Apoplastic interactions between plants and plant root intruders

Area of Science:

• Plant Pathology
• Plant-Parasite Interactions
• Molecular Plant-Microbe Interactions

Background:

• Plant roots are attacked by various pathogenic and parasitic organisms.
• The apoplast, including the plant cell wall, is a critical interface for plant-parasite interactions.
• Root parasitic angiosperms (e.g., Striga, Orobanche) and plant-parasitic nematodes pose significant agricultural threats.

Purpose of the Study:

• To review recent advances in understanding the role of apoplastic signals in plant-parasite interactions.
• To highlight the importance of plant cell walls in the context of parasitic invasions.
• To discuss common strategies employed by different root parasites to breach plant defenses.

Main Methods:

• Review of existing literature on plant-parasite interactions, focusing on apoplastic communication and cell wall degradation.
• Analysis of mechanisms used by parasitic plants and nematodes to invade host roots.
• Discussion of host plant defense responses and parasite effector strategies.

Main Results:

• Parasitic plants form haustoria expressing plant cell wall degrading enzymes (PCWDEs).
• Plant-parasitic nematodes use a stylet to secrete PCWDEs and apoplastic effectors.
• Apoplastic signals, such as strigolactones, mediate communication between plants and parasites.

Conclusions:

• The apoplast and plant cell walls are central to the invasion strategies of diverse root parasites.
• Understanding these interactions is key to developing strategies against parasitic angiosperms and nematodes.
• Apoplastic signals play vital roles in plant defense and parasite development.