Research On Effect Of Soil Test And Formulated Fertilization For Ramie

Based on the positioning sites of ramie in Liuyang, this study selected "3414" recommend by FAO as experimental methods. The field experiment was performed to study the effects of different formula fertilization by soil testing on the fiber yield and economic benefits of Zhongzhu-1. The main results are as follows:Different formula fertilizations have significant impact on fiber yield and economic benefits of ramie. Compared with the CK, the fiber yield of ramie was maximum appeared in N2P2K2 treatments that increased by 47.60%. The best fertilizer efficiency of first crop, second crop, third crop and annual yield in fertilizer plots increased 1076.2 yuan/hm2, 1701.3 yuan/hm2,1372.5 yuan/hm2 and 3878.5 yuan/hm2 respectively.The fertilizer interaction effect in NPK treatment was the most significantly, the next were NK treatment and NP treatment. In this study, the dependent rate on soil fertility was 67.75% and higher than the dependent rate on fertilizer. The testing grounds soil is rich, the soil total nitrogen contents was at middle level in first crop and low level in second and third crops. The available phosphorus and potassium were at high level in the whole growing period. The result showed that nitrogen affected fiber yield very much, potassium less, and phosphorus the least.The nitrogen and potassium fertilizer had more significant effects on fiber yield and its constitution of ramie than phosphorus fertilizer. The fertilizer affected bark yield and effective plant very much, the effect on stem diameter and bark thickness were less, and plant height the least. The bark yield and effective plant has a large direct positive effect on fiber yield of ramie, the plant height has a large negative effects on fiber yield of the first and second crops. The stem diameter and bark thickness had little effect on fiber yield. Path coefficient analysis indicated that the fiber yield is composed of plant height, stem diameter, bark thickness, bark yield and effective plant.There was a difference of absorption of NPK ratio between different seasons and different fertilizer levels. In addition to the second crop affected by drought, the trend of dynamic changes of N, P and K accumulation amount was the same as the trend of dry matter accumulation amount in ramie. The amount of N, P and K uptake were third crop> first crop> second crop and NPK treatment＞ CK in producing the same amount of fiber. The allocation amounts of N, P and K in the vegetative organs were more in leaves, less in barks and bones. The N and P contents were highest in leaves at later growth stage, but the K contents were highest in barks.When the ratio of N and P was at a high level, to improve the ratio of P and K could increase the soil pH. But the high ratio of N and K and high yield increased the consumption of soil organic matter. The soil total potassium, total phosphorus and available phosphorus content increased after applying N, P and K fertilizers.The sequence of fertilization effect is N> K> P, the phosphorus fertilizer has insignificant effects on fiber yield of ramie. The agronomic efficiency of nitrogen and phosphorus fertilizer was in line with the law of diminishing marginal returns, but the agronomic efficiency of potassium fertilizer increased, and then decreased. In this study, the second NPK level can not only improve the yield but also reduce the burden on the ecological environment.There were 8 "N, P single factor representative model fertilizer response equations", 3 "ternary quadratic representative model fertilizer response equations" and 5 "non-representative model fertilizer response equations" established by DPS data-processing software. According to the single factor fertilizer response equations, the fertilizer proportion of N, P and K were 4.47:1:1.10 for the annual optimal yield and 4.25:1:4.83 for the annual highest yield. According to the ternary quadratic fertilizer response equations, the fertilizer proportion of N, P and K were 1:0.01:1.34 for the annual optimal yield and 4.98:1:5.10 for the annual highest yield.From what has been discussed above, different formula fertilizations have significant impact on fiber yield and economic benefits of ramie. Proper fertilization is the basis of improve crop yields and economic benefit, and also is the methods for improving fertilizer efficiency, reducing the wasting of fertilizer and protecting the environment of agricultural production. The best fertilizer of N, P and K was 336.51 kg/hm2,4.12kg/hm2 and 450.00 kg/hm2 respectively in this test. The expected annual yield was 4170.75 kg/hm2 and economic benefits was 22611.55 yuan/hm2.