甘农4号紫花苜蓿组培再生体系的建立

Establishing regeneration systems of Gannong No.4 alfalfa

为实现对甘农4号紫花苜蓿Medicagosativacv．Gannong No．4的遗传改良，研究拟建立一个操作简便、可重复性强、遗传性稳定、培养周期短和再生率高的转基因受体系统，为其遗传改良奠定基础。研究以MS为基本培养基，在不同浓度的2，4-D与6-BA的诱导培养基上，以甘农4号紫花苜蓿下胚轴为外植体，诱导愈伤组织。诱导率为86．85％～99．56％，其中MS＋2mg／L 2，4-D＋1mg／L 6-BA诱导率最高；浅黄色至淡绿色的愈伤组织在MS＋0．5mg／LKT＋0．1mg／LNAA培养基上的分化最好且植株颜色嫩绿。丛生芽在1／2MS＋0．5mg／LNAA的生根培养基上可再生成完整的苜蓿植株。

Hypocotyls of Gannong No. 4 alfalfa were used as explants, MS was used as the basic medium, different concentration of 2,4-D and 6-BA were added into the medium to induce the callus. The rate of inducement ranged from 86. 85% to 99.56%, the treatment of MS＋2 mg/L 2,4-D ＋ 0.5 mg/L 6-BA had the highest inducement rate; yellow and green callus had best differentiation on the medium of MS＋0.5 mg/L KT＋0.1 mg/L NAA, and the color of plants was tenderly green. The regenerated plants were obtained in the root inducing medium （1/2MS＋0. ,5 mg/L NAA）.