Mature Fruit Research Articles

Comparison Classification Of Tomatoes Ripeness Based On RGB, HSV And CMYK Colors Based On Correlation Coefficient

This article discusses the classification of tomato fruit maturity based on color space. Several studies have been conducted to measure maturity levels using RGB and HSV color spaces. In this article, researchers classify the ripeness of tomatoes using the CMYK color space, which researchers have never done before. Next, the classification results of the CMYK color space are compared with the RGB and HSV color spaces. The CMYK color space is a secondary color commonly seen by the human eye. CMYK colors are colors produced from a combination of RGB colors. Comparison of classification results based on CMYK, RGB, and HSV color spaces was carried out using the correlation coefficient and mean square error (MSE). The correlation coefficient is a method that is often used to measure the similarity between 2 images, where the closer to 0 the correlation value, the better

Long-term effects of silver nanoparticles and mineral nutrition components on the photosynthetic processes, chloroplast ultrastructure and productivity of Solanum lycopersicum plants

The effects of silver nanoparticles (AgNPs), both alone and in combination with mineral nutrients, on the growth and photosynthesis of Solanum lycopersicum plants during ontogeny were studied. The experiment involved weekly applications of 10 μmol of AgNPs for 15 weeks in a greenhouse over a summer period. A comprehensive characterization of the AgNPs was performed via TEM, ESI/EELS, and zeta potential measurements before and throughout the experiment. The activity of PSII, stomatal conductivity, photosynthesis, transpiration and respiration rates were measured, and the photosynthetic pigments, chloroplast ultrastructure, and dry and fresh masses of leaves, roots, and fruits were assessed. The results indicated that combining AgNPs with mineral nutrients increased PSII activity and the photosynthesis rate and altered the chloroplast ultrastructure. However, the use of mineral nutrients or AgNPs alone did not induce these changes. Atomic absorption spectrometry detected AgNPs in all the plant organs except the fruits. The highest fruit yield was associated with Veni Prisma®, a commercial product containing colloidal silver, which also caused desynchronized fruit maturation. This study hypothesizes that the synergistic effect of AgNPs and mineral nutrients enhances silver accumulation in chloroplasts, improving light utilization and photosynthetic efficiency, particularly under low light, thus increasing fruit quantity and dry mass. Conversely, long-term use of AgNPs alone was accompanied by silver accumulation outside the chloroplasts and did not lead to increased photosynthesis or an increase in fresh fruit mass.

Evaluation of fatty acid composition and antimicrobial activity of supercritical fluid extract of Rubus ulmifolius Schott fruits

In this study, we continue our research on Rubus ulmifolius Schott extracts obtained by supercritical fluid extraction (SFE) using CO2 as solvent. Extraction experiments were carried out at pressures of 300 bar and a temperature of 40 °C, SFE [300:40], on mature fruits of R. ulmifolius. The fatty acid (FA) profile of extracts was assessed by reversed-phase HPLC-DAD/ELSD analysis. The most represented fatty acids in the extract were linoleic acid (386 mg/g), oleic acid (210 mg/g), linolenic acid (112 mg/g), palmitic acid (48 mg/g), and stearic acid (40 mg/g). SFE extraction showed a total FA amount of 795.8 mg/g of dry weight. The chemical and biological characteristics of this extract were compared with those obtained with different extraction methods. Following the diffusion-susceptibility test, three fruit extracts, SFE [300:40], Sx, and MEtOH, didn’t show an inhibition profile against Streptococcus mutans. Kirby-Bauer analysis showed only the methanolic extract demonstrated antimicrobial activity with 11-mm inhibition diameter.

Comparison of Protective Effects of Polyphenol-Enriched Extracts from Thinned Immature Kiwifruits and Mature Kiwifruits against Alcoholic Liver Disease in Mice.

