Research Article | Open Access

Volume 2024 |Article ID 0253 | https://doi.org/10.34133/plantphenomics.0253

Rape Yield Estimation Considering Non-Foliar Green Organs Based on the General Crop Growth Model

Shiwei Ruan,^1,5 Hong Cao,^2,3,5 Shangrong Wu ,^2,3 Yujing Ma,¹ Wenjuan Li,^2,3 Yong Jin,¹ Hui Deng,^2,3 Guipeng Chen,⁴ Wenbin Wu,^2,3 Peng Yang^2,3

¹School of Information and Communication Engineering, North University of China, Taiyuan 030051, China
²State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China (theInstitute of Agricultural Resources and Regional Planning), Chinese Academy of Agricultural Sciences,Beijing 100081, China
³Key Laboratory of Agricultural Remote Sensing, Ministry of Agriculture and RuralAffairs/Institute of Agricultural Resources and Regional Planning, Chinese Academy of AgriculturalSciences, Beijing 100081, China
⁴Institute of Agricultural Economics and Information, Jiangxi Academyof Agricultural Sciences, Nanchang 330200, China
⁵These authors contributed equally to this work

Abstract

To address the underestimation of rape yield by traditional gramineous crop yield simulation methods based on crop models, this study used the WOFOST crop model to estimate rape yield in the main producing areas of southern Hunan based on 2 years of field-measured data, with consideration given to the photosynthesis of siliques, which are non-foliar green organs. First, the total photosynthetic area index (TPAI), which considers the photosynthesis of siliques, was proposed as a substitute for the leaf area index (LAI) as the calibration variable in the model. Two parameter calibration methods were subsequently proposed, both of which consider photosynthesis by siliques: the TPAI-SPA method, which is based on the TPAI coupled with a specific pod area, and the TPAI-Curve method, which is based on the TPAI and curve fitting. Finally, the 2 proposed parameter calibration methods were validated via 2 years of observed rape data. The results indicate that compared with traditional LAI-based crop model calibration methods, the TPAI-SPA and TPAI-Curve methods can improve the accuracy of rape yield estimation. The estimation accuracy (R2) for the total weight of storage organs (TWSO) and above-ground biomass (TAGP) increased by 9.68% and 49.86%, respectively, for the TPAI-SPA method and by 14.04% and 42.94%, respectively, for the TPAI-Curve method. Thus, the 2 calibration methods proposed in this study are of important practical importance for improving the accuracy of rape yield simulations. This study provides a novel technical approach for utilizing crop growth models in the yield estimation of oilseed crops.