因此，按照要求定向培育草原田鼠变种有助于进行研究。

Being able to create genetic variants of prairie voles to order would therefore be helpful to research.

定向培育阔叶树工业人工林是解决我国木材紧张局面的根本途径。

Oriented cultivation of hardwood industrial plantation was the fundamental way to resolve the tense situation of Chinas' timber.

结果表明：杉间材物理力学性质较天然林差。为杉木的定向培育。

The results show that the physical and mechanical properties of middle cutting wood of Cunninghamia lanceolata are inferior to those from natural forest.