中国农业科学 ›› 2022, Vol. 55 ›› Issue (14): 2726-2739.doi: 10.3864/j.issn.0578-1752.2022.14.004

• 耕作栽培·生理生化·农业信息技术 • 上一篇    下一篇

翻耕深度对遮阴油菜根系生长和养分吸收利用的影响

白非1(),白桂萍2,王春云1,李真1,龚德平3,黄威4,程雨贵5,汪波1,王晶1,徐正华1,蒯婕1(),周广生1   

  1. 1.华中农业大学植物科学技术学院,武汉 430070
    2.襄阳市农业科学院,湖北襄阳441000
    3.荆州市农业科学院,湖北荆州 434000:
    4.黄冈市农业科学院,湖北黄冈438000:
    5.宜昌市农业科学研究院,湖北宜昌 420500
  • 收稿日期:2021-10-22 接受日期:2022-01-28 出版日期:2022-07-16 发布日期:2022-07-26
  • 联系方式: 白非,E-mail: 982895622@qq.com。
  • 基金资助:
    国家重点研发计划(2020YFD1000902);湖北省现代农业产业技术体系“稻田油菜高产高效技术创新与集成示范”项目

Effects of Tillage Depth and Shading on Root Growth and Nutrient Utilization of Rapeseed

BAI Fei1(),BAI GuiPing2,WANG ChunYun1,LI Zhen1,GONG DePing3,HUANG Wei4,CHENG YuGui5,WANG Bo1,WANG Jing1,XU ZhengHua1,KUAI Jie1(),ZHOU GuangSheng1   

  1. 1. College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070
    2. Xiangyang Academy of Agricultural Sciences, Xiangyang 441000, Hubei
    3. Jingzhou Academy of Agricultural Sciences, Jingzhou 434000, Hubei
    4. Huanggang Academy of Agricultural Sciences, Huanggang 438000, Hubei
    5. Yichang Academy of Agricultural Sciences, Yichang 420500, Hubei
  • Received:2021-10-22 Accepted:2022-01-28 Published:2022-07-16 Online:2022-07-26

摘要:

【目的】长江流域油菜季降雨丰沛,导致该地区光照强度下降,加之密植技术的推广,加剧了个体间对光照的竞争。故光照不足、土壤质地差成为制约该地区油菜高产的重要因素。通过研究耕作深度对遮阴油菜根系生长和养分利用的影响,以期为油菜的稳产增收提供理论支撑。【方法】2019—2021年在湖北武汉华中农业大学试验基地进行裂区试验,品种为主区(湘杂油518,XZY518;浙油50,ZY50),土壤翻耕深度(T5,5 cm;T20,20 cm)为副区,不同光照强度(S0,0%遮阴;S1,30%遮阴)为副副区,研究不同耕作深度下遮阴油菜的土壤养分和理化性质、干物质累积、抗氧化酶活性、根冠生长、养分吸收的变化。【结果】深耕可以促进各层土壤的有机质、碱解氮、速效磷和速效钾养分的积累,其中10—20 cm土壤的养分含量增幅最大,为7.5%—42.3%。两种翻耕深度下,遮阴均导致土壤电导率下降,根表面积减少13.3%—36.6%,主根长、根冠比和侧根占比增加,氮素利用率显著下降3.0%—28.4%,根系干重减少,抗氧化酶(POD、SOD、CAT)活性增加。遮阴条件下,翻耕深度的增加,使土壤含水量降幅减小,油菜主根伸长且根表面积增大,根冠比和侧根占比增加,氮素利用率提高,根系的抗氧化酶(POD、SOD)活性增强,干物质积累增多。方差分析表明翻耕深度和遮阴对根系形态、干物质累积、抗氧化酶活、养分利用的互作效应多呈显著或极显著水平。在浅耕和深耕条件下,与正常光照相比,遮阴导致根表面积分别下降24.9%—36.6%、13.3%—19.2%,氮素利用率分别下降10.0%—28.4%、3.0%—23.9%。【结论】弱光胁迫下,深耕通过提高各层土壤养分含量,使油菜主根伸长,侧根占比增加,根表面积增大,同时根系抗氧化酶活力的增强延缓了根系的衰老,使根系养分吸收能力增强,氮素利用率增大,干物质积累量增大,最终促进了油菜的生长。

关键词: 油菜, 遮阴, 深耕, 根系, 养分

Abstract:

【Objective】The rapeseed (Brassica napus L.) production district in the Yangtze River valley lacks sufficient radiation due to abundant rainfall during its growing season. In addition, the application of dense planting technology intensifies the competition for radiation among individuals. Insufficient radiation and poor soil texture have become main factors for restricting high yield of rapeseed in this area. In order to provide the theoretical support for stable yield and increased income, the effects of tillage depth on root growth and nutrient utilization of shaded rapeseed were studied. 【Method】 The experiment designed by the split-split plot method in three replications was conducted in the tested site of Huazhong Agricultural University in Wuhan, Hubei province, from 2019 to 2021. The experiment consisted of three factors arranged in a split-split plot design with 2 varieties: Xiangzayou 518 (XZY518) and Zheyou 50 (ZY50) in main plots, two levels of tillage depth: 5 cm (T5) and 20 cm (T20) in sub plots, and two levels of shading rate: 0% shading (S0) and 30% shading (S1) in sub-sub plots. The effects of different tillage depths on physical and chemical properties of soil, the antioxidant enzyme activity, nutrient absorption of the root and the dry matter accumulation of root and shoot were evaluated. 【Result】Deep tillage promoted the accumulation of organic matter, alkali-hydrolyzed nitrogen, available phosphorus, and available potassium in each layer of soil, with the largest increase (by 7.5%-42.3%) in 10-20 cm soil. Shading decreased the soil electrical conductivity, root surface area (decrease by 13.3%-36.6%), the utilization efficiency of nitrogen (decrease by 3.0%-28.4%) and root dry weight, while it increased the main root length, root to shoot ratio, lateral root proportion, and the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) in roots. The increasing tillage depth in shading condition alleviated the reduction of soil water content, promoted taproot elongation, increased the activities of antioxidant enzymes (POD and SOD) and the root surface area, root to shoot ratio, lateral root ratio finally improved the utilization efficiency of nitrogen, and the accumulation of dry matter. The analysis of variance showed that the interaction between tillage depth and shading on root morphology, dry matter accumulation, antioxidant enzyme activity and nutrient utilization reached a significant or extremely significant difference. Compared with normal light, the root surface area were decreased by 24.9%-36.6% and 13.3%-19.2%, the utilization efficiency of nitrogen were decreased by 10.0%-28.4% and 3.0%-23.9% after shading under the shallow tillage and deep tillage, respectively. 【Conclusion】Under the weak light stress, the deep tillage increased soil nutrients and main root elongation, the ratio of lateral root and root surface area, the activity of antioxidant enzymes in the root, dry matter accumulation, and enhanced the nutrient absorption capacity and nitrogen use efficiency, also delayed the aging of the root system. As a result, all these factors promoted rapeseed growth.

Key words: rapeseed, shade, deep tillage, root, nutrient