黄土高原一年生饲草作物产量与水分利用效率

Dry Matter and Water Use Efficiency of Annual Forage Crops in the Loess Plateau

一年生饲草作物是补充黄土高原地区冬春季家畜饲草供应的重要来源,而水分利用效率是评价饲草作物适应区域气候环境的重要表征。采用大田试验研究了甘肃陇东黄土高原雨养农业区9种春播一年生饲草作物〔玉米(Zea mays)、苏丹草(Sorghum sudanense)、大豆(Glycine max)、谷子(Setaria italica)、糜子(Panicum miliaceum)、箭筈豌豆(Vicia sativa)、豌豆(Pisum sativum)、燕麦(Avena sativa)和春小麦(Triticum aestivum)〕的饲草干物质产量土壤水分亏缺值和水分利用效率。结果表明:除苏丹草外,其余8种饲草作物的土壤水分亏缺值均呈现"V"型。出苗后6周,春小麦的水分利用效率最高;出苗后15周,玉米的水分利用效率高于其他饲草作物,而谷子和糜子的水分利用效率变幅比其他饲草作物小。在春播条件下,9种一年生饲草作物中,可优先选择玉米、春小麦、谷子和糜子。

Annual forage crops are important feeding sources in early spring and winter seasons in areas of the Loess Plateau,with water use efficiency being an important indication of crop adaptability to local climate environment. In a rainfed area of eastern Gansu,dry matter,soil water deficit and water use efficiency of annual forage crops were determined. Annual forage crops were maize（ Zea mays）,Sudan grass（ Sorghum sudanense）,soybean（ Glycine max）,small millet（ Setaria italica）,millet（ Panicum miliaceum）,common vetch（ Vicia sativa）,pea（ Glycine max）,oat（ Avena sativa） and spring wheat（ Triticum aestivum）. The results showed that soil water deficit of annual forage crops presented a ‘V＇curve,with the exception of Sudan grass; water use efficiency of spring wheat was higher than other crops at 6 weeks after emergence,whereas maize was the most efficient at 15 weeks after emergence. Variable amplitude of water use efficiency in millet and small millet was low. The crops of maize,spring wheat,small millet and millet were optimum under spring-sown condition in the Loess Plateau.