渝产叶用银杏种苗质量的分级标准

Study on the standard of quality grading for leaf-producing Ginkgo biloba seedlings in Chongqing

【目的】研究重庆地区叶用银杏种苗质量分级标准.【方法】收集了30个批次树龄两年的银杏种子苗,对株高、地径、分枝数、根长、一级侧根数、分枝率等指标进行测定,通过SPSS19.0软件对各指标数据进行相关性分析、K-均值聚类法分析、主成分分析,结合生产实际确定重庆地区叶用银杏种苗的质量分级标准.【结果】以株高、地径、分枝率、一级侧根、平均分枝数为分级指标将叶用银杏种苗分为3个等级标准:一级苗:株高≥70 cm,地径≥9.5 mm,分枝率≥70%;二级苗:株高60~70 cm,地径8.5~9.5 mm,分枝率35%~70%;三级苗:株高≥50 cm,地径≥7.5 mm,分枝率≥12%;且各级苗一级侧根≥15条,平均分枝数≥2枝.【结论】通过对分级种苗定植次年生长情况调查分析,及内酯和黄酮含量测定结果,结合实际情况,建议生产上使用一、二级苗,不满足三级标准则为不合格规定苗,不能作为种苗使用.

【Objective】The study aimed to study the criteria on quality evaluating and grading for leaf-producing Ginkgo biloba seedlings.【Method】Two-year-old seedlings of G.biloba,which were collected in three times from different production areas in Chongqing,were employed as testing materials.The plant height,ground diameter,branch number,root length,fibrous root number and branching ratio of the seedings were measured,followed by the analyses such as Correlation,K-means cluster and Principal Component Analysis with SPSS19.0 software for the purpose of building grading standards.【Result】With plant height,ground diameter,branching rate,fibrous roots and average branches as the main grading indicators,the seedlings could be classified into three grades.The seedlings of each grade should meet the requirements as following:for the first-class seedings,plant height≥70 cm,ground diameter≥9.5 mm,branching rate≥5%;for the second class:plant height 60~70 cm,ground diameter 8.5~9.5 mm,and branching rate 35%~70%;for the third-class seedings:plant height≥50 cm,ground diameter≥7.5 mm,and branching rate≥12%;and for each class of seedings,fibrous roots≥15,average branch number≥2.【Conclusion】Based on the investigation on the each-class seeding's growth next year,it was suggested that the standard production of Ginkgo folium should use the first-and the second-class seedlings,and other seedings that were selected against according to the three-grade standards should not be used in the production.