Breeding of Fruit and Plantation Crops

Genetic control of self incompatibility

• Incompatibility is generally controlled by a special gene at S-locus represented by multiple allelic series in the population.
  
• Each of these alleles control the formation of a specific substance that determines the incompatibility reactions, both in the pistil and pollen.
  
• Identical substances specified by identical genes in pollen and pistil favour to prevent fertilization.
  
• Based on the timing and mode of S-gene activity, the incompatibility reaction among homomorphic angiosperm is categorized into two groups.
1. Gametophytic control of pollen reaction.
2. Sporophytic control of pollen reaction.