Interaction between Bean and Colletotrichum gloeosporioides: Understanding Through a Biochemical Approach

Area of Science:

• Plant Pathology
• Plant Physiology
• Biochemistry

Background:

• Nitric oxide (NO) is an emerging signaling molecule in plants, crucial for physiological processes like seed germination, development, and defense.
• Understanding the biochemical basis of plant defense responses is vital for managing crop diseases.

Purpose of the Study:

• To investigate the biochemical defense response activation in bean leaves during *Colletotrichum gloeosporioides* infection.
• To elucidate the role of nitric oxide (NO) and reactive oxygen species (ROS) in bean anthracnose development.

Main Methods:

• Detached bean leaves were inoculated with *Colletotrichum gloeosporioides* to establish infection stages.
• Biochemical analysis of defense-related enzymes, phenols, flavonoids, callose, lignin, NO, and ROS (H₂O₂) was performed.
• Assessment of stress markers including lipid peroxidation, proline, and chlorophyll content.

Main Results:

• Early stages of pathogen invasion showed up-regulation of NO, defense enzymes, phenols, flavonoids, callose, and lignin.
• Later disease stages exhibited down-regulation of NO and most defense components, except lignin, with elevated H₂O₂ production.
• Changes in lipid peroxidation, proline, and chlorophyll content correlated with disease progression and defense molecule levels.

Conclusions:

• Nitric oxide (NO) and reactive oxygen species (ROS) are involved in the plant defense response to *Colletotrichum gloeosporioides*.
• The dynamic interplay between NO, ROS, and other defense molecules influences the development of anthracnose in common bean.