Li Li

Mango (Mangifera indica L.) is a commercially important fruit crop whose quality attributes are shaped by genetic background and cultivation environment, yet the relative contributions of geographic origin, climatic factors, and cultivar remain poorly resolved across China’s diverse production regions. Forty mango groups representing six major cultivars (Tainong No. 1, Jinhuang, Guifei, Guire 82, Keitt, and Eagle-mouth) were collected from four principal production provinces (Guangxi, Hainan, Sichuan, and Yunnan), spanning latitudes from 19° N to 27° N and elevations from 6 to 1668 masl. Twelve quality traits were quantified alongside nine environmental variables. PCA captured 41.2% of total variance but revealed substantial interprovincial overlap, indicating limited discriminatory power of geographic origin alone. OPLS-DA showed that mean relative humidity (VIP = 1.48) and extreme maximum temperature (VIP = 1.15) emerged as the primary environmental discriminators among the variables examined. Hierarchical clustering revealed that samples from the same province were frequently dispersed across multiple clusters, further highlighting the apparent role of cultivar-specific genetic factors. Pooled Pearson correlation analysis showed that fruit-quality variation was associated mainly with cultivar: cultivar correlated significantly with total soluble solids (r = 0.598), carotene (r = 0.535), and pectin (r = 0.525), whereas environment–quality associations were weak and exploratory, with only two nominally significant correlations (extreme maximum temperature with carotene, r = −0.332, and with moisture, r = 0.327). These findings suggest that mango fruit quality is governed predominantly by cultivar, with local microclimate and geographic provenance serving as modulating factors. Such insights offer preliminary evidence-based guidance for regional cultivar deployment and quality-oriented orchard management, particularly in cultivar selection for targeted fresh-market and processing applications.

Mango (Mangifera indica L.) is a commercially important fruit crop whose quality attributes are shaped by genetic background and cultivation environment, yet the relative contributions of geographic origin, climatic factors, and cultivar identity remain poorly resolved across China's diverse production regions. Forty mango samples representing six major cultivars (Tainong No. 1, Jinhuang, Guifei, Guire 82, Keitt, and Eagle-mouth) were collected from four principal production provinces (Guangxi, Hainan, Sichuan, and Yunnan), spanning latitudes from 19°N to 27°N and elevations from 6 to 1668 m. Twelve quality traits, including dietary fiber fractions, soluble sugars, organic acids, carotenoids, and pectin, were quantified alongside nine environmental variables. PCA captured 41.2% of total variance but revealed substantial interprovincial overlap, indicating limited discriminatory power of geographic origin alone. OPLS-DA identified mean relative humidity (VIP = 1.48) and extreme maximum temperature (VIP = 1.15) as the primary environmental discriminators. Hierarchical clustering confirmed that samples from the same province frequently dispersed across multiple clusters, underscoring the dominance of cultivar-specific genetic factors. Cultivar-level analyses revealed distinct environment-quality interaction signatures, with Guifei exhibiting the most extensive correlation network. These findings establish that mango fruit quality is governed predominantly by cultivar identity, with local microclimate and geographic provenance serving as modulating factors. Such insights offer evidence-based guidance for regional cultivar deployment and quality-oriented orchard management, particularly in cultivar selection for targeted fresh-market and processing applications.

Siraitia grosvenorii fruit, a traditional medicinal and edible plant, undergoes significant alterations in quality and bioactive composition during the dehydration process. This study investigated the effects of hot-air drying at various temperatures on the physicochemical properties, antioxidant activity, and drying kinetics of S. grosvenorii fruit. The drying process was terminated when fruit moisture content reached 15%, with corresponding drying durations of 420, 225, 144, 96, and 51 h at 40 °C, 50 °C, 60 °C, 70 °C and 80 °C, respectively. Among the ten mathematical models evaluated, the Midilli–Kucuk model provided the most accurate description of the drying kinetics of S. grosvenorii fruit. Quality analysis revealed that drying reduced the sugar/acid ratio, contents of mogrosides and ascorbic acid, while increasing total phenolic and flavonoid levels. Microstructural analysis revealed that higher temperatures increased drying rates by expanding the porosity of the pulp. Based on the retention of bioactive components and antioxidant capacity, 70 °C was identified as the optimal drying temperature. Overall, these findings suggest that oven-drying optimizes drying efficiency and ensures the retention of essential bioactive constituents in S. grosvenorii.

Mechanical damage to banana fruit during transportation leads to substantial quality loss and shortened shelf life. This study investigated the effects of different concentrations (10, 20, and 50 μM) of methyl jasmonate (MeJA) on mechanically injured banana fruits stored at 25°C for 14 days. The results showed that the 10 μM MeJA treatment was identified as optimal, delaying the respiration peak by 2 days and maintaining fruit greater firmness (95.86 N) on Day 14. It also effectively suppressed the rise in ripening index, decay rate, total soluble solids (TSS) content, and malondialdehyde (MDA) content, thereby preserving better appearance and edible quality. In addition, 10 μM MeJA enhanced antioxidant enzyme activities and strengthened the activities of enzymes associated with disease resistance. On Day 14, the activities of ascorbate peroxidase (APX) and phenylalanine ammonia‐lyase (PAL) were significantly higher than those of the control by 2.02‐ and 1.73‐fold, respectively. Meanwhile, the activities of peroxidase (POD), polyphenol oxidase (PPO), β‐1,3‐glucanase (GLU), and chitinase (CHT) were maintained at levels 48.37%, 37.30%, 13.61%, and 47.77% higher than the control, respectively, at the end of storage. This study indicated that treatment with 10 μM MeJA effectively enhanced the antioxidant ability and disease resistance of mechanically injured banana fruits, thereby maintaining fruit quality during storage and improving the storability.

