| 摘要: |
| 为探讨主季高粱种植密度和氮肥用量对高粱再生产量的影响，以‘晋渝糯3号’为供试材料，设置3个种植密度8.25万(LD)、10.5万(MD)和12.75万株/hm2(HD)和3个施氮水平120(LN)、150(MN)和225 kg/hm2(HN)，测定再生季高粱再生力、干物质积累与转运特性、再生产量及其构成因素。结果表明，再生芽数和芽长随主季高梁种植密度的增加而减少，随施氮量的增加而增加。开花期和成熟期再生高粱单株干物质积累量均随密度的增大而减小，随施氮量的增加而增大。增加密度显著降低叶片花前干物质转运量、花前干物质转运率和花前干物质转运量对籽粒的贡献率，提高花后干物质积累量对籽粒的贡献率。增施氮肥降低叶片和茎鞘花前干物质转运率和花前干物质转运量对籽粒的贡献率，增加花后干物质积累量及其对籽粒的贡献率。再生高粱产量随密度和施氮量的增加而增加，HD分别比LD、MD的2年平均产量高17.82%和1.49%，HN分别比LN、MN的2年平均产量高24.23%和14.72%。单穗重随密度的增加而减少，随施氮量的增加而增加；千粒重在不同密度处理之间无显著差异，但随施氮量的增加而增加。综上，重庆市主季高粱种植密度12.75万株/hm2和施氮量225 kg/hm2可获得较高再生产量。 |
| 关键词: 高粱 种植密度 施氮量 再生力 再生产量 |
| DOI：10.11841/j.issn.1007-4333.2021.08.05 |
| 投稿时间：2020-08-25 |
| 基金项目:重庆市科研院所绩效激励引导专项(cstc2018jxjl80008,cqaas2019jxjl02)；重庆市自然科学基金(cstc2019jcyj-msxmX0125) |
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| Effects of planting density and nitrogen rate in main season on ratooning yield of sorghum |
|
ZHOU Yu,LI Zebi,ZHANG Yaqin,WU Yu,HUANG Juan
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| (Institute of Characteristic Crops Research, Chongqing Academy of Agricultural Sciences, Chongqing 402160, China) |
| Abstract: |
| In order to study the effects of different planting densities and nitrogen rates in main season on the yield of ratoon sorghum, the sorghum hybrid ‘Jinyunuo 3' was taken as study material under 3 planting densities, 82 500(LD), 105 000(MD), 127 500 plant/hm2(HD), and 3 nitrogen rates, 120(LN), 150(MN), 225 kg/hm2(HN). The ratooning ability, dry matter accumulation characteristics, yield and yield components of ratoon sorghum were investigated. The results showed that the number and length of regeneration buds decreased with the increase of planting density, while increased with the increase of nitrogen rate. The dry matter accumulation of ratoon sorghum decreased with the increase of planting density and increased with the increase of nitrogen rate at both anthesis and mature stages. The higher planting density reduced dry matter transportation and dry matter transportation efficiency of leaf before anthesis and its contribution to grain, but improved the contribution of dry matter accumulation after anthesis to grain. The higher nitrogen rate reduced dry matter transportation efficiency of leaf and stem+sheath before anthesis, as well as their contribution to grain, but boosted the contribution of dry matter accumulation after anthesis to grain. The yield of ratoon sorghum increased with the lifting of planting density and nitrogen rate. The average yield of ratoon sorghum under HD was respectively 17. 82% and 1. 49% higher than those under LD and MD for two years. The average yield of ratoon sorghum under HN was respectively 24. 23% and 14. 72% higher than those under LN and MN. The ear weight decreased with the increase of planting density, but increased with the increase of nitrogen rate. The 1 000-grain weight showed no significant difference among planting densities, while it increased with the increase of nitrogen rate. In conclusion, under the experimental field condition in this study, the planting density of 127 500 plant/hm2 and nitrogen rate of 225 kg/hm2 could obtain higher yield of ratoon sorghum. |
| Key words: sorghum planting density nitrogen rate ratooning ability ratooning yield |
