Cytogenetics of Lolium perenne : Part 3. Correlation between chiasmata and U-type exchange.

In two contrasting types of S5 inbred Lolium perenne a correlation has been found between the distribution pattern of chiasmata within bivalents and that of meiotic U-type exchange. The relationship between the two processes is discussed, in terms of inbreeding effects upon chiasma redistribution, and mention is also made of some other types of chromosome breakages which arise following enforced self-pollination.