Water scarcity and increasing salinity stress are significant challenges in the farming sector as they often exacerbate each other, as limited water availability can concentrate salts in the soil, further hindering plant growth. Lettuce, a crucial leafy vegetable with high nutritional value, is susceptible to water availability and quality. This study investigates the growth and development of lettuce plants under water scarcity and varying levels of salinity stress to identify effective strategies for reducing water consumption while maintaining or improving plant productivity. Field experiments were designed to simulate three drought levels (50, 75, and 100% of class A pan evaporation) and three salinity stress levels (control, 1500, and 3000 ppm NaCl), assessing their impact on lettuce’s morphological and biochemical parameters. The combination of reduced water supply and high salinity significantly hindered growth, underscoring the detrimental effects of simultaneous water deficit and salinity stress on plant development. Non-stressed treatment enhanced nitrogen, phosphorus, and potassium contents and progressively decreased with the reduction in water supply from 100% to 50%. Interestingly, higher salinity levels increased total phenolic, flavonoid, and antioxidant activity, suggesting an adaptive stress response. Moreover, antioxidant activity, evaluated through DPPH and ABTS assays, peaked in plants irrigated with 75% ETo, whether under control or 1500 ppm salinity conditions. The Yield Stability Index was highest at 75% ETo (0.95), indicating robust stability under stress. The results indicated that lettuce could be cultivated with up to 75% of the water requirement without significantly impacting plant development or quality. Furthermore, the investigation demonstrated that lettuce could thrive when irrigated with water of moderate salinity (1500 ppm). These findings highlight the potential for reducing water quantities and saline water in lettuce production, offering practical solutions for sustainable farming in water-scarce regions.

Heat stress is one of the most critical environmental abiotic stresses that can negatively affect plant growth. This article investigates the role of a plant growth promoter (Benzylaminopurine) in tomato fields in regard to its ability to withstand high-temperature conditions resulting from greenhouse gas emissions and climate changes. Three genetically different tomato cultivars (Castlerock, GS 12-F1, and Fayrouz F1) were sprayed with 2% 6-Benzylaminopurine (BAP) at 300 and 600 ppm; then, growth and yield components, physio-biochemical characteristics, and antioxidant enzyme activities were determined. The results showed that the highest BAP concentration (600 ppm) enhanced the ability of tomato plants to withstand high temperatures and the maximum dose of BAP improved chlorophyll (71.7 spad units) in GS 12 leaves, while the same dose enhanced proline contents (24.91 mg/100g FW), total antioxidants (83.35 µmol Trolox/g dw), total phenolics (20.99 mg/g dw), Superoxide dismutase (33.74 U/g), peroxidase (46.30 U/g), and polyphenol oxidase (64.10 U/g) in Fayrouz F1 leaves. Application BAP on tomatoes moderately improved fruit quality, such as ascorbic acid and maturity degree, while BAP applications reduced TSS and acidity. In this investigation, taste index was not affected by Benzylaminopurine application but by tomato genotype. The highest number of fruits/plant (45.7), fruit yield/plant (3.98 kg), and total yield (103 tons/ha) were obtained from the GS 12 genotype.

Vegetables accumulate considerable amounts of nitrates that enter the human body through nutrition, causing severe problems. This study aims to determine celery plants’ response to replacing mineral nitrogen fertilizers with bio-nanoparticles. Three different treatments of nano bio-nitrogen fertilizer (20, 30, and 40 ppm) in addition to traditional nitrogen (NH₄NO₃) treatment (100 kg N/acre) were applied on two celery cultivars (Balady and Utah Tall 52–75). Plant growth parameters, vitamin C, carotenoids, nitrate accumulation, macro-nutrient uptakes, and antioxidant activities were determined at the vegetative marketing stage. Our findings reveal a significant positive impact of replacing conventional nitrogen fertilizers with bio-nano-synthesized forms. Notably, applying bio-nanoparticles improved celery yield efficiency, ranging from 5.1 to 5.8 tons per acre, suggesting a viable alternative to traditional fertilization methods. Furthermore, transitioning from mineral to organic fertilizers in nanoparticle form reduced nitrate accumulation in fresh celery crops, decreasing nitrate levels from 342.5 ppm to as low as 100 ppm. This environmentally conscious approach offers a sustainable solution to mitigate chemical residues and enhance celery’s flavor, nutritional value, and health benefits. Specifically, our results demonstrate alleviated nitrate contents in fresh celery leaves after applying bio-nano-fertilizer. Nitrate levels in treated plants decreased by up to 70.0% compared to traditional fertilization methods. This highlights the potential of organic nano-fertilizers to address concerns related to nitrate accumulation, thereby promoting safer and healthier vegetable consumption. By advocating for organic nano-fertilizers, we propose a promising strategy to optimize celery fertilizing management, ensuring sustainable farming and consumer well-being.

