Evolution: Replicated mutation of COL2 contributed long-day flowering in common bean.

Area of Science:

• Plant biology
• Genetics
• Crop science

Background:

• Flowering time is a critical trait for crop adaptation to diverse environments.
• Daylength sensitivity historically limited crop cultivation ranges.
• Common bean (Phaseolus vulgaris) is a globally important legume crop.

Purpose of the Study:

• To investigate the genetic basis of daylength insensitivity in common bean.
• To understand the evolutionary selection of flowering time adaptations in crops.
• To identify the molecular mechanisms underlying altered flowering responses.

Main Methods:

• Analysis of common bean germplasm from Central and South America.
• Identification and characterization of mutations in flowering time regulatory genes.
• Genetic mapping and sequencing of key transcription factors.

Main Results:

• Repeated selection of mutant alleles for a transcription factor suppressing long-day flowering was identified.
• These mutations confer daylength-insensitive flowering.
• This adaptation facilitated the spread of common bean cultivation.

Conclusions:

• Mutations in a key transcription factor are responsible for daylength-insensitive flowering in common bean.
• This genetic adaptation has been crucial for the crop's global expansion.
• Understanding these mechanisms can inform future crop breeding strategies.