Abstract Low temperature, inadequate light intensity and short-day length are the main limiting factors for watermelon ( Citrullus lanatus ) production during winter. This study investigated the effects of environmental manipulation including temperature, supplementary light and photoperiod extension on the growth, physiology, yield and quality of winter grown watermelon. A completely randomized design was used for the evaluation of five environmental treatments: T0; control, T1; heating, T2; heating + red and blue light, T3; red and blue light and T4; high powerful LED. Supplementary red: blue light ratio was 70:30 from 16.00 to 22.00 and 6.00 to 10.00 with a light intensity of 600 μmol · m −2 · s −1 and for the high-powerful-LED intensity were 1500 μmol · m −2 · s −1 from 6.00 to 19.00. The results revealed that among the treatments, T4 showed the best physiological responses and led to early flowering, better anther dehiscence and pollen release and the highest fruit set rate (98%). Fruit yield and quality attributes were significantly improved in T2 and T4 which have the maximum yield per plant (1.59 kg · plant −1 ), flesh thickness, flesh color and the highest sugar content (12.8 °Brix). Control, on the other hand, yielded smaller, misshapen fruits that were less sweet and less marketable. Hence, it was concluded that regulating the temperature and lighting strategies is essential to optimize the environment which has potential for enhancing the yield and quality of winter watermelon production.
This study investigated the effects of five concentrations of magnesium sulphate on selected microgreen species. Six plant species – broccoli, mustard, cress, basil, sunflower and cucumber – were treated with MgSO4 solutions containing magnesium at concentrations of 0, 10, 20, 30, 40 and 50 mg · L−1. The content of water-soluble magnesium and calcium, fresh yield, dry matter content, vitamin C, total phenols, flavonoids and antioxidant activity were evaluated in all species. Biofortification significantly increased (p < 0.05) the Mg content in all tested species without negatively affecting yield. The highest water-soluble magnesium content (after the application of 50 mg · L−1) was observed in cucumber (1076 mg · kg−1 FW), while the lowest was found in sunflower (369 mg · kg−1 FW). Compared with the control, the application of 50 mg · L−1 increased the magnesium content in plants by 67% in mustard, 81% in sunflower, 137% in broccoli, 172% in cress, 186% in cucumber and 262% in basil. Furthermore, 50 mg Mg · L−1 significantly enhanced (p < 0.05) total phenol content, flavonoids, vitamin C and antioxidant activity in broccoli.
The effect of a high-voltage electrostatic field on postharvest preservation of carnation (Dianthus caryophyllus L.) was studied. The morphological indexes such as cut flower morphology, colour char-acteristics, flower weight, water content, stomatal traits (including stomatal closure ratio (SCR) and stomatal size), and physiological indexes such as chlorophyll, anthocyanin, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), malondialdehyde (MDA) were recorded in the whole process by setting field intensities of 10 kV & centerdot; m-1, 30 kV & centerdot; m-1 and the control group (CK) (0 kV & centerdot; m-1). The results showed that the vase period of 10 kV & centerdot; m-1 treatment was significantly increased, which was 1.52 days longer than that of CK, with consequent effects on flower colour brightness. Also, the effect on flower colour brightness was obvious. Compared with CK, at 10 kV & centerdot; m-1, anthocyanins increased by 8.1%, which improved flower colour brightness, and SOD activity increased by 11.2%, indicating reduced oxidative stress and better maintenance of flower weight and water content. Interestingly, the SCR of 10 kV & centerdot; m-1 was 4.85 times higher than that of CK, with a decrease of 9.4% in stomatal length and 10.68% in stomatal width. To sum up, 10 kV & centerdot; m-1 can prolong the vase life of carnation significantly and may delay the flower wilting time by adjusting the stomatal opening-closing ratio. The research provides a new idea for the fresh-keeping technology of cut flowers.
Indian-strawberry (Duchesnea indica) covering (IC) represents an environmentally friendly and cost-effective 'grass- to-grass' weed suppression strategy in orchard management, warranting further investigation into its impacts on soil microecology. Soil samples under IC were analysed for nutrient content, microbiome composition, and metabolome profiles to elucidate the effects of snakeberry coverage on soil microbial communities and metabolite dynamics. IC significantly improved soil physicochemical properties, with longer coverage duration yielding more pronounced enhancements. Soil organic matter and available phosphorus showed heightened environmental sensitivity and relatively rapid accumulation rates. IC exerted regulatory influence on soil microbial community structure without altering the dominant taxonomic composition, which remained primarily Proteobacteria and Ascomycota. Metabolites in covered soils were significantly enriched in pathways such as 'biosynthesis of plant secondary metabolites' with arachidonic acid identified as a potential key metabolite of interest. Overall, IC contributes positively to the regulation of soil microecology and enhancement of soil quality, providing theoretical support for the promotion and application of snakeberry coverage in orchard soil management.
Strawberries are very sensitive fruits prone to mechanical damage, water loss, and fungal attacks, especially grey mould (Botrytis cinerea), which is one of the main causes of postharvest diseases. Traditional methods of postharvest preservation, including applying preharvest fungicides and cold storage, have their own limitations, and therefore, effective alternative methods are needed. Prohexadione-Ca (Pro-Ca) and calcium chloride (CaCl2) are environmentally friendly postharvest treatments that increase the shelf life of strawberries. These compounds reduce excessive growth, strengthen the cell wall, and deter enzymatic breakdowns, thus slowing down the ripening process. The current study determined the effects of different levels of Pro-Ca (10, 15, and 20 ppm) and CaCl2 (1%, 2%, and 3%) on postharvest characteristics of strawberries kept at 4°C for 20 days. The retention of total soluble solids (TSS), titratable acidity(TA), vitamin C, phenolic compounds, and flavonoid contents showed significant improvements, accompanied by decreases in weight loss, severity of the disease, and microbial growth, with optimal doses depending on the specific parameter evaluated. The study highlights Pro-Ca and CaCl2 as promising and sustainable postharvest treatments of strawberries as a safer substitute to the traditional chemical fungicides, which also fits the current consumer demands of natural products. Additionally, the use of these treatments not only improves the quality of fruits but also leads to economic sustainability through alleviating postharvest losses.
