Genotypes suppressing meiotic drive of a B-chromosome in the mealybug, Pseudococcus obscurus

Genotypes suppressing meiotic drive of a B-chromosome in the mealybug, Pseudococcus obscurus

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Nur, UB, B. L. H.,  Genetics,  110:73-92. 1985.

The rate of transmission (k) of a supernumerary B chromosome in male mealybugs is shown tq depend strongly on the chromosome set of materpal origin. When both parents came from an isofemale line in which the frequency of the B chromosome increased rapidly and stabilized at a mean of more than 4.0 B chromosomes per individual, was 0,92 and 0.95 in two series of crosses. However, when the female parent came from one of two isofemale lines in which the frequency of the B chromosome decreased from 2.0 to 0 in a few generations, R ranged from 0.53 to 0.78. The high ks, which represent a strong meiotic drive, are apparently responsible for the observed increase in the frequency of the B chromosome in several lines from a mean of about 0.5 to more than 4.0 in about 20 generations. The rapid loss of the B chromosome in other lines is attributed to genetic factors which caused the reduction in the rate of transmission qf the B chromosome.