ササユリ未熟種子の胚から効率的に実生を育成するための組織培養条件の検討(繁殖・育苗)  [in Japanese] Study on the In Vitro Culture Conditions for Raising Seedlings from Embryos Excised from Immature Seeds of Lilium japonicum Thunb(Propagation & Transplant Production)  [in Japanese]

ササユリ未熟種子から摘出した胚の生育に及ぼす培養温度, 培地内のショ糖濃度, 固形化剤および植物生長調節物質の種類と添加濃度の影響について検討した.自然開花時に授粉して結実したさく果を9月上旬に採取し, 長さ3〜5mmに生長した胚を無菌的に摘出し, MS培地に置床して45μmol・m^<-2>・s^<-1>, 16時間照明下で培養した.胚の発芽, 生育および小球形成に及ぼす培養温度は20〜25℃が良く, 培地へのショ糖添加量は3%, 固形化剤は0.8%寒天あるいは0.4%ゲランガムが再生植物体の生育に適していた.植物生長調節物質についてみると, 無添加培地でも植物体再生は可能であるが, KinetinおよびBA添加培地では胚の初期発育が促進された.IAA添加培地では再生植物の小球形成が進み, 1個の胚から複数の小球が形成された.従来の実生繁殖に比べ効率的に再生植物が得られる本手法は, ササユリの持続的で安定的な種苗養成法として有効である.

The effects of various such culture conditions as culture temperature, and concentration of sucrose, gelling reagents and plant growth regulators on the growth and development of embryos excised from immature seeds of Lilium japonicum Thunb. were examined. The embryos as cultured explants were obtained from the capsule in early September. Embryos with 3-5mm in length were cultured in vitro on Murashige and Skoog medium (pH 5.7) under controlled lighting conditions (45μmol・m^<-2>・s^<-1>, 16/8hr : light/dark). The optimal temperature for germination, growth and bulb formation was 20〜25℃. The plantlets were effectively established on MS hormone-free medium containing 3% sucrose and gelled with 0.8% agar or 0.4% gellan gum. Further-more, 1〜10μM of exogenous Kinetin or BA promoted embryo growth within 30 days of culture. 1〜10μM of exogenous IAA promoted multiple bulblet formation. The results indicate that our in vitro method for successfully raising plantlets can be efficiently applied to mass seedling propagation of Lilium japonicum Thunb.