García-Jiménez Atonaltzin, Gómez-Merino Fernando C, Tejeda-Sartorius Olga, Trejo-Téllez Libia I
Plant Physiology, Colegio de Postgraduados Campus Montecillo Montecillo, Mexico.
Biotechnology, Colegio de Postgraduados Campus Córdoba Veracruz, Mexico.
Front Plant Sci. 2017 Mar 10;8:308. doi: 10.3389/fpls.2017.00308. eCollection 2017.
Lanthanum (La) is considered a beneficial element, capable of inducing hormesis. Hormesis is a dose-response relationship phenomenon characterized by low-dose stimulation and high-dose inhibition. Herein we tested the effect of 0 and 10 μM La on growth and biomolecule concentrations of seedlings of four sweet bell pepper ( L.) varieties, namely Sven, Sympathy, Yolo Wonder, and Zidenka. Seedling evaluations were performed 15 and 30 days after treatment applications (dat) under hydroponic greenhouse conditions. Seedling height was significantly increased by La, growing 20% taller in Yolo Wonder plants, in comparison to the control. Similarly, La significantly enhanced shoot diameter, with increases of 9 and 9.8% in measurements performed 15 and 30 dat, respectively, as compared to the control. Likewise, La-treated seedlings had a higher number of flower buds than the control. An increase in the number of leaves because of La application was observed in Yolo Wonder seedlings, both 15 and 30 dat, while leaf area was augmented in this variety only 30 dat. Nevertheless, La did not affect dry biomass accumulation. La effects on biomolecule concentration were differential over time. In all varieties, La stimulated the biosynthesis of chlorophyll and total 15 dat, though 30 dat only the varieties Sympathy and Yolo Wonder showed enhanced concentrations of these molecules because of La. Total soluble sugars increased in La-treated seedlings 30 dat. Interestingly, while most varieties exposed to La showed a reduction in amino acid concentration 15 dat, the opposite trend was observed 30 dat. Importantly, in all varieties evaluated, La stimulated soluble protein concentration 30 dat. It is important to note that while chlorophyll concentrations increased in all varieties exposed to La, both 15 and 30 dat, those of soluble sugars and proteins consistently increased only 30 dat, but not 15 dat. Our results confirm that La may improve seedling quality by enhancing some growth parameters and biomolecule concentrations, depending on the genotype, and time of exposure.
镧（La）被认为是一种有益元素，能够引发兴奋效应。兴奋效应是一种剂量 - 反应关系现象，其特征为低剂量刺激和高剂量抑制。在此，我们测试了0和10μM镧对四个甜椒（L.）品种，即斯文（Sven）、同情（Sympathy）、约洛奇迹（Yolo Wonder）和齐登卡（Zidenka）幼苗生长及生物分子浓度的影响。在水培温室条件下，于处理应用后15天和30天（dat）进行幼苗评估。与对照相比，镧显著增加了幼苗高度，约洛奇迹植株的高度比对照高20%。同样，镧显著增加了茎直径，在处理后15天和30天进行的测量中，分别比对照增加了9%和9.8%。同样，经镧处理的幼苗比对照有更多的花芽。在约洛奇迹幼苗中，处理后15天和30天均观察到因施用镧而使叶片数量增加，而该品种仅在处理后30天叶片面积增大。然而，镧并不影响干生物量积累。镧对生物分子浓度的影响随时间而异。在所有品种中，处理后15天镧刺激了叶绿素和总[此处原文可能缺失部分内容]的生物合成，不过处理后30天，只有同情和约洛奇迹品种因镧而这些分子的浓度有所增加。处理后30天，经镧处理的幼苗中总可溶性糖增加。有趣的是，虽然大多数暴露于镧的品种在处理后15天氨基酸浓度降低，但在处理后30天观察到相反的趋势。重要的是，在所有评估品种中，处理后30天镧刺激了可溶性蛋白质浓度增加。需要注意的是，虽然所有暴露于镧的品种在处理后15天和30天叶绿素浓度均增加，但可溶性糖和蛋白质的浓度仅在处理后30天持续增加，而在处理后15天没有增加。我们的结果证实，镧可能通过增强一些生长参数和生物分子浓度来提高幼苗质量，这取决于基因型和暴露时间。