Alcoholic liver disease (ALD) is regarded as one of the main global health problems. Accumulated evidence indicates that fruit-derived polyphenols can lower the risk of ALD, this attributed to their strong antioxidant capacities. Thinned immature kiwifruits (TIK) are the major agro-byproducts in the production of kiwifruits, which have abundantly valuable polyphenols. However, knowledge about the protective effects of polyphenol-enriched extract from TIK against ALD is still lacking, which ultimately restricts their application as value-added functional products. To promote their potential applications, phenolic compounds from TIK and their corresponding mature fruits were compared, and their protective effects against ALD were studied in the present study. The findings revealed that TIK possessed extremely high levels of total phenolics (116.39 ± 1.51 mg GAE/g DW) and total flavonoids (33.88 ± 0.59 mg RE/g DW), which were about 7.4 times and 4.8 times greater than those of their corresponding mature fruits, respectively. Furthermore, the level of major phenolic components in TIK was measured to be 29,558.19 ± 1170.58 μg/g DW, which was about 5.4 times greater than that of mature fruits. In particular, neochlorogenic acid, epicatechin, procyanidin B1, and procyanidin B2 were found as the predominant polyphenols in TIK. In addition, TIK exerted stronger in vitro antioxidant and anti-inflammatory effects than those of mature fruits, which was probably because of their higher levels of polyphenols. Most importantly, compared with mature fruits, TIK exhibited superior hepatoprotective effects on alcohol-induced liver damage in mice. The administration of polyphenol-enriched extract from TIK (YK) could increase the body weight of mice, reduce the serum levels of ALP, AST, and ALT, lower the levels of hepatic TG and TC, and diminish lipid droplet accumulation and hepatic tissue damage. In addition, the treatment of YK could also significantly restore the levels of antioxidant enzymes (e.g., SOD and CAT) in the liver and lower the levels of hepatic proinflammatory cytokines (e.g., IL-6, IL-1β, and TNF-α), indicating that YK could effectively ameliorate ALD in mice by reducing hepatic oxidative stress and hepatic inflammation. Collectively, our findings can provide sufficient evidence for the development of TIK and their extracts as high value-added functional products for the intervention of ALD.

Identification of the Optimal Quantitative RT-PCR Reference Gene for Paper Mulberry (Broussonetia papyrifera).

Paper Mulberry (Broussonetia papyrifera) possesses medicinal, economic, and ecological significance and is extensively used for feed production, papermaking, and ecological restoration due to its ease of propagation, rapid growth rate, and strong stress resistance. The recent completion of the sequencing of the Paper Mulberry genome has prompted further research into the genetic breeding and molecular biology of this important species. A highly stable reference gene is essential to enhance the quantitative analysis of functional genes in Paper Mulberry; however, none has been identified. Accordingly, in this study, the leaves, stems, roots, petioles, young fruits, and mature fruits of Paper Mulberry plants were selected as experimental materials, and nine candidate reference genes, namely, α-TUB1, α-TUB2, β-TUB, H2A, ACT, DnaJ, UBQ, CDC2, and TIP41, were identified by RT-qPCR. Their stability was assessed using the geNorm, Normfinder, Delta Ct, BestKeeper, and RefFinder algorithms, identifying ACT and UBQ as showing the greatest stability. The expression of BpMYB090, which regulates the production of trichomes, was examined in the leaves of plants of the wild type (which have more trichomes) and mutant (which have fewer trichomes) at various developmental stages to validate the results of this study. As a result, their identification addresses a critical gap in the field of Paper Mulberry research, providing a solid foundation for future research that will concentrate on the characterization of pertinent functional genes in this economically valuable species.

Genomes of autotetraploid wild and cultivated Ziziphus mauritiana reveal polyploid evolution and crop domestication.

