Only a few forest tree species can develop viable seed from unpollinated ovules.

只有少数林木可以从未授粉的胚珠发育成有活力的种子.

辞典例句

Many forest tree species have multiple archegonia which, after fertilization produce a number of proembryos.

许多林木树种都有颈卵器, 受精以后便产生许多原胚.

辞典例句

Is the create a shelter, fast growing forest tree species of choice for high - tech .

是国内营造防护林 、 速生丰产林首选的 高新技术 树种.

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