生长调节剂对羊草生长及种子产量的影响

摘要

通过田间试验研究了不同浓度多效唑(PP333)、矮壮素(CCC)和抗倒酯(TE)对人工种植的二年龄羊草(Leymus chinensis)生长及种子产量性状的影响.结果表明:在羊草分蘖期施用多效唑、矮壮素和抗倒酯均使羊草株高、穗长降低,而生殖枝数、基部茎粗、小穗数和种子产量增加,且以多效唑处理效果最明显.生长调节剂种类与浓度对羊草种子产量有显著影响.当处理浓度为0.6,1.2和1.8kg/hm2时,多效唑处理种子产量比对照分别增长1.63,3.32和4.18倍(P＜0.05);矮壮素处理种子产量比对照分别增长16.10％,113.12％和161.43％ (P＜0.05);抗倒酯在1.8 kg/hm2处理下种子产量比对照增长103.98％(P＜0.05),其余浓度间种子产量差异不显著(P＞0.05).在12个处理组合中,多效唑喷施浓度为1.8 kg/hm2处理种子产量最高(260.6 kg/hm2),其次为多效唑喷施浓度为1.2 kg/hm2处理(217.3 kg/hm2).因高浓度(1.8 kg/hm2)多效唑处理对羊草生长抑制较重以及土壤残留药剂较多等问题,在羊草分蘖期喷施1.2 kg/hm2多效唑较适宜.%A field experiment was conducted to study the effect of paclobutrazol (PP333),chlormequat chloride (CCC) and trinexapac-ethyl (TE) on growth characteristics and seed yield of Leymus chinensis with different concentrations.The results showed that PP333,CCC and TE decreased the plant height,spike length,ratio of stem and increased fertile tillers,basal stem diameter,pikelet and seed yield,and PP333 treatment was the best.Spraying PP333 in tillering stage significantly reduced aboveground biomass (P＜0.01).Types and applied concentration of plant growth regulator significantly affected on seed yield.When the application rate of growth regulator was 0.6,1.2 and 1.8 kg/ha,seed yield were 1.63,3.32 and 4.18 times higher respectively than those of CK group under PP333 treatment (P＜0.05),and were 16.10％ (P＞0.05),113.12％ and 161.43％ (P＜ 0.05) higher respectively than those of CK group under CCC treatment.Seed yield of TE treatment were 103.98％ (P＜0.05) higher than those of CK group at 1.8 kg/ha concentration (P＜0.05).In the 12 treatment combinations,A1B4 produced the highest seed yield (260.6 kg/ha),followed by A1B3 treatment (217.3 kg/hm2).In consideration of growth inhibition and soil residual medication under high concentration (1.8 kg/ha) of PP333,1.2 kg/ha PP333 was the suitable application rate.