Stages Of Fruit Development Research Articles

Unraveling Calcium Absorption and Distribution in Peach and Nectarine during Fruit Development through 44Ca Isotope Labeling.

Calcium foliar applications are known to effectively enhance peach quality; however, the optimal implementation strategy regarding fruit developmental stages and cultivars remains unclear. In this study, three different moments of fruit Ca applications in peach and nectarine are tested: Early season, Mid-season, and Late season. For this aim, the 44Ca isotope was used as a tracer, enabling the quantification and location of the Ca derived from the foliar fertilizer. Stone, flesh, and skin 44Ca enrichment was separately analyzed at harvest. The results indicate that Ca absorption in the fruits from external CaCl2 applications was influenced by the timing of the application during fruit development, with Late-season applications proving to be the most effective in increasing the Ca content in the fruit, corresponding with a higher fruit size at the application moment. Nevertheless, no differences in the absorption efficiency were found between the three timings of the application. Furthermore, the Ca from the foliar fertilizer in the fruit predominately remained in the flesh, followed by the skin. The Ca derived from the foliar fertilizer reached the stone in all of the experimental situations, but the Early- and Mid-season applications resulted in the highest amount of Ca derived from the fertilizer in this part of the fruit. Interestingly, the peach exhibited a higher Ca absorption efficiency compared to the nectarine, likely due to the presence of trichomes that retain the foliar fertilizer on the fruit surface. In conclusion, the Ca absorption and distribution in peaches depends on the cultivar and timing of the Ca application.

Double-Heading Produces Larger Fruit via Inhibiting EjFWLs Expression and Promoting Cell Division at the Early Stage of Loquat Fruit Development

Loquat is an evergreen fruit crop which blooms from autumn–winter, and supports human beings with juicy fruit from late spring to early summer. However, the most traditional cultivars of this crop produce small fruit and bear a much lower yield than its relatives like apple, pear and peach. Large-size cultivars have long been a cherished aim of breeders for improving the production yield of loquat. Agronomic practices like panicle thinning, fruit thinning, growth regulator application, fertilization and so on are easier and more accessible ways for growers to produce large-size loquat fruit on existing production trees. Here, we develop a novel pruning method with an annual double back-cut, which provides vigorous shoot with more leaves and thicker branches for bearing much larger loquat fruit. Cellular observation determined that the vigorous shoot training method motivated cell division to produce larger loquat fruit, and that most of these cell layers were proliferated before the appearance of flower blossoms. Gene expression data of four development stages showed that EjFWL1 and EjFWL2 were notably downregulated in flower buds of the vigorously pruned tree. The data here further confirmed that the cell division capacity during flower development greatly influenced both the flower and fruit size of loquat. More importantly, we developed a novel pruning method to inhibit cell division repressors, promote cell proliferation and enlarge fruit size in loquat.

Genome-Wide Identification and Characterization of Sucrose Metabolism Genes Involved in Actinidia rufa and Their Expression Profiling during the Fruit Developmental Stages

Soluble sugars, as an indispensable source of energy, play crucial roles in plant growth and development. However, to date, scant information about the sucrose metabolism-related gene families is available in kiwifruit (Actinidia rufa Planch). Here, we systematically identified the members of various gene families encoding crucial enzymes or transporters involved in sucrose metabolism, re-analyzed their expression patterns under different fruit development stages, and determined the regulatory mechanism involving key transcription factors. A total of sixty-two genes from six gene families (thirty-one ArINVs, two ArSPPs, four ArSPSs, nine ArSUSs, six ArSUCs/SUTs, and ten ArSWEETs) were identified in the A. rufa genome. The characterization of these members, including gene structure, motifs, conserved domains, and cis-acting elements, were analyzed. Phylogenetic analysis revealed that these gene families could be categorized into six distinct subgroups. These six gene families have undergone strong purifying selection during domestication. In addition, expression analysis of the 62 genes indicated that differential expression patterns are highly regulated by developmental processes. Specifically, we identified 11 transcription factors that were rigorously correlated (r > 0.98) with key gene expression profiles. This represents a comprehensive analysis of the genes involved in sucrose metabolism in kiwifruit, which provides useful information for further functional analysis of these genes.

