Application of Magnesium and Calcium Sulfate on Growth and Physiology of Forage Crops under Long-Term Salinity Stress

Abstract

Soil salinity is major threat to crop growth and reducing cultivated land areas and salt-resistant crops have been required to sustain agriculture in salinized areas. This original research was performed to determine the effectiveness of MgSO4 (MS) and CaSO4 (CS) for each species and assess changes in the physiology and growth of fodder crops after short and long-term salt stress. Six treatments (CON (control); NaCl (NaCl 100 mM); 1 MS (1 mM MgSO4 + 100 mM NaCl); 2 MS (2 mM MgSO4 + 100 mM NaCl); 7.5 CS (7.5 mM CaSO4 + 100 mM NaCl); and 10 CS (10 mM CaSO4 + 100 mM NaCl)) were applied to Red clover (Trifolium pratense) and Tall fescue (Festuca arundinacea) under greenhouse conditions. Cultivars were evaluated based on their dry weights, physiological parameters, forage quality, and ion concentrations. The biomass of both species decreased significantly under NaCl treatments and increased under the MS and CS treatments compared to solely salinity treatments. Salinity caused a decrease in the photosynthetic rate, but compared to CON, the MS and CS treatments yielded superior results. Moreover, the Na+/K+ ratio increased as Na+ concentration increased but crop quality (CP, NDF, ADF) did not show significant differences under salinity. Overall, we concluded that these T. pratense and F. arundinacea species demonstrated various responses to salinity, MS, and CS by different physiological and morphological parameters and it turned out to be efficient under salinity stress.

Evaluating the Effects of Long-Term Salinity Stress on the Growth and Physiology of Mono and Mixed Crops

“…Our previous study was focused on the effect of calcium and magnesium sulfate on monocrops under various salinity stresses [14]. Further, the purpose of the present study was to investigate changes in physiology and growth of the mono forage crops by exposing them to various salinity concentrations and then observing whether the salt tolerance of forage crops could improve through the application of magnesium and calcium sulfate fertilizers in mixed cropping.…”

“…Red clover (Trifolium pratense L.) is an essential grassland forage crop across temperate regions, regularly used in cycles with yearly crops or re-sown meadows, offering high yields, symbiotic N fixation, good soil structure, and high-quality animal feed [13]. Moreover, compared to the other legumes, red clover has a slower rate of protein degradation during ensiling, thus making it an excellent feed for grazing livestock [14]. The high protein content, digestibility, and quality of the milk produced by livestock that consume alfalfa make Alfalfa (Medicago sativa L.) a highly valued cash crop, one that is primarily used as livestock feed [15].…”

“…However, it was established that environmental impact can differ greatly between plant species and soil conditions depending on salinity levels and duration [19]. In this, recent studies and our previous studies suggest that certain agricultural practices such as mixed cropping and the additional application of fertilizers alleviate the effects of salinity stress on crop productivity [14,20,21]. Mixed cropping, also known as intercropping, is a traditional method that involves planting multiple crop varieties in one area simultaneously [22].…”