Abstract:

To find the optimal utilization method of Pennisrtum purpureumxp typhoidevm‘Reyan No.4’with high forage quality and yield in Henan yellow river beach, a series of cutting combination trials (every 30 days, 40 days and 60 days cutting with 15~20 cm post-cutting stubble heights, respectively) were conducted to study the effects of different cutting frequencies on growth character devlopment, production performances and nutrition levels to provide stable and good forage for local herbivore develpment. The result showed that cutting had significant effects on the growth and production of Pennisrtum purpureumxp typhoidevm ‘Reyan No.4’, which decreased stem length and lodging rate, and increased stem thickness and tiller number. Frequent cutting led to the decrease of stem to leaf ratio(S/L ratio), leaf area index(LAI), and growing rates, following with lower forage productivity; suitable cutting increased fresh to dry ratio (F/D ratio), tiller numbers of individual plant and growing rates, which was good for forage productivity. Cutting had great effects on the contents of crude protein(CP) and crude fiber(CF) of Pennisrtum purpureumxp typhoidevm ‘Reyan No.4’, but had no effects on the contents of ether extract(EE), ash(A) and nitrogen-free extract(NFE). High frequency of cuttings increased the content of protein and decreased the content of crude fiber. When cutting frequency was every 30 days and 40 days, the content of crude protein enhanced 5.47%(P<0.05)and 2.80%, the content of crude fiber decreased 6.67%(P<0.05) and 5.54%(P<0.05)compared with only cutting once annually. When cutting frequency was every 60 days, forage nutrients were similar to cutting once. Generally, optimal cutting methods was 60-day cutting interval with 15~20 cm post-cutting stubble height, which annual forage yield was up to 29.83 t DM·hm^-2 and content of crude protein of forage reached 13.01%.

Key words: Yellow river beach, Pennisrtum purpureumxp typhoidevm ‘Reyan No.4’, Cutting, Production

摘要：

为了找到热研4号王草（Pennisrtum purpureumxp typhoidevm ‘Reyan No.4’）在河南省黄河滩区营养和产量俱佳的刈割利用方式，从苗高80 cm开始，在留茬15~20 cm的情况下，采用每隔30 d、40 d、60 d和全年1次性的刈割方式，研究不同刈割方式对王草生长、产量和营养水平的影响，为当地草食家畜的发展提供优质且稳定的饲草。研究表明：刈割会限制茎长，增加茎粗，有利于植株的分蘖及降低倒伏率；过频刈割会降低茎叶比（S/L ratio），叶面积指数（LAI）和生长速度，不利于饲草生产；适度的刈割有利于提高鲜干比（F/D ratio）、单株分蘖数和生长速度，有利于牧草的高产。另外，刈割次数对热研4号王草粗蛋白质和粗纤维含量有显著影响，而对粗脂肪、粗灰分和无氮浸出物含量影响不显著，多次刈割会提高粗蛋白质含量、降低粗纤维含量，每隔30 d与40 d刈割1次与1年仅割1次相比，粗蛋白质含量分别提高5.47%（P<0.05）和2.80%，粗纤维含量分别降低6.67%（P<0.05）和5.54%（P<0.05），而每隔60 d刈割1次和1年仅割1次相比，饲草营养没有显著差异。综合评价结果表明：每隔60 d刈割1次，一年刈割2次，留茬15~20 cm，牧草生长良好，粗蛋白质含量可达到13.01%，全年产草量达到29.83 t DM·hm^-2，均达到理想水平。

关键词: 黄河滩区, 热研4号王草, 刈割, 生产