Abstract
The effects of climate temperature and water stress on growth and several stress markers were investigated in sweet basil plants. Some growth parameters (shoot length and number of leaves) and photosynthetic chlorophyll contents were determined every two days during plant growth, and foliage leaf material was collected after 15 and 21 days of treatment. Both climate temperature and water stress inhibited sweet basil plant growth; especially, total chlorophyll levels were decreased significantly in response to high-temperature treatments. Under strong stresses, basil plants induced the synthesis and accumulation of glycine betaine (GB) as a secondary osmolyte, although at less content when compared with the proline content under the same stress conditions. Proline concentrations particularly increased in leaves of both basil stressed plants, accomplishing levels high enough to play a crucial role in cellular osmoregulation adjustment. Stress-induced accumulation of these antioxidant compounds was detected in sweet basil. Therefore, it appears that sweet basil-treated plants are able to synthesize antioxidant compounds under strong stress conditions. On the other hand, total sugar concentrations decreased in stress-treated basil plants. Both temperature and water stress treatments caused oxidative stress in the treated plants, as indicated by a significant increment in malondialdehyde (MDA) concentrations. An increase in total phenolic and flavonoid concentrations in response to water stress and a highly significant decrease in carotenoid concentrations in basil leaves were observed; flavonoids also increased under high climate temperature conditions.
Highlights
Plants are challenged by hostile environments of temperature, drought, salinity, and heavy metals which disrupt cellular and developmental processes
Plant metabolism is altered in many different ways, including redox metabolism to remove excess levels of active oxygen species (AOS) and re-establish the cellular redox balance, and compatible solute production to stabilize proteins and cellular structures and/or to maintain cell turgor by osmotic adjustment [5,6,7]. e synthesis and accumulation of osmoprotectants (“osmolytes”) in the cytoplasm, a conserved phenomenon observed in all plants, including those tolerant and sensitive to stress, is considered as one of the most general responses to all abiotic stress conditions [8, 9]
Osmotic adjustment has been shown to be an effective component of stress tolerance, and accumulation of osmoprotectants such as proline, glycine betaine, gamma amino butyric acid (GABA), and sugars is a common molecular response observed in different plant compartments [3, 10]
Summary
Plants are challenged by hostile environments of temperature, drought, salinity, and heavy metals which disrupt cellular and developmental processes. Plants have developed complex and well-organized mechanisms to adopt and tolerate biotic and abiotic stress conditions [1]. Abiotic stresses such as water stress, salinity, cold temperature, anoxia, high light intensity, and nutrient imbalances usually and highly significantly affect plant growth, development, and their productivity. It has been demonstrated that some stress conditions such as temperature, water stress, salinity, and flooding, in general, resulted in increased soluble sugar levels, whereas low sugar levels are knowingly and perceptively seen under other abiotic stress conditions such as high light intensity irradiance, excess heavy metals, and nutrient deficiency [11]. Persistence of the turgidity is very essential for cell expansion in addition to various biochemical pathways and processes such as photosynthesis and maintaining enzymatic activities [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
