Evaluation of Plant Bio-Regulators and Antioxidants on Fruit Quality and Physiological Attributes of Pomegranate (Punica Granatum L.) cv. Bhagwa

Effect of Plant Growth Regulators on Yield, Fruit Quality, and Physiological Traits of Mango (Mangifera indica L.) cv. ‘Dasheri’

Effect of Exogenous Application of Gibberellic Acid and 1-Naphthaleneacetic Acid on the Growth, Yield, Quality, and Storage Behavior of Strawberry cv. ‘Chandler’ in the Northeast Region of India

Foliar Application of a Sargassum spp.-Based Biostimulant Improves Fruit Quality and Antioxidant Enzyme Activity in Melon

Seaweed-derived biostimulants are promising tools for improving crop performance and fruit quality in sustainable horticulture. This study evaluated the effects of foliar application of a liquid Sargassum spp. extract on the commercial quality, nutraceutical attributes, and antioxidant response of melon fruit (Cucumis melo L. cv. ‘Cruiser’). Four extract concentrations (0, 1.5, 3.0, and 4.5%, v/v) were applied in a randomized complete block design with six replications. Compared with the control, the 1.5% treatment increased (p ≤ 0.05) fruit firmness (33.5%), total soluble solids (25.4%), flesh thickness (16.5%), and ascorbic acid content (51.2%). Total phenolic and flavonoid contents also increased by 22.9% and 22.4%, respectively (p ≤ 0.05). Antioxidant enzyme activities increased in a concentration-dependent manner (p ≤ 0.05), highlighted by a 207.1% increase in catalase activity at 4.5% with catalase. In contrast, the highest concentration reduced carbohydrate content by 49.3% (p ≤ 0.05), while fruit yield remained unaffected (p > 0.05). Overall, 1.5% provided the best balance between commercial and nutraceutical quality while avoiding the adverse biochemical responses observed at 4.5%. These findings suggest the potential use of Sargassum spp. extract as a biostimulant for sustainable melon production under the conditions of this study.

Preharvest Foliar Application of Ascorbic Acid Improves Growth, Yield, and Postharvest Quality of Broccoli ( Brassica oleracea var. italica)

Broccoli is a rich source of nutrients and bioactive compounds. Unfortunately, its shelf life is limited due to physicochemical losses and microbiological degradation. Therefore, the present research aimed to determine the efficacy of ascorbic acid (0, 100, 200, and 300 mg L −1 ) as a preharvest foliar spray for improving broccoli growth and morphological characteristics, yield, and postharvest storage quality. Among the used ascorbic acid concentrations, the 300 mg L −1 treatment was the most effective. Preharvest foliar application of ascorbic acid significantly increased the number of leaves (50%), head diameter (70%–80%), head fresh weight (27%), root length (28.6%), and root fresh and dry weights by 29% and 39%, respectively, compared with the control. The ascorbic acid application significantly improved the postharvest quality characteristics such as total soluble solids (TSS), ascorbic acid (60%), total phenolics (40%), and maintained the chlorophyll concentration (50% higher). Additionally, antioxidant enzymes, including superoxide dismutase (SOD; 120%), peroxidase (POD; 80%), and catalase (CAT; 150%), was markedly enhanced. Total flavonoids increased by 30%, while antioxidant activity improved by 60% compared with untreated plants. Moreover, ascorbic acid significantly reduced weight loss (50%), chlorophyll degradation, ion leakage (40%), and accumulation of hydrogen peroxide (35%) and malondialdehyde content (40%) in broccoli heads as compared to the control during storage. In conclusion, ascorbic acid preharvest treatment could be considered an effective approach to enhance the shelf life (6–8 days) and yield of broccoli than the control.

Influence of Winter Pruning Intensity on Growth, Yield and Fruit Quality in Pomegranate (Punica granatum L.) cv. Bhagwa

Pomegranate (Punica granatum L.) is a commercially important fruit crop valued for its nutritional, medicinal and export potential. However, its natural tendency to produce numerous suckers results in excessive canopy density, which limits light penetration and air circulation and adversely affects photosynthesis, fruit yield and quality. Information on the optimum winter pruning intensity for pomegranate under the subtropical sub-montane and low-hill conditions of Himachal Pradesh remains limited. The present study was therefore conducted during 2022 and 2023 to evaluate the effects of pruning at 10 cm (T₁), 15 cm (T₂), 20 cm (T₃) and 25 cm (T₄), compared with an unpruned control (T₅), on the growth, fruit yield and fruit-quality characteristics of five-year-old ‘Bhagwa’ pomegranate trees. The experiment was laid out in a randomised block design, and pruning was conducted during the second fortnight of January in both years. Moderate pruning at 20 cm produced the highest fruit set (78.87%) and fruit yield (9.93 kg tree⁻¹). Severe pruning at 25 cm produced the highest leaf area (12.54 cm²), total chlorophyll content (4.17 mg g⁻¹), fruit weight (217.85 g), fruit length (84.81 mm), fruit breadth (76.90 mm), TSS (13.07 °Brix), TSS/acid ratio (42.82), ascorbic acid content (20.08 mg 100 mL⁻¹), total sugars (12.40%), anthocyanin content (43.75 mg 100 mL⁻¹), total phenolic content (124.12 mg GAE 100 mL⁻¹), juice content (35.12%) and aril content (55.97%). These findings indicate that moderate winter pruning at 20 cm is suitable for maximising fruit yield, whereas severe pruning at 25 cm is more effective for improving fruit quality.

Foliar Application of Hempseed Press Cake-Derived Protein Hydrolysate Enhances Yield, Fruit Quality, and Antioxidant Properties of Strawberry (Fragaria × ananassa Duch.) Grown Under Smart Greenhouse Conditions

Hempseed press cake-derived protein hydrolysate (HPH) is a promising plant biostimulant, but its effects on strawberry fruit production under smart greenhouse conditions remain unclear. The objective of this study was to evaluate the effects of foliar HPH application on growth, mineral accumulation, reproductive traits, yield, fruit quality, and antioxidant properties of strawberry cv. ‘Pharachatan 80’. Plants were grown in a smart greenhouse and treated with water (control), a commercial biostimulant, and HPH at 7.5 and 10.0% (w/v) (HPH7.5 and HPH10.0, respectively). Foliar application was initiated 25 days after transplanting and repeated weekly for five applications. HPH applications showed clear concentration-specific improvements in vegetative growth, mineral accumulation, reproductive performance, fruit yield, and antioxidant quality. As the most effective treatment for overall crop performance, HPH7.5 enhanced plant growth and mineral accumulation, particularly K and Mg. Consequently, it improved both yield components (fruit set, number, weight, size, and total yield) and fruit quality attributes, such as total soluble solids, total phenolics, flavonoids, ascorbic acid, and ABTS radical-scavenging activity. Conversely, HPH10.0 was more closely associated with N, P, Ca, Fe, Zn, and Mn accumulation, as well as fruit firmness and total anthocyanin content, and DPPH radical-scavenging activity. Principal component analysis confirmed distinct response patterns between HPH concentrations. Thus, HPH7.5 serves as an effective foliar biostimulant to improve strawberry productivity and quality in smart greenhouses.