用一般方法制得的叶脉标本极易损坏，使用聚乙烯醇埋制叶脉标本，成本低做果好，能达到长期保存的目的。将聚乙烯醇粉放入盛水的小烧杯中，再套在大烧杯中隔水加热至70－SOT，维持3Omin，即可制得10％－20％的胶液备用。在玻璃片上刷一层胶，将已除去叶肉、漂白染色后的叶脉标 The leaf vein specimens prepared by the general method are easily damaged, and the use of polyvinyl alcohol to inoculate the vein specimens is cost-effective and can achieve long-term preservation. The polyvinyl alcohol powder is placed in a small beaker filled with water, and then placed in a large beaker and heated to 70-SOT, maintained for 3Omin, and 10%-20% of the glue liquid can be prepared for use. Brush a layer of glue on the glass sheet, remove the leaf flesh, and bleach the stained vein markers