灌溉和施磷对紫花苜蓿干草产量及营养成分的影响

Effects of Irrigation and Phosphorus Supply Levels on Hay Yield and Quality of Alfalfa

采用完全随机裂区设计,灌溉[常规灌溉(330mm)、节水20%灌溉(264mm)和节水40%灌溉(198mm)]作为主处理,施磷(0,60,120,180kg/hm2)作为副处理,研究不同灌溉量和施磷量对紫花苜蓿干草产量、粗蛋白、粗脂肪、粗纤维和粗灰分的影响。结果表明,紫花苜蓿干草产量、粗蛋白、粗脂肪和粗灰分含量随灌溉量增加而增加,粗纤维含量随灌溉量增加而降低;紫花苜蓿干草产量、粗蛋白、粗脂肪和粗灰分含量随施磷量增加先增加后降低,粗纤维含量随施磷量增加先降低后增加。当施磷量达到60kg/hm2时,种植第3年的紫花苜蓿粗蛋白含量(23.87%)和粗脂肪含量(2.48%)均达到最大值;当施磷量达到120kg/hm2时,种植第3年的紫花苜蓿干草产量(19 114kg/hm2)达到最大值。

The study was conducted to establish an accurate irrigation and phosphorus （P） management sys- tem for alfalfa planting for the purpose of high hay yield and high contents of crude protein and crude fat by using a randomized complete block split plot design with irrigation levels （conventional irrigation. 330 ram, 20% water-saving irrigation, 264 mm and 40% water saving irrigation, 198 mm） and P fertility rates （0, 60, 120, 180 kg/hm2）） as the main plot and split-plot, respectively. The hay yield, the contents of crude pro- tein, the crude fat and the crude ash of alfalfa increased with the increase of irrigation levels, but the content of crude fiber decreased. The hay yield,the content of crude protein and the crude fat of alfalfa increased at first, and then decreased with increase of P supply rate. But the content of crude fiber of alfalfa decreased at first, and then increased with increase of P supply rate. When the P application rate was 60 kg/hm2, the content of crude protein （23.87%） and crude fat （2.48%） of alfalfa reached to the highest level. And the total hay yield （19 114 kg/hm2） of alfalfa reached the maximum as the P application rate reached to 120 kg/hm2