THE ACTION OF THE INTENSIFIER (IN) GENE IN FLAVONOID PRODUCTION IN ALEURONE TISSUE OF MAIZE

Abstract

The intensifier (in) allele in the homozygous recessive condition, in the appropriate genetic background, accentuates the formation of anthocyanin pigments in the aleurone tissue of maize. In a comparative genetic analysis with In and in combinations of five gene loci of the anthocyanin pathway, A, A2, Bz, Bz2, and Pr, in single and double recessive condition, it was possible to determine the effect of in on the expression of these genes in terms of the quality and quantity of the accumulated pigments. It was found that the recessive in greatly increases the quantity of anthocyanins, 3-deoxy anthocyanins, and leucoanthocyanidins in appropriate genotypes. On the contrary, in did not cause any qualitative differences in the pigment composition. The in showed a dosage effect in increasing the pigment levels. Also, observations were made on the interaction pattern of in with certain controlling-element alleles of the En system. A significant increase in the pigment content was observed due to the in effect without any qualitative changes. The nature of in action and its position in the anthocyanin pathway is discussed in the light of these data.