Indian jujube (Ziziphus mauritiana) holds a prominent position in the global fruit and pharmaceutical markets. Here, we report the assemblies of haplotype-resolved, telomere-to-telomere genomes of autotetraploid wild and cultivated Indian jujube plants using a two-stage assembly strategy. The generation of these genomes permitted in-depth investigations into the divergence and evolutionary history of this important fruit crop. Using a graph-based pan-genome constructed from eight monoploid genomes, we identified structural variation (SV)-FST hotspots and SV hotspots. Gap-free genomes provide a means to obtain a global view of centromere structures. We identified presence-absence variation-related genes in four monoploid genomes (cI, cIII, wI, and wIII) and resequencing populations. We also present the population structure and domestication trajectory of the Indian jujube based on the resequencing of 73 wild and cultivated accessions. Metabolomic and transcriptomic analyses of mature fruits of wild and cultivated accessions unveiled the genetic basis underlying loss of fruit astringency during domestication of Indian jujube. This study reveals mechanisms underlying the divergence, evolution, and domestication of the autotetraploid Indian jujube and provides rich and reliable genetic resources for future research.

Detection of Camellia oleifera fruit maturity in orchards based on modified lightweight YOLO

Fruit maturity is the main factor affecting the quality and yield of Camellia oil. At present, accurate and efficient detection of the maturity level of Camellia oleifera fruits in orchards and enabling selective picking for harvesting robots is a crucial issue. Aiming at the challenge of low detection efficiency of Camellia oleifera fruit maturity and complex object detection models that are difficult to deploy to Camellia oleifera selective harvesting robots, a modified lightweight You Only Look Once model (YOLO-LM) based on YOLOv7-tiny is proposed. Specifically, three Criss-Cross Attention (CCA) modules are introduced to the backbone network to reduce the influence of leaves and branches occlusion as well as mutual occlusion between fruits. Then, the Adaptively Spatial Feature Fusion (ASFF) module is applied as the head to solve the limitation of inconsistency across different feature scales on the feature pyramid. Furthermore, the GSConv is introduced to replace the standard convolution of the Neck network to enable the model to simultaneously preserve model accuracy and reduce model complexity. Experiment results demonstrate that the precision, recall, mAP@0.5, parameters, FLOPs, and model size of YOLO-LM reached 93.96 %, 93.32 %, 93.18 %, 10.17 million, 19.46 G, and 19.82 MB, which outperformed YOLOv3, Faster R-CNN (VGG16), Faster R-CNN (ResNet50), YOLOv4, and YOLOv5m. Compared to YOLOv3-tiny, YOLOv4-tiny, YOLOv5s, YOLOv7-tiny, and YOLOv8s, the mAP@0.5 of YOLO-LM increased by 6.24 %, 6.11 %, 2.52 %, 2.45 %, and 0.57 %, respectively. Meanwhile, the parameters and model size of YOLO-LM are slightly higher than that of YOLOv3-tiny, YOLOv4-tiny, YOLOv5s and YOLOv7-tiny, and significantly lower than that of YOLOv8s. In addition, the detection heatmaps of YOLOv7-tiny and YOLO-LM demonstrate these optimization operations contribute to the enhanced performance of maturity detection for Camellia oleifera fruits within natural orchard environments. Overall, the YOLO-LM model can be used for the maturity detection of Camellia oleifera fruits in orchards, which is expected to provide theoretical reference for orchard yield estimation, growth monitoring, planting management optimization and the development of Camellia oleifera selective harvesting robots.

Mature fruits of Gliricidia sepium and Leucaena leucocephala plants have potential as inexpensive protein and mineral supplements for ruminants

Mature fruits of Gliricidia sepium and Leucaena leucocephala plants have potential as inexpensive protein and mineral supplements for ruminants

Soil moisture content estimation of drip-irrigated citrus orchard based on UAV images and machine learning algorithm in Southwest China

