Department of Plant Pathology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
Department of Biotechnology, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium.
BMC Plant Biol. 2020 Oct 22;20(1):483. doi: 10.1186/s12870-020-02706-8.
Sugar beet (Beta vulgaris subsp. vulgaris) is an economically important crop that provides nearly one third of the global sugar production. The beet cyst nematode (BCN), Heterodera schachtii, causes major yield losses in sugar beet and other crops worldwide. The most effective and economic approach to control this nematode is growing tolerant or resistant cultivars. To identify candidate genes involved in susceptibility and resistance, the transcriptome of sugar beet and BCN in compatible and incompatible interactions at two time points was studied using mRNA-seq.
In the susceptible cultivar, most defense-related genes were induced at 4 dai while suppressed at 10 dai but in the resistant cultivar Nemakill, induction of genes involved in the plant defense response was observed at both time points. In the compatible interaction, alterations in phytohormone-related genes were detected. The effect of exogenous application of Methyl Jasmonate and ET-generator ethephon on susceptible plants was therefore investigated and the results revealed significant reduction in plant susceptibility. Genes putatively involved in the resistance of Nemakill were identified, such as genes involved in phenylpropanoid pathway and genes encoding CYSTM domain-containing proteins, F-box proteins, chitinase, galactono-1,4-lactone dehydrogenase and CASP-like protein. Also, the transcriptome of the BCN was analyzed in infected root samples and several novel potential nematode effector genes were found.
Our data provides detailed insights into the plant and nematode transcriptional changes occurring during compatible and incompatible interactions between sugar beet and BCN. Many important genes playing potential roles in susceptibility or resistance of sugar beet against BCN, as well as some BCN effectors with a potential role as avr proteins were identified. In addition, our findings indicate the effective role of jasmonate and ethylene in enhancing sugar beet defense response against BCN. This research provides new molecular insights into the plant-nematode interactions that can be used to design novel management strategies against BCN.
糖甜菜（Beta vulgaris subsp. vulgaris）是一种经济上重要的作物，提供了全球糖产量的近三分之一。甜菜胞囊线虫（BCN）， Heterodera schachtii，在全球范围内导致甜菜和其他作物的重大产量损失。控制这种线虫最有效和经济的方法是种植耐受或抗性品种。为了鉴定参与敏感性和抗性的候选基因，使用 mRNA-seq 研究了在两个时间点甜菜与 BCN 相容和不相容互作中的转录组。
在易感品种中，大多数防御相关基因在 4 天诱导，而在 10 天抑制，但在抗性品种 Nemakill 中，观察到参与植物防御反应的基因在两个时间点都被诱导。在相容互作中，检测到植物激素相关基因的变化。因此，研究了外源施用茉莉酸甲酯和 ET 发生器乙膦对易感植物的影响，结果表明植物的易感性显著降低。鉴定了Nemakill 抗性中涉及的推定基因，如苯丙烷途径相关基因和编码 CYSTM 结构域蛋白、F-box 蛋白、几丁质酶、半乳糖酸-1,4-内酯脱氢酶和 CASP 样蛋白的基因。此外，还分析了感染根样本中的 BCN 转录组，发现了几个新的潜在线虫效应基因。
我们的数据提供了在甜菜与 BCN 之间的相容和不相容互作过程中植物和线虫转录变化的详细见解。鉴定了许多在甜菜对 BCN 的敏感性或抗性中发挥潜在作用的重要基因，以及一些可能作为 avr 蛋白发挥作用的 BCN 效应子。此外，我们的发现表明茉莉酸和乙烯在增强甜菜对 BCN 的防御反应中的有效作用。这项研究为植物-线虫相互作用提供了新的分子见解，可用于设计针对 BCN 的新管理策略。
