Stability and utilization of picloram, vitamins, and sucrose in a tissue culture medium

Abstract

Nicotinic acid, pyridoxine, and picloram were stable in a liquid MS culture medium (pH 5.5–5.6) during autoclaving and during cell-free incubation in the dark at 5°C or 25°C for up to 6 weeks. Thiamine loss under the same conditions was 16% at 5°C and 18% at 25°C. Five percent of the sucrose in the liquid medium was hydrolyzed during autoclaving. During cell-free incubation in the light (100 μE m⁻² s⁻¹) at 25°C, pyridoxine was not detected after 6 days, while 78% of the picloram and 56% of the thiamine were degraded after 6 weeks. All of the niacin and pyridoxine, 13% of the picloram and 42% of the thiamine in a liquid MS culture medium were utilized in 4 days by potato (cv. Lemhi Russet) tuber suspension cultures growing in the dark at 25°C.