Soil moisture content (SMC), as a pivotal component in the energy and matter exchange processes within the soil-plant-atmosphere continuum, plays a crucial role in surface water dynamics, energy fluxes, and carbon cycling within ecosystems. The development of remote sensing technology has offered new perspectives for monitoring soil moisture at regional scales. Unmanned aerial vehicles (UAV) equip with multispectral have distinct advantages for vegetation monitoring, including rapidity and cost-effectiveness, which has superior applicability and practicality. Therefore, in a 5a "Daya" late-maturing citrus orchard, the vegetation index (VI) and texture feature (TF) information of citrus canopy based on UAV multi-spectral images were extracted, and soil and plant analyzer development (SPAD) of citrus was collected. These different data sources were integrated into the framework of the random forest algorithm (RF) and genetic algorithm-optimized random forest (GA-RF) to evaluate the accuracy of surface SMC (SSMC) estimation in citrus orchard. The Biswas model was utilized to simulate the root zone SMC (RSMC). The spatiotemporal variations of SMC in citrus orchard were analyzed, and the potential of low-cost sensor-equipped drones in rapidly acquiring spatial and temporal distribution information of SMC at a large regional scale was explored. The results indicated that the GA-RF models outperformed the RF models in estimating citrus orchard SMC (with R2 ranging from 0.502 to 0.949 and RMSE ranging from 0.552 % to 3.166 % for GA-RF, compared to R2 ranging from 0.430 to 0.936 and RMSE ranging from 0.587 % to 3.449 % for the RF). The GA-RF models using VI+SPAD as inputs exhibited the best performance for SMC at depths of 5 cm, 10 cm, 20 cm and 40 cm (SMC5, SMC10, SMC20 and SMC40) across citrus growth stages (R2 ranging from 0.793 to 0.949 at 5 cm, R2 ranging from 0.702 to 0.938 at 10 cm, R2 ranging from 0.714 to 0.927 at 20 cm). In bud bust to flowering, young fruit and fruit maturation stages (stage Ⅰ, ⅠⅠ and ⅠⅤ), all models demonstrated good accuracy in estimating SMC at depth of 10 cm (R2 ranging from 0.567 to 0.908 in stage Ⅰ, with R2 ranging from 0.681 to 0.916 in stage ⅠⅠ and R2 ranging from 0.579 to 0.938 in stage ⅠⅤ). In fruit expansion stage (stage III), the models performed best in predicting SMC5 (R2 ranging from 0.698 to 0.861). The Biswas model was constructed to simulate SMC40 by utilizing the inverted SMC10 and SMC20, thereby generating spatiotemporal distribution maps of SMC at different depths in citrus orchard. The SSMC was susceptible to environmental factors, exhibiting significant spatiotemporal heterogeneity. In summary, this study illustrated that the integration of multiple data sources into GA-RF enhanced the estimation performance of SMC at different growth stages of late-maturing citrus orchard in the Southwest China. Additionally, it enabled the rapid and efficient monitoring of spatiotemporal variations in SMC, providing an effective method and practical foundation for precision irrigation and improved water use efficiency.

Methyl jasmonate and salicylic acid treatment changes the nutritional quality, antioxidant profile and gene expression of postharvest blackberry fruit

Blackberry fruit is rich in various nutrients and has strong antioxidant activity. However, these fruit are soft, juicy, prone to decay and spoilage, and not suitable for storage. To ensure the quality of blackberry fruit and extend its shelf life, this study used methyl jasmonate (MJ), salicylic acid (SA), or MJ+SA to treat mature blackberry fruit after harvesting. And measure the fruit appearance indicators, antioxidant contents, antioxidant enzyme activities, and related gene expression levels stored at 4 °C for different durations. The results showed that the MJ, SA, and the combination of MJ+SA treatments could slow fruit softening by increasing antioxidant contents and antioxidant enzyme activities, with MJ+SA having the greatest effect on the postharvest treatment of blackberry. Compared with those in the control, the DPPH radical scavenging capacity, total phenol and flavonoid contents, and antioxidant enzyme (POD, GSH, and SOD) activities were increased in three hormone treatment groups. Moreover, the expression levels of key genes involved in flavonoid and phenol compound synthesis were upregulated in all the postharvest treatment groups. There was a positive correlation between the contents of total phenol and flavonoid and between their related structural enzyme-encoding genes and transcription factors. This study lays the foundation for further exploration of hormone application for prolonging the shelf life and changing in the antioxidant activity of blackberry fruit.

