Studies On The Ramie Root Rhizosphere Environment And Its Effects On Fiber Yield And Quality

Ramie is an important special fiber industrial crop in china, which is planted widely. As to the culture of ramie, it's very important to study the ramie root rhizosphere environment. The correlations between the ramie root rhizosphere environment factors and the fiber yield traits and quality characters were studied by ramie varieties test (Wangcheng) and application fertilizer test (Yuanjiang), which applies reference in order to direct practical production. Main research results as follows:1. The comparison between the rhizosphere soils and bulk soils(Wangcheng)concluded that the contents of N, P, K, soil organic matter, urease, acid phosphate, bacteria, actinomycetes, fungi, water content, excepting P, were higher in the rhizosphere soils than those in the bulk soils(p<0.05). And there were significantly differences on the pH between the rhizosphere soils and bulk soils. The results also showed that there were mang significant positive correlations among soil environment factors in bulk soils.2. The main factors that could affect the ramie root rhizosphere environment were varieties, seasons, fertilization measures. First, there was a difference among genotype on the content of total nitrogen, total phosphorus, total potassium, and bacteria number, pH in the rhizosphere soils. Second, the content of available N declined gradually with the passing of harvest season and the content of available K was highest in the rhizosphere soils at the second season both in Wangcheng and in Yuanjiang. The content of available P was accumulated in the second season in Wangcheng, yet being accumulated gradually with the passing of harvesting season in Yunjiang. But the content of soil organic matter declined gradually in Wangcheng and was accumulated in the second season in Yuanjiang. Last, there is significant positive correlation between the content of available N and the application rate of phosphoric fertilize(rr=0.420^*), and the effect of N, P, and K fertilization on the contents of available nutrient in ramie harvesting time were not obvious. Besides, there were good correlations among the contents of the seasoning available nutrients, good correlations between the contents of the seasoning available nutrients and those in the previous season.3. In the ramie varieties test, under the same soil fertility and fertilizer supplying level, the differences among genotype on the contents of total nitrogen, total phosphorus, total potassium showed the diversities on the absorption and utilization of N, P, and K nutrients by ramie plant,which could direct the fertilizer application of different ramie varieties The correlation analysis showed that there was a highly significant negative correlation between plant height and total P(r=-0.702^**), a significant negative correlation between plant height and available P(r=-0.511^*), a significant positive correlation between harvest amount and total P(r=0.574^*), between plant height and total K(r=0.481^*), a significant negative correlation between fiber fineness and total P(r=-0.517^*), a highly significant negative correlation between filament strength and total K(r=-0.599^**).4. In the application fertilizer test of ramie, it was found that the amounts of commercial fertilizer, contents of the seasoning available nutrients, soil organic matter, pH and those in the previous season had some degree effect on the fiber yield traits and quality characters. In the first season, the main influencing factors were the amount of phosphate f fertilizer, contents of the seasoning available N, available P, available K, soil organic matter, and pH. In the second season, there significant correlations between fiber yield traits, quality characters.and the amount of potassium ertilizer, available K, available N, pH. While in the third season, the main influencing factors were the amount of nitrogenous fertilizer, available N, available P, soil organic matter, and pH. Then the differences of the influencing factors in three seasons could direct the fertilizer application of different sensons.5. There were many differences on the yield and the quality of ramie among three harvesting seasons between Wangcheng and Yuanjiang, the studies showed that there were significant differences on the contents of the seasoning available N, available P, available K, soil organic matter, and pH.