ABSTRACT
Cascade cropping systems (CCS) utilize leachate from a primary crop to grow secondary crops and enhance the efficient use of water and fertilizers in areas with scarce water resources. A preliminary study investigated the effect of melatonin in a cascade cropping system to potentially improve plant tolerance to abiotic stresses. This study aimed to cultivate Salicornia fruticosa in this cropping system to reduce nutrient discharge and assess the impact of exogenous melatonin on Salicornia growth and quality. The CCS included a primary crop of Salicornia grown in an agro-industrial compost or peat. Leachates from these media were used to cultivate the same plant once again in a floating system under four treatments: compost leachate (T1), peat leachate (T2), 100% nutrient solution (NS) (T3), 50% NS (T4) strength. Four concentrations of exogenous melatonin were applied in foliar spray: 0, 100, 200, and 400 µM. Melatonin application increased yield, with the highest values observed when plants were grown in T1. Water use efficiency was also maximized in T1 and with both 200 and 400 µM melatonin applications. The highest nitrogen use efficiency was achieved in plants grown in peat leachate. The lipid membrane damage was assessed revealing that plants grown in compost leachate exhibited the lowest MDA values regardless of melatonin concentrations. The accumulation of some antinutritional compounds (nitrate, oxalate, and sodium) were the highest in those plants grown in compost leachate. Overall, shoots grown in peat leachate exhibited the best phytochemical profile (total phenol content, total flavonoids, and antioxidant capacity), with peak values in plants treated with 200 µM melatonin. These findings suggest that S. fruticosa can be effectively cultivated using leachate from a previous crop in a floating system and that exogenous melatonin application enhances the yield and nutritional quality of Salicornia shoots.
ABSTRACT
BACKGROUND: Previous research has established that using high-quality planting material during the early phase of vegetable production significantly impacts success and efficiency, leading to improved crop performance, faster time to harvest and better profitability. In the present study, we conducted a global analysis of vegetable seedlings and transplants, providing a comprehensive overview of research trends in seedling and transplant production to enhance the nutritional quality of vegetables. RESULTS: The analysis involved reviewing and quantitatively analysing 762 articles and 5248 keywords from the Scopus database from 1971 to 2022. We used statistical, mathematical and clustering tools to analyse bibliometrics and visualise the most relevant research topics. A visualisation map was generated to identify the evolution of keywords used in the articles, resulting in five clusters for further analysis. Our study highlights the importance of the size of seed trays for the type of crop, the mechanical seeder used and the greenhouse facilities to produce desirable transplants. We identified grafting and light-emitting diode (LED) lighting technology as rapidly expanding technologies in vegetable seedlings and transplant production used to promote plant qualitative profile. CONCLUSION: There is a need for sustainable growing media to optimise resources and reduce input use. Thus, applying grafting, LED artificial lighting, biostimulants, biofortification and plant growth-promoting microorganisms in seedling production can enhance efficiency and promote sustainable vegetable nutritional quality by accumulating biocompounds. Further research is needed to explore the working mechanisms and devise novel strategies to enhance the product quality of vegetables, commencing from the early stages of food production. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.