灌水定额分配对紫花苜蓿播种当年生长和干草产量的影响

Effects of irrigation quota on growth and yield of dripirrigated alfalfa in first growing year

通过滴灌条件下不同灌水定额分配比例对紫花苜蓿播种当年生长和干草产量的影响,确定最佳苜蓿灌水定额分配比例。在总灌水量相同的情况,设置3种灌水模式:(1)F1刈割前灌溉35%+刈割后灌溉65%;(2)F2刈割前灌溉50%+刈割后灌溉50%;(3)F3刈割前灌溉65%+刈割后灌溉35%。结果表明,第1年生紫花苜蓿第1茬刈割前株高为F3>F2>F1处理(P>0.05),叶茎比F1、F2显著大于F3处理(P<0.05),茎粗为F3>F2>F1处理(P>0.05),产量为F3>F2>F1处理(P<0.05)。第2茬刈割前苜蓿株高为F1>F2>F3处理(P<0.05),叶茎比为F3显著大于F1和F2处理(P<0.05),茎粗为F1>F2>F3处理(P>0.05),增长速率在分枝期F1显著大于F2和F3处理(P>0.05),现蕾期和初花期F1和F2显著大于F3(P>0.05),苜蓿产量为F1>F2>F3处理(P<0.05)。第1年紫花苜蓿的干草总产量为F1>F2>F3处理,F1处理最高,为10 472kg/hm2,比F2处理增产8%,比F3处理增产19%。综合分析苜蓿的各个性状指标,在新疆绿洲区滴灌条件下,第1年生紫花苜蓿每茬刈割前灌溉35%+刈割后灌溉65%(F1)有利于提高滴灌苜蓿干草产量。

In order to determine the best proportion of irrigation quota,the effects of different irrigation quota on the yield of alfalfa in first growing year under 3irrigation treatments（35% before mowing＋65% after mowing,F1;50% before mowing＋50% after mowing,F2;65% before mowing ＋ 35% after mowing,F3）were studied.The results showed that the plant height of alfalfa before the first cutting was F3〉F2〉F1（P〈0.05）,the leaf to stem ratio in F1 and F2treatments was significantly higher than F3（P〈0.05）,the stem diameter order was F1〉F2〉F3（P〈0.05）,the hay yield order was F3〉F2〉F1（P〈0.05）.The height before second cutting was F1〉F2〉F3（P〈0.05）,the leaf to stem ratio in F3 treatment was significantly higher than F1 and F2（P〈0.05）.The growth rate in F1 treatment was significantly higher than F2 and F3in branching period of（P〈0.05）,and those in F1 and F2treatments were significantly higher than F3 in squaring period and at initial flowering stage（P〈0.05）.The plant stem diameter order was F1〉F2〉F3（P〉0.05）,the yield order was F1〉F2〉F3（P〈0.05）.The total annual hay yield order was F1〉F2〉F3.The total annual highest hay yield obtained in F1 treatment and it reached 10 472kg/ha,8% higher than F2 and 19% higher than F3.After the comprehensive analysis,it showed that the best irrigation treatment was 35% before mowing and 65% after mowing in the oasis area of Xinjiang.