Has yield plasticity already been exploited by soybean breeding programmes in Argentina?

Area of Science:

• Agricultural Science
• Plant Breeding
• Genetics

Background:

• Soybean (Glycine max L.) yield potential is influenced by genetic improvements and environmental factors.
• Seed yield plasticity, the ability of a genotype to vary yield across environments, is crucial for stable agricultural productivity.
• High-yielding environments in Central Argentina (4000–7000 kg ha-1) present unique challenges and opportunities for soybean breeding.

Purpose of the Study:

• To analyze the impact of genetic improvement on soybean seed yield plasticity in high-yielding environments.
• To investigate the association between seed yield and its plasticity over time.
• To understand the relationship between seed yield plasticity and the seed-filling period.

Main Methods:

• Analysis of 148 historical soybean genotypes (1980–2013) and 165 commercial genotypes.
• Evaluation of genetic progress in both lowest and highest yielding soybean genotypes.
• Statistical analysis to determine the correlation between seed yield plasticity, yield variability, and seed-filling period length.

Main Results:

• Soybean breeding programs in Argentina showed higher genetic progress in lower-yielding genotypes (1.7% year-1) compared to higher-yielding ones (0.9% year-1).
• Increased seed yield plasticity over time significantly reduced genotypic seed yield variability (P<0.0001).
• Seed yield plasticity was positively correlated with a longer seed-filling period (r=0.5) in environments exceeding 5500 kg ha-1.

Conclusions:

• Genetic improvement has indirectly enhanced soybean seed yield plasticity.
• Increased plasticity contributes to more stable soybean yields, particularly in high-yielding conditions.
• Exploiting seed yield plasticity and a longer seed-filling period can aid in developing superior soybean cultivars for high-yielding environments.