Heterosis in Cepaea

The inheritance of some characters in Cepaea hortensis and Cepaea nemoralis (Gastropoda).

N recent years the remarkable polymorphism of snails of the genus Cepaea IHeld has continued to attract considerable attention. The variation from place to place in the proportions of the different phenotypes has proved to be useful material for the study of evolution in natural populations (CAIN and SHEPPARD 1950, 1954; CLARKE 1960; CLARKE and MURRAY 1962; LAMOTTE 1951, 1959; SCHNETTER 195 1 ;...

MITOCHONDRIAL HETEROSIS IN MAIZE1p2

M A N Y hybrids between genetic pure lines in maize exhibit heterosis. The search for the genetic basis of heterosis has been carried on for many years and by many workers. Despite these efforts, an adequate, specific biochemical explanation of heterosis has not been presented. JONES (1952) has noted the interaction of nuclear genes and cytoplasm, as evidenced by differences in reciprocal cross...

Candidate genes for shell colour polymorphism in Cepaea nemoralis

The characteristic ground colour and banding patterns on shells of the land snail Cepaea nemoralis form a classic study system for genetics and adaptation as it varies widely between individuals. We use RNAseq analysis to identify candidate genes underlying this polymorphism. We sequenced cDNA from the foot and the mantle (the shell-producing tissue) of four individuals of two phenotypes and pr...

Cepaea hortenSiS (O. F. Müller, 1774) (MOllusCa: GastrOpODa) IN CrOatIa?

Heterosis: Theory and Estimation

Heterosis is the foundation of modern maize breeding programs. Despite its importance in maize production, we know surprisingly little about the genetic basis of heterosis. Shull (1952) coined the term heterosis and defined it as: "... the interpretation of increased vigor, size, fruitfulness, speed of development, resistance to disease and to insect pests, or to climatic rigors of any kind, ma...