘youyi'.(5)Different ratio of fertilization had significanctly effect on the growth of ‘youyi' and the different of influence nutrient elements were different.The most important nutrient on vegetative growth was nitrogen,and secondary order was potassium and phosphorus.The most important nutrient on photosynthetic physiological was nitrogen,and secondary order was phosphorus,and the last was phosphorus.The best ratio of fertilizer nitrogen was N(40 g),P(10 g),K(30 g),and organic fertilizer(400 g).It was similar with actual processing FT24(N(40 g),P(15 g),K(20 g),and organic fertilizer(400 g)).Under the FT24,the content of N,P,K in leaves were 19.91 mg·g-1,0.579 mg·g-1,32.06 mg·g-1,respectively.The data were accordanced with the nutrition of high yields levels in adult stage.Through the leaves of N,P,K at juvenile stage and adult stage showed that maintaining a certain levels(18.81-32.13 mg·g-1,0.66-1.12 mg·g-1,25.23-29.35 mg·g-1)of N,P,K in leaves could ensure high yield in juvenile stage. |
PDF Full Text Request