Gene expression associated with chlorophyll degradation and color transformation in a spontaneous bud mutation of navel orange

Color mutations on citrus skin are a common occurrence and can serve as indicators of fruit maturation in citrus. In this study, a new early maturing navel orange cultivar, Lei Zao 1 Hao (MT), was identified as a spontaneous bud mutation from the Leibo Navel Orange (WT). To assess the differences between these two cultivars, the coloration of the fruit, the sugar content, and the levels of acid were examined throughout the ripening process. The study findings revealed that over the course of the fruit's development, the external peel color progressively turned orange. MT exacerbated the decline in H° while increasing L*, a*, and b*, and the chlorophyll level of the MT peel was continuously lower than that of WT, which coincided with a decrease in chlorophylls a and b. Compared to WT, MT had higher expression levels of genes linked to chlorophyll degradation, including CitCLH, CitNYC1, CitPPH, CitPAO, CitCAB1, and CitCAB2. The elevated expression of these genes in MT may potentially be associated with the initial color transformation process. In addition, the MT accelerated the accumulation of TSS and total sugar, especially before the 189 DAF of ripening. In short, ‘Lei Zao 1 Hao’ is a new option of navel orange available with extremely early maturity and a higher sugar content.

Mapping and transcriptomic profiling reveal that the KNAT6 gene is involved in the dark green peel colour of mature pumpkin fruit (Cucurbita maxima L.).

We identified a 580bp deletion of CmaKNAT6 coding region influences peel colour of mature Cucurbita maxima fruit. Peel colour is an important agronomic characteristic affecting commodity quality in Cucurbit plants. Genetic mapping of fruit peel colour promotes molecular breeding and provides an important basis for understanding the regulatory mechanism in Cucurbit plants. In the present study, the Cucurbita maxima inbred line '9-6' which has a grey peel colour and 'U3-3-44' which has a dark green peel colour in the mature fruit stage, were used as plant materials. At 5-40days after pollination (DAP), the contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids in the 'U3-3-44' peels were significantly greater than those in the '9-6' peels. In the epicarp of the '9-6' mature fruit, the presence of nonpigmented cell layers and few chloroplasts in each cell in the pigmented layers were observed. Six generations derived by crossing '9-6' and 'U3-3-44' were constructed, and the dark green peel was found to be controlled by a single dominant locus, which was named CmaMg (mature green peel). Through bulked-segregant analysis sequencing (BSA-seq) and insertion-deletion (InDel) markers, CmaMg was mapped to a region of approximately 449.51kb on chromosome 11 using 177 F2 individuals. Additionally, 1703 F2 plants were used for fine mapping to compress the candidate interval to a region of 32.34kb. Five coding genes were in this region, and CmaCh11G000900 was identified as a promising candidate gene according to the reported function, sequence alignment, and expression analyses. CmaCh11G000900 (CmaKNAT6) encodes the homeobox protein knotted-1-like 6 and contains 4 conserved domains. CmaKNAT6 of '9-6' had a 580bp deletion, leading to premature transcriptional termination. The expression of CmaKNAT6 tended to increase sharply during the early fruit development stage but decrease gradually during the late period of fruit development. Allelic diversity analysis of pumpkin germplasm resources indicated that the 580bp deletion in the of CmaKNAT6 coding region was associated with peel colour. Subcellular localization analysis indicated that CmaKNAT6 is a nuclear protein. Transcriptomic analysis of the inbred lines '9-6' and 'U3-3-44' indicated that genes involved in chlorophyll biosynthesis were more enriched in 'U3-3-44' than in '9-6'. Additionally, the expression of transcription factor genes that positively regulate chlorophyll synthesis and light signal transduction pathways was upregulated in 'U3-3-44'. These results lay a foundation for further studies on the genetic mechanism underlying peel colour and for optimizing peel colour-based breeding strategies for C. maxima.

