Applying biochar to tomato cultivation presents a beneficial strategy that can enhance both yield and fruit quality, crucial for sustainable agricultural practices. However, a review of the existing literature on the effects of biochar indicates a significant variability in outcomes, suggesting the need for a more nuanced understanding of biochar application in relation to soil and biochar conditions. This study conducts a meta-analysis on the literature published before March 2024 to investigate the impacts of biochar properties, agricultural practices, and soil properties on the yield and fruit quality of tomato. The results indicated that biochar application significantly increased tomato yield by 29.55%, total soluble solids (TSS) by 4.28%, and vitamin C (VC) by 6.77% compared to control treatments without biochar, especially at higher application rates. However, the benefits may wane over time due to biochar aging in the soil, requiring periodic replenishment. The type of biochar and pyrolysis temperature, particularly wood and straw biochar pyrolyzed at 401–500 °C, were found to be most effective for boosting yield and quality. Additionally, initial soil properties, including soil organic matter, pH, and nutrient levels, interact with biochar to influence outcomes, with biochar being particularly beneficial for soils with a high bulk density and low soil organic matter (SOM) or nutrient deficiencies. This study underscores the potential of biochar as a multifaceted strategy in tomato cultivation, enhancing not only yield but also the nutritional value of the fruit, while simultaneously improving soil health.

Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus of the Geminiviridae family, causes leaf curl disease of tomato that significantly affects tomato production worldwide. SA (salicylic acid), JA (jasmonic acid) or the JA mimetic, COR (coronatine) applied exogenously resulted in improved tomato resistance against TYLCV infection. When compared to mock treated tomato leaves, pretreatment with the three compounds followed by TYCLV stem infiltration also caused a greater accumulation of H₂O₂. We employed RNA-Seq (RNA sequencing) to identify DEGs (differentially expressed genes) induced by SA, JA, COR pre-treatments after Agro-inoculation of TYLCV in tomato. To obtain functional information on these DEGs, we annotated genes using gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) databases. Based on our comparative analysis, differentially expressed genes related to cell wall metabolism, hormone signaling and secondary metabolism pathways were analyzed in compound treated samples. We also found that TYLCV levels were affected in SlNPR1 and SlCOI1 silenced plants. Interestingly, compared to the mock treated samples, SA signaling was hyper-activated in SlCOI1 silenced plants which resulted in a significant reduction in viral titer, whereas in SINPR1 silencing tomato plants, there was a 19-fold increase in viral load. Our results indicated that SA, JA, and COR had multiple impacts on defense modulation at the early stage of TYLCV infection. These results will help us better understand SA and JA induced defenses against viral invasion and provide a theoretical basis for breeding viral resistance into commercial tomato accessions.

Tomato leaf mold caused by Cladosporium fulvum (C. fulvum) is a serious fungal disease which results in huge yield losses in tomato cultivation worldwide. In our study, we discovered that ROS (reactive oxygen species) burst was triggered by C. fulvum treatment in tomato leaves. RNA-sequencing was used to identify differentially expressed genes (DEGs) induced by C. fulvum inoculation at the early stage of invasion in susceptible tomato plants. Gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were used to annotate functions of DEGs in tomato plants. Based on our comparative analysis, DEGs related to plant-pathogen interaction pathway, plant hormone signal transduction pathway and the plant phenylpropanoid pathway were further analyzed. Our results discovered that a number of core defense genes against fungal invasion were induced and plant hormone signal transduction pathways were impacted by C. fulvum inoculation. Further, our results showed that SA (salicylic acid) and ABA (abscisic acid) contents were accumulated while JA (jasmonic acid) content decreased after C. fulvum inoculation in comparison with control, and quantitative real-time PCR to detect the relative expression of genes involved in SA, ABA and JA signaling pathway further confirmed our results. Together, results will contribute to understanding the mechanisms of C. fulvum and tomato interaction in future.

