Photosynthetic capacity, nutrient status, and growth of maize (Zea mays L.) upon MgSO4 leaf-application

Abstract

The major plant nutrient magnesium (Mg) is involved in numerous physiological processes and its deficiency can severely reduce the yield and quality of crops. Since Mg availability in soil and uptake into the plant is often limited by unfavorable soil or climatic conditions, application of Mg onto leaves, the site with highest physiological Mg demand, might be a reasonable alternative fertilization strategy. This study aimed to investigate, if MgSO4 leaf-application in practically relevant amounts can efficiently alleviate the effects of Mg starvation in maize, namely reduced photosynthesis capacity, disturbed ion homeostasis and growth depression. Results clearly demonstrated that Mg deficiency could be mitigated by MgSO4 leaf-application as efficiently as by resupply of MgSO4 via the roots in vegetative maize plants. Significant increases in SPAD values and net rate of CO2-assimilation as well as enhanced shoot biomass have been achieved. Ion analysis furthermore revealed an improvement of the nutrient status of Mg-deficient plants with regard to [Mg], [K], and [Mn] in distinct organs, thereby reducing the risk of Mn-toxicity at the rootside, which often occurs together with Mg deficiency on acid soils. In conclusion, foliar fertilization with Mg proved to be an efficient strategy to adequately supply maize plants with Mg and might hence be of practical relevance to correct nutrient deficiencies during the growing season.

Magnesium deficiency decreases biomass water-use efficiency and increases leaf water-use efficiency and oxidative stress in barley plants

“…Similarly, Terry and Ulrich (1974) reported a rapid decline in A N due to Mg deficiency in sugar beet already 7 DAO. Similar results were obtained in studies on Pinus (Laing et al 2000;Sun et al 2001), citrus (Tang et al 2012;Yang et al 2012), sugar beet (Terry and Ulrich 1974) and maize (Jezek et al 2015). Tang et al (2012) proposed nonstomatal reasons for a decrease in A N in citrus, as the internal CO 2 concentration did not differ from that of plants supplied with adequate amounts of Mg.…”

Glutamine synthetase activity in leaves of Zea mays L. as influenced by magnesium status

“…The finding that a severe Mg deficiency of 54 days, as induced by only 0.01 mM MgSO 4 in the NS, does not compromise both, the in vitro GS activity and its abundance in leaves, appears unexpected not only because Mg is an indispensable component for the structural integrity and activity of the enzyme. Moreover, former studies showed strong reductions in CO 2 fixation, chlorophyll concentrations, and overall growth of maize under such a severe Mg deficiency (Jezek et al 2015). The results of the present study strongly indicate that the GS- In this study, higher total GS activities were measured when plants were resupplied with Mg over the leaves after 27 days of Mg starvation (Fig.…”

Yield performance of soybean and corn subjected to magnesium foliar spray

“…Foliar nutrient application can be a good strategy to increase crop yield, help in soil supplementation, and generate response in a short period of time (Fageria et al, 2009). Jezek et al (2015) observed an increased leaf Mg content, SPAD index, photosynthetic rate, and accumulation of shoot biomass in corn (Zea mays) subjected to a foliar spray of Mg under controlled conditions. Positive effects on crop yield from spraying foliage with Mg were observed in sugar beet (Beta vulgaris L.) (Barlog & Grzebisz, 2001), soybean (Glycine max) (Vrataric et al, 2006), and fava bean (Vicia faba) (Neuhaus et al, 2014).…”