Long-term maintenance in vitro of potato plantlets in nutrient media is necessary to preserve disease-free stocks. Since these are living plants, they eventually outgrow the containers they are in and exhaust the media, so propagation onto fresh media is required. To decrease labor and time spent in this process, it is of interest to slow plant growth to reduce turnover frequency. In this study, we investigated the effects of adding two concentrations (2 and 4%) of mannitol (a sugar alcohol that causes osmotic stress) to tissue culture media on plant growth of three potato clones at moderately low temperatures. Plantlet growth was inversely proportional to the concentration of mannitol used, but there were genotypic differences. Regeneration of the plantlets for subsequent micropropagation, after removal from the main treatments at day 64 and 121 days, was not negatively affected by the percentage of mannitol used to maintain the original stocks. Based on these results, we started using 2% mannitol as a baseline for practical long-term storage of potato breeding clones maintained in vitro. Depending on the reaction of the specific genotypes to media containing mannitol, additional adjustments might be needed.

中文翻译：

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将甘露醇掺入组织培养基中以在低温下长期保存马铃薯，并对随后的微繁育产生影响

为了保护无病种群，必须在营养培养基中长期维持马铃薯苗的离体。由于这些植物是有生命的植物，因此它们最终会超出其所在容器的大小，并耗尽了培养基，因此需要传播到新鲜的培养基上。为了减少此过程中的劳力和时间，降低植物生长速度以减少周转频率很重要。在这项研究中，我们研究了在中等低温下向组织培养基中添加两种浓度（2和4％）的甘露醇（一种引起渗透压的糖醇）对三个马铃薯无性系植物生长的影响。苗的生长与所用甘露醇的浓度成反比，但存在基因型差异。再生小植株以便随后的微繁殖，在第64天和第121天从主要处理中去除后，不受用于维持原始库存的甘露醇百分比的不利影响。基于这些结果，我们开始使用2％甘露醇作为基线，用于长期长期保存体外保存的马铃薯育种克隆。根据特定基因型与含甘露醇的培养基的反应，可能需要进行其他调整。