The effect of supplementary light on the photosynthetic apparatus of strawberry plants under salinity and alkalinity stress

Abstract

Considering the destructive effect of stresses on the photosynthetic apparatus of plants and the important role of light in photosynthesis, we investigated the effect of complementary light on the photosynthetic apparatus under salinity and alkalinity stress conditions. Light-emitting diodes (LEDs) in monochromatic blue (460 nm), monochromatic red (660 nm), dichromatic blue/red (1:3), white/yellow (400–700 nm) at 200 μmol m−2 S−1, and without LED treatment were used. The stress treatments were in three stages: Control (no stress), Alkalinity (40 mM NaHCO3), and Salinity (80 mM NaCl). Our results showed that salinity and alkaline stress reduced CO2 assimilation by 62.64% and 40.81%, respectively, compared to the control treatment. The blue light spectrum had the highest increase in water use efficiency (54%) compared to the treatment without supplementary light. Under salinity and alkalinity stress, L, K, and H bands increased and G bands decreased compared to the control treatment, with blue/red light causing the highest increase in L and K bands under both stress conditions. In salinity and alkalinity stress, white/yellow and blue/red spectra caused the highest increase in H bands. Complementary light spectra increased the G band compared to the treatment without complementary light. There was a significant decrease in power indices and quantum power parameters due to salt and alkalinity stress. The use of light spectra, especially blue, red, and blue/red light, increased these parameters compared with treatment without complementary light. Different light spectra have different effects on the photosynthetic apparatus of plants. It can be concluded that using red, blue spectra and their combination can increase the resistance of plants to stress conditions and be adopted as a strategy in planting plants under stress conditions.

Chlorophyll a fluorescence as a tool to monitor physiological status in the leaves of Artemisia ordosica under root cutting conditions

“…The rapid ChlF test was developed specifically as a biophysical tool for evaluating the cascade of chloroplast redox reactions at microsecond or millisecond scales ( Kalaji et al., 2016 ; Esmaeilizadeh et al., 2021 ; Sharma et al., 2021 ; Shamsabad et al., 2022a ; Sieczko et al., 2022 ; Dąbrowski et al., 2023 ). The link between the physiological condition of samples and the fluorescence transient has also been the subject of important empirical research in the past, including demonstrating the direct or indirect association between the physiological state of leaves and ChlF transients.…”

Underlying Mechanisms of Action to Improve Plant Growth and Fruit Quality in Crops under Alkaline Stress

“…The use of rootstocks can increase the total soluble solids and nutritional status of grapevine fruits grown in alkaline environments [51]. In contrast, the use of light-emitting diodes in monochromatic blue (460 nm), monochromatic red (660 nm), and dichromatic blue/red (1:3) light at 200 μmol m À2 s À1 enhances electron transport per reaction center and the probability of transferring electrons from the exciton into the electron transport system, promoting gas exchange in alkalinity-stressed strawberry plants [47,99].…”

Gamma-Aminobutyric Acid-Mediated Alkalinity Stress Alleviation in Lollo Rosso Lettuce under Diverse Light Spectra

“…It was suggested that B light significantly increases plant tolerance to alkaline stress through various physiological and biochemical mechanisms [2,44]. When exposed to B light, plant photoreceptors, such as cryptochromes and phototropins, are activated, initiating a signaling cascade that triggers responses to combat alkaline stress [44].…”

“…In this pursuit of resilient agriculture, a particular stressor that warrants attention is alkalinity stress [1]. Alkaline soil and irrigation water conditions can severely hamper plant growth and productivity [1,2]. Excessive alkalinity in water can disrupt the delicate pH balance essential for proper nutrient uptake in plants, leading to nutrient deficiencies and reduced growth.…”

“…Plant growth and productivity is an intricate interplay between external and internal factors. Environmental factors like light, temperature, nutrients, and water profoundly influence crop growth [2]. Controlled environment agriculture (CEA) has been introduced to produce crops safely [5].…”