Leaf productivity and persistence have been improved during soybean (Glycine max) domestication and evolution

Area of Science:

• Plant biology
• Agricultural science
• Evolutionary biology

Background:

• Soybean (Glycine max (L.) Merr. subsp. max) leaf traits have been altered by artificial and natural selection.
• Potential trade-offs between leaf productivity and leaf persistence traits may exist due to shared resource allocation.

Purpose of the Study:

• To investigate potential trade-offs between soybean leaf productivity and persistence traits during domestication and evolution.
• To determine if selection for increased leaf photosynthetic rate has negatively impacted leaf longevity.

Main Methods:

• A three-year experiment comparing one wild soybean line with three domesticated lines (landrace, old cultivar, modern cultivar).
• Analysis of leaf traits related to productivity (photosynthetic rate, nitrogen content, stomatal conductance) and persistence (lifespan, mass per unit area, bulk density).

Main Results:

• Some leaf trait values increased, while others showed no significant change during domestication.
• Productivity-related and persistence-related leaf traits were not negatively correlated.
• Changes in productivity and persistence traits occurred at different times, indicating independent selection.

Conclusions:

• Soybean leaf productivity and persistence traits have been independently selected for, without trade-offs.
• Combining high leaf productivity and high leaf persistence can enhance lifetime leaf carbon gain.
• This independent selection offers potential for increased soybean yield through simultaneous improvement of both trait groups.