不同生境苦豆子种群的生产性能

The production characteristics of Sophora alopecuroides populations in different habitats

本研究重点比较了干旱和湿润生境下,苦豆子(Sophora alopecuroides)的草产量、种子产量、种子大小和种子硬实率等生产性能的指标和特性。在广泛分布地区选择5个测定地点,包括甘肃临泽、民勤,宁夏盐池,内蒙古阿拉善左旗和额济纳旗。结果表明,生长环境对苦豆子的生产性能影响很大;干旱生境的每分枝干草产量均小于湿润生境的,分别为4.9和7.2g,干旱生境与湿润生境单位面积的干草产量分别为1 330.7和1 546.1kg·hm^(-2);各地点单位面积与每分枝的种子产量、收获指数、硬实率和千粒重,均表现为干旱生境高于湿润生境,其中,干旱生境的平均实际种子产量和收获指数均显著高于湿润生境的(P<0.05),分别为335.0kg·hm^(-2)、1.2g·分枝-1和17.0%,是湿润生境的2.2、1.7和2.1倍;干旱生境的平均硬实率为91.0%,高于湿润生境5.7个百分点;干旱生境种子平均千粒重为19.5g,是湿润生境的1.3倍。两种生境的生殖枝密度和每荚果种子数均与单位面积种子产量呈极显著正相关(P<0.01)。依据本研究数据估测,我国苦豆子的干草总产量和种子产量分别为239.5万~278.3万t和27.8万~60.3万t。

In order to compare the production characteristics of Sophora alopecuroides from arid and moist habitats,the indices including herbage yields,seed yields,seed sizes and hard seed rates were measure for the samples from five positions in main distribution areas including Linze County and Minqin County,Gansu Province;Yanchi County,Ningxia Province;Left Banner and Ejina Banner of Alxa League,Inner Mongolia.The results showed that environments greatly affected the production characteristics of S.alopecuroides.The forage yield per branch（4.9g）in arid habitats was less than that（7.2g）in moist habitats.The average forage yield per unit area was 1 330.7kg·ha^（-1）in arid habitats and 1 546.1kg·ha^（-1）in moist habitats.The seed yields per area and branch,harvest indexes,hard seed rates and thousand seed weights in arid habitats were all higher than those in moist habitats.The average actual seed yield and harvest index were 335.0kg·ha^（-1）,1.2g per branch and 17.0%in arid habitat,which were significantly increased（P〈0.05）by 2.2,1.7and 2.1times than those in moist habitat.The average rate of hard seed in arid habitat was 91.0% which was 5.7% higher than that in moist habitat.The average thousand seed weight was 19.5g in arid habitat,which was 1.3times of that in moist habitat.In both two habitats,the fertile shoots density and seeds per pod had greatly significant correlations（P〈0.01）with seed yield per unit area.The nationwide herbage yield of S.alopecuroides was estimated to be 2 395 000~2 783 000 tons and the seed yield was estimated to 278 000~603 000 tons based on the measured data.