Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, The Key Laboratory of Biology and Genetics Improvement of Horticultural Crops, Ministry of Agriculture; 12 Zhongguancun, Nandajie, Haidian District, 100081, Beijing, China.
Central Laboratory of Organic Agriculture, Agricultural Research Centre (Affiliation ID: 60019332), 9 Gamaa Street, 12619, Giza, Egypt.
Sci Rep. 2020 Mar 17;10(1):4867. doi: 10.1038/s41598-020-61564-4.
High callus production is a feasible way to improve the propagation coefficient of garlic. It remains unknown how genotypes and explants affect garlic callus formation. In the present investigation, we found that there were significant differences in callus formation among garlic varieties. Tip explants were the best calli-producing source, and 91.05% of the explants from four varieties, on average, formed calli after 45 d of primary culturing. Upper leaf parts explants produced lower values. Among the different varieties and explant types, tip explants of variety T141 induced calli in the shortest time and had the greatest callus fresh weight at 45 d. An endogenous hormone contents analysis showed that auxins (indole-3-acetic acid and methyl indole-3-acetic acetate), cytokinins (trans-zeatin and dihydrozeatin), gibberellins, abscisic acid, jasmonic acid, jasmonoyl-L-isoleucine, and dihydrojasmonic acid were significantly greater in the tips than those in the upper leaf parts. High endogenous jasmonic acid content might play important roles in callus formation. These results will help us not only establish an efficient garlic callus induction protocol that can be applied to large-scale callus multiplication and regeneration, and to genetically improvement of garlic production, but also understand endogenous hormone roles in tissue/organ differentiation and dedifferentiation.
高愈伤组织产量是提高大蒜繁殖系数的可行方法。基因型和外植体如何影响大蒜愈伤组织的形成尚不清楚。在本研究中，我们发现大蒜品种之间的愈伤组织形成存在显著差异。顶芽外植体是最佳的愈伤组织产生源，四个品种的外植体平均有 91.05%在初代培养 45 天后形成愈伤组织。上叶部分的外植体产生的数值较低。在不同的品种和外植体类型中，T141 品种的顶芽外植体在最短的时间内诱导愈伤组织形成，在 45 天时的愈伤组织鲜重最大。内源激素含量分析表明，生长素（吲哚-3-乙酸和甲基吲哚-3-乙酸）、细胞分裂素（反式玉米素和二氢玉米素）、赤霉素、脱落酸、茉莉酸、茉莉酰-L-异亮氨酸和二氢茉莉酸在顶芽中的含量明显高于上叶部分。高内源茉莉酸含量可能在愈伤组织形成中发挥重要作用。这些结果不仅有助于我们建立一种高效的大蒜愈伤组织诱导方案，可应用于大规模的愈伤组织增殖和再生，以及大蒜生产的遗传改良，还有助于我们了解内源激素在组织/器官分化和去分化中的作用。