Bananas are economically important fruits, but they are vulnerable to mechanical damage during harvesting and transport. This study examined the effects of methyl jasmonate (MeJA) on the cell membrane integrity and membrane lipid metabolism of wounded banana fruits after harvest. The results showed that 10 and 50 μM MeJA treatments on mechanically wounded bananas significantly delayed ripening and senescence in comparison with the control. At the end of storage, MeJA-treated groups showed a significant reduction in electrolyte leakage and malondialdehyde content, indicating that MeJA protected cell membrane integrity. MeJA also led to a significant decrease in the activity of antioxidant enzymes, including lipoxygenase, diacylglycerol kinase, and lipid phosphate phosphatase. Furthermore, MeJA reduced phospholipase (C and D), phosphatidic acid, and diacylglycerol levels, as well as slowed down the decrease in phosphatidylcholine and phosphatidylinositol contents. Compared to the control, MeJA significantly downregulated the expression of MaPLDγ, MaPLDα, and MaPLDζ. Therefore, MeJA treatment could be a reliable method to delay the senescence of harvested banana fruits subjected to mechanical wounding.

This study identified and tested fruit-isolated Metschnikowia yeasts against three major postharvest citrus pathogens, namely, Penicillium digitatum, Penicillium italicum, and Geotrichum citri-aurantii, and further evaluated the impact of FeCl₃ on the biocontrol efficiency of pulcherrimin-producing M. pulcherrima strains. Based on the characterization of the pigmented halo surrounding the colonies and the analysis of the D1/D2 domain of 26S rDNA, a total of 46 Metschnikowia sp. were screened and identified. All 46 Metschnikowia strains significantly inhibited the hyphal growth of Penicillium digitatum, Penicillium italicum, and Geotrichum citri-aurantii, and effectively controlled the development of green mold, blue mold and sour rot of citrus fruit. The introduction of exogenous FeCl₃ at certain concentrations did not significantly impact the pulcherriminic acid (PA) production of pigmented M. pulcherrima strains, but notably diminished the size of pigmented zones and the biocontrol efficacy against the three pathogens. Iron deficiency sensitivity experiments revealed that P. digitatum and P. italicum exhibited higher sensitivity compared to G. citri-aurantii, indicating that iron dependence varied among the three pathogens. These results suggested that M. pulcherrima strains, capable of producing high yields of PA, possessed great potential for use as biocontrol agents against postharvest citrus diseases. The biocontrol efficacy of these yeasts is mainly attributed to their ability to competitively deplete iron ions in a shared environment, with the magnitude of their pigmented halo directly correlating to their antagonistic capability. It is worth noting that the level of sensitivity of pathogens to iron deficiency might also affect the biocontrol effect of pulcherrimin-producing M. pulcherrima.

In this study, mango fruit (Tainong No. 1) was treated with either 0.1 mg/L 1-methylcyclopropene (1-MCP) alone or with a combination of 0.1 mg/L 1-MCP and 0.2 mM melatonin (MT). The mango fruit was then stored for 10 days at 25 °C and 85–90% relative humidity. Quality characteristics and the active oxygen metabolism of postharvest mangoes were evaluated every 2 days. Compared to untreated mango fruit, those with the treatments of 1-MCP alone or 1-MCP + MT had a better appearance and higher levels of soluble sugar, ascorbic acid, and titratable acidity. Moreover, these treatments prevented the loss of fruit firmness, successfully delayed the escalation of a* and b* values, and reduced malondialdehyde content and superoxide anion generation rate. After 10 days of storage, mango fruit treated by 1-MCP alone or 1-MCP + MT exhibited increased activities of antioxidant enzymes such as ascorbate peroxidase, catalase, superoxide dismutase, and other peroxidases; nevertheless, the two treatment protocols maintained higher mango total phenolic content only at the later stage of storage. These findings suggest that mango fruit treated with 1-MCP alone or with 1-MCP + MT improves the quality characteristics and antioxidant activities. Moreover, compared to 1-MCP treatment alone, 1-MCP + MT-treated mangoes exhibited higher quality and a stronger regulation of active metabolism during storage.

The banana quality evaluation system is not sufficiently mature in China and cannot meet the demand of producing high-quality processed banana products. In order to screen banana varieties suitable for low-temperature vacuum frying and extend the banana deep processing industry chain, banana slices from 15 varieties planted in China were prepared by low-temperature vacuum-frying (VF) technology in the present study. After factor analysis on 20 indicators of sensory, flavor, nutritional and processing quality from different varieties of banana slices, comprehensive quality evaluation models were constructed for banana slices. It was concluded that Meishijiao No. 1 had the highest overall score among the 15 banana varieties; hence, it was deemed suitable for processing. Meanwhile, in order to investigate the difference between flavor substances in banana slices before and after processing, a flavor histology study was conducted with solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography coupled to time-of flight mass spectrometry (GC×GC-TOFMS). It was found that the content differences of 2,3-pentanedione, hexanal and pentanal may cause the weakened fruitiness and the increased oil flavor of banana taste.