Microfluidic paper-based analytical devices for simple and nondestructive durian fruit maturity assessment

Accurately predicting durian maturity is a critically unresolved worldwide issue. Farmers currently determine durian ripeness based on their own observation and experience leading to inconsistencies in harvest timing. This reliance on human judgment often results in premature or overripe harvests, impacting fruit quality, yield, and market value. Existing technological solutions, such as sensors are often complex and require specialized expertise, hindering their adoption by farmers and consumers. Developing sensors that can accurately measure durian ripeness without damaging the fruit, are easy to use, and affordable remains a challenge. We introduce a microfluidic paper-based analytical device (μPAD) for on-site, safe matching to meet the demands of durian maturity evaluation. The μPAD automatically collected peduncle fluid without destroying the durian fruit for dual detection of total sugar and amino acid. For determining total sugar including sucrose, glucose, and fructose, several enzymatic steps were reduced to a single step of invertase for sucrose hydrolysis before total reducing sugar was measured using gold nanoparticle (AuNP) generation. Kinetics study of invertase on the μPAD showed Vmax and Km values of 1.42 mM min−1 and 2.17 mM, respectively, that agreed with the direct study of sucrose conversion. To increase device reliability, amino acid was also simultaneously measured with sugar using the simple ninhydrin test with the addition of SnCl2. The developed sensor provided LODs of 3.50, 3.10, 3.30 μM, and 0.02 mg mL−1 for glucose, fructose, sucrose, and amino acid respectively. The μPADs were able to nondestructively discriminate between the mature and immature durians, showing high linear correlation with the standard dry weight method. The development of this μPAD technology has the potential to revolutionize durian cultivation practices, reduce post-harvest losses, and enhance the overall sustainability and profitability of the durian value chain, and can be further developed for maturity tests of other fruits.

Thrips (Thysanoptera: Terebrantia) in Nectarine Orchards in North-East Spain: Species Diversity and Fruit Damage.

Thrips constitute one of the main nectarine pests, with damage either in flowering or before harvesting (silvering). Several species are associated with damage to flowers, but Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is the main species associated with summer damage in Europe. Tree canopies of nectarine orchards under organic and integrated management were sampled in Lleida and Girona at four key moments of the season (bud burst, full flowering, fruit setting stage, and colorization of the fruit) during 2021 and 2022 to determine the species composition in the area and the damage caused during fruit maturation. Adult individuals in flowers, leaves, and fruit surfaces were collected and identified, and silvering damage to the fruit surface was assessed in the Lleida area. Fifteen species in Lleida and 10 species in Girona were collected from the tree canopy. Organic orchards in Lleida showed lower populations and silvering damage levels when compared with integrated orchards. Thrips fuscipennis Haliday (Thysanoptera: Thripidae) 1836 was the main species in Lleida during harvest, and Frankliniella occidentalis (Pergande) 1895 was the main species in Girona. Due to their predominance, both species were associated with silvering damage during fruit maturation.

Multivariate Analysis and Optimization Scheme of the Relationship between Leaf Nutrients and Fruit Quality in ‘Bingtang’ Sweet Orange Orchards

Citrus trees require a balanced and adequate supply of macronutrient and micronutrient elements for high yield and fruit quality. Foliar nutrient analysis has been widely used in fruit-tree nutrient diagnosis and fertilization calculation. However, there is no information on ways to produce optimal fruit quality in sweet oranges. In the present study, fruit and leaf samples were collected from 120 ‘Bingtang’ sweet orange [Citrus sinensis (L.) Osbeck] orchards during four consecutive years (2019–2022). Parameters of leaf nutrition and fruit quality were analyzed based on these samples. Diagnostic results based on leaf classification standards indicated that the most deficient elements were Ca, Mg, and B, followed by N and Zn. Fruit quality, determined by single fruit weight (SFW), fruit shape index (FSI), total soluble solids (TSS), titratable acidity (TA), vitamin C (Vc), and maturation index (MI = TSS/TA) during fruit maturation, exhibited inconsistent responses to leaf mineral nutrition concentrations. The leaf-nutrient optimum values for high quality of the ‘Bingtang’ sweet orange fruit were ranges of 2.41–4.92% N, 0.10–0.28% P, 1.30–2.11% K, 2.99% Ca, 0.26–0.41% Mg, 340–640 mg/kg S, 89.65–127.46 mg/kg Fe, 13.48–51.93 mg/kg Mn, 2.60–13.84 mg/kg Cu, 15.59–51.48 mg/kg Zn, and 53.95 mg/kg for B. These results suggest the leaf-nutrient optimum values for diagnosis can be used not only to identify the nutrient constraints but also to provide guidance for the establishment of fertilization regimes in citrus cultivation.

