论文部分内容阅读
近年来,杨树栽培面积日益扩大,杨树优良品种也不断涌现。但是,在杨树栽培过程中,杨树良种的退化现象日趋严重。如何保持杨树良种的优良性
In recent years, poplar cultivation area is expanding day by day, poplar fine varieties also continue to emerge. However, degeneration of poplar seeds is becoming more and more serious during poplar cultivation. How to maintain the goodness of poplar varieties