Laboratory of Plant Breeding, Wageningen University, Wageningen, The Netherlands.
Escuela de Biociencias, Faculta de Ciencias, Universidad Nacional de Colombia- Sede Medellín (UNALMED), Medellín, Colombia.
PLoS One. 2022 Sep 21;17(9):e0273335. doi: 10.1371/journal.pone.0273335. eCollection 2022.
In the last century, Fusarium wilt of banana (FWB) destroyed the banana cultivar Gros Michel. The Cavendish cultivars saved the global banana industry, and currently they dominate global production (50%) and the export trade (95%). However, a new strain called Tropical Race 4 (TR4) surfaced in the late 1960's, spread globally and greatly damages Cavendish plantations as well as manifold local varieties that are primarily grown by small holders. Presently, there is no commercially available replacement for Cavendish and hence control strategies must be developed and implemented to manage FWB. Here, we studied whether it is possible to induce resistance to TR4 by pre-inoculations with different Fusarium spp. Only pre-treatments with an avirulent Race 1 strain significantly reduced disease development of TR4 in a Cavendish genotype and this effect was stable at various nutritional and pH conditions. We then used transcriptome analysis to study the molecular basis of this response. Several genes involved in plant defence responses were up-regulated during the initial stages of individual infections with TR4 and Race 1, as well as in combined treatments. In addition, a number of genes in the ethylene and jasmonate response pathways as well as several gibberellin synthesis associated genes were induced. We observed upregulation of RGA2 like genes in all treatments. Hence, RGA2 could be a key factor involved in both R1 and TR4 resistance. The data support the hypothesis that activating resistance to Race 1 in Cavendish bananas affects TR4 development and provide a first insight of gene expression during the interaction between various Fusarium spp. and banana.
在上个世纪，香蕉枯萎病（FWB）摧毁了香蕉品种 Gros Michel。Cavendish 品种拯救了全球香蕉产业，目前它们主导着全球生产（约 50%）和出口贸易（约 95%）。然而，一种名为热带 4 号小种（TR4）的新菌株在 20 世纪 60 年代后期出现，在全球范围内传播，并严重破坏了 Cavendish 种植园以及主要由小农户种植的多种当地品种。目前，Cavendish 没有商业上可用的替代品，因此必须制定和实施控制策略来管理 FWB。在这里，我们研究了通过预先接种不同的 Fusarium spp. 是否有可能诱导对 TR4 的抗性。只有用无毒力的 Race 1 菌株进行预处理才能显著降低 Cavendish 基因型中 TR4 的病害发展，这种效应在各种营养和 pH 条件下都是稳定的。然后，我们使用转录组分析来研究这种反应的分子基础。在 TR4 和 Race 1 的单独感染以及联合处理的初始阶段，有几个参与植物防御反应的基因上调。此外，乙烯和茉莉酸响应途径以及一些与赤霉素合成相关的基因也被诱导。我们观察到所有处理中 RGA2 样基因的上调。因此，RGA2 可能是参与 R1 和 TR4 抗性的关键因素。这些数据支持了这样一种假设，即激活 Cavendish 香蕉对 Race 1 的抗性会影响 TR4 的发展，并提供了在各种 Fusarium spp.和香蕉相互作用过程中基因表达的初步见解。
