Recessive resistance to plant viruses

Area of Science:

• Plant Pathology
• Genetics
• Molecular Biology

Background:

• Recessive resistance genes are vital for managing plant viral diseases, with about half of known genes inherited recessively.
• Understanding recessive resistance mechanisms at the single-cell and cell-to-cell movement levels is advancing rapidly.

Purpose of the Study:

• To review recent characterizations of loss-of-susceptibility and recessive resistance genes in crop and model species.
• To discuss actual and probable recessive resistance mechanisms.
• To summarize the current state-of-the-art and future perspectives in plant virus resistance.

Main Methods:

• Analysis of host/virus interactions in crop species.
• Cloning and characterization of recessive resistance genes.
• Identification and study of loss-of-susceptibility mutants.

Main Results:

• Many cloned recessive resistance genes encode translation initiation factors (eIF4E and eIF4G).
• Not all identified mutants correspond to eIF4E or eIF4G, suggesting other factors are involved.
• Recessive resistance impacts virus multiplication and movement within plant cells.

Conclusions:

• Recessive resistance genes, particularly those related to translation initiation, are key targets for crop improvement against viral pathogens.
• Further investigation into natural genetic variation is essential for discovering novel host factors conferring recessive resistance.
• Continued research will refine our understanding of plant virus resistance mechanisms and breeding strategies.