Biotech Studies 1994, Vol 3, Num, 1-2     (Pages: 113-129)

DETERMINATION OF ED50 AND LD50 OF CALLAND AND MITCHELL SOYBEAN VARIETIES AFTER GAMMA IRRADIATION

Zafer SAĞEL

1 Dr. TAEK Ankara Nükleer Araş. ve Eği. Merk. Nükleer Tarım Bl. - Greenhouse and field experiments were conducted during 1986 to investigate the effects of different gamma irradiation doses on the percent, emergence, plant height, plant dry matter and survived plants of Calland and Mitchell soybean varieties. Seeds that were used in the greenhouse experiments were irradiated at 9 doses ranging from O to 700 Gray, meanwhile the seeds that used in the field experiments were irradiated at doses ranging from 0-400 Gray. For gamma irradiation 60Co source was used. Results obtained for M1 generation in the greenhouse showed that percent emergence was not effected with increasing radiation doses; however under field conditions percent emergence was significantly effected. Although varying with variety, plant height and plant dry matter decreased as the dose increased, in the greenhouse; survived plants under field conditions were decreased with increasing radiation doses. Generally, negative effects of increasing radiation doses were obtained for the mentioned percent emergence, plant height, plant dry matter and survived plants in the M1 generation. The dose that decreases growth by 50 percent (ED50) for Calland and Mitchell were found to be 245 and 250 Gray, respectively. Meanwhile the letal dose that kills 50 percent of the plants (LD50) for Calland and Mitchell were found to be 350 and 330 Gray, respectively. Keywords : Gamma irradiation; gray; cobalt (60Co); soybean; M1 generation