Abstract:

To explore the effect of harvest on the forages root traits in Semi-Arid Region, indoor and field experiment were conducted to test root characteristics of Poa pratensis, Trifolium repens and Vicia villosa. The results showed that cutting can reduce the root depth, root length and root surface area. The root depth, root length and root surface area of P. pratensis at 3 cm stubble height were decreased by 43.91%, 51.85% and 25.52% compared to the control, respectively. At 3 cm stubble height, the root depth, root length and root surface area of T. repens decreased by 27.27%, 47.04% and 27.35% compared with the control, respectively. The root depth, root length and root surface area of V. villosa at 3 cm stubble height were decreased by 20.34%, 39.80% and 40.39% compared with the control, respectively. P. pratensis in field conditions showed the minimum root length density at 9 cm stubble height and T. repens showed the minimum root length density at 3 cm stubble height in field conditions, while V. villosa showed the minimum root length density at 6 cm height in field conditions. The research provided very important reference values for the choice of stubble height of cutting forages in semi-arid region.

Key words: Forages, Clipping, Root characteristics, Loess hilly region

摘要：

为探索半干旱区刈割对牧草根系特征的影响,本研究选用早熟禾(Poa pratensis L.)、白三叶(Trifolium repens L.)、毛苕子(Vicia villosa)为试验材料,采用室内和野外相结合的方法,研究了牧草根系特征对刈割的响应。结果表明:刈割可降低牧草根深、根长及根表面积。在刈割留茬3 cm高度时,早熟禾根深、根长及根表面积较对照分别降低43.91%,51.85%,25.52%;白三叶根深、根长及根表面积较对照分别降低27.27%,47.04%,27.35%;毛苕子根深、根长及根表面积较对照分别降低20.34%,39.80%,40.39%。野外早熟禾刈割留茬9 cm时根长密度最小,白三叶在刈割留茬3 cm时根长密度最小,毛苕子刈割留茬6 cm时根长密度最小。该研究对半干旱区牧草刈割留茬高度选择具有参考价值。

关键词: 牧草, 刈割, 根系特性, 黄土丘陵区