平茬对岩黄芪属植物生物学性状的影响

探讨了3种岩黄芪属植物平茬与未平茬植株的生物学性状.结果表明,平茬后3种岩黄芪属植物植株的多种性状与未平茬植株无显著差异，但平茬植株基部新生枝条数比未平茬植株增加1.91倍.平茬不仅复壮了植株个体，提高了产量，而且提高了家畜可食部分（叶+嫩茎）的比例.平茬岩黄芪属植株5～8月生物量中以叶和嫩茎为主，在9月，由于枝条木质化，家畜不可食部分迅速增加，平均不可食部分占总生物量的69.26％.而未平茬的岩黄芪属植株由于有上一年残留的枯死枝条，因而5～8月一直有老茎存在，9月份家畜不可食部分平均达到77.79％.岩黄芪属植物可在植物生长的第2年进行平茬，应在8月底以前进行收割.8月平茬处理3种岩黄芪灌丛的叶面积指数高于对照，散射光系数低于对照，说明在8月平茬处理植株的生长高于对照植株，生长更为繁茂.

Effects of cutting on biological characteristics of three Hedysarum species

The study with 3 species of Hedysarum showed that no significant difference was observed in many of their biological characteristics between treatments cutting and un-cutting, but the number of new branches sprouted from base stem was 1.91 times higher in treatment cutting than in un-cutting. Cutting could not only rejuvenate the plants, but also increase the yield and ratio of edible parts (leaves and tender stems). From May to August, the plants in treatment cutting had more leaves and tender stems but less old stems, and in September, their inedible part for livestock was 69.26% of the total biomass while that in treatment un-cutting was 77.79%. The appropriate period of cutting was by the end of August in the second year of Hedysarum growth. After cutting in this month, the leaf area index of 3 species Hedysarum was higher, while the dispersion light coefficient was lower, indicating that Hedysarum was more flourishing under cutting.