肉桂酸降解真菌的筛选及其降解液对黄瓜种子发芽的影响

利用富集驯化培养、稀释涂布的方法，从连作黄瓜根际土壤中分离得到1株能降解肉桂酸的真菌2-4。该菌能够在以肉桂酸为唯一碳源的无机盐培养基上生长；经形态学、生理生化及分子等分类方法鉴定其为黑曲霉（Aspergillus niger）。该菌不同培养时间的肉桂酸降解液对黄瓜种子发芽试验表明，该菌可有效降解肉桂酸，从而缓解对黄瓜发芽的抑制作用，72 h降解液处理的种子发芽率、发芽指数和活力指数可分别达到对照的100%、92.06%和91.49%；胚根长、根表面积和根尖数达到对照的84.19%、87.55%和82.64%，而胚轴长、鲜质量差异不显著。

Screening and Identification of Cinnamic Acid-degrading Fungis and the Effect of Degradation Liquid on the Cucumber Germination

A fungi which is able to degrade cinnamic acid efficiently was isolated from cucumber rhizosphere soil by using enrichment and dilution separation methods. This strain could use cinnamic acid as the sole carbon source and was identified as Aspergillus niger by the morphological，biochemical characteristics and molecule analysis. Seed germination treated with degradation liquid of different time indicated that，this fungi could efficiently degrade cinnamic acid and alleviate the inhibition of cinnamic acid on cucumber germination. Seed germination rate，germination index and vigor index could separately reach 100%，92.06% and 91.49% compared with the controls in treatment with degradation liquid of 72 h. Radicle length，radicle area and root tip number also reached 84.19%，87.55% and 82.64%，hypocotyl length and fresh weight is not significant compared with the control.