Study On Nutrient Distribution And Recommended Fertilization Technology Of Areca

Betel nut has extremely high economic benefits and is one of the main economic pillars of Hainan.However,the"predatory"business model is still used in the cultivation and production of betel nuts.The nutrients of betel nuts are not replenished,and even yellowing occurs,which severely limits the yield and quality of betel nuts.In order to guide the local farmers to use fertilizer scientifically and efficiently.Through the monitoring of nutrients in different organs of betel nut at different growth periods,combined with the betel nut biomass model to predict the dry matter accumulation model of main organs,the distribution and absorption laws of nutrients in different growth periods of betel nut were explored to determine the nutrient requirements of areca nut,and provide a certain theoretical basis for judging the nutrient demand characteristics of betel nut,to maximize the efficiency of fertilizer use in all aspects of crop nutrient supply.So as to achieve precise fertilization in production and improve the yield and quality of betel nuts.Secondly,by comparing normal and yellow betel nut plants,to explore the cause of betel nut yellowing from the perspective of nutritional deficiencies,and to increase the growth status of betel nut plants by adding nutrients,which provided a theoretical basis for the study of physiological yellow of areca.The theoretical results of this study are as follows:1 The soil in the four areas of Danzhou,Ding'an,Wanning and Qiongzhong in Hainan showed strong acidity as a whole.The contents of total P,effective P,exchanged Ca,Fe,Cu,Zn and Mn were all in abundance,organic matter,alkali hydrolyzed N,total K,available K,and exchanged Mg are at a medium level;The contents of total N and B are at the extremely deficient level.The demand for P,Ca,Mg,Fe,Cu,Zn elements in betel nut plants is mainly concentrated in the bud stage,the demand for N,K,B elements is concentrated in the bud stage and fruit stage,and the demand for Mn element is mainly concentrated in the flowering stage.2 Soil p H and nutrient content?total P,Ca,Mg,Cu?will show a downward trend as the yellowing of betel nut deepens.The total amount of Mn,Zn,Fe,K,Ca in leaves and veins of yellowed betel nut plants was significantly reduced,the total amount of Mn,Fe,P,Ca,N in interior leaf was significantly reduced,the total amount of Mn,B,Fe,Ca,Zn in flower bud was significantly reduced,the total amount of Mn,Fe,Zn,K,N in the fruit is significantly reduced,and the total amount of Mn,N,K,Fe,Zn in the fruit spur is significantly reduced.In general,the annual average total amount of each element of the whole plant,the total amount of N,Mn,K,and Cu elements of yellowed betel nut are significantly lower,and the difference in flower bud period is more obvious.Fertilization should be the most beneficial at this time.In order to reduce the difference between the yellowing group and the normal group,the amount of fertilization should be supplemented as follows:N 192.38g/plant,K 125.45g/plant,Mn 323.96mg/plant,Zn 109.35g/plant,Cu 106.86g/plant.3 The underground biomass of betel nut is mainly related to 0m stem diameter,the relevant model is RDW=0.5044×SD₀-8.3935,the coefficient of determination R² is0.2217.The stem biomass of betel nut is mainly related to plant height and 1m stem diameter,the related model is SDW=0.7274×SD₁+0.0396×PH-35.4844,the coefficient of determination R² is 0.7106.The leave biomass of betel nut is mainly related to the number of leave,1m stem diameter,the length of the stem nodes,and the related model is LDW=0.2806×LN+0.1556×SD₁-0.2163×IL-3.2661,the coefficient of determination R² is 0.4461.The flower biomass of betel nut is mainly related to the number of female flower,the thickness of the base,and the number of branches of grade 2,the relevant model is FDW=0.2860×FN+5.4493×BT+1.2026×BN₂-106.0291,the coefficient of determination R² is 0.6613.The fruit biomass of betel nut is mainly related to the number of fruit and the spreading length of lateral branch,the relevant model is Fr DW=3.0486×Fr N+4.1606×LL-87.3049,the coefficient of determination R² is 0.8401.The fruit and spur biomass of betel nut is mainly related to the number of fruit,the spreading length of lateral branch,and the length of main branch,the relevant model is Ft DW=3.5313×Fr N+4.7608×ML+3.6268×LL-183.9450,the coefficient of determination R² is 0.8900.4 Betel nut leaf number?LN?,1m stem diameter?SD₁?,plant height?PH?,stem height,number of node,average internode length?IL?=stem height/node number,average number of betel nuts per shuttle?Fr N?,The average main branch length?ML?per twig branch,the average lateral branch expansion length?LL?per twig branch.For the normal betel nut in the four areas of this experiment,the amount of elements to be supplemented within one year is:N?g?=4.03×LN+2.77×SD₁+2.96×PH+0.22×Fr N+0.30×ML+0.23×LL-3.10×IL-84.99;P?g?=0.43×LN+0.31×SD₁+0.39×PH+0.03×Fr N+0.04×ML+0.03×LL-0.33×IL-10.11;K?g?=1.50×LN+1.27×SD₁+2.40×PH+0.14×Fr N+0.19×ML+0.14×LL-1.15×IL-46.10;Ca?g?=1.92×LN+1.41×SD₁+1.90×PH+0.07×Fr N+0.10×ML+0.07×LL-1.48×IL-43.12;Mg?g?=0.47×LN+0.35×SD₁+0.49×PH+0.03×Fr N+0.04×ML+0.03×LL-0.36×IL-11.40?Fe?mg?=22.70×LN+34.94×SD₁+121.67×PH+1.57×Fr N+2.11×ML+1.61×LL-17.49×IL-1436.12;Mn?mg?=10.43×LN+6.69×SD₁+4.90×PH+0.25×Fr N+0.34×ML+0.26×LL-8.04×IL-178.28;Zn?mg?=3.09×LN+4.50×SD₁+15.19×PH+0.23×Fr N+0.30×ML+0.23×LL-2.38×IL-183.80;Cu?mg?=1.50×LN+1.49×SD₁+3.58×PH+0.10×Fr N+0.13×ML+0.10×LL-1.15×IL-54.46;B?mg?=2.94×LN+2.60×SD₁+5.31×PH+0.64×Fr N+0.86×ML+0.65×LL-2.26×IL-114.85?5 For the betel nuts in the yellowing group in the four regions of this experiment,in order to reduce the difference between the betel nut and the normal group,the appropriate amount of fertilizer should be supplemented as follows:N?g?=4.03×LN+2.77×SD₁+2.96×PH+0.22×Fr N+0.30×ML+0.23×LL-3.10×IL+107.39;K?g?=1.50×LN+1.27×SD₁+2.40×PH+0.14×Fr N+0.19×ML+0.14×LL-1.15×IL+79.35;Mn?mg?=10.43×LN+6.69×SD₁+4.90×PH+0.25×Fr N+0.34×ML+0.26×LL-8.04×IL+145.68;Zn?mg?=3.09×LN+4.50×SD₁+15.19×PH+0.23×Fr N+0.30×ML+0.23×LL-2.38×IL-74.45;Cu?mg?=1.50×LN+1.49×SD₁+3.58×PH+0.10×Fr N+0.13×ML+0.10×LL-1.15×IL+52.40;...