Tomato ethylene sensitivity determines interaction with plant growth-promoting bacteria

Area of Science:

• Plant Science
• Microbiology
• Biochemistry

Background:

• Plant growth-promoting bacteria (PGPB) enhance plant physiology and development.
• The role of ethylene sensitivity in PGPB-plant interactions is not well understood.

Purpose of the Study:

• To determine if ethylene perception is critical for plant-bacteria interactions and growth induction by two PGPB strains.
• To assess the physiological effects of PGPB strains on juvenile and mature tomato plants.

Main Methods:

• Experiment using ethylene-insensitive tomato (never ripe) and wild-type lines.
• Inoculation with Bacillus megaterium or Enterobacter sp. C7.
• Analysis of biomass, photosynthesis, and nutritional/metabolic status at juvenile and mature stages.

Main Results:

• Bacillus megaterium promoted growth only in mature wild-type plants.
• Enterobacter C7 affected both wild-type and ethylene-insensitive plants.
• Ethylene insensitivity impaired B. megaterium activity but Enterobacter C7 improved nitrogen assimilation in insensitive plants.

Conclusions:

• Ethylene sensitivity is crucial for B. megaterium's PGPB activity in tomato.
• Enterobacter C7's growth-promoting effects are independent of ethylene perception.
• Enterobacter C7 enhances nitrogen assimilation in ethylene-insensitive plants.