This study investigates the impact of dynamically adjusting the potassium-to-calcium ratio (molar ratio) in nutrient solutions used on cherry tomatoes at different growth stages (seedling, flowering and fruit setting, and maturity) to enhance fruit appearance, nutritional quality, and mineral content. By focusing on the ‘Saopolo’ variety, 17 treatments were implemented, each involving a specific potassium-to-calcium ratio in the nutrient solutions applied during the seedling, flowering and fruit setting, and fruiting stages. The aim was to optimize the nutrient solution formula and enhance fruit quality. Fruit quality parameters were assessed at the initial maturity stage across various treatments, encompassing commodity quality (fruit stalk length, fruit shape index, and fruit hardness), taste quality (total soluble sugar, titratable acid content, and sugar-acid ratio), nutritional quality (vitamin C (Vc), soluble protein, and lycopene content), antioxidant quality (total phenol and flavonoid content), as well as comprehensive quality (soluble solids content). Principal component analysis was conducted on these parameters. Additionally, mineral element levels in fruits were analyzed at different developmental stages (white ripe, color transition, and mature stages). When tomato plants were treated with nutrient solutions containing varying potassium-to-calcium ratios at different growth stages, observations revealed distinct outcomes in the first fruit cluster. T15 (seedling stage (A): 0.5 times standard nutrient solution; flowering and fruit-setting stage (B): potassium-to-calcium = 1.6:1; fruiting stage (C): potassium-to-calcium = 2.1:1) exhibited the highest fruit firmness (1.54 kg·cm⁻²), while T14 (A; B (K:Ca = 1.6:1); C (K:Ca = 2.0:1)) elevated levels of total soluble sugars (6.59%), titratable acidity (0.74%), soluble proteins (2.79 mg·g⁻¹), and total phenolics (2.56 mg·g⁻¹). T13 (A; B (K:Ca = 1.6:1); C (K:Ca = 1.9:1)) demonstrated superior soluble solids (5.9%), lycopene (32.09 µg·g⁻¹), and flavonoid contents (0.77 mg·g⁻¹), whereas T12 (A; B (K:Ca = 1.6:1); C (K:Ca = 1.8:1)) showcased the highest sugar–acid ratio (12.63) and soluble solids content (5.9%). Notably, T8 (A; B (K:Ca = 1.5: 1); C (K:Ca = 1.9:1)) exhibited the highest Vc content (10.03 mg·100 g⁻¹). Mineral element analysis indicated that an increased potassium-to-calcium ratio in the nutrient solution during various growth stages enhanced phosphorus and potassium uptake by the fruits but hindered the absorption of nitrogen, calcium, magnesium, and iron. In summary, employing half the standard nutrient solution dosage during the seedling stage, utilizing a potassium-to-calcium ratio of 1.6:1 in the nutrient solution at the flowering and fruit setting stage, and applying nutrient solution T13 with a potassium-to-calcium ratio of 1.9:1 during the fruit-bearing phase, optimally coordinates fruit nutrient accrual and enhances flavor quality. These findings support the use of stage-specific nutrient modulation to improve cherry tomato quality in controlled-environment agriculture.

Pepper (Capsicum annuum L.), an annual herbaceous plant in the Solanaceae family, possesses significant edible and medicinal value. Studies have shown that there are significant differences in the plant chemical constituents and antioxidant activity among different colored peppers, but there have been fewer studies on the relationship between pigment content, plant chemical constituents and antioxidant activity in peppers. Therefore, this study divided twenty pepper accessions of pepper materials into four categories based on color changes and measured the bioactive compounds, pigment content and antioxidant activity of these four types of peppers at different maturity stages and conducted correlation analysis and principal component analysis (PCA). The results showed that yellow pepper cultivars had higher levels of vitamin C (Vc), and Class IV (purple-to-red transitioning pepper cultivars) had higher total phenolic content (TPC), total flavonoid content (TFC), and anthocyanin content in the early fruit stage. Correlation analysis showed that Class IV (purple-to-red transitioning pepper cultivars) had higher levels of bioactive compounds and antioxidant capacity. The antioxidant content in immature fruits was high, but decreased as the fruits matured. This study focuses on pepper-derived bioactive compounds and their antioxidant activity, providing a scientific basis for developing natural antioxidant products, expanding pepper resource utilization, and guiding pepper variety selection and cultivation management.