Ameliorative Effects of Calcium Sprays on Yield and Grain Nutritional Composition of Maize (Zea mays L.) Cultivars under Drought Stress

Abstract

Drought stress is seriously affecting maize production. To investigate the influence of calcium (Ca) foliar application on maize production and chemical composition of grains under drought stress, two experiments were carried out at Cairo University Research Station, Giza, Egypt, during the summer seasons of 2018 and 2019. The experimental design was split-split plot design with a completely randomized blocks arrangement with three replications. Water regimes were assigned to the main plots [100 (control), 75, and 50% of estimated evapotranspiration]. Calcium levels (zero and 50 mg/L) were assigned to the sub plots. Maize cultivars (SC-P3444, Sammaz-35 and EVDT) were assigned to the sub-sub plots. Three maize cultivars were sprayed with Ca solution concentration (50 mg/L) under normal and drought conditions. The control treatment (0 mg/L) was sprayed with an equal amount of distilled water for comparison. Results indicated a significant decrease in total yield and grain characteristics [protein, ash, total sugars, nitrogen (N), phosphorus (P), potassium (K), and iron (Fe) contents] as a response of drought. Calcium foliar application significantly increased maize yield, protein, ash, carbohydrates, starch, total sugars, and ionic contents of grains, except for manganese (Mn), under all irrigation levels. Based on the drought tolerance index (DTI), only cultivar SC-P3444 showed drought tolerance while cultivars Sammaz-35 and EVDT were sensitive to drought stress. Foliar application of Ca on SC-P3444 cultivar achieved the highest grain yield per hectare (8061 kg) under the water regime of 100% of the total evapotranspiration, followed by Sammaz-35 (7570 kg), and EVDT (7191 kg) cultivars. At the water regime of 75% of estimated evapotranspiration (75% irrigation), Ca foliar application increased grain yield by 16, 13 and 14% in SC-P3444, Sammaz-35, and EVDT, respectively. At the water regime of 50% of the estimated evapotranspiration (50% irrigation), Ca foliar application increased grain yield by 17, 16, and 13% in SC-P3444, Sammaz-35, and EVDT, respectively. In brief, Ca had a clear impact on productivity and grain quality with important implications for maize yield under normal and water stress conditions. Our findings demonstrate that foliar application of Ca enabled drought stressed maize plants to survive better under stress. The most water stress tolerant cultivar was SC-P3444 followed by Sammaz-35 and EVDT under drought stress.

Addressing the contribution of small molecule-based biostimulants to the biofortification of maize in a water restriction scenario

“…Therefore, we expected PA supplementation to induce a good CH transport, enhancing the kernel set and the final yield. As a result, WD reduced the CH content compared to the WW conditions in untreated plants, as previously observed by Hussain et al (2020) and Abbas et al (2021) . However, opposite results were also published.…”

“…Low water availability increased the protein content in the flour, as described by Lu et al (2015) ; Barutcular et al (2016) , and Abbas et al (2021) . However, other studies showed no alterations in the protein content by the water restriction ( Hussain et al, 2020 ).…”

“…Only the limitation of water availability has induced controversial results regarding the flour mineral composition. For example, some studies did not see any effect ( Feil et al, 2005 ), whereas others observed a reduction in K, P, and Fe ( Abbas et al, 2021 ). Contrarily, Avila et al (2017) reported the increment of P and Mg on grains of maize plants subjected to water limitations.…”

Role of inorganic and organic ions in response to salt and drought stresses

“…It was indicated that the foliar application of Ca 2+ caused effective shoot growth and distributed fairly more sucrose to the beetroots in response to drought stress (Hosseini et al, 2019). Besides, foliar application of calcium, increase considerably maize yield and ionic contents of grains including N, P, K and Fe which decreased water stress due to the decreased transpiration rate, declined active transport and depressed membrane permeability that results in restriction of nutrient uptake under water deficiency conditions (Abbas et al, 2021). Foliar application of calcium is expected to rise intracellular Ca levels that can stimulate Ca dependent protein kinases and leads to regulating the expression levels of stressresponsive genes through phosphorylate or dephosphorylate specific transcription factors (Reddy et al, 2011).…”

The Physiological Response of Some Cotton Cultivars to Water Stress and Growth Inducers

“…Water deficiency is the main challenge for cotton growth and productivity, especially in arid and semiarid areas worldwide. Drought stress is expected to be more repeated and acute due to global climate change, with harmful impacts on the world's crop production (Abbas et al, 2021). Cotton water requirement is 3000 to 3500m 3 /f during the fall season to obtain a normal yield.…”