Effects of Fertilization on Selenium Content,Nutrient and Quality of Tea in Se-enriched Tea Garden
In order to provide efficient, high quality and safe fertilization to se-enriched tea producing areas, this paper studied the effects of applying organic fertilizer combined with phosphorus and potassium fertilizer(O1-O6), urea combined with phosphorus and potassium fertilizer(UI-U6); single application of organic fertilizer(O7, O8), and urea(U7, U8) on tea selenium content, nutrient and quality in se-enriched garden by field experiment. The results showed that the organic selenium content in spring and summer tea leaves were increased obviously by different fertilization, and the content of organic selenium in spring tea leaves was higher than that of summer tea leaves. The content of organic selenium was high by treatment of organic fertilizer application and improvement in tea leaves of both seasons was the most obvious in O6 treatment, and the contents were 0.158 mg/kg and 0.116 mg/kg, respectively, which were increased by 62.12% and 67.32% compared with that by conventional fertilization. The overall performance of nitrogen, phosphorus, potassium content was spring tea>summer tea, nitrogen, phosphorus, potassium contents in spring tea were the highest in O6 treatment, increased by 22.34%, 59.18% and 17.36% compared with that of the conventional fertilization, respectively. Spring tea quality was improved obviously by combined application of organic fertilizer; and summer tea quality was improved obviously by different fertilization treatments. The overall performance of tea phenol ammonia ratio was spring tea<summer tea, spring tea phenol ammonia ratio was the least in O6 treatment, reduced by 15.60% compared with that by conventional fertilization. Regression analysis showed that application of phosphate fertilizer in spring had significant effect on spring tea organic selenium content, application of nitrogen fertilizer in spring and summer had significant effect on summer tea organic selenium content.