Combining Limited Multiple Environment Trials Data with Crop Modeling to Identify Widely Adaptable Rice Varieties

Area of Science:

• Agricultural Science
• Agronomy
• Crop Modeling

Background:

• Traditional Multi-Environment Trials (MET) for varietal evaluation are limited by the number of test environments.
• Accurate assessment of genotype by environment interactions is crucial for effective breeding programs.
• Developing advanced methods to evaluate crop performance across vast spatial and temporal scales is essential.

Purpose of the Study:

• To innovate a modeling approach using the ORYZA (v3) rice model for evaluating varietal performance in a large number of environments.
• To classify environments and analyze varietal yield and stability using modeled genotype by environment interactions.
• To compare the effectiveness of the modeling approach against traditional MET data.

Main Methods:

• Utilized the ORYZA (v3) crop model to simulate yields for eight Green Super Rice (GSR) and three check varieties across 3796 environments and 14 seasons in Southern Asia.
• Classified environments into nine Target Population of Environments (TPEs) based on drought stress in rainfed rice.
• Analyzed varietal performance, yield, and yield stability using modeled data and compared it with actual MET data.

Main Results:

• All GSR varieties, except one, demonstrated superior performance compared to check varieties across all TPEs.
• GSR-IR1-1-Y4-Y1 and GSR-IR1-8-S6-S3-Y2 consistently outperformed other varieties in all classified environments.
• ORYZA (v3)-based evaluation showed significant correspondence with actual MET data within sites but highlighted limitations for larger environments.

Conclusions:

• The ORYZA (v3) modeling approach effectively complements MET by enabling varietal performance assessment across a significantly larger number of spatial and temporal scales.
• This advanced modeling approach is reliable and can be adopted for other regions and crops, provided adequate soil and weather data are available.
• The study confirms the advantage of GSR varieties in diverse environmental conditions, supporting their wider adoption.