Question

In the gene-for-gene model proposed by Harold Flor, what does the relationship between the plant and pathogen involve?

A) One gene in the plant matches with multiple genes in the pathogen
B) One gene in the pathogen matches with multiple genes in the plant
C) Each gene in the plant corresponds to a specific gene in the pathogen
D) The relationship is entirely random and not based on specific genes

Answer 1

The gene-for-gene model involves a one-to-one correspondence between each resistance gene in a plant and a specific avirulence gene in a pathogen, leading to a highly specific host-pathogen interaction that triggers the plant's defense mechanisms.

Step-by-step explanation:

In the gene-for-gene model proposed by Harold Flor, the relationship between the plant and pathogen involves each gene in the plant corresponding to a specific gene in the pathogen. This implies a highly specific interaction where the presence of a particular resistance gene in a plant will have a corresponding avirulence gene in the pathogen. Host-pathogen interactions are well-studied in biology as they provide insight into how diseases are resisted by plants and also the mechanisms pathogens use to overcome these defenses. When a matching pair is present, the plant can recognize the pathogen and activate defense mechanisms, often rendering the plant resistant to the pathogen. The correspondence is not arbitrary or random, nor does it involve one gene matching with multiple counterparts on the other side.