Fecundity and longevity of F 1 females of Habrobracon from sperm x-rayed with 3000r.

Abstract

Abstract Our purpose was to compare with respect to fecundity and longevity two groups of F1 diploid virgins of Habrobracon the fathers of which had been X-rayed with 3000r. Sorting of wasps into two groups was based on low or high hatchability of their F2 haploid eggs. Wasps with low hatchability (below 60%) are heterozygous for induced embryonic lethals such as recessives and translocations; wasps with high hatchability (100–60%) are free of lethals or possibly heterozygous for mild detrimentals. The F1s showing high hatchability laid significantly more eggs on the average; the average difference in lifespan was almost statistically significant (7% level). A more sensitive analysis by regression indicated a highly significant linear regression of survival of all F1s on hatchability of their eggs: F1s whose eggs showed 100% hatchability lived 1.84 days longer on the average than those whose eggs showed no hatchability. Furthermore, the former laid 4.99 more eggs on the average than the latter. The data also showed a very highly significant positive correlation coefficient between eggs laid and survival of mothers (0.122***) and a very highly significant positive partial correlation coefficient (0.105***) with hatchability held constant. The latter indicates that the F1s which laid more eggs also live longer, regardless of the hatchability of their eggs and hence of the heterozygosity of the mothers for lethals and other detrimentals.