Unraveling the Genetic Control of Pigment Accumulation in Physalis Fruits.

Physalis pubescens and Physalis alkekengi, members of the Physalis genus, are valued for their delicious and medicinal fruits as well as their different ripened fruit colors-golden for P. pubescens and scarlet for P. alkekengi. This study aimed to elucidate the pigment composition and genetic mechanisms during fruit maturation in these species. Fruit samples were collected at four development stages, analyzed using spectrophotometry and high-performance liquid chromatography (HPLC), and complemented with transcriptome sequencing to assess gene expression related to pigment biosynthesis. β-carotene was identified as the dominant pigment in P. pubescens, contrasting with P. alkekengi, which contained both lycopene and β-carotene. The carotenoid biosynthesis pathway was central to fruit pigmentation in both species. Key genes pf02G043370 and pf06G178980 in P. pubescens, and TRINITY_DN20150_c1_g3, TRINITY_DN10183_c0_g1, and TRINITY_DN23805_c0_g3 in P. alkekengi were associated with carotenoid production. Notably, the MYB-related and bHLH transcription factors (TFs) regulated zeta-carotene isomerase and β-hydroxylase activities in P. pubescens with the MYB-related TF showing dual regulatory roles. In P. alkekengi, six TF families-bHLH, HSF, WRKY, M-type MADS, AP2, and NAC-were implicated in controlling carotenoid synthesis enzymes. Our findings highlight the intricate regulatory network governing pigmentation and provide insights into Physalis germplasm's genetic improvement and conservation.

Mutation of tomato xyloglucan transglucosylase/hydrolase5 increases fruit firmness and contributes to prolonged shelf life

Fruit ripening in tomato is a highly coordinated developmental process accompanied with fruit softening, which is closely associated with cell wall degradation and remodeling. Xyloglucan endotransglucosylase/hydrolases (XTHs) are known to play an essential role in cell wall xyloglucan metabolism. Tomato XTH5 exhibits xyloglucan endotransglucosylase (XET) activity in vitro, but the understanding of its biological role in fruit ripening remains unclear. In this study, we revealed that SlXTH5 is highly expressed in mature fruits. Knockout mutant plants of SlXTH5 were generated by CRISPR/Cas9 gene editing strategy in tomato cultivar Micro-Tom. The mutant fruits showed accelerated transition from unripe to ripe process and earlier ethylene accumulation compared to wild type fruits. Although the mutation of SlXTH5 did not affect the size, weight and number of fruits, it indeed increased fruit firmness and extended shelf life, which is probably attributed to the increased cell layer and cell wall thickness of pericarp tissue. Pathogen infection experiment showed the enhanced resistance of mutant fruits to Botrytis cinerea. These results revealed the role of SlXTH5 in fruit ripening process, and provide new insight into how cell wall metabolism and remodeling regulate fruit softening and shelf life.

Characterization, Antioxidant Capacity, and Anti-Inflammatory Activity of Polyphenol-Enriched Extracts Obtained from Unripe, Mature, and Overripe Fruits of Red-Fleshed Kiwifruit Cultivars.

