Sami Asir Al-Robai

Increasing water demand and the use of treated gray water as an alternate source for irrigation are gaining global importance. This study evaluated the treatment of gray water using a natural adsorbent corn cob filter and investigated the effects of treated gray water on the growth of two spinach varieties (Sindhi and Prikli). The current study showed a significant reduction in morpho-physiological and antioxidant attributes in both spinach varieties when subjected to untreated gray water. However, treated gray water significantly improved the plant root/shoot ratio, water and chlorophyll contents, activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), plant soluble sugar contents, and reduced concentration of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents. Moreover, both spinach varieties significantly varied in response to gray water treatment. The Sindhi variety showed comparatively better growth and physio-biochemical attributes than the spinach variety Prikli. It can be concluded that treated gray water may be considered as an alternative for irrigation of horticultural crops.

Climate change is affecting the planet, compromising survival and altering forest ecosystems. Investigating climatic variations in all regions is important. The aim of this research was to assess such variations in the W and Pendjari Biosphere Reserves in Benin from 1985 to 2015 and predict climate up to 2045. Drought frequency was assessed by using the Standardized Precipitation and Evapotranspiration Index (SPEI) and correlation was performed between climatic variables. Then a predictive analysis was computed. From 1985 to 2015, there was change in the climate with few severe dry and wet years while no extreme climatic condition was noticed. Most of the years showed nearly normal climatic conditions. The predicted climate indicates an absence of extreme conditions up to 2045 but an increase in the annual humidity is expected. A low decrease in annual mean temperature with high confidence is expected. Decision-makers can better organize adaptation programs and sensitize people in the reserves on their role in environmental conservation and mitigation of climate change using these outputs.

Cissus rotundifolia, Cyphostemma digitatum, and Cissus quadrangularis which belong to Vitaceae family are used as local traditional vegetables by local communities in Saudi Arabia and different regions in Asia for nutritional and therapeutic purposes. They were analyzed in this study in order to provide scientific evidence for their usage as nutritional and medicinal herbs. The protein, fat, fibre, cyanogenic glycoside, phytic acid, flavonoid, and tannin contents of the three species differed significantly (P < 0.05). Results from the nutritional analysis revealed the richness of C. rotundifolia leaves in crude protein (14.54%), carbohydrates (52.32%), fats (6.99%), and energy value (330.35 Kcal/100 g). C. rotundifolia and C. digitatum leaves showed comparable amounts of both vitamins C and A. The highest crude fiber was found in C. quadrangularis (23.82%), which also exhibited a good carbohydrate content (57.20%). Calcium was the most abundant mineral in the studied whole leaf extracts, followed by potassium. C. quadrangularis contained the highest concentrations of sodium (236 mg/100 g), iron (29 mg/100 g) and the lowest level of magnesium (96 mg/100 g). The concentrations of heavy metals in all samples were below the permissible level in food. In terms of anti-nutritional factors, all extracts had comparatively low levels of cyanogenic glycoside, phytate, alkaloid, and saponin contents. The leaves of C. quadrangularis contained significantly high levels of phenol, flavonoid, tannin, and proanthocyanidin content. C. rotundifolia leaves had a high level of DPPH radical quenching power (IC50 = 52.27 µg/mL) that was comparable to that of the standard (IC50 = 51.47 µg/mL). Inhibitory activities against alpha-amylase significantly varied among the extracts analyzed. The leaves of C. quadrangularis strongly inhibited alpha-amylase, and their impact was close to the effect of acarbose as a standard anti-diabetic agent. The findings revealed that the studied leafy wild plants can be used as a good source of various nutrients and beneficial biochemicals. Keywords: Cissus rotundifolia, Cyphostemma digitatum, Cissus quadrangularis, nutrients, anti-nutrients, bioactive compounds

