Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands.
Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands.
J Integr Plant Biol. 2019 May;61(5):624-638. doi: 10.1111/jipb.12788. Epub 2019 Mar 28.
Many economically important perennial species bear recalcitrant seeds, including tea, coffee, cocoa, mango, citrus, rubber, oil palm and coconut. Orthodox seeds can be dried almost completely without losing viability, but so-called recalcitrant seeds have a very limited storage life and die upon drying below a higher critical moisture content than orthodox seeds. As a result, the development of long-term storage methods for recalcitrant seeds is compromised. Lowering this critical moisture content would be very valuable since dry seed storage is the safest, most convenient and cheapest method for conserving plant genetic resources. Therefore, we have attempted to induce desiccation tolerance (DT) in the desiccation sensitive seeds of Citrus limon. We show that DT can be induced by paclobutrazol (an inhibitor of gibberellin biosynthesis) and we studied its associated transcriptome to delineate the molecular mechanisms underlying this induction of DT. Paclobutrazol not only interfered with gibberellin related gene expression but also caused extensive changes in expression of genes involved in the biosynthesis and signaling of other hormones. Paclobutrazol induced a transcriptomic switch encompassing suppression of biotic- and induction of abiotic responses. We hypothesize that this is the main driver of the induction of DT by paclobutrazol in C. limon seeds.
许多具有经济重要性的多年生物种具有顽拗性种子，包括茶、咖啡、可可、芒果、柑橘、橡胶、油棕和椰子。正统种子可以在几乎完全干燥的情况下而不丧失活力，但是所谓的顽拗性种子的储存寿命非常有限，在低于正统种子的临界水分含量时就会死亡。因此，开发顽拗性种子的长期储存方法受到了影响。降低这个临界水分含量将非常有价值，因为干燥种子储存是保存植物遗传资源最安全、最方便和最便宜的方法。因此，我们试图在敏感的柠檬种子中诱导耐旱性（DT）。我们发现，通过多效唑（一种赤霉素生物合成抑制剂）可以诱导 DT，并且我们研究了其相关的转录组，以描绘这种 DT 诱导的分子机制。多效唑不仅干扰了赤霉素相关基因的表达，而且还导致了参与其他激素生物合成和信号转导的基因的广泛变化。多效唑诱导了一个转录组开关，包括对生物胁迫的抑制和对非生物胁迫的诱导。我们假设这是多效唑在柠檬种子中诱导 DT 的主要驱动因素。
