WHEAT CHROMOSOMES WITH GENES FOR PHOTOPERIODIC RESPONSE

Abstract

The 21 chromosome substitution lines of the wheat variety "Hope" in "Chinese Spring" were used to locate chromosomes of "Hope" determining the difference in photo-periodic response between these 2 var. Five chromosomes of "Hope" caused a significant alteration in photoperiodic response of "Chinese Spring". Three of these chromosomes, 1A, 4B and 6B bore genes which were more sensitive to short photoperiod than those on their homologues in "Chinese Spring" while the other 2 chromosomes, 3B and 7D, bore genes which were more insensitive to short photoperiod than those on their "Chinese Spring" homologues. On the assumption of there being only one gene/chromosome of the 5 chromosomes influencing the difference in photoperiodic response between these 2 var., the gene on chromosome 4B could be regarded as of major effect while those on the other 4 chromosomes could be comparatively regarded as of minor, or modifying influence.