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

Area of Science:

• Agricultural Science
• Crop Modeling
• Plant Physiology

Background:

• Traditional crop models often underestimate rape yield due to neglecting photosynthesis in non-foliar organs.
• Accurate yield simulation is crucial for optimizing agricultural practices and food security.

Purpose of the Study:

• To develop and validate improved crop model calibration methods for rape yield estimation.
• To account for the photosynthetic contribution of siliques (pods) in rape plants.

Main Methods:

• Proposed Total Photosynthetic Area Index (TPAI) as a replacement for Leaf Area Index (LAI).
• Developed two calibration methods: TPAI-SPA (specific pod area) and TPAI-Curve (curve fitting).
• Validated methods using two years of field data in southern Hunan.

Main Results:

• Both TPAI-SPA and TPAI-Curve methods significantly improved rape yield estimation accuracy.
• TPAI-SPA increased estimation accuracy (R²) for total weight of storage organs (TWSO) by 9.68% and above-ground biomass (TAGP) by 49.86%.
• TPAI-Curve increased estimation accuracy (R²) for TWSO by 14.04% and TAGP by 42.94%.

Conclusions:

• The proposed TPAI-based calibration methods enhance the accuracy of rape yield simulation.
• These methods offer a novel approach for crop growth models in oilseed crop yield estimation.
• The study has practical importance for improving the precision of agricultural yield predictions.