Abdalla Neama, Dobránszki Judit
Plant Biotechnology Department, Biotechnology Research Institute, National Research Centre, 33 El Buhouth St., Dokki, Giza 12622, Egypt.
Centre for Agricultural Genomics and Biotechnology, Faculty of Agriculture and Food Sciences and Environmental Management, University of Debrecen, 4400 Nyíregyháza, Hungary.
Plants (Basel). 2024 Jun 6;13(11):1568. doi: 10.3390/plants13111568.
In vitro mass propagation of apple plants plays an important role in the rapid multiplication of genetically uniform, disease-free scions and rootstocks with desired traits. Successful micropropagation of apple using axillary shoot cultures is influenced by several factors, the most critical of which is the cytokinin included in the culture medium. The impact of medium composition from single added cytokinins on shoot proliferation of apple scion Húsvéti rozmaring cultured on agar-agar gelled Murashige and Skoog medium fortified with indole butyric acid and gibberellic acid was investigated. The optimum concentration for efficient shoot multiplication differs according to the type of cytokinin. The highest significant multiplication rate (5.40 shoots/explant) was achieved using 2.0 μM thidiazuron while the longest shoots (1.80 cm) were observed on the medium containing benzyladenine at a concentration of 2.0 μM. However, application of either thidiazuron or benzyladenine as cytokinin source in the medium resulted in shoots of low quality, such as stunted and thickened shoots with small leaves. In the case of benzyladenine riboside, the 8 μM concentration was the most effective in increasing the multiplication rate (4.76 shoots/explant) but caused thickened stem development with tiny leaves. In the present study, -topolin was shown to be the most effective cytokinin that could be applied to induce sufficient multiplication (3.28 shoots/explant) and high-quality shoots along with shoot lengths of 1.46 cm when it was applied at concentrations of 4 μM. However, kinetin was the least active cytokinin; it practically did not induce the development of new shoots. The superior cytokinin for in vitro axillary shoot development of apple scion Húsvéti rozmaring with high-quality shoots was the -topolin, but it may be different depending on the variety/genotype under study.
苹果植株的离体大规模繁殖在快速繁殖具有所需性状的基因一致、无病接穗和砧木方面发挥着重要作用。利用腋芽培养成功进行苹果微繁殖受多种因素影响，其中最关键的是培养基中所含的细胞分裂素。研究了在添加吲哚丁酸和赤霉素的琼脂凝胶化的Murashige和Skoog培养基上培养的苹果接穗Húsvéti rozmaring，单一添加细胞分裂素的培养基组成对其芽增殖的影响。有效芽增殖的最佳浓度因细胞分裂素类型而异。使用2.0 μM噻苯隆可实现最高的显著增殖率（5.40个芽/外植体），而在含有2.0 μM苄基腺嘌呤的培养基上观察到最长的芽（1.80厘米）。然而，在培养基中使用噻苯隆或苄基腺嘌呤作为细胞分裂素来源会导致芽质量较低，如矮化和增粗的芽以及小叶。对于苄基腺嘌呤核糖苷，8 μM浓度在提高增殖率（4.76个芽/外植体）方面最有效，但会导致茎增粗并伴有小叶发育。在本研究中，当以4 μM浓度施用时，-Topolin被证明是最有效的细胞分裂素，可诱导足够的增殖（3.28个芽/外植体）和高质量的芽，芽长为1.46厘米。然而，激动素是活性最低的细胞分裂素；它实际上不会诱导新芽的发育。对于苹果接穗Húsvéti rozmaring离体腋芽发育而言，能产生高质量芽的优质细胞分裂素是-Topolin，但根据所研究的品种/基因型不同可能会有所差异。
