Studies On The Nutrition Management In Glycyrrhiza Uralensis Fisch Cultivation

Glycyrrhiza uralensis Fisch is one of the most important medicinal plants in northern China and it also possesses significant value in ecological protection. The area of wild G. uralensis resources has decreased by 50 percent in the last 50 years. The crisis of wild resources has become more and more serious. Therefore, the systematic studies on nutrition management in G. uralensis cultivation can establish scientific and reasonable cultivating measure, improve the yield and quality of G. uralensis medicinal materials and protect the wild resources. At the same time, the achievement can provide scientific foundation for standardization cultivation of G. uralensis. On the basis of field investigation, potted experiment, field fertilization experiment and chemical analysis in laboratory, systematic studies were carried out on the soil chemical and physical characteristics in natural distributive area of G uralensis, nutrition characteristics of wild G uralensis, nitrogen nutrition characteristics, nitrogen phosphorus potassium nutrition characteristics, trace element nutrition characteristics and field fertilization strategy of cultivating G uralensis. The investigation plots covered 30 counties from Buerjin County in Xinjiang Weiwuer Autonomous Region to Qiqihaer City in Jilin Province. Two different field experimental districts located in Hangjin County and Chifeng City of inner Mongolia Autonomous Region and one year old seedling and one and two year old seedlings were selected as experimental materials in potted experiment. The main results are as follows:G uralensis mainly grows on sandy loam soil and the soil pH-value is 8.89.its changing scope from 7.59 to 10.10. Comparing to other places in the soil, the concentrations of nitrogen, phosphorus and potassium are lower, calcium carbonate, cupper, boron and molybdenum are higher, and iron, manganese and zinc are comparatively lower. The concentrations of heavy metal elements are within the limit. The natural distributive area of G. uralensis can be divided into 6 different soil sub-regions. The soil texture difference among sub-regions reaches significant level; the difference of phosphorus, cobalt, nickel and chromium in different sub-regions reaches most significant level and the difference of soil organic substance, nitrogen and potassium concentration is notsignificant.The distribution of nitrogen, phosphorus and potassium in different organs of wild G uralensis is same, the discipline is: concentration in leaf > in stem > in root. But the distribution of the trace element as manganese, zinc, copper and boron is contrary to the former; the distribution of other trace elements is also different. The concentration of nitrogen, phosphorus and potassium in G. uralensis leaf is higher than those in the single cotyledon plant leaf and the content of iron is also relative high and the contents of other trace elements are common. The contents difference of phosphorus, iron, molybdenum and magnesium in G. uralensis leaf and of glycyrrhizinic acid in G uralensis root in different soil sub-regions reach most significant level, the difference of boron content reaches significant level. The relativity between the soil available nutrient content and G uralensis leaf nutrient content and glycyrrhizinic acid content is not obvious. Among the entire nutrients in the G uralensis leaf, boron is the only element obviously related to glycyrrhizinic acid content, the regressive equation could be simulated between boron and glycyrrhizinic acid content.In nitrogen experiment, before the dosage of nitrogen fertilization reaches 1.2 g/pot, increasing the dosage of nitrogen fertilization accelerates the growth and physiological indicator. When the dosage reaches 1.2 g/pot, almost all indicators are highest, when the dosage exceeds 1.2 g/pot, all the indicators decline. The net photosynthesis rate of G uralensis has significant positive liner relationship with biomass and yield. The nitrogen, phosphorus and potassium contents in G uralensis leaf have liner relativity with...