582 PB 091 PLANT REGENERATION FROM EMBRYOGENIC CALLUS TISSUES OF KENTUCKY BLUEGRASS

Abstract

Coleoptile tissues from dark-germinated seedlings of Kentucky bluegrass (Poa pratensis L.) cv. Touchdown were excised and cultured on MS medium supplemented with 1.5-2.5 mg/liter picloram plus 0.2 mg/liter benzyladenine (BA) or with 4 mg/liter 2,4-D. Embryogenic calli were formed on media containing 1.5 mg/liter picloram plus 2.5 mg/liter 2,4-D in the dark. When these embryogenic calli were subcultured on MS medium containing either 0.15-0.3 mg/liter picloram or 0.2-0.5 mg/liter 2,4-D in a 16-h day/8-h night photoperiod, 10.5% of the cultures regenerated shoots. Pretreatment of cultures in the dark for 2 weeks prior to light exposure slightly increased the plant regeneration efficiency to 15.5%. Pigmentation of the regenerants varied with a ratio of 8.5 completely green: 2.5 green plus albino: 1 completely albino plants. The shoots were multiplied in the medium containing 0.5 mg/liter BA plus either 0.2 mg/liter picloram or 0.1 mg/liter indoleacetic acid (IAA). Over 90% cultures in the shoot proliferation medium produced roots after 4 weeks.