Synergistic Effect of Selenium Addition and Water Stress on <i>Melilotus officinalis</i> L. Mineral Content

Abstract

The objective of this study was to examine the combined effects of selenium (Se) enrichment and water stress on the accumulation of available macro-and micronutrients in Melilotus officinalis L. aerial parts. Plants of M. officinalis were subjected to three levels of Se addition (0, 1 and 3 mg Se L -1 water) and to two water treatments: a) full irrigation and b) limited irrigation (water stress). The above ground biomass (stems and leaves) was analyzed for Se, potassium (K), sodium (Na), magnesium (Mg), iron (Fe), copper (Cu), calcium (Ca), manganese (Mn) and zinc (Zn). Se addition differentially affected the K, Mg and Ca content of M. officinalis aerial parts, while it led to the reduction of the micronutrients Cu, Fe and Mn. Water stress resulted in the increase of K, Na, Mg, Ca and Cu, and to the decrease of the Fe, Zn and Mn content. An interaction between selenium addition and water treatment was more notable for Ca and Mg, which decreased under water stress at low Se level and for Zn and Cu, which increased under water stress at high Se level. According to our findings, Seinduced increased accumulation of some inorganic ions in the aerial parts of this species under water stress conditions could serve as a means to alleviate the adverse impact of water deficit on important metabolic processes, enhancing M. officinalis tolerance to water stress.

Effect of Selenite and Selenate Application on Mineral Composition of Lettuce Plants Cultivated Under Hydroponic Conditions: Nutritional Balance Overview Using a Multifaceted Study

“…In general, these results are in agreement with the assumption that the absorption of micronutrients tends to be inhibited by increasing selenate and selenite levels, 14,32,51,56 although Ríos et al 25 had found that the Fe concentration increased in the selenized lettuce.…”

“…For example, the uptake of K by plant cells, and its accumulation in vacuoles, is the primary driver for their osmotic expansion, and the plant transpiration is a very important issue for Ca and Mg concentration. 26,[55][56][57] In this study, lettuce plants were cultivated in a very dry period and in a year that the temperatures reached record highs (38 °C in the cultivation period out and 43 °C inside of the greenhouse). Because of this the high rate of plant transpiration had affected the accumulation of the elements for the lettuce cultivar studied in the present work.…”