Exogenously Used 24-Epibrassinolide Promotes Drought Tolerance in Maize Hybrids by Improving Plant and Water Productivity in an Arid Environment

Abstract

The influence of 24-epibrassinolide (EBR24), applied to leaves at a concentration of 5 μM, on plant physio-biochemistry and its reflection on crop water productivity (CWP) and other agronomic traits of six maize hybrids was field-evaluated under semi-arid conditions. Two levels of irrigation water deficiency (IWD) (moderate and severe droughts; 6000 and 3000 m3 water ha–1, respectively) were applied versus a control (well-watering; 9000 m3 water ha–1). IWD reduced the relative water content, membrane stability index, photosynthetic efficiency, stomatal conductance, and rates of transpiration and net photosynthesis. Conversely, antioxidant enzyme activities and osmolyte contents were significantly increased as a result of the increased malondialdehyde content and electrolyte leakage compared to the control. These negative influences of IWD led to a reduction in CWP and grain yield-related traits. However, EBR24 detoxified the IWD stress effects and enhanced all the above-mentioned parameters. The evaluated hybrids varied in drought tolerance; Giza-168 was the best under moderate drought, while Fine-276 was the best under severe drought. Under IWD, certain physiological traits exhibited a highly positive association with yield and yield-contributing traits or CWP. Thus, exogenously using EBR24 for these hybrids could be an effective approach to improve plant and water productivity under reduced available water in semi-arid environments.

Exogenous Gibberellic Acid or Dilute Bee Honey Boosts Drought Stress Tolerance in Vicia faba by Rebalancing Osmoprotectants, Antioxidants, Nutrients, and Phytohormones

“…Finally, the negative effects of environmental foes may exceed the natural endurance of stressed plants. In this case, the components of a stressed plant's defense system do not meet adequate defense requirements, and therefore external use of auxiliary substances such as nutrients and other beneficial strategies increases the efficiency of antioxidant defenses, and thus plants can perform efficiently under adverse conditions of environmental foes [61][62][63][64][65].…”

Foliar Nourishment with Nano-Selenium Dioxide Promotes Physiology, Biochemistry, Antioxidant Defenses, and Salt Tolerance in Phaseolus vulgaris

“…However, under severe stress, the natural tolerance of plants does not help with stress resistance since the active ingredients of the plant with low-molecular mass and high-molecular mass do not provide sufficient requirements for defense against stress. Therefore, exogenous adjuvants, including beneficial nutrients in nanoparticles and other auxiliary strategies, must be used to raise the efficiency of antioxidant defense in stressed plants to enable them to function effectively under different stresses [7,10,[54][55][56][57][58][59], including salinity [6,[60][61][62].…”

Revitalizing Fertility of Nutrient-Deficient Virgin Sandy Soil Using Leguminous Biocompost Boosts Phaseolus vulgaris Performance

“…Furthermore, the accumulation of ascorbate and glutathione with the S CF75 + F CF25 + C L B treatment contributed to the improved tissue water status and membrane integrity by reducing the activity of the reactive oxygen species (ROS) [ 47 , 92 , 93 ]. It has been explained that the accumulation of K + , free proline, and soluble sugars as osmolytes contributes to osmotic adjustment, which helps to maintain the cell turgor and stabilize the membranes by activation of antioxidant plant defense system [ 73 , 94 , 95 , 96 , 97 , 98 , 99 ]. This is also evident from improvement in antioxidant enzymes activities in this study ( Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 and Figure 12 ), such as superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (GPOD), including leaf content of protein for the S CF75 + F CF25 + C L B treatment in P. vulgaris plants grown under the tested conditions.…”