Deep placement of nitrogen fertilizer increases rice yield and nitrogen use efficiency with fewer greenhouse gas emissions in a mechanical direct-seeded cropping system

作     者：Lin Li Hua Tian Minghua Zhang Pingshan Fan Umair Ashraf Haidong Liu Xiongfei Chen Meiyang Duan Xiangru Tang Zaiman Wang Zheng Zhang Shenggang Pan Lin Li;Hua Tian;Minghua Zhang;Pingshan Fan;Umair Ashraf;Haidong Liu;Xiongfei Chen;Meiyang Duan;Xiangru Tang;Zaiman Wang;Zheng Zhang;Shenggang Pan

作者机构：State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresourcesCollege of AgricultureSouth China Agricultural UniversityGuangzhou 510642GuangdongChina Scientific Observing and Experimental Station of Crop Cultivation in South ChinaMinistry of AgricultureGuangzhou 510642GuangdongChina Guangzhou Key Laboratory for Science and Technology of Fragrant RiceGuangzhou 510642GuangdongChina Key Laboratory of Key Technology for South Agricultural Machine and EquipmentMinistry of EducationGuangzhou 510642GuangdongChina College of Tropical CropsHainan UniversityHaikou 570228HainanChina Department of BotanyDivision of Science and TechnologyUniversity of EducationLahore 54770PunjabPakistan Hezhou Academy of Agricultural SciencesHezhou 542800GuangxiChina School of EngineeringJiangxi Agricultural UniversityNanchang 330045JiangxiChina 

出 版 物：《The Crop Journal》 (作物学报（英文版）)

年 卷 期：2021年第9卷第6期

页      面：1386-1396页

核心收录：

学科分类：09[农学] 0901[农学-作物学] 

基　　金：supported by the Key-Area Research and Development Program of Guangdong Province(2019B020221003) National Natural Science Foundation of Guangdong Province(008175187004) National Natural Science Foundation of China(31471442) 

主　　题：N placement Grain yield Nitrogen use efficiency Greenhouse gas Direct-seeded rice 

摘      要：Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons(March–July) of 2016 and *** experimental treatments comprised two rice cultivars: Wufengyou 615(WFY 615) and Yuxiangyouzhan(YXYZ), and three N treatments: mechanical deep placement of all fertilizers as basal dose at 10 cm soil depth(one-time deep-placement fertilization, namely OTDP fertilization);manual surface broadcast(the common farmer practice) of 40% N fertilizer at one day before sowing(basal fertilizer)followed by broadcast application of 30% each at tillering and panicle initiation stages;and no fertilizer application at any growth stage as a control. One-time deep-placement fertilization increased grain yield of both rice cultivars by 11.8%–19.6%, total nitrogen accumulation by 10.3%–13.1%, nitrogen grain production efficiency by 29.7%–31.5%, nitrogen harvest index by 27.8%–30.0%, nitrogen agronomic efficiency by 71.3%–77.2%, and nitrogen recovery efficiency by 42.4%–56.7% for both rice cultivars, compared with the multiple-broadcast treatment. One-time deep-placement fertilization reduced CH4-induced global warming potential(GWP) by 20.7%–25.3%, N2O-induced GWP by 7.2%–12.3%, and total GWP by 14.7%–22.9% for both rice cultivars relative to the multiple-broadcast treatment. The activities of glutamine synthetase and nitrate reductase were increased at both panicle-initiation and heading stages in both rice cultivars following one-time deep-placement fertilization treatment. Larger leaf area index at heading stage and more favorable root morphological traits expressed as larger total root length, mean root diameter, and total root volume per hill were also observed. One-time deep-placement fertilization could be an effective strategy for increasing grain yield and nitrogen use efficiency and lowering greenhouse-gas emissions under mechanical direct-seeded cropping systems.