不同采收时间对白及块茎重及品质的影响

Study of the Effect of Different Harvesting Times on the Weight of Tuber and Quality of Bletilla striata

目的:确定白及块茎的合适采收时间,为白及的种植提供技术支撑。方法:以白及采收期内不同采收时间的白及块茎为研究对象,分析白及块茎重、折干率和块茎中的白及多糖、总酚、微量元素及重金属含量,分析其随不同采收时间变化规律。结果:采收时间对白及块茎重、折干率没有显著影响;不同采收时间白及块茎中微量元素含量均以Fe含量最高,块茎中微量元素总量随采收时间的延长而升高,以10月份总量最高;As、Cr及Cu随采收时间的延长其含量总体升高,Cd和Pb随采收时间的延长出现峰值后降低;除8月份白及块茎中Cd超标外,其他样品均没有超标,重金属总量以10月份最高;随着采收时间的延长,白及多糖含量逐渐降低,总酚含量逐渐升高。结论:综合白及块茎中主要有效成分、微量元素的含量,并考虑重金属的安全性,白及块茎的较佳采收时间为9月中旬。

Objective:To determine the appropriate harvesting time of Bletilla striata tuber,so as to provide technical support for planting of Bletilla striata.Methods:Taking Bletilla striata tuber with different harvesting time during the harvesting period as the research object,the weight,drying rate and contents of polysaccharide,total phenol,trace elements and heavy metals in Bletilla striata were analyzed.The variation law of them with different harvesting time was studied.Results:Harvesting time had no significant effect on Bletilla striata tuber weight and drying rate.Fe content was the highest in Bletilla striata tuber at different harvesting times.The total amount of trace elements in tuber increased with the extension of harvesting time,and the total amount was the highest in October.The contents of As,Cr and Cu increased with the extension of harvesting time,while the contents of Cd and Pb decreased with the extension of harvesting time.Except for the Cd in Bletilla striata tuber in August,the others did not exceed the standard,and the total amount of heavy metals was the highest in October;As the harvesting time extension,the content of polysaccharides in Bletilla striata tuber gradually decreased and the total phenolic content gradually increased.Conclusion:Considering the content of main active components and trace elements in Bletilla striata tuber and the safety of heavy metals,the best time to harvest Bletilla striata tuber is mid-September.