Influence of plant development stage, temperature, and plant hormones on chromosome doubling of barley haploids using colchicine

Abstract

Varying colchicine treatments in the direction of earlier developmental stages, higher temperatures, and addition of N-6-benzyl adenine (BA) was without effect on percent of surviving plants that set seed. However, all three factors did increase the extent of doubling within the plant. This increase in size of doubled sectors suggests that the addition of BA and the shift to higher temperatures stimulate cell divisions in meristematic regions. The addition of gibberellic acid (GA₃), on the other hand, led to a decrease in size of doubled sectors. Comparisons among experiments, although nonorthogonal for genotype, confirmed that GA₃ increased plant survival after colchicine treatment and indicated that BA had a similar effect at 20 to 22 °C. However, the combination of high temperature (32 °C) and addition of BA increased plant lethality following colchicine treatment.