Jakovljević Dragana, Momčilović Jovana, Bojović Biljana, Stanković Milan
Department of Biology and Ecology, Faculty of Science, University of Kragujevac, 34 000 Kragujevac, Serbia.
Plants (Basel). 2021 Mar 21;10(3):590. doi: 10.3390/plants10030590.
Chilling stress in spring and mid-season heat stress are important environmental stresses that can significantly affect plant productivity. The objectives of this study were to understand the effects of cold (4 and 10 °C) or heat (30 and 40 °C) stress on biochemical and physiological traits in leaves and roots of basil ( L. cv. 'Genovese') young plants. After short-time exposure to mild and severe temperature stresses, both photosynthetic pigments' and protein, as well as enzymatic and non-enzymatic defense components in basil leaves and roots, were quantified and compared with the control non-stressed plants. It was shown that both cold and heat treatment increase the content of chlorophyll , chlorophyll , and carotenoids. Chilling correlated with higher content of soluble proteins in leaves, whereas the concentration of these osmoprotectants in roots was higher under both cold and heat stress. For all tested antioxidant enzymes, higher activity was measured in leaves, and activity was related to temperature stress. SOD, CAT, A-POX, and P-POX activities was induced under heat stress, while the higher activity of SOD, CAT, P-POX, and G-POX was recorded under cold stress, compared to the control. In addition to the induced activity of enzymatic components, the content of secondary metabolites including total phenolics, flavonoids, and total anthocyanins, was several times higher compared to the non-stressed plants. Furthermore, total phenolic content was higher in roots than in leaves. Significant positive correlation can be seen among photosynthetic pigments, SOD, total phenolics, and flavonoids under severe temperature stress (4 or 40 °C) in basil leaves, while for roots, positive correlation was found in the content of secondary metabolites and activity of CAT or peroxidases. Obtained results are discussed in terms of phenotyping of cv. 'Genovese' response to heat and chilling stress, which should contribute to a better understanding of merged responses to cold and heat tolerance of this valuable crop.
春季的低温胁迫和生育中期的热胁迫是重要的环境胁迫，会显著影响植物生产力。本研究的目的是了解冷胁迫（4℃和10℃）或热胁迫（30℃和40℃）对罗勒（L. cv. 'Genovese'）幼苗叶片和根系生化及生理特性的影响。在短期暴露于轻度和重度温度胁迫后，对罗勒叶片和根系中的光合色素、蛋白质以及酶促和非酶促防御成分进行了定量分析，并与未受胁迫的对照植株进行了比较。结果表明，冷处理和热处理均增加了叶绿素a、叶绿素b和类胡萝卜素的含量。低温胁迫与叶片中可溶性蛋白质含量较高相关，而在冷胁迫和热胁迫下，这些渗透保护剂在根系中的浓度均较高。对于所有测试的抗氧化酶，叶片中的活性较高，且活性与温度胁迫有关。与对照相比，热胁迫下超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（A-POX）和愈创木酚过氧化物酶（P-POX）的活性被诱导，而冷胁迫下SOD、CAT、P-POX和谷胱甘肽过氧化物酶（G-POX）的活性更高。除了酶促成分的诱导活性外，包括总酚、黄酮类化合物和总花青素在内的次生代谢物含量比未受胁迫的植株高出数倍。此外，根系中的总酚含量高于叶片。在罗勒叶片受到重度温度胁迫（4℃或40℃）时，光合色素、SOD、总酚和黄酮类化合物之间存在显著正相关，而对于根系，次生代谢物含量与CAT或过氧化物酶活性之间存在正相关。从'Genovese'品种对热胁迫和冷胁迫的表型分析角度对所得结果进行了讨论，这有助于更好地理解这种重要作物对冷热耐受性的综合反应。
