Mirzaei Leila, Yadollahi Abbas, Kermani Maryam Jafarkhani, Naderpour Masoud, Zeinanloo Ali Asghar, Farsi Maryam, Davoodi Dariush
Department of Horticultural Sciences, Faculty of Agriculture, Tarbiat Modares University (TMU), P. O. Box: 14115-111, Tehran, Iran.
Department of Cell and Tissue Culture, Agricultural Research, Education and Extension Organization (AREEO), Agricultural Biotechnology Research Institute of Iran (ABRII), P. O. Box: 31535-1897, Karaj, Iran.
Plant Methods. 2021 Mar 29;17(1):31. doi: 10.1186/s13007-021-00724-7.
In vitro culture of olive, as an economically valuable tree, has fundamentally a genotype-dependant low micropropagation rate which needs to be improved in already established and newly released cultivars. Various plant tissue culture media, planting systems and growth factors were evaluated in two promissing Iranian olive cultivars 'Amin' and 'Meshkat' and the commercial Spanish cultivar 'Arbequina'.
The results showed that cultivars have their specific optimal media, i.e. 'Amin' in the MS with 4 mg/L zeatin, 'Arbequina' in the OM with 1 mg/L zeatin, and 'Meshkat' in the OM and MS with 2 mg/L zeatin, which produced significantly a higher number of axillary shoots than other media. The results also indicated a significant improvement in the growth indices of 'Amin' (number of axillary shoots) when cultured using periodical mini bioreactor (PMB) in the VS medium. In comparison with VS, OM did not reveal any significant differences when both culturing systems (PMB and semi-solid media (SSM)) were used. Regarding the effect of carbon source and light intensity, mannitol and 2000 cd sr m greatly enhanced 'Arbequina' growth indices (main shoot length and growth quality). The results of genetic stability of callus induced shoots (CIS) and meristem induced shoots (MIS) revealed that 2C DNA value assessed by partec flow cytometery (FCM) had 0.01, 0.03 and 0.08 pg discrepencies in 'Amin', 'Arbequina' and 'Meshkat', repectively. The Amplified Fragment Length Polymorphism (AFLP) results also indicated that the cultivars were classified regardless of the micropropagation origin (CIS or MIS), except for 'Arbequina'. The AFLP findings showed that 'Arbequina' had the highest dispersal (7-38%) in CIS and MIS, while the Iranian cultivar of 'Meshkat' (5-9%) had the highest stability.
This study indicated the importance of in vitro growth parameters for improving the micropropagation indices of olive cultivars. It showed that optimized protocols (OM, PMB, zeatin, mannitol and 2000 cd sr m) co-produced larger calli resulting in indirect organogenesis. Based on FCM and AFLP analysis, it can be concluded that true-to-typeness of micropropagated olive was cultivar-dependent.
油橄榄作为一种具有经济价值的树种，其离体培养从根本上来说受基因型限制，微繁殖率较低，这在已有的和新培育的品种中都需要得到改善。在两个有前景的伊朗油橄榄品种“Amin”和“Meshkat”以及西班牙商业品种“Arbequina”中，对各种植物组织培养基、种植系统和生长因子进行了评估。
结果表明，不同品种有其特定的最佳培养基，即“Amin”在添加4毫克/升玉米素的MS培养基中，“Arbequina”在添加1毫克/升玉米素的OM培养基中，“Meshkat”在添加2毫克/升玉米素的OM和MS培养基中，这些培养基产生的腋芽数量明显高于其他培养基。结果还表明，在VS培养基中使用定期微型生物反应器（PMB）培养时，“Amin”的生长指标（腋芽数量）有显著改善。与VS相比，当使用两种培养系统（PMB和半固体培养基（SSM））时，OM没有显示出任何显著差异。关于碳源和光照强度的影响，甘露醇和2000勒克斯显著提高了“Arbequina”的生长指标（主茎长度和生长质量）。愈伤组织诱导芽（CIS）和分生组织诱导芽（MIS）的遗传稳定性结果表明，通过帕泰克流式细胞仪（FCM）评估的2C DNA值在“Amin”、“Arbequina”和“Meshkat”中分别有0.01、0.03和0.08皮克的差异。扩增片段长度多态性（AFLP）结果还表明，除了“Arbequina”之外，无论微繁殖起源（CIS或MIS）如何，这些品种都能被分类。AFLP结果显示，“Arbequina”在CIS和MIS中的分散度最高（7 - 38%），而伊朗品种“Meshkat”（5 - 9%）的稳定性最高。
本研究表明了离体生长参数对提高油橄榄品种微繁殖指标的重要性。研究表明，优化的方案（OM、PMB、玉米素、甘露醇和2000勒克斯）共同产生了更大的愈伤组织，从而导致间接器官发生。基于FCM和AFLP分析，可以得出结论，微繁殖油橄榄的真实性取决于品种。
