富硒区茶树鲜叶中硒累积与土壤因子的相关性分析

Correlation Analysis Between Selenium Accumulation in Tea Leaves and Soil Factors in Selenium-rich Areas

茶树是富硒植物,饮用富硒茶是一种安全、有效的补硒途径之一。茶叶的硒含量受多种环境因素影响,但有关富硒茶区茶树硒积累特性及主要影响因子的研究还鲜有报道。以高硒茶区湖北恩施、陕西安康不同地点生产茶园成龄茶树和根际土壤为研究对象,结合土壤及植物样品全硒含量等多种指标,明确了根际土壤硒含量对茶树硒分布特性的影响,分析了富硒区土壤pH、硒含量等9个重要土壤特性相关因子的数值分布规律。通过对186组具有代表性的土壤样品和附生茶树新梢组织检测数据进行分组和整体相关性分析,证实了富硒区茶叶全硒含量与土壤硒含量之间存在极显著相关(相关系数r=0.59,P<0.01),揭示了茶叶全硒含量与土壤有机质含量、水解性氮、锌含量以及茶叶中硫、锌含量的显著相关,同时对安康和恩施地区的土壤和茶叶硒含量相关因素进行了深入分析。提出了茶叶硒含量对土壤有机质含量、硫含量、硒含量和锌含量的数学模型,模型拟合优度为0.5126,达极显著水平(P<0.01)。

Tea plant is a selenium-rich species and selenium-enriched tea products consumption is a safe and effective way to replenish selenium.Though the selenium content in fresh tea leaves can be affected by many environmental factors,selenium accumulation characteristics and main influencing factors of tea plants in selenium-rich areas were rarely reported.In this study,adult tea plants and rhizosphere soils from tea plantations in Enshi,Hubei and Ankang,Shaanxi were taken as research objects.Combined with various indicators such as total selenium content in soil and plant samples,the effect of selenium content in rhizosphere soil on the accumulation characteristics of selenium in tea plant was clarified.In addition,the importance of 9 important soil characteristics related factors such as soil pH and selenium content in selenium-rich areas were analyzed.Through grouping and overall correlation analysis of 186 representative soil samples and fresh tea samples,it was confirmed that there was a significant correlation between the total selenium contents in teas and soils(correlation coefficient r=0.59,P<0.01).Moreover,the total selenium content in tea was also significantly related to organic matter,hydrolysable nitrogen,zinc contents in soil and sulfur,zinc contents in shoots.The related factors of selenium content in soils and teas in Ankang and Enshi areas were also analyzed.A reliable mathematical model of selenium content in tea shoots on soil organic matter,sulfur,selenium and zinc contents was proposed.The goodness of fit was 0.5126,reaching a highly significant level(P<0.01).The above results were of great significance to improve the production technology of selenium-enriched fresh tea leaves in selenium-enriched tea areas and further revealed the selenium accumulation mechanism in tea plants.