Effect of exogenous alpha-tocopherol on physio-biochemical attributes and agronomic performance of lentil (Lens culinaris Medik.) under drought stress

Abstract

Water being a vital part of cell protoplasm plays a significant role in sustaining life on earth; however, drastic changes in climatic conditions lead to limiting the availability of water and causing other environmental adversities. α-tocopherol being a powerful antioxidant, protects lipid membranes from the drastic effects of oxidative stress by deactivating singlet oxygen, reducing superoxide radicals, and terminating lipid peroxidation by reducing fatty acyl peroxy radicals under drought stress conditions. A pot experiment was conducted and two groups of lentil cultivar (Punjab-2009) were exposed to 20 and 25 days of drought induced stress by restricting the availability of water after 60th day of germination. Both of the groups were sprinkled with α-tocopherol 100, 200 and 300 mg/L. Induced water deficit stress conditions caused a pronounced decline in growth parameters including absolute growth rate (AGR), leaf area index (LAI), leaf area ratio (LAR), root shoot ratio (RSR), relative growth rate (RGR), chlorophyll a, b, total chlorophyll content, carotenoids, and soluble protein content (SPC) which were significantly enhanced by exogenously applied α-tocopherol. Moreover, a significant increase was reported in total proline content (TPC), soluble sugar content (SSC), glycine betaine (GB) content, endogenous tocopherol levels, ascorbate peroxidase (APX), catalase (CAT) peroxidase (POD) and superoxide dismutase (SOD) activities. On the contrary, exogenously applied α-tocopherol significantly reduced the concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2). In conclusion, it was confirmed that exogenous application of α-tocopherol under drought induced stress regimes resulted in membrane protection by inhibiting lipid peroxidation, enhancing the activities of antioxidative enzymes (APX, CAT, POD, and SOD) and accumulation of osmolytes such as glycine betaine, proline and sugar. Consequently, modulating different growth, physiological and biochemical attributes.

Quantifying Temperature and Osmotic Stress Impact on Seed Germination Rate and Seedling Growth of Eruca sativa Mill. via Hydrothermal Time Model

“…The maximum growth rate was found at 30 °C, and the minimum was found at 5 °C. These findings are consistent with several previous studies [ 23 , 26 , 34 , 48 , 53 , 54 ]. According to them, agronomic parameters are affected significantly by T and Ψ , and when the Ψ becomes more negative, both the rate and percentage of germination decrease (if they do not become completely inhibited) due to the water deficit [ 55 , 56 ].…”

“…The results of our study showed that increasing temperatures within the range of 20-30 • C resulted in an increase of 95% in germination, and the lowest value displayed a 25% decrease at 5 and 20 • C (~10 • C). The maximum growth rate was found at 30 • C, and the minimum was found at 5 • C. These findings are consistent with several previous studies [23,26,34,48,53,54]. According to them, agronomic parameters are affected significantly by T and Ψ, and when the Ψ becomes more negative, both the rate and percentage of germination decrease (if they do not become completely inhibited) due to the water deficit [55,56].…”

Enzymatic and biochemical responses to high temperatures and drought stress during the reproductive stage in lentil (Lens Culinaris Medik.)

“…In response to high temperature and drought stress, the concentrations of soluble sugars increased in almost all of the genotypes examined in our study. Our results are consistent with the ndings of Shah et al 41 who discovered a signi cant increase in soluble sugar content and proline content in lentil cultivars exposed to water de cit stress conditions. In lentil, Sehgal et al 26 reported similar results, showing a signi cant increase in soluble sugars in response to heat and drought stresses.…”

Using mathematical models to evaluate germination rate and seedlings length of chickpea seed (Cicer arietinum L.) to osmotic stress at cardinal temperatures

“…The highest theoretical CVG value will be obtained when all sown seeds germinated on the first day. This was calculated from the formula suggested by Shah et al [ 12 ].…”

“…The earth’s climate is changing drastically in recent decades and these climate changes affect all the physiological phases of plant growth and development [ 12 ]. This changing climate increases the intensity and frequency of the abiotic factors that contrarily reduced agricultural production [ 13 ].…”