刈割对齐齐哈尔地区紫花苜蓿种子产量的影响

Effects of cutting on alfalfa seed yield in Qiqihar area

为了探究刈割对紫花苜蓿种子产量的影响,试验采用随机区组方法,以3年生的龙牧801苜蓿种子田为研究对象,分别于5月23日、5月31日、6月7日、6月14日进行刈割,每次刈割采用两种留茬高度,分别为6 cm和10 cm,并以不刈割作为对照。研究不同刈割时间和留茬高度对龙牧801苜蓿种子产量及其构成因子(每平方米生殖枝数、结荚花序数/生殖枝、荚果数/结荚花序、种子/荚果数)的影响。结果表明:6月7日刈割留茬高度10 cm处理的种子产量及结荚花序数/生殖枝、荚果数/结荚花序、种子数/荚果均显著高于对照(P<0.05)。各产量构成因子与种子产量均呈正相关,相关程度由大到小依次为荚果数/结荚花序>种子数/荚果>结荚花序数/生殖枝>每平方米生殖枝数。种子产量与各产量构成因子的逐步回归方程为:Y=17.360+4.961X_(3)(Y为种子产量,X_(3)为荚果数/结荚花序,R^(2)=0.4536,F=18.26^(**))。说明在黑龙江省齐齐哈尔地区通过刈割处理能够增加紫花苜蓿种子产量,结荚花序上的荚果数是影响种子产量的最重要因子。

In order to explore the effect of cutting on alfalfa seed yield, random block method was adopted in this experiment. Three-year-old Longmu 801 alfalfa seed field was taken as the research object. Cutting was respectively carried out on May 23, May 31, June 7 and June 14, respectively. Two stubble heights(6 cm and 10 cm) were used for each mowing, and no cutting was used as the control. The effects of different mowing time and stubble height on seed yield and component factors(number of reproductive branches per square metre, pod flowers number/reproductive branches, pod number/pod inflorescence, and seed number/pod) of Longmu 801 alfalfa were studied. The results showed that the seed yield, pod flower number/reproductive branches, pod number/pod inflorescence, seed number/pod under cutting treatment on June 7 with stubble height 10 cm were significantly higher than those in the control group(P<0.05). The yield component factors were correlated positively with seed yield, and the order of correlation was as follows: pod number/pod inflorescence>seed number/pod>pod inflorescence number/reproductive branches> number of reproductive branches per square meter. The stepwise regression equation of seed yield and yield component factors was Y=17.360+4.961X_(3)(Y was the seed yield, X_(3) was pod number/pod inflorescence, R^(2)=0.453 6, F=18.26^(**)). The results indicated that the yield of alfalfa seed could be increased by cutting treatment in the Qiqihar area of Heilongjiang Province. The pod number on pod inflorescence is the most important factor affecting the seed yield.