Enhancing Drought Tolerance and Water Productivity of Diverse Maize Hybrids (Zea mays) Using Exogenously Applied Biostimulants under Varying Irrigation Levels

Abstract

Water deficit is a decisive challenge that tremendously affects maize physiological functions and productivity. Hence, it is crucial to ameliorate its tolerance to drought stress, in particular under abrupt climate change and a growing population. The present study aimed to explore the influence of exogenously sprayed moringa seed extract (Moringa oleifera) and α-tocopherol on physio-biochemical, morphological, and yield attributes of six diverse maize hybrids under three irrigation levels in poor-fertility sandy soil. The applied irrigation regimes were based on estimated crop evapotranspiration (ET) using the FAO Penman–Monteith equation. A split–split plot arrangement with a randomized complete block design and three replicates was applied for different treatments. Irrigation levels (100% ET, 75% ET and 50% ET) were established in the main plots, while foliar applications (moringa extract and α-tocopherol) were located in subplots and the assessed hybrids (SC162, SC166, SC167, SC168, SC176, and SC178) in subsubplots. Mild (75% ET) and severe (50% ET) drought stress gradually reduced the gas exchange, photosynthetic efficiency, water relations, and yield traits compared with well-watered conditions (100% ET). However, foliar application of moringa seed extract or α-tocopherol was effective in reinforcing maize tolerance to drought stress by enhancing the accumulation of osmoprotectants, improving antioxidant enzymes, and decreasing levels of peroxidation of membrane lipids and electrolyte leakage compared to untreated control. These positive impacts were reflected in boosting yield traits and crop water productivity under water deficit conditions. The physiological and agronomic performance of the assessed maize hybrids considerably varied under water deficit conditions. The hybrids SC168, SC176, and SC178 exhibited the best performance under mild and severe drought conditions compared with the other hybrids. Consequently, the integration of exogenously applied moringa seed extract or α-tocopherol with tolerant maize hybrids such as SC168, SC176, and SC178 is an efficient approach to ameliorating drought tolerance under water-scarce conditions in arid environments.

Influence of Foliar Supplied of Some Biostimulants on Physiological, Agronomic Characters and Water Productivity of Rice Under Water Deficit and Normal Conditions

“…Drought is a significant environmental stress that has adverse effects on rice development and productivity (Abd EL-Aty et al 2023). As a result, developing effective and long-term solutions to attenuate the harmful impacts of water deficit has become more important, especially considering present climatic variability (Mansour et al, 2023). This work explored the effectiveness of applied Si-NPs and Ksulphate in alleviating the negative effects of water shortage in rice.…”

Biochemical, physiological, and molecular responses of diverse olive cultivars to different irrigation regimes

“…The adverse impacts of drought stress on physiological processes inactivate damage to membrane lipids and impair nucleic acids as well as metabolic enzymes, which ultimately leads to a considerable reduction in plant development (Farooq et al, 2009;Mansoor et al 2023). Hence, water scarcity limits plant growth and productivity at varying levels, depending on the severity of stress (Mansour et al, 2023). Under drought stress, olives absorb water from the soil to maintain protoplasm hydration through osmoregulation.…”

Exogenous Salicylic Acid Alleviates Water Deficit Stress by Protecting Photosynthetic System in Maize Seedlings

“…However, it is still a major challenge to effectively apply these results to field production. Among them, exogenous plant growth regulators (PGRs) have been considered an effective means to improve drought tolerance in plants [3,13,14]. Therefore, an in-depth analysis of the role of PGRs on environmental stress response and its mechanism is urgently needed.…”