Discarded unripe kiwifruits (DUKs) are regarded as the major agro-byproducts in the production of kiwifruits, which have abundantly valuable secondary metabolites. Nevertheless, owing to the limited knowledge about the differences in phytochemicals and bioactivity between DUKs and mature kiwifruits, the utilization of DUKs in the food industry remains scarce. Hence, to promote their food applications, the phenolic compounds and bioactivity of discarded unripe, mature, and overripe fruits from three red-fleshed kiwifruit cultivars were studied and compared. The results revealed that the levels of total phenolics, total flavonoids, and total procyanidins in kiwifruits varied significantly by maturity stage. In addition, our findings demonstrated that DUKs possessed much higher contents of valuable phenolic compounds (e.g., chlorogenic acid (CHA), neochlorogenic acid (NCHA), gallic acid (GA), protocatechuic acid (PA), procyanidin B1 (ProcB1), procyanidin B2 (ProcB2), procyanidin C1 (ProcC1), quercetin 3-O-glucoside (QueG), and quercetin 3-O-rhamnoside (QueR)) than mature and overripe kiwifruits. Furthermore, DUKs exerted much stronger in vitro antioxidant capacity, inhibitory effects on α-glucosidase, and anti-inflammatory activity than mature and overripe kiwifruits, which were mainly attributed to their higher contents of total polyphenols and individual phenolic components, such as GA, CHA, NCHA, PA, ProcB1, ProcB2, ProcC1, and QueR. Overall, these findings provide sufficient evidence for the development and utilization of DUKs in the food/functional food industry.

Widely Untargeted Metabolomics Profiling Combined with Transcriptome Analysis Provides New Insight into Amino Acid Biosynthesis at Different Developmental Stages of Rubus Chingii Hu (Chinese Raspberry).

The composition and profile of amino acids in Rubus chingii (R. chingii) Hu serve as critical indicators of its nutritional quality. A comprehensive understanding of the amino acid metabolism within R. chingii is instrumental in the formulation and innovation of functional foods derived from this species. Utilizing advanced techniques such as wide-ranging untargeted metabolomics, transcriptome analysis, interaction network mapping, heat map analysis, and quantitative real-time PCR, we conducted a comprehensive assessment of the quality attributes across four distinct developmental stages of R. chingii. Our meticulous analysis uncovered a rich tapestry of 76 distinct amino acids and their derivatives within the developmental stages of R. chingii. The spectrum of essential amino acids was not only broad but also displayed a high degree of variety. Notably, leucine, lysine, and phenylalanine stood out as the most abundant amino acids, underscoring their significant presence throughout the growth cycle of R. chingii. The proportion of essential amino acids relative to the total amino acid content in R. chingii exhibited a notable trajectory of change throughout its developmental stages. It began with 30.92% in the immature green phase, advanced to 31.04% during the transition from green to yellow, peaked at 33.62% in the yellow to red stage, and then moderated to 30.43% in the full red phase. This pattern suggests a strategic modulation of amino acid composition, aligning with the evolving nutritional requirements and metabolic shifts as the fruit matures. Concurrent analysis of interaction networks and heat maps, alongside comprehensive profiling of amino acid metabolism and transcriptomic examination, was conducted to elucidate the intricate dynamics of cellular processes. The results showed that seven differentially expressed genes (DEGs) played important roles in amino acid metabolism, including PFK, BCAT1, TSB, ASA, ACO, TOM2AH3, and BCAT2. The expression patterns of seven DEGs conformed closely to the findings revealed by the preceding RNA-seq analysis. In this investigation, we elucidated the regulatory mechanisms underlying amino acid metabolism across the four distinct developmental stages of R. chingii through comprehensive amino acid profiling and transcriptomic analysis. These insights lay the groundwork for the development of novel functional food applications utilizing R. chingii.

Effect of fruit ripeness on electrical impedance spectrum parameters

This study aimed to reveal the mechanisms underlying changes in the electrical parameters of fruit during ripening. Plums and blueberries were selected as research objects, and their electrical parameters, firmness, water state, and microstructure with different maturities were measured. The observed relationships between fruit ripeness and electrical parameters were as follows: as fruit ripeness increased, the cell structure loosened, the number of gaps increased, membrane permeability increased, the distribution of free water became more scattered, and firmness gradually decreased. These factors led to increased cell fluid fluidity, shorter current flow paths, and lower impedance values. This study reveals the changes in various physiological indicators and electrical parameters of fruits during ripening and provides theoretical support for detecting fruit maturity using electrical parameters. These results are significant for the detection and grading of fruit maturity, extending the fruit preservation period, and developing rational fruit storage strategies.