Leaf chlorophyll and nitrogen dynamics and their relationship to lowland rice yield for site-specific paddy management  

作　　者：Asa Gholizadeh Mohammadmehdi Saberioon Lubos Boruvka Aimrun Wayayok Mohd Amin Mohd Soom 

机构地区：[1]Department of Soil Science and Soil Protection,Faculty of Agrobiology,Food and Natural Resources,Czech University of Life Sciences Prague,Prague,Czech Republic [2]Laboratory of Signal and Image Processing,Institute of Complex Systems,South Bohemia Research Centre of Aquaculture and Biodiversity of Hydrocenoses,Faculty of Fisheries and Protection of Waters,University of South Bohemia in Ceske Budejovice,Nove Hrady,Czech Republic [3]Department of Biological and Agricultural Engineering,Faculty of Engineering,University Putra Malaysia,Selangor,Malaysia [4]Faculty of Sustainable Agriculture,University Malaysia Sabah,Sandakan,Malaysia

出　　处：《Information Processing in Agriculture》2017年第4期259-268,共10页农业信息处理（英文）

基　　金：the partially financial support of the Ministry of Education,Youth and Sport of the Czech Republic-projects‘CENAKVA’(project No.CZ.1.05/2.1.00/01.0024),‘CENAKVA II’(project No.LO1205 under the NPU I program).

摘　　要：The optimum rate and application timing of Nitrogen(N)fertilizer are crucial in achieving a high yield in rice cultivation;however,conventional laboratory testing of plant nutrients is time-consuming and expensive.To develop a site-specific spatial variable rate application method to overcome the limitations of traditional techniques,especially in fields under a double-cropping system,this study focused on the relationship between Soil Plant Analysis Development(SPAD)chlorophyll meter readings and N content in leaves during different growth stages to introduce the most suitable stage for assessment of crop N and prediction of rice yield.The SPAD readings and leaf N content were measured on the uppermost fully expanded leaf at panicle formation and booting stages.Grain yield was also measured at the end of the season.The analysis of variance,variogram,and kriging were calculated to determine the variability of attributes and their relationship,and finally,variability maps were created.Significant linear relationships were observed between attributes,with the same trends in different sampling dates;however,accuracy of semivariance estimation reduces with the growth stage.Results of the study also implied that there was a better relationship between rice leaf N content(R^2=0.93),as well as yield(R2=0.81),with SPAD readings at the panicle formation stage.Therefore,the SPAD-based evaluation of N status and prediction of rice yield is more reliable on this stage rather than at the booting stage.This study proved that the application of SPAD chlorophyll meter paves the way for real-time paddy N management and grain yield estimation.It can be reliably exploited in precision agriculture of paddy fields under double-cropping cultivation to understand and control spatial variations.

关 键 词：Spatial variability Non-invasive measurement Precision farming Decision support 

分 类 号：S51[农业科学—作物学]