Graduate Research Assistant, Department of Crop and Soil Sciences, Michigan State University, 48824, East Lansing, MI, USA.
Plant Cell Rep. 1989 Apr;8(4):222-5. doi: 10.1007/BF00778538.
Sugarbeet plants representing 14 of 16 germplasm sources (4 to 5 plants per source) produced callus from leaf disks on a hormone-free Murashige and Skoog based medium. Overall, 49.2% of explants from partially expanded leaves of whole plants initiated callus (53 of 74 plants tested), in an average time of 96.7 days. The time to callus was considerably longer than the 4-6 weeks observed when 1 mg/L N(6)-benzyladenine has been used in the medium. Shoots were regenerated on the hormone-free medium without subculture from callus of eight individual genotypes, representing 3 of the 14 populations that produced callus. Shoots produced by 'Gartons White Knight' and 'L53' appeared to be of somatic embryo origin. Rhizogenic calli were also produced by the same three populations that regenerated shoots. Significant differences among populations were found for frequency of root formation from leaf disks and time to callus. Variation among plants within a population was significant for four of the five traits examined. The results indicate the ease of hormone autonomization in sugarbeet, and should be of value in designing regeneration media for a wider range of beet germplasm.
甜菜植株代表 16 个种质资源中的 14 个（每个资源 4-5 株），在无激素 Murashige 和 Skoog 基础培养基上从叶片圆盘产生愈伤组织。总体而言，74 株试验植株中有 49.2%（53 株）来自部分展开的整株叶片的外植体启动了愈伤组织，平均时间为 96.7 天。与在培养基中使用 1 mg/L N(6)-苄基腺嘌呤时观察到的 4-6 周相比，愈伤组织的时间要长得多。来自产生愈伤组织的 8 个个体基因型的愈伤组织在无激素培养基上无需继代培养即可再生出芽。来自 'Gartons White Knight' 和 'L53' 的芽似乎来自体细胞胚胎的起源。同样的三个种群也产生了生根的愈伤组织。在叶片圆盘生根频率和愈伤组织形成时间方面，种群之间存在显著差异。在五个检查的性状中，有四个在种群内的植物之间存在显著差异。结果表明，甜菜中激素自主化很容易，这对于设计更广泛的甜菜种质资源的再生培养基应该是有价值的。
