Abstract:

To provide technical basis for the rational utilization of white clover in tea plantation and seek the best return method,the decomposition characteristics of white clover under different returning methods and the effects on the yield and quality of tea were studied. Using nylon mesh bags,the decomposition characteristics and nutrients releasing law of white clover under soil coverage treatment(T1),straw mulching treatment(T2)and natural death treatment(T3)were researched,and it was set plot experiment in tea plantation to analyse the affects of tea yield and quality. The results showed that:the cumulative decomposition rate was 73.4%-89.8% after 160 days under the three returning methods of tea plantation intercropping white clover,and the speed was T1>T2>T3. T1 and T2 showed the characteristics of fast first and then slow. T1 treatment was the fast stage from 0 to 10 days,and the slow stage from 10 to 160 days. T2 treatment was the fast stage from 0 to 20 days,and the slow stage from 20 to 160 days,however,the decomposition time of T3 treatment was delayed,and the decomposition was started from the 40th day,and kept fast in the later period;the release rate and amount of nutrients showed as T1>T2 and T3,nutrients releasing of N,P,K,C were more complete. The releasing of K was the most complete,followed by N and P,the C was the least. After 160 days,the releasing rates of K,N,P and C were 95.1%-99.7%,75.3%-95.6%,86.4%-93.9% and 69.5%-91.6%;the yields of summer and autumn tea were increased by 9.4%-27.0% and 5.9%-28.2% than CK,and the tea quality was improved. The water extract and amino acid of summer and autumn tea were increased by 0.7%-4.2% and 2.0%-17.0%,and the phenol/ammonia of summer tea was decreased,the decreasing rate was from 0.9% to 12.0%. Therefore,considering the factors of decomposition rate,nutrient releasing,yield and quality of tea,the returning method of soil coverage(T1 treatment)is fist recommended udder tea plantation intercropping white clover in tea plantation.

Key words: White clover, Returning methods, Decomposition characteristics, Tea, Yield, Quality