Effects Of Root Fertilizing With Nitrogen, Phosphorus And Potassium Fertilizers On Nut Yield And Quality Of Juglans Regia ‘Xinxin2’

Juglans regia ’Xinxin2’ is the main cultivar in walnut major producing area of South Xinjiang basin. However, due to lacking for a quantitative study of yield and quality effects of N, P and K root application, resulting in no evidence of fertilizing and soil nutrient management, it has become the main limiting factor for achieving high quality and yield of J. regia ’Xinxin2’ production garden. Therefore, J. regia ’Xinxin2’, Wushi, Aksu prefecture, Xinjiang planted was taken as the research object. With the methods of field trials and indoor analytical chemistry, using multiple linear stepwise regression analysis, nuts yield per plant and quality effect were quantitative analysis under medium soil nutrient conditions. Based on its effect relationship, fertilizer application amount parameter of N, P, and K was collated and stipulated through synthetic decision. The main results were as follows:The effect relationship of nuts yield per plant(G, kg) in N, P and K root fertilizing was ?log10G =0.9256+0.1822N-0.0757N2+0.6372K-1.2016K2. If the fertilizing amount of N fertilizer(pure N amount) was less than 2.4069 kg per tree and/or the fertilizing amount of K fertilizer(pure K2 O amount) was less than 0.5303 kg per tree, the fertilizer application amount had positive effect on nuts yield per plant of J. regia ’Xinxin2’; Otherwise it had negative effect.The nuts quality effect relationships in N, P and K root fertilizing were explained in the following subsection. Nuts single fruit weight(W, g): 10?log W =1.0250+0.1577P-0.1378P2. If the fertilizing amount of P fertilizer(pure P2O5 amount) was less than 1.1443 kg per tree, the fertilizer application amount had positive effect on nuts single fruit weight of J. regia ’Xinxin2’; Otherwise it had negative effect. Nuts Kernel rate(Y, g/g):10?log Y =-0.3082+0.0351N-0.0124N2+0.1009K-0.1767K2. If the fertilizing amount of N fertilizer(pure N amount) was less than 2.8418 kg per tree and/or the fertilizing amount of K fertilizer(pure K2 O amount) was less than 0.5713 kg per tree, the fertilizer application amount had positive effect on nuts kernel rate of J. regia ’Xinxin2’; Otherwise it had negative effect. Nuts crude fat content(E, g/g): 10?log E =-0.2201+0.2466K-0.3683K2-0.0083 N. N fertilizer(pure N amount) had negative effect on nuts crude fat content of J. regia ’Xinxin2’. If the fertilizing amount of K fertilizer(pure K2 O amount) was less than 0.7088 kg per tree, the fertilizer application amount had positive effect on nuts crude fat content of J. regia ’Xinxin2’; Otherwise it had negative effect.Nuts crude protein content(C, g/g): 10?log C =-0.8603+0.1222N×K. The interaction effect of N fertilizer and K fertilizer(N×K) had positive effect on nuts crude protein content of J. regia ’Xinxin2’.Under medium soil nutrient conditions, the fertilizer application amount(pure amount) parameter in N, P and K root fertilizing were explained in the following subsection. N was 1.4186 kg per plant. P2O5 was 0.5722 kg per plant. And K2 O was 0.3351 kg per plant.