Henschel Juliane Maciel, Dantas Estephanni Fernanda Oliveira, de Azevedo Soares Vanessa, Dos Santos Sabrina Kelly, da Silva Gomes Daniel, Ferreira Lucélio Mendes, Lopes Adriano Salviano, Dias Thiago Jardelino, Batista Diego Silva
Programa de Pós-graduação em Agronomia, Universidade Federal da Paraíba, Areia, PB 58397-000 Brazil.
Departamento de Agricultura, Universidade Federal da Paraíba, Campus Universitário III, S/N, Bananeiras, PB 58220-000 Brazil.
Physiol Mol Biol Plants. 2023 Apr;29(4):579-590. doi: 10.1007/s12298-023-01308-6. Epub 2023 Apr 24.
Drought is the major abiotic stress limiting crop production worldwide, with drought events being expected to be harsher and more frequent due to the global warming. In this context, the development of strategies to mitigate the deleterious effects of drought, such as the use of biostimulants, is imperative. Radish is a globally cultivated root vegetable, with high nutritional and phytochemical value. Thus, this study aimed to evaluate the potential of exogenous carnitine application in the mitigation of drought stress on radish morphophysiology. For this, radish plants were grown for 30 days, being irrigated with 80% (well-watered) or 15% (drought stress) of water holding capacity and sprayed with carnitine (5, 50, and 500 µM) or water (0 µM-no carnitine). The experimental design was completely randomized, in a 4 × 2 factorial scheme (carnitine concentrations × water conditions) with six replicates, and each experimental unit consisted of one plant. The gas exchanges, chlorophyll fluorescence, photosynthetic pigments, electrolyte leakage, relative water content, and biomass production and allocation were evaluated. Drought reduced the photosynthetic capacity of plants by impairing water balance and membrane integrity, decreasing biomass accumulation, mainly in globular roots. The application of low carnitine (5 µM) mitigated these negative effects caused by drought, increasing membrane integrity and water balance of plants, while higher carnitine concentration (50 and 500 µM) aggravated drought stress. This study highlights the potential of carnitine in the mitigation of drought stress on radish plants, supporting its role as a biostimulant.
The online version contains supplementary material available at 10.1007/s12298-023-01308-6.
干旱是限制全球作物产量的主要非生物胁迫，由于全球变暖，干旱事件预计将更加严峻和频繁。在此背景下，制定减轻干旱有害影响的策略，如使用生物刺激剂，势在必行。萝卜是一种全球种植的根茎类蔬菜，具有很高的营养价值和植物化学价值。因此，本研究旨在评估外源肉碱对减轻萝卜形态生理干旱胁迫的潜力。为此，萝卜植株生长30天，分别用持水量的80%（充分浇水）或15%（干旱胁迫）进行灌溉，并喷施肉碱（5、50和500 μM）或水（0 μM - 不喷施肉碱）。实验设计采用完全随机的4×2析因方案（肉碱浓度×水分条件），重复6次，每个实验单元由一株植物组成。评估了气体交换、叶绿素荧光、光合色素、电解质渗漏、相对含水量以及生物量生产和分配情况。干旱通过损害水分平衡和膜完整性降低了植物的光合能力，减少了生物量积累，主要是在球形根中。低浓度肉碱（5 μM）的施用减轻了干旱造成的这些负面影响，提高了植物的膜完整性和水分平衡，而较高浓度的肉碱（50和500 μM）则加剧了干旱胁迫。本研究突出了肉碱在减轻萝卜植株干旱胁迫方面的潜力，支持了其作为生物刺激剂的作用。
在线版本包含可在10.1007/s12298 - 023 - 01308 - 6获取的补充材料。
