Effects Of Seaweed Extract On Phosphorus In Calcareous Soil And Rape Quality

Soil incubation experiment and rape pot experiment in greenhouse were carried out to study the changes of inorganic-P fractions in calcareous soil after application of seaweed extract. Extraction of inorganic-P fractions adopted the Jiang-Gu method. The effects of seaweed extract on biomass and quality of rape were also studied. The aim is to find the new way of enhancing phosphorus use efficiency in calcareous soil, improving nourishment condition of phosphorus and the yield and quality of crop. The results in this experiment showed as follows:Two kinds of seaweed extract can both increase the content of Ca₂-P, Ca₈-P, Al-P, Ca₁₀-P and totoal inorganic-P in soil under the condition of incubation. The content of Fe-P is decreased in the early stage of incubation. There is no influence to O-P. Norway's seaweed extract increased the content of Ca₂-P, Al-P and Ca₁₀-P obviously, the domestic seaweed extract increased the content of Ca₂-P,Ca₈-P, Al-P and Ca₁₀-P.The direct pot experiment and pot experiment after incubation were adopted. The results of two kinds of pot experiment all showed that percentage of Ca₂-P and Al-Pcan be increasedWhether in the condition of incubation or planting, the content of available P can be increased.Basal application and root dripping into seaweed extract solution are practiced in this paper. The effect of dripping is better than basal application in increasing the biomass of rape.Both the two kinds of seaweed extract can improve the quality of vegetable. They can increase the content of Vitamin C and dissolved sugar, while not increase the nitrate content.The influence of seaweed extract is greater to micro-nutrients than to macro-nutrients such as N, P and K. It improves the nutritional condition of rape apparently. It can increase Ca, Fe, Cu and Zn content and decrease Mg content in the rape. There was no influence to Mn content.