Gautam Sanjeev, Solis-Gracia Nora, Teale Megan K, Mandadi Kranthi, da Silva Jorge A, Vales M Isabel
Department of Horticultural Sciences, Texas A&M University, College Station, TX, United States.
Texas A&M AgriLife Research & Extension Center at Weslaco, Weslaco, TX, United States.
Front Plant Sci. 2021 Aug 11;12:700328. doi: 10.3389/fpls.2021.700328. eCollection 2021.
High temperature (heat) stress reduces tuber yield and quality of potatoes. Screening potatoes for heat tolerance is increasingly important, considering the climate change scenario and expansion of potatoes to countries where heat stress is an issue. screening for tolerance to abiotic stresses offers several advantages, including quick evaluation of numerous genotypes (clones) in reduced space, controlled environmental conditions (temperature and photoperiod), and free from confounding variables inherent to greenhouse and field conditions. In this study, we explored the feasibility of using a temporary immersion bioreactor system for heat tolerance screening of potatoes. We determined the best hormone-free microtuberizing media for this system (MSG with 8% sucrose) to enhance microtuber number and size. Comparisons of microtubers produced at 30°C as heat treatment, with 16°C as normal condition, allowed to identify heat tolerant and susceptible potato clones. The use of bioreactors allowed distinguishing well-formed (non-deformed) from deformed microtubers. Heat stress increased the total biomass of plant tissues in all the clones. However, the effect of heat stress on microtuber number and weight varied among the clones. Incubation at 30°C decreased the weight and number of non-deformed microtubers in all the clones except for Reveille Russet in which the weight of non-deformed microtubers was significantly increased and the count of non-deformed microtubers was not affected. The potato variety Reveille Russet, which was selected under high-temperature field conditions in Texas, had many non-deformed microtubers per explant and the highest microtuber weight among four clones evaluated under heat stress. We described a faster and reliable microtuberization system for abiotic stress tolerance screening, identified Reveille Russet as a promising heat-tolerant potato variety, and confirmed Russet Burbank and Atlantic as susceptible heat-tolerant checks.
高温（热）胁迫会降低马铃薯的块茎产量和品质。考虑到气候变化情况以及马铃薯种植向存在热胁迫问题的国家扩展，筛选耐热马铃薯变得愈发重要。筛选对非生物胁迫的耐受性具有诸多优势，包括在较小空间内对众多基因型（克隆）进行快速评估、可控的环境条件（温度和光周期），且不受温室和田间条件固有混杂变量的影响。在本研究中，我们探索了使用临时浸没式生物反应器系统进行马铃薯耐热性筛选的可行性。我们确定了该系统用于微块茎形成的最佳无激素培养基（含8%蔗糖的MSG），以增加微块茎的数量和大小。将30°C热处理条件下产生的微块茎与16°C正常条件下产生的微块茎进行比较，从而鉴定出耐热和感热的马铃薯克隆。使用生物反应器能够区分形态良好（未变形）的微块茎和变形的微块茎。热胁迫增加了所有克隆中植物组织的总生物量。然而，热胁迫对微块茎数量和重量的影响因克隆而异。在30°C下培养会减少所有克隆中未变形微块茎的重量和数量，但“雷维尔·鲁塞特”（Reveille Russet）除外，在该品种中，未变形微块茎的重量显著增加，数量未受影响。在得克萨斯州高温田间条件下选育的马铃薯品种“雷维尔·鲁塞特”，在热胁迫下评估的四个克隆中，每个外植体产生的未变形微块茎数量众多，微块茎重量最高。我们描述了一种用于非生物胁迫耐受性筛选的更快且可靠的微块茎形成系统，鉴定出“雷维尔·鲁塞特”是一种有前景的耐热马铃薯品种，并确认“褐皮伯班克”（Russet Burbank）和“大西洋”（Atlantic）作为感热对照品种。
