Study On Nutritional Characteristics And Fertilization Of Rubber Somatic Embryo Seedlings

Rubber somatic embryo seedling is a rubber anther somatic cell plant induced by the anther culture technique.It has the advantages of high yield,strong resistance,strong resistance to powdery mildew,etc.It is currently a rubber planting variety promoted by China.However,there are few studies on related nutrition and fertilization,and lack of a reasonable fertilization program.Therefore,it is impossible to maximize the growth advantage of seedlings.In this paper,Reyan 7-33-97 rubber somatic embryo seedlings were selected,through the "3414" pot experiment and field experiment,the nutrient absorption,distribution,N/P value,nutrient efficiency and leaf annual nutrifertilization ent of vegetative organs of young trees were studied.Physiological characteristics and nutrient uptake of various vegetative organs,nutrient accumulation characteristics of saplings and NPK fertilizer utilization.The nutritional characteristics and fertilization effects of rubber somatic embryo seedlings were studied,and the ratio of fertilizers that promoted the seedlings was obtained,which provided a theoretical reference for guiding in the future.The main results are as follows(1)The distribution of total nitrogen,total phosphorus and total potassium nutrient concentrations in the different vegetative organs under of rubber saplings was found to be K>N>P on unwoody stems and on the other organs is N>K>P;Inside,the total nitrogen and total phosphorus concentration of the leaves were the highest,and the total potassium concentration of the petiole was the highest.(2)Combined with biomass considerations,total nitrogen accumulation was the highest in leaves,total phosphorus and total potassium accumulation were the highest in fully lignified stems,and were lowest in lateral roots;The nutrient accumulation showed N>K>P in all vegetative organs and plants(3)The N/P value of the vegetative organs in the saplings are all below the lower limit of the critical value.It indicates that the growth is limited by nitrogen,and a large amount of nitrogen fertilizer needs to be added(4)In the annual dynamic change of NPK nutrient content in rubber sapling leaves,the total nitrogen content increased and then decreased,the total phosphorus content did not change much,and the total potassium content showed a downward trend.The average annual NPK nutrient content was 3.27%,0.26%and 0.99%,in which the N and K contents are at normal levels,and P is at a high level.And the order of NPK nutrient content is N>K>P.(5)Among the NPK nutrient utilization rates of rubber saplings,the nutrient utilization rate of the main root was the highest;nitrogen and phosphorus were lower on the leaves,and potassium was lower on the petiole;The NPK nutrient utilization rate of all vegetative organs and plants was P>K>N,and only P>N>K on un-ligninized stems.(6)The NPK nutrient ratio required for the production of 100 kg of dry matter in young trees without fertilization is about 17:3:9.(7)In the "3414" pot experiment,the plant height,ground diameter,dry weight of each vegetative organ and total biomass of the Reyan 7-33-97 rubber somatic embryo seedlings were observed within a certain fertilization range,both increased with the application of nitrogen,phosphorus and potassium fertilizers.And fertilization treatments are greater than no fertilization treatment.It is concluded that the plant height is higher under the treatment of N2P2K1,the ground diameter is higher under the treatment of N1P2K2,and the biomass is higher under the treatment of N1P2K2.(8)The chlorophyll content of rubber somatic embryo seedling increased first and then decreased with the increase of nitrogen,phosphorus and potassium fertilizer under different fertilization formula ratios,and the best fertilizer formula is N1P2K1.(9)The total nitrogen,total phosphorus and total potassium contents of the vegetative organs and plants of rubber somatic embryo seedlings were higher than those of the non-fertilizer treatment N0P0K0 under different fertilization formula ratios.The total NPK nutrient content of the vegetative organs was leaf,lateral root and petiole,and the total nutrient content was N>K>P.It is concluded that the treatment of N3P2K2 is beneficial to increase the total nitrogen content of rubber somatic embryo seedling;the treatment of N1P2K2 is beneficial to increase total phosphorus and total potassium content.(10)The total nutrient accumulations of vegetative organs and plants of rubber sapling under different fertilization rates increased first and then decreased with the increase of fertilization amount,the nutrient accumulation of fertilization treatments was higher than the non-fertilizer treatment,the organs with the highest nutrient accumulation were stem,and the order is N>K>P.(11)The vegetative organs and total NPK fertilizer utilization rate decreased with the increase of fertilizer application rate,the utilization rate of NPK fertilizer was the highest under low fertilization treatment,and the fertilizer utilization rate of stem was the highest.