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Compost residue enriches soil health with the potential to enhance plant metabolism and hormonal balance, but has not yet been studied. A study was performed to determine how prevailing compost residue induces tomato (Solanum lycopersicum 'Scotia') plant morpho-physiology, phytohormones, and secondary metabolites. Plants were grown in soils with a previous history of annual (AN) and biennial (BI) compost amendments. The controls were soil without compost (C) amendment and municipal solid waste compost (MSWC) alone. The MSWC- and AN-plants had similar and significantly (p < 0.05) highest growth and photosynthetic activities compared to the BI- or C-plants. Total phenolics and lipid peroxidase activity were significantly (p < 0.001) high in BI-plants, while hydrogen peroxide and antioxidant capacity were significantly (p < 0.001) high in AN-plants. MSWC-plants recorded the highest cis-abscisic acid, followed by AN-, and then BI- and C-plants. Cis-zeatin, trans-zeatin, and isopentenyladenine ribosides were detected in the MSWC- and AN-plants but not in the BI- or C-plants. Furthermore, gibberellins GA53, GA19, and GA8 were high in the MSWC-plants, but only GA8 was detected in the AN plants and none in the others. Besides, MSWC plants exhibited the highest content of 1-aminocyclopropane-1-carboxylic acid. Conjugated salicylic acid was highest in the BI-plants, while jasmonic acid-isoleucine was highest in MSWC-plants and C plants. In conclusion, prevailing compost chemical residues upregulate plant growth, phytohormones, and metabolic compounds that can potentially increase plant growth and abiotic stress defense. Future work should investigate the flow of these compounds in plants under abiotic stress. [ABSTRACT FROM AUTHOR]

Purpose: Problem-based learning (PBL), a relatively novel teaching and learning process in horticulture, was investigated. Proper application of PBL can potentially create a learning context that enhances student learning. Design/Methodology/Approach: Students worked on two complex ill-structured problems: (1) to produce fresh baby greens for a 4-week catering event and (2) to produce seedlings for a grower. Data collected were analyzed by the concurrent method and presented as case studies. Findings: Students developed positive attitudes through active engagement. Their presentations and reports demonstrated leadership roles, critical thinking and conflict management. Practical professional, social and affective skills were developed through production of 5 kg baby greens, and 2500 vegetable seedlings. Successes and limitations were identified. Theoretical Implication: The quality of the PBL problem is critical for the stimulation and elaboration of prior knowledge, development of epistemic curiosity and the relevant semantic framework. These are motivators that inspire effective learning. Practical Implication: Cognitive and emotional intelligence skills are realized by trusting the PBL process, identifying enhancers and inhibitors. Enhancement of creativity, social and employability skills manifest through challenges that help to develop for the "whole". Originality/Value: In the horticulture industry, stakeholders interact with each other and the agro-ecological system. Consequently, competencies in production and emotional intelligence are invaluable.

This study explores the suitability of different biomass feedstocks for biochar production and their effects on soil health and crop yield. Two planting seasons were conducted, involving cucumber as the test crop and eleven treatments combining biochar and poultry manure. Soil analysis revealed initial soil conditions with high sand content and low pH. Poultry manure and biochar exhibited pH, organic carbon, and nutrient level variations. Significant differences in cucumber growth and yield were observed, with the longest vine length in plots treated with palm kernel husk biochar and poultry manure. Residual effects in the second planting season displayed similar trends. Soil pH, organic carbon, and total nitrogen remained consistent between seasons, while available phosphorus increased significantly in plots amended with goat manure biochar and poultry manure. Calcium, magnesium, potassium, and sodium contents also varied. Fruit length, weight, and yield were significantly improved by biochar treatments, with the combination of palm kernel husk biochar and poultry manure yielding the highest fruit weight. Correlation and structural equation analyses (p < 0.05) highlighted the relationships between plant characteristics, soil properties, and fruit indices, emphasizing the importance of nitrogen and phosphorus in supporting fruit development. The study suggests that biochar application enhances soil nutrients, crop growth, and fruit yields while reducing reliance on chemical fertilizers. It recommends considering biochar for land reclamation and as an alternative to traditional fertilizers, supported by appropriate regulations. [ABSTRACT FROM AUTHOR]

Coffee is among the most widely consumed beverages worldwide, leading to the annual generation of substantial quantities of spent coffee grounds (SCGs). This study explored the influence of fabrication methods on the properties and potential applications of the resulting biocarbon materials. Dry methods (torrefaction at 270 °C and slow pyrolysis at 500 °C) and wet methods (hydrothermal carbonization HTC at 210 °C and hydrothermal liquefaction HTL at 270 °C) were employed to fabricate SCG-based biochar and hydrochar, respectively. The carbonization degree followed the order of slow pyrolysis > HTL > HTC ≈ torrefaction, yielding significant differences in energy properties, elemental composition, morphology, and surface functionality. Slow pyrolysis biochar was suitable for energy applications due to a similar fuel ratio as and higher heating value than semianthracite coal. For agricultural applications, SCG biochar produced through dry methods could be utilized to mitigate acidic soil conditions, whereas HTC hydrochar, with its elevated surface area and porosity, could enhance soil microbiological diversity and water-holding capacity, as well as benefit environmental applications such as wastewater remediation. In summary, the findings of this study are anticipated to inform decision-making processes concerning sustainable waste management of SCGs and the exploration of carbon-based materials applications across diverse sectors. [ABSTRACT FROM AUTHOR]