ERF transcription factors govern anthocyanin biosynthesis in litchi pericarp by modulating the expression of anthocyanin biosynthesis genes

Anthocyanins are the most prevalent phytochemicals that color the fruits. Ethylene promotes fruit ripening and modulates anthocyanin biosynthesis in plants, however, the underlying molecular mechanism in litchi is unclear. Herein, the slow-reddening cultivar ‘Feizixiao’ (FXZ) and swift-reddening cultivar ‘Guiwei’ (GW) were selected to study the regulation of anthocyanin biosynthesis in litchi. Total anthocyanin contents were found to be higher in ‘GW’ and lower in ‘FZX’. We then comprehensively investigated ethylene response factor (ERF) subfamily genes and their expression patterns in different tissues and fruit developmental stages. Using transcriptome data, eight LcERF genes were identified as putative key genes associated with litchi pericarp coloration and anthocyanin accumulation. To test whether these genes are expressed under ethephon treatment, we applied 100 and 200 µL L−1 ethephon 4 weeks before harvest. Ethephon treatment dramatically increased anthocyanin accumulation as well as the expression of targeted ERF genes. LcERF1/22/25/37 were significantly upregulated in response to ethephon treatment, while LcERF64 was significantly downregulated. Anthocyanin content and expression of anthocyanin-related genes were considerably reduced in LcERF1/22/25/37-silenced fruits, but the opposite trend was observed in LcERF64-silenced fruits. Yeast-one-hybrid and dual luciferase assays revealed that the tested ERFs bind to the promoters of key anthocyanin biosynthesis genes and alter their expression. These findings suggested that ethylene promotes anthocyanin accumulation and consequently fruit coloration by stimulating the positive anthocyanin biosynthesis regulators LcERF1/22/25/37, or by suppressing the negative regulator LcERF64, which regulates the expression LcDFR and LcMYB1 by directly binding to their promoters.

Comparative transcriptomic study of matured fruit and post-fruit developmental stages in Malaysian durian varieties

Durian (Durio zibethinus Murr.) is a famous tropical fruit in Malaysia and well-known for its sweet and creamy taste and unique strong aroma. Despite the differences, durian fruit undergo similar fruit developmental stages upon maturity. However, not much information related to metabolic changes at molecular level are available for fruit development in durian. Hence, the aim of this study was to identify and analyze fruit development transcriptomic changes on six commercial durian varieties (D24, D99, D160, D168, D197, and D200). The transcriptome analysis via RNA-seq assays generated 67 to 234 million raw reads, which are assembled into 49,601 genes with protein coding genes as the largest gene biotype, with a total of 35,832 genes (72.2%). All genes were annotated against Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). GO analysis revealed genes were highly linked to biological process, cellular components and molecular function, with the highest representation in cell wall, while the most common pathways identified by KEGG were carotenoid biosynthesis, fatty acid biosynthesis, starch and sucrose metabolism, phenylpropanoid biosynthesis and galactose metabolism. Important changes were found in abscisic acid and lignin accumulation, which associated with post-harvest response and concurrent colour change. Moreover, significant increase in butyric acid, palmitoyl-CoA and different forms of sugars were associated with buttery smell, creamy texture, and sweetness respectively. Thus, mass sequence data and expression profiling provide an insight into molecular mechanisms for durian fruit developmental process. This study aims to enhance comprehension of durian fruit development stages, including physiological, genetic, and molecular processes, to inform breeding, crop enhancement, and post-harvest strategies to meet consumer and agro-biotechnology demands.

Characterization of the GGP gene family in potato (Solanum tuberosum L.) and Pepper (Capsicum annuum L.) and its expression analysis under hormonal and abiotic stresses

GDP-l-galactose phosphorylase (GGP) is a key rate-limiting enzyme in plant ascorbic acid synthesis, which plays an important role in plant growth and development as well as stress response. However, the presence of GGP and its function in potato and pepper are not known. In this study, we first identified two GGP genes in each potato and pepper genomes using a genome-wide search approach. We then analyzed their physicochemical properties, conserved domains, protein structures and phylogenetic relationships. Phylogenetic tree analysis revealed that members of the potato and pepper GGP gene families are related to eggplant (Solanum melongena L.), Arabidopsis (Arabidopsis thaliana L.), tobacco (Nicotiana tabacum L.) and tomato (Solanum lycopersicum L.), with tomato being the most closely related. The promoter sequences mainly contain homeopathic elements such as light-