【作者】 张旭；

【导师】 张新全； 聂刚；

【作者基本信息】 四川农业大学 ， 草学， 2019， 硕士

【摘要】 鸭茅（Dactylis glomerate）是世界上广泛种植的禾本科冷季性牧草,具有叶多高产、耐阴、适应性强、适口性好、营养价值高等优点,可用于混播草地放牧、青饲、调制干草或青贮。“滇北”鸭茅是四川农业大学新选育的优良品种,在西南区岩溶石漠化治理及人工草地建植中发挥着重要作用,种子需求量大。在种子生产中,由于鸭茅茎秆纤细,若开花结实期若遇风雨天气则会造成鸭茅的倒伏,影响种子产量。而喷施适宜浓度植物生长调节剂能增加生殖枝数目、小穗及小花数、降低株高,提高种子产量,对于鸭茅种子生产具有重要意义。本研究以“滇北”鸭茅为试验材料,在GS32时期（拔节早期）喷施植物生长调节剂。通过两年的大田试验探讨了不同浓度矮壮素(500、750、1000、1250g·hm^-2)、不同浓度抗倒酯(100、200、300、400g·hm^-2)及这两种植物生长调节剂的混合制剂(矮壮素和抗倒酯500+50、500+150、1000+50、1000+150g·hm^-2)对鸭茅种子产量的影响。试验结果表明:（1）喷施生长调节剂后能显著的提高鸭茅种子产量。喷施不同浓度矮壮素、抗倒酯及其混合制剂对“滇北”鸭茅种子产量均有提升。喷施矮壮素后鸭茅种子产量第1年最高为241.7kg·hm^-2,第2年最高为284.4kg·hm^-2,平均增产21.5%;喷施抗倒酯第1年最高为286.7 kg·hm^-2,第2年最高为299.4kg·hm^-2;混施矮壮素和抗倒酯第1年最高为291.3kg·hm^-2,增产46.2%,第2年产量达309.1 kg·hm^-2。（2）喷施不同浓度矮壮素、抗倒酯及其混合制剂对鸭茅种子产量构成因子有不同程度影响。喷施矮壮素后,单位面积的生殖枝数目与种子产量极显著相关,每平方米生殖枝数目最大值为168.3个;喷施抗倒酯后,种子产量与生殖枝数目、每小穗的小花数呈极显著正相关,每平方米生殖枝数目最高达184.0个,每小穗小花数最高为4.72朵;混施矮壮素和抗倒酯后,种子产量与生殖枝数目、每小穗小花数及结实率呈极显著正相关,结实率为三种生长调节剂中最高,达67.45%。此外,本试验中喷施生长调节剂对种子的千粒重、种子发芽率及发芽势没有显著影响。（3）在不同生长调节剂处理后,混施矮壮素和抗倒酯对“滇北”鸭茅种子增产效果最佳。以GS32时期混施矮壮素和抗倒酯两种生长调节剂(最佳混施浓度配比为500+150g·hm^-2),两年度分别较对照增产46.2%和32.5%,效果较单独喷施两种生长调节剂更为明显。此外,结果表明混施矮壮素和抗倒酯对“滇北”鸭茅种子增产的主要机制是通过增加单位面积生殖枝数目。更多还原

【Abstract】 Dactylis glomerata is also called orchardgrass.It’s a cold-season grass widely cultivated in the world.（Dactylis glomerata.cv Dian bei）is a new excellent variety bred by Sichuan Agricultural University.It plays an important role in rocky desertification control,artificial and mixed grassland construction,crop and forage rotation,grass planting under forests,returning farmland to grassland,soil and fertilizer cycle and other ecological restoration and environmental engineering in Southwest China.In the extension of agricultural production,the demand for seeds is huge.In this study,the plant growth regulators were sprayed on the orchardgrass during the GS32.From 2016 to 2018,field trials of different concentrations of CCC(500,750,1000,1250g·hm^-2),TE(100,200,300,400g·hm^-2)and mixture of TE+CCC(500+50、500+150、1000+50、1000+150g·hm^-2)were conducted in the fields.（1）All the growth regulators increased the seed yield of orchardgrass.After spraying CCC,the highest seed yield was 241.7 k g·hm^-2in the first year and 284.4 k g·hm^-2in the second year,with an average increase of 21.5%.After spraying TE,The highest was286.7 kg·hm^-2in the first year and 299.4 kg·hm^-2in the second year.After mixed application of CCC and TE,the highest yield was 291.3 kg·hm^-2in the first year,which increased 46.2%and reached 309.1 kg·hm^-2in the second year.（2）The correlation analysis showed that spraying three growth regulators had different effects on yield components of orchardgrass seeds.The seed yield was positively correlated with the number of reproductive branches and the number of florets per spikelet by TE.There was a significant positive correlation between seed yield and number of reproductive branches,number of florets per spikelet and seed setting rate by the mixture of TE+CCC.（3）Compared with the three kinds of growth regulators,the effect of mixed application of growth regulators was the most obvious.The yield increased by 46.2%and 32.5%in two years,which were the highest among the three kinds of growth regulators.At the GS32 stage,the best mixture of TE+CCC was used,and the best mixture concentration was 150+500 g·hm^-2.更多还原