Pullman Gerald S, Chase Kelly-Marie, Skryabina Anna, Bucalo Kylie
School of Biology and Institute of Paper Science and Technology, Georgia Institute of Technology, 500 10th Street N.W., Atlanta, GA 30332-0620, USA.
Tree Physiol. 2009 Jan;29(1):147-56. doi: 10.1093/treephys/tpn013. Epub 2008 Dec 5.
A major barrier to the commercialization of somatic embryogenesis technology in loblolly pine (LP, Pinus taeda L.) is recalcitrance of some high-value crosses to initiate embryogenic tissue and to continue early-stage somatic embryo growth. Developing initiation and multiplication media that resemble the seed environment may decrease this recalcitrance. Sugar and sugar alcohol analyses were performed weekly throughout the sequence of seed development for female gametophyte and zygotic embryo tissues to determine physiologic concentrations (Pullman, G.S. and M. Buchanan. 2008. Identification and quantitative analysis of stage-specific carbohydrates in LP (Pinus taeda) zygotic embryo and female gametophyte tissues. Tree Physiol. 28:985-996). Major differences in stage-specific sugars were observed. A simple bioassay was used to evaluate the potential growth promotion of individual carbohydrates added to initiation or multiplication media at physiologic concentrations. Seventeen sugars were screened. Compounds showing statistically significant increases in early-stage embryo growth were then tested for the ability to increase the initiation of LP. d-xylose and d-chiro-inositol produced statistically significant increases in early-stage embryo growth. When tested for improved initiation in P. taeda, Pseudotsuga menziesii (mirb) Franco and Picea abies L., Karst., d-xylose increased the averages of initiation by 6.5%, 7.3% and 16.7%, respectively. d-chiro-inositol increased the initiation in P. taeda by 7.3% in one test but not in the other, whereas in P. menziesii the initiation increases averaged 8.4% in two tests. Analyses of sugars and sugar alcohols in the seed environment coupled with a bioassay to screen potential media supplements for protocol improvement resulted in statistically significant increases in embryogenic tissue initiation for several coniferous species.
火炬松（LP，Pinus taeda L.）体细胞胚胎发生技术商业化的一个主要障碍是，一些高价值杂交种难以启动胚性组织并持续早期体细胞胚胎生长。开发类似于种子环境的启动和增殖培养基可能会降低这种顽拗性。在种子发育的整个过程中，每周对雌配子体和合子胚组织进行糖和糖醇分析，以确定生理浓度（Pullman, G.S. 和 M. Buchanan. 2008. LP（Pinus taeda）合子胚和雌配子体组织中阶段特异性碳水化合物的鉴定和定量分析。树木生理学。28:985 - 996）。观察到阶段特异性糖存在重大差异。使用一种简单的生物测定法来评估以生理浓度添加到启动或增殖培养基中的单个碳水化合物的潜在生长促进作用。筛选了17种糖。然后测试了在早期胚胎生长中显示出统计学显著增加的化合物增加火炬松启动的能力。d - 木糖和d - 手性肌醇在早期胚胎生长中产生了统计学显著的增加。当测试其对火炬松、北美云杉（Pseudotsuga menziesii (mirb) Franco）和欧洲云杉（Picea abies L., Karst.）启动的改善效果时，d - 木糖分别使启动平均值提高了6.5%、7.3%和16.7%。d - 手性肌醇在一项测试中使火炬松的启动增加了7.3%，但在另一项测试中未增加，而在北美云杉中，两项测试中启动增加的平均值为8.4%。对种子环境中的糖和糖醇进行分析，并结合生物测定法来筛选用于改进方案的潜在培养基补充剂，结果使几种针叶树种的胚性组织启动有了统计学显著的增加。
