Genetic consequences of the couplet cytoplasmic pollen sterility and pollen migration.

ATSON and CASPARI (1960) developed a mathematical model to study the VU behavior of cytoplasmic pollen sterility in populations. They dealt with a population possessing two kinds of cytoplasm and pollen sterility resulting from an interaction of the recessive homozygote with one of the cytoplasms. Under these conditions the frequencies of the maternally transmitted cytoplasms remained unchanged; however, the plasmon-sensitive allele was eliminated. GRUN and AUBERTIN (1965) studying different South American potato species found cytoplasm-gene-conditioned pollen sterility and proposed that it could keep populations genetically isolated if pollen migration of sterility-conditioning genes occurred. CASPARI, WATSON and SMITH (1966) then extended their initial analysis by employing a computer simulation in which seed migration was studied. Their models yielded no evidence that pollen sterility could restrict gene flow between populations. It is the objective of this communication to analytically extend the WATSONCASPARI model to include pollen migration and to evaluate the joint effects of cytoplasmic pollen sterility coupled with pollen migration.