PLASTID STRUCTURE, CHLOROPHYLL CONCENTRATION, AND FREE AMINO ACID COMPOSITION OF A CHLOROPHYLL MUTANT OF BARLEY

Abstract

Biochemical properties and chloroplast fine-structure of a viridis mutant of Gateway barley are described. The mutant was deficient in chlorophyll and carotenoids when young but developed nearly normal levels of pigment with age (a virescens type). Etiolated mutant seedlings were low in protochlorophyll. In the young mutant, chloroplasts were small and irregular in shape and they contained large vesicles but no normal lamellae or grana. The level of free amino acids, particularly of serine, was extremely high. These disturbances were overcome with age. It is suggested that the mutation alters the lipoprotein of lamellar structures in the plastid, and that other effects are consequential.