Effect Of Nitrogen Potassium Fertilizer On Yield And Quality Of Ramie(Boehmeria Nivea (L.) Gaud)

Ramie (Boehmeria nivea (L.) Gaud) is an important bast fiber crops in the world, occupies an important position in the national economy. The Yangtze River is China’s ramie focus areas, but also the further development of the ramie production in key areas. The ramie wide distribution area, yield potential, but due to the special ecological conditions, and high-yield, high-quality cultivation technology research and application lag, making ramie of the Yangtze River Basin to improve the yield and quality has been severely constrained. Test for the special ecological environment of the middle reaches of the Yangtze River region of N, P, K different fertilizer combinations of test factor, phosphate fertilizer as base fertilizer, nitrogen, potash quarterly component fertilization designed to study the various test factors of the "China-limonene on the4thyield, fiber quality, photosynthesis, and SPAD value. Seeking seed supporting good law for the middle reaches of the Yangtze River region, to achieve the purpose of output, income, and increased efficiency. The results show that:1. To improve the yield of ramie in different seasons, we should first apply high level of nitrogen (N4,420kg/hm2) and then medium level (N2,300kg/hm2), however the amount potassium should be increased gradually. Low level of nitrogen and potassium(N1,240kg/hm2、K1,120kg/hm2) poses negative effects on the yield. The nitrogen and potassium are not isolated but interact with each other considerably. So the use of nitrogen and potassium should be considered together. High level of potassium along with high level of nitrogen increases ramie yield. Ramie in the first season needs high level of nitrogen. Ramie in the second and third season need medium to low concentration of potassium (K2,180kg/hm2to K1) to decrease the amount of pectin. Low level of potassium increases the yield in the third season. Potassium is the major factor affecting the yield and influences the effect of nitrogen. Low level of potassium inhibits tillers in the first season. Nitrogen has little thing to do with the height of ramie when the second season of ramie is mature. However ramie in the third season needs more nitrogen because it enters the process of reproductive growth. So the application of nitrogen increases plant height and thereby increases the yield of seeds. 2. The interaction between nitrogen and potassium significantly affects the fiber quality. Medium level of nitrogen plays a major part in the increase of quality. The effect of potassium on the fiber quality has no regular pattern because it has been concealed by the interaction.3. High nitrogen and high potassium (K4,300kg/hm2) can not improve net photosynthetic rate of ramie, the application of potash and the interaction between nitrogen and potassium affect the net photosynthetic rate more significantly of the third season of ramie than the first and second season. Nitrogen levels only play a prominent role on the net photosynthetic rate in the reproductive growth period of the third season. ramie chlorophyll content increased with the increase of nitrogen content, but chlorophyll content decreased with the increase of nitrogen application when the third season entered the reproductive growth period. SPAD value was higher when Potassium was less, but in the harvest of third season, the SPAD values increased with the increase demand of potassium due to vigorous growth.4. High nitrogen and potassium promote the increase of the effective and total number of trees of the first season of ramie. High applied potassium fertilization and nitrogen was still needed but gradually reduced in the second season of ramie. The interaction between nitrogen and potassium was significant in the third season of ramie. The third season was near the reproductive growth, so the amount of nitrogen fertilizer should be reduced and we need to avoid the application of high-potash fertilizer when high nitrogen was used.