Blossom-end rot (BER) is a physiological disorder caused by calcium deficiency, often paired with moisture stress and irregular traditional watering practices. To understand the biological mechanism affecting the incidence of BER, different tomato genotypes were cultivated in sandy soil and were traditionally irrigated. Nine tomato genotypes were investigated to assess their susceptibility to BER, and the incidence rate varied from 7.1% in “Voskhod” to 57.6% in “Majnat” genotypes. This study also comprehensively analyzed various physiological and biochemical parameters to elucidate their correlation with BER incidence in tomato plants. Our findings revealed a range of parameters positively correlated with BER incidence, including the relative water content of roots, the number of fruits per plant, vitamin C content, and potassium content. Parameters related to fruit quality, such as titratable acidity, peroxidase content, and firmness degree, also showed positive correlations with BER incidence. Conversely, parameters such as total yield per hectare, chlorophyll content, average plant height, and calcium content demonstrated strong negative correlations with BER incidence, suggesting potential protective effects against this disorder. This study highlights that genotypes with higher marketable yields, such as ‘Voskhod’ (65 tons/ha), showed lower BER incidence, underscoring the importance of selecting the appropriate genotype in improving yield and reducing blossom-end rot in tomato fields. Conversely, cultivars with high BER sensitivity, such as ‘Chelnok’ (26.3 tons/ha), require specially designed cultivation management to avoid production declines.

Fennel fruits (Foeniculum vulgare Mill.) represent one of the plant-based natural spices. This study aims to improve the fruit yield and essential oil (EO) quality by reducing the undesirable component, estragole, under different fertilizer treatments. The fertilizers included chemical nitrogen, phosphorus, and potassium (NPK), and also the organic additive, rabbit manure (RM). For bio-fertilization, plants were inoculated with a mixture of N-fixing bacteria, and P- and K-solubilizing bacteria with/without vesicular-arbuscular mycorrhizal fungi. The results showed that fruit and EO yield parameters, total phenolic content (TPC), total flavonoid content (TFC), and DPPH scavenging activity of fruit extracts were enhanced by fertilizer treatments in both growing seasons. NPK at 150% of the recommended dose (NPK150) and RM at 60 m³/fed (RM60) recorded the highest values of plant height, umbel number/plant, 100-fruit weight, fruit yield, chlorophyll, carbohydrates, N and P content, EO content, and yield. TPC and TFC were enhanced by using biological fertilizers. DPPH scavenging activity was higher in organically and biologically fertilized fennel. The GC-MS analyses of EO revealed higher contents of the desirable trans-anethole in the organically and chemically fertilized fennel. However, the highest proportion of estragole, the undesirable compound, was recorded for NPK150 and unfertilized plants. On the contrary, increases in the EO content and yield of fennel fruits were achieved by RM along with a reduction in estragole, enhancement in trans-anethole, and increments in other favorable compounds such as fenchone and limonene. In addition, the inhibition of estragole formation was recorded with bio-fertilizers, which also increased the trans-anethole content. Furthermore, the trans-anethole/estragole ratio was significantly higher with the application of organic and bio-fertilization. Hence, organic and bio-fertilizer resources can produce high-quality fennel fruit and EO. The reduction in the use of chemical fertilizers can help to reduce environmental pollution.