影响大白菜离体培养再生频率各因素的探讨

Studies on factors that influence the shoots regeneration ratio of Brassica Campestris cultured in vitro

本实验以大白菜“０２号杂交早皇白”无菌苗的子叶作为材料，就组织培养过程中影响芽再分化的各种因素进行了初步探讨．用附加ＢＡ４．４×１０－６～３５．５×１０－６ｍｏｌ／Ｌ、ＮＡＡ０．５４×１０－６～３．２×１０－６ｍｏｌ／Ｌ、ＡｇＮＯ３１．２×１０－５ｍｏｌ／Ｌ的ＭＳ培养基培养子叶切段，能直接－诱导分化出芽和根；３～１１ｄ苗龄的子叶芽分化率稳定在８０％以上，其中４～５ｄ苗龄的效果较好；子叶比下胚轴易产生愈伤组织和再生芽；整片子叶比子叶切段易诱导分化出芽．芽分化率最高可达９７．８％．但每个外植体平均芽数以切去子叶柄的子叶切段为多．激素配比以ＢＡ８．９×１０－６ｍｏｌ／Ｌ、 ＮＡＡ２．７×１０－６ｍｏｌ／Ｌ为最好，在此培养基中再添加８．４×１０－５ｍｏｌ／ＬＣｏ（ＮＯ３）２对促进芽分化有一定作用，但效果不如ＡｇＮＯ３。

In this paper are studied the many factors that influence shoots regeneration ratio of in vitro cultured Brassica Campestris. It has been found that its sterile cotyledons could directly Induce shoots and roots from cotyledon segments in MS culture media added with BA4. 4×10-6 ~ 35. 5 ×106 mol/L, NAA0. 54× 10-6 ~ 3. 2× 10-6 mol/L and AgNO3 1. 2× 10-5 mol/L; that over 80% of the cotyledons of 3-to-11-days-old remained stable and among them those of 4-to-5-days-old were the best; that cotyledons could generate callus and shoot more readily than hypocotyl; that shoots could be induced more readily from the whole cotyledon than from colyledon segment,with the highest regeneration ratio of 97. 8; and yet for any of the explant the average number of shoots was greater in cotyledon segments with their petioles cut off. It has also been found that the optimum hormone match wss BA8. 9× 10-6 mol/L + NAA2. 7× 10-6 mol/L and that the addition of 8. 4×10-5 mol/L of Co(NO3)2 to the culture medium would have some effect on shoots regeneration,but the result was not as good as the addition of AgNO3.