Mitigating Drought Stress in Sunflower (Helianthus annuus L.) Through Exogenous Application of β-Aminobutyric Acid

Abstract

Drought stress is a serious threat for sustainable crop production throughout the world especially in arid and semi-arid regions and one of the main constraints to sunflower (Helianthus annuus L.) production. Different mitigation strategies, including foliar spray of osmolytes such as β-aminobutyric acid (BABA), help the crop to combat drought conditions. A 2-year field study was conducted to evaluate the effect of exogenous application of BABA on the growth, productivity, and net return of sunflower under drought conditions. The experimental treatments comprised drought levels, viz., control (well watered (WW)); drought stress at vegetative stage (DVS); and drought stress at reproductive stage (DRS). Drought-mitigating treatments comprised foliar application of BABA, viz., 0 mM (control), 25 mM, 50 mM, and 75 mM with three replications. Foliar application of BABA under drought condition had significant effect on physiological traits, yield, and yield-related traits. Foliar application of 75-mM BABA solution improved SPADchlorophyll value and membrane stability index and maintained higher relative water contents. It also improved 1000-achene weight and achene yield, and produced about 41% and 44% more achene yield during 2018 and 2019 respectively compared with other treatments. Significant and positive correlations were also observed between yield and yield-contributing traits of sunflower under different water stress conditions. This finding suggests that foliar application of 75-mM BABA may be used as a viable option for sunflower growers to enhance achene yield and net benefit under drought conditions in arid and semi-arid regions.

Foliar Potassium Sulfate Application Improved Photosynthetic Characteristics, Water Relations and Seedling Growth of Drought-Stressed Maize

“…In addition, adverse effects imparted by DS depend on the intensity and duration of stress [15,16]. DS at critical growth stages, such as the seedling, vegetative or reproductive stages [17,18], leads to a severe reduction in relative water content and crop yield. Moreover, water deficit conditions at earlier growth stages when roots have not been fully developed results in stunted plant growth and a reduction in the binding of CO 2 [17,19,20].…”

Comparative Effect of Inoculation of Phosphorus-Solubilizing Bacteria and Phosphorus as Sustainable Fertilizer on Yield and Quality of Mung Bean (Vigna radiata L.)

“…After that, readings were recorded from a UV-vis spectrophotometer (V-73, Japan) at the wavelength of 410 nm. Further calculations were processed by the following Equation (2) [ 43 , 44 ]. where V is the final volume of plant/soil digested material after dilution (mL), V 1 is the volume of plant/soil digest used for P assessment purposes (mL), V 2 is the volume of flask used for assessment (mL), and Wt is the dry weight of plant/soil (g) [ 43 ].…”

“…Data of each parameter were taken in three replicates and shown as means ± standard error of the means (mean ± SEM). The significance of variables was assessed by analysis of variance (ANOVA) and means were ranked on Tukey’s HSD (honestly significant difference) test ( p ≤ 0.05) using Minitab ® Statistical Software (version: 20.3, USA) [ 44 ].…”

Photosynthetic activity and water use efficiency of Salvia verbenaca L. under elevated CO2 and water‐deficit conditions

“…Studies have also shown that elevated CO 2 causes a 20–30% increase in net assimilation rate, together with an increase in dry matter and yield of crops (Cruz et al, 2018; Pan et al, 2018; Xie et al, 2018). Rising levels of CO 2 , temperature and water‐deficit cause promising effects on plant growth and production, as the potential beneficial effects of elevated CO 2 include optimal growth yield in areas where drought currently causes crop failure (Shahzad et al, 2018; Wasaya et al, 2021). According to AbdElgawad et al (2015), elevated CO 2 has been shown to mitigate the stress impact of drought, and they quote examples of how the reduction in drought stress affects barley and alfalfa crops (Robredo et al, 2007; Zeid and Shedeed, 2006).…”