Results are given of genetic studies of male sterility using plants from two natural populations from Sussex, England. Both populations have substantial frequencies of females, approximately 0.25 in population 1 and 0.60 in population 3. As in the few other gynodioecious populations studied in detail, many genetic factors are present. In population 1, there are at least two, and more likely thr...

Reproductive isolation between species is often caused by deleterious interactions among loci in hybrids. Finding the genes involved in these incompatibilities provides insight into the mechanisms of speciation. With recently diverged subspecies, house mice provide a powerful system for understanding the genetics of reproductive isolation early in the speciation process. Although previous studi...

Though cytoplasmic male sterility (CMS) in peppers is associated with the orf507 gene, definitive and direct evidence that it directly causes male sterility is still lacking. In this study, differences in histochemical localization of anther cytochrome c oxidase between the pepper CMS line and maintainer line were observed mainly in the tapetal cells and tapetal membrane. Inducible and specific...

Gellhorn, Hill, Moeschlin, and Wintrobe-were in close agreement regarding the indications for and therapy of leukemia. This book is almost an encyclopedia in this particular branch of hematology. The reader will be impressed by the ingenuity and the amount of information it contains. Another of its assets is that one obtains good insight into the character and type of work being undertaken in t...

HREE different kinds of hybrid sterility of males occur within the superspecies Drosophila ptzulistorum Dobzhansky and Pavan, and a fourth one will he described in the present paper. The superspecies consists of at least five races or incipient species (DOBZHANSKY and SPASSKY 1959). The F, hybrids between these races are fertile if females and sterile if males. This is a sterility of the genic ...