杂交构树茎段组织培养体系的建立

Establishment of tissue culture system of hybrid Broussonetia papyrifera(L.) Vent.

以杂交构树[Broussonetia papyrifera (L.) Vent.]——中科一号为试验材料,通过对杂交构树茎段的离体培养和扩繁,探究了不同激素配比对杂交构树诱导愈伤、丛生芽、壮苗和生根的影响。试验结果表明,以具腋芽的构树茎段为外植体材料,75%乙醇溶液浸泡40 s后,再经0.3%HgCl2灭菌15 min,外植体的成活率可达44%;诱导愈伤组织的最佳培养基为MS+IBA 0.5 mg/L+6-BA 2.0 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,愈伤诱导率达90%;诱导丛生芽的最佳培养基为MS+IBA 1.5 mg/L+6-BA2.0 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,丛生芽增殖系数为4.2,生长势较好;壮苗的最佳培养基为MS+IBA 0.2 mg/L+6-BA 1.5 mg/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,平均株高4.8 cm;生根的最佳培养基为1/2 MS+IBA 0.8 mg/L+活性炭1.5 g/L+马铃薯50 g/L+蔗糖25 g/L+琼脂7.0 g/L,pH 5.6～5.8,生根率100%。最佳的炼苗移栽基质土为珍珠岩∶蛭石∶草炭=1∶1∶1的混合基质,幼苗生长得最好,平均株高为7.3 cm。

The hybrid tree[Broussonetia papyrifera (L.) Vent.]-Zhongke No. 1 was used as the experimental material, through the culture and expansion of the stem segments of the hybrid tree in vitro, the effects of different hormones on callus, shoot buds, strong seedlings and roots were studied. The results showed that the survival rate of explant material, stems of the buds with axillary buds, could reach 44%, after immersed in 75% ethanol solution for 40 s, then sterilized by 0.3% HgCl2 for 15 min. The optimal medium for inducing callus is MS+IBA 0.5 mg/L+6-BA 2.0 mg/L+sucrose 25 g/L+agar 7.0 g/L, pH 5.6~5.8, the callus induction rate reached 90%. The optimal medium for inducing cluster buds was MS+IBA 1.5 mg/L+6-BA 2.0 mg/L+sucrose 25 g/L+agar 7.0 g/L,pH 5.6~5.8, the growth coefficient of cluster buds is 4.2, and the growth potential is good. The optimal medium for strong seedlings is MS+0.2 mg/L IBA+6-BA 1.5 mg/L+sucrose 25 g/L+agar 7.0 g/L, pH 5.6~5.8, average plant height is 4.8 cm. The optimal medium for rooting is 1/2 MS+IBA 0.8 mg/L+activated carbon 1.5 g/L+potato 50 g/L+sucrose 25 g/L+agar 7.0 g/L,pH 5.6~5.8, rooting rate is 100%. The best seedling transplanting substrate soil is a mixed substrate of peat∶perlite∶vermiculite=1∶1∶1. The seedlings grow best, with an average plant height of 7.3 cm.