Effect of Drought Stress on Certain Morphological and Physiological Characteristics of a Resistant and a Sensitive Canola Cultivar

Abstract

Water stress is one of the main abiotic factors that reduces plant growth, mainly due to high evaporative demand and low water availability. In order to evaluate the effects of drought stress on certain morphological and physiological characteristics of two canola cultivars, we conducted a factorial experiment based on a completely randomized design. The findings show that drought stress exacerbations result in the plant's response to stress due to increased canola resistance caused by changes in plant pigments, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase and malondialdehyde, glucose, galactose, rhamnose and xylose. These in turn ultimately influence the morphological characteristics of canola. Drought stress reduces the concentration of carotenoids, chlorophyll a, chlorophyll b, total chlorophylls; however, glucose, galactose, rhamnose, xylose, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase, malondialdehyde (in leaves and roots) and the chlorophyll a and b ratios were increased. Reduction of plant height, stem height, root length, fresh and dry weight of canola treated with 300 g/l PEG compared to non‐treatment were 0.264, 0.236, 0.394, 0.183 and 0.395, respectively. From the two canola cultivars, the morphological characteristics of the NIMA increased compared to the Ks7 cultivar. Interaction effects of cultivar and drought stress showed that NIMA cultivar without treatment had the highest number of morphological characteristics such as carotenoid concentration, chlorophyll a, chlorophyll b, total chlorophylls a and b, whereas the cultivar with 300 g/l PEG (drought stress) had the highest amount of proline, malondialdehyde, soluble sugars and enzymes in leaves and roots. Increasing activity of oxidative enzymes and soluble sugars in canola under drought stress could be a sign of their relative tolerance to drought stress.

Physio‐morphological, biochemical, and anatomical traits of drought‐tolerant and susceptible sorghum cultivars under pre‐ and post‐anthesis drought

“…Passioura (1983) suggested that a smaller root system may be beneficial under drought, while Khodabin et al . (2020) revealed that drought stress in the early growth stages reduced the root biomass in canola. However, drought tolerance can also be improved by enhanced assimilate allocation to the roots and increased moisture uptake capability (Mathew et al ., 2019).…”

“…Root biomass has been shown to be associated with drought stress tolerance (Ekanayake et al, 1985), while Nour and Weibel (1978) reported that root weight could be used as an indicator of drought tolerance in grain sorghum. Passioura (1983) suggested that a smaller root system may be beneficial under drought, while Khodabin et al (2020) revealed that drought stress in the early growth stages reduced the root biomass in canola.…”

Alleviating of Water Deficit in Eggplant by Two Different Mulches

“…Drought stress significantly reduced the plant height of eggplant (Kirnak et al, 2001). The decrease in plant height in response to drought stress was observed in other plants such as canola (Khodabin et al, 2020), wheat (Kamal et al, 2019), and tomato (C. . The results showed that the application of both mulches reduced the adverse effects of water shortage on plant height and this reduction has been more with increasing depth of the PM.…”

Systematic analysis and expression of Gossypium 2ODD superfamily highlight the roles of GhLDOXs responding to alkali and other abiotic stress in cotton

“…Chlorophyll is a typical representative indicator of photosynthesis. As the important photosynthetic pigment, it can reflect the photosynthetic energy efficiency [ 69 ]. After Na 2 CO 3 stress, the Pro and chlorophyll contents of pYL156: GhLDOX3 were evidently more than pYL156 (Fig.…”