Guillamón Jesús Guillamón, Dicenta Federico, Sánchez-Pérez Raquel
Department of Plant Breeding, CEBAS-CSIC, Campus Universitario de Espinardo, Espinardo, Spain.
Front Plant Sci. 2022 Jan 14;12:812621. doi: 10.3389/fpls.2021.812621. eCollection 2021.
Endodormancy in temperate fruit trees like is a protector state that allows the trees to survive in the adverse conditions of autumn and winter. During this process, plants accumulate chill hours. Flower buds require a certain number of chill hours to release from endodormancy, known as chilling requirements. This step is crucial for proper flowering and fruit set, since incomplete fulfillment of the chilling requirements produces asynchronous flowering, resulting in low quality flowers, and fruits. In recent decades, global warming has endangered this chill accumulation. Because of this fact, many agrochemicals have been used to promote endodormancy release. One of the first and most efficient agrochemicals used for this purpose was hydrogen cyanamide. The application of this agrochemical has been found to advance endodormancy release and synchronize flowering time, compressing the flowering period and increasing production in many species, including apple, grapevine, kiwi, and peach. However, some studies have pointed to the toxicity of this agrochemical. Therefore, other non-toxic agrochemicals have been used in recent years. Among them, Erger + Activ Erger and Syncron + NitroActive have been the most popular alternatives. These two treatments have been shown to efficiently advance endodormancy release in most of the species in which they have been applied. In addition, other less popular agrochemicals have also been applied, but their efficiency is still unclear. In recent years, several studies have focused on the biochemical and genetic variation produced by these treatments, and significant variations have been observed in reactive oxygen species, abscisic acid (ABA), and gibberellin (GA) levels and in the genes responsible for their biosynthesis. Given the importance of this topic, future studies should focus on the discovery and development of new environmentally friendly agrochemicals for improving the modulation of endodormancy release and look more deeply into the effects of these treatments in plants.
像温带果树中的内休眠是一种保护状态，使树木能够在秋冬的不利条件下存活。在此过程中，植物积累需冷时数。花芽需要一定数量的需冷时数才能从内休眠中解除，这称为需冷量。这一步骤对于正常开花和坐果至关重要，因为需冷量未完全满足会导致开花不同步，从而产生低质量的花朵和果实。近几十年来，全球变暖危及了这种需冷量的积累。因此，人们使用了许多农用化学品来促进内休眠的解除。用于此目的的最早且最有效的农用化学品之一是氰胺。已发现施用这种农用化学品可提前解除内休眠并使开花时间同步，缩短花期并提高包括苹果、葡萄、猕猴桃和桃子在内的许多物种的产量。然而，一些研究指出了这种农用化学品的毒性。因此，近年来人们使用了其他无毒农用化学品。其中，Erger + Activ Erger和Syncron + NitroActive是最受欢迎的替代品。这两种处理方法已被证明能在大多数已应用的物种中有效提前解除内休眠。此外，还应用了其他不太受欢迎的农用化学品，但其效果仍不明确。近年来，一些研究集中在这些处理方法所产生的生化和遗传变异上，并且在活性氧、脱落酸（ABA）和赤霉素（GA）水平以及负责其生物合成的基因中观察到了显著变异。鉴于该主题的重要性，未来的研究应专注于发现和开发新的环保农用化学品，以改善对内休眠解除的调控，并更深入地研究这些处理方法对植物的影响。