Soil’s contamination with heavy metals is a serious issue, and assessing their levels, regulating their sources, and finding cost-effective technology to limit their toxic effect and soil cleanup are of high priority. The focus of this study was to find out the extent of priority hazard heavy metal contamination in soils close to the Al-Janabeen water reservoir dam in Baljurashi, KSA, and the extent of their accumulation in the Dodonaea viscosa Tacq plant. Soil and plant samples were analyzed for heavy metal concentration using inductively coupled plasma spectroscopy (ICPS). Quantitative single and integrated contamination indices were used to characterize and evaluate the degree of heavy metal contamination in soils. The biological concentration factor (BCF) and the translocation factor (TF) were utilized to determine the extent of transfer and accumulation of heavy metals in the D. viscosa plant. Soil analysis showed the presence of Mn, Cu, Zn, Co, Cr, and Pb among the prioritized heavy metals with Cu, Zn, and Pb values being higher than those in natural background levels. The mean concentration order was Fe > Mn > Zn > Cu > Pb > Cr > Ni > Cr > Co. The single contamination indices’ quantification indicated marked contamination due to Mn, Zn, Cu, Co, Cr, and Pb elements. While integrated contamination factors’ computation showed low ecological risk due to accumulative metals of concern, Nemerow’s index (NI) showed that Cu, Zn, and Pb were the three most abundant pollutants in the examined soils. Analysis of plant parts showed the presence of Mn, Cu, Ni, Zn, Co, Cr, Cd, and Pb at varying quantities in various plant sections. Both BCF and TF factors were less than one, indicating that the D. viscosa plant was limited in its ability to phytoextract and accumulate the metals from the soil. This study suggests more research to locate suitable native plants for phytoremediation and soil cleaning is required in addition to the appropriate planning and management of landfills in order to ensure agricultural sustainability.

Nitrogen (N) represents the most important nutrient for plant growth and productivity, but extreme and ineffective usage of N fertilizer results in boosted plant production expenditures and environmental contamination. For the world’s sustainable food production and environmental profits, there has been increased research interest in reducing the use of N fertilization along with improving plant N deficiency (ND) tolerance. Dopamine (DA), a potential antioxidant, mediates several physio-biochemical processes in plants under normal or stressful conditions. However, their roles in increasing ND tolerance in crisphead lettuce are not well-documented. We investigate the role of DA concentration (0.50 and 100 µM) on the growth and yield of crisphead lettuce plants under ND. Under normal conditions (100% recommended N fertilizer dose), DA (50 and 100 μM) application significantly enhanced growth, chlorophyll concentration, N%, antioxidant enzymes activity, as well as yield and its components, decreased nitrate accumulation and oxidative biomarkers compared to untreated plants (0 μM DA). ND significantly decreased plant growth and yield attributes as well as evoked oxidative impairment and nitrate accumulation as compared to 100% recommended N fertilizer dose in the absence of DA. However, within ND conditions, the application of DA concentrations significantly mitigated ND-induced oxidative burst and improved plant growth, chlorophyll concentration, N%, nitrate concentration, peroxidase, catalase, superoxide dismutase, total soluble solid, vitamin C, dry matter %, and total sugars, over 0 μM DA treated plants. Current findings highlighted that exogenous application of 100 μM DA could reinforce the crisphead lettuce plant’s resilience to ND by minimizing reactive oxygen species accumulation and promoting enzymatic antioxidants alongside growth, yield, and quality improvement. The beneficial effects of DA in lessening ND’s drastic impacts on crisphead lettuce resulted from upregulating antioxidant enzyme activity, impairment of oxidative biomarkers, and maintaining chlorophyll levels. The current findings open pioneering prospects to reduce nitrogen fertilization by DA application without any drastic effect on plant productivity. But further research is needed to fully understand DA effects and their mechanisms in inducing ND tolerance in different plant species, including crisphead lettuce.

Maize is one of the most economically important cereal crops worldwide. Salinity coupled with waterlogging is a major challenge for successful crop production. Understanding the underlying mechanisms and impacts of individual and combined salinity and waterlogging stress on the morpho-physio-biochemical and molecular responses and oxidative metabolism of maize during stress and recovery periods is essential. The present study was carried out to assess the response of four hybrid maize cultivars viz. DK-6142, FH-1231, FH-949, and MALKA-2016 under individual and combined salinity and waterlogging conditions. The treatments comprised the control (no stress), NaCl (salinity with 10 dSm⁻¹), WL (waterlogged conditions with 3 cm flooding), and NaCl + WL (combined salinity and waterlogging stress). The data regarding morpho-physiological attributes were collected at 22 days after sowing (DAS; stress phase) and 30 DAS (recovery phase). The results revealed that both stresses, either individually or in combination, substantially reduced the root-shoot length, root-shoot fresh and dry weights, leaf width, and the number of leaves per plant as well as the leaf chlorophyll (Chl) and carotenoids contents; however, the inhibitory effects were more severe in combined stresses than for individual stress factors in many cultivars. Both individual and combined stress conditions enhanced hydrogen peroxide (H₂O₂) accumulation, whereas the antioxidant enzyme activities, i.e., superoxide dismutase (SOD), peroxidase (POD) catalase (CAT), and ascorbate peroxidase (APX), remained higher under stress conditions compared to the control. The expression levels of antioxidant genes (CAT and POD) were also upregulated under stress conditions. All of the cultivars recovered better from individual stresses than combined stress conditions; however, the hybrid DK-6142 performed better than the other maize hybrids under stress conditions and showed faster recovery.