Department of Biologia Aplicada à Agropecuária, Universidade Estadual Paulista 'Julio de Mesquita Filho', 14884-900 Jaboticabal, SP, Brasil; and CSIRO Agriculture and Food, GPO Box 1700, Canberra, ACT 2601, Australia.
Department of Tecnologia, Universidade Estadual Paulista 'Julio de Mesquita Filho', 14884-900 Jaboticabal, SP, Brasil.
Funct Plant Biol. 2021 May;48(6):588-596. doi: 10.1071/FP20314.
Soil salinity affects sugarcane (Saccharum officinale L.) production in arid and semiarid climates, severely reducing productivity. This study aimed to identify differentially regulated proteins in two cultivars that differ markedly in tolerance of saline soil. Plants were grown for 30 days and then subjected to treatments of 0 and 160 mM NaCl for 15 days. The tolerant cultivar showed a 3-fold upregulation of lipid metabolising enzymes, GDSL-motif lipases, which are associated with defence to abiotic stress, and which were not upregulated in the sensitive cultivar. Lipoxygenase was 2-fold upregulated in the tolerant cultivar but not in the sensitive cultivar, as were Type III chlorophyll a/b binding proteins. Other differences were that in the sensitive cultivar, the key enzyme of C4 photosynthesis, phosphoenolpyruvate carboxylase was downregulated, along with other chloroplast enzymes. Na+ concentrations had not reached toxic concentrations in either cultivar by this time of exposure to salt, so these changes would be in response to the osmotic effect of the soil salinity, and likely be in common with plants undergoing drought stress.
土壤盐度会影响干旱和半干旱气候下的甘蔗（Saccharum officinale L.）生产，严重降低生产力。本研究旨在鉴定两个品种中差异调节的蛋白质，这两个品种在耐盐土壤方面差异明显。将植物种植 30 天，然后用 0 和 160 mM NaCl 处理 15 天。耐盐品种中脂质代谢酶、GDSL 基序脂肪酶的表达上调了 3 倍，这些酶与非生物胁迫防御有关，而在敏感品种中则没有上调。脂氧合酶在耐盐品种中上调了 2 倍，但在敏感品种中没有上调，III 型叶绿素 a/b 结合蛋白也是如此。其他差异是，在敏感品种中，C4 光合作用的关键酶磷酸烯醇丙酮酸羧激酶下调，同时还下调了其他叶绿体酶。到此时，暴露在盐中，两个品种的钠离子浓度都没有达到毒性浓度，因此这些变化将是对土壤盐度渗透效应的响应，并且可能与经历干旱胁迫的植物相同。
