IMPROVED PRODUCTION OF DOUBLED HAPLOIDS BY COLCHICINE APPLICATION TO WHEAT (TRITICUM-AESTIVUM L.) ANTHER CULTURE

The aim of this study was to optimize the in vitro chromosome-doubling procedure in wheat anther culture. Colchicine, at concentrations of 1 00-5000 mg/l, was added to the induction medium for 1-5 days. Benefici al effects were obtained with concentrations of 100 and 1000 mg/l colc hicine. With time, significant reductions in embryo-like structures as well as higher doubling indices were found. Similar results were obta ined with the high- and low-responding genotypes. Colchicine (100 mg/l ), added 5 and 20 days after inoculation for 1 and 3 days increased th e induction response, but this value was reduced when colchicine was a dded 10 or 15 days after inoculation. The doubling effect was similar to the control, except for a significant increase with the 3-day appli cation 20 days after inoculation. The highest success index was reache d when colchicine was added to the culture medium after 20 days.