Behavior of an extra chromosome carried by alloplasmic common wheat lines having Agropyron trichophorum cytoplasm

Abstract

All the alloplasmic common wheat lines having Agropyron trichophorum cytoplasm were found to carry one extra submetacentric or telocentric chromosome although they had been backcrossed seven times with common wheat as the pollen parent. Behavior of the extra chromosome and its interaction with the A, trichophorum cytoplasm were studied. A, trichophorum cytoplasm was found to induce seed shriveling and severe vigor reduction in common wheat. The extra chromosome originating from A, trichophorum carries a gene(s) for complete restoration of seed plumpness and normal plant vigor. Conscious selection of plump seeds and vigorous plants for backcrossing has resulted in the preferential transmission of the A. trichophorum chromosome in the present alloplasmic lines.