Kobayashi Yasufumi, Sugita Ryohei, Fujita Miki, Yasui Yasuo, Murata Yoshinori, Ogata Takuya, Nagatoshi Yukari, Fujita Yasunari
Biological Resources and Post-harvest Division, Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki, Japan.
Radioisotope Research Center, Nagoya University, Nagoya, Aichi, Japan.
Front Plant Sci. 2025 Jun 18;16:1597647. doi: 10.3389/fpls.2025.1597647. eCollection 2025.
Salinity threatens crop production worldwide, and salinized areas are steadily increasing. As most crops are sensitive to salt, there is a need to improve the salt tolerance of major crops and promote the cultivation of under-utilized salt-tolerant crops. Quinoa, a pseudocereal and leafy vegetable from the Andean region of South America, is highly salt-tolerant, thrives in marginal environments, and has excellent nutritional properties. Research has often focused on epidermal bladder cells, a feature of quinoa thought to contribute to salt tolerance; however, recent evidence suggests that these cells are not directly involved. The salt tolerance mechanism in quinoa remains unclear. Here, we show genotype-dependent differences in Na and K accumulation mechanisms using representative 18 lines of three genotypes by focusing on young quinoa seedlings at a stage without epidermal bladder cells. High salinity (600 mM NaCl) did not affect the early growth of all three quinoa genotypes. Under high salinity conditions, lowland quinoa lines tended to accumulate more Na in their aerial parts than highland lines did. By contrast, K accumulation was slightly reduced in the aerial parts but significantly decreased in the roots of all the genotypes. Resequencing of 18 quinoa lines supports the notion that genotype determines aboveground Na uptake and gene expression in response to high salinity. Using virus-induced gene silencing, we further demonstrated that CqHKT1 and CqSOS1 mediate Na exclusion in quinoa. These findings provide insight into salt tolerance mechanisms, serving as a basis for improving crop production under high salinity conditions.
盐度威胁着全球的作物生产，盐碱化地区正在稳步增加。由于大多数作物对盐敏感，因此需要提高主要作物的耐盐性，并推广未充分利用的耐盐作物的种植。藜麦是一种来自南美洲安第斯地区的假谷物和叶菜类蔬菜，具有高度耐盐性，能在边缘环境中茁壮成长，且具有优良的营养特性。研究通常集中在藜麦的表皮泡状细胞上，认为这一特征有助于耐盐性；然而，最近的证据表明这些细胞并不直接参与其中。藜麦的耐盐机制仍不清楚。在这里，我们通过聚焦于没有表皮泡状细胞阶段的藜麦苗，使用三种基因型的18个代表性品系，展示了钠和钾积累机制的基因型依赖性差异。高盐度（600 mM NaCl）并未影响所有三种藜麦基因型的早期生长。在高盐条件下，低地藜麦品系地上部分积累的钠往往比高地品系更多。相比之下，所有基因型地上部分的钾积累略有减少，但根部的钾积累显著下降。对18个藜麦品系的重测序支持了基因型决定地上部分钠吸收和对高盐度响应的基因表达这一观点。利用病毒诱导的基因沉默，我们进一步证明了CqHKT1和CqSOS1介导藜麦中的钠外排。这些发现为耐盐机制提供了见解，为改善高盐条件下的作物生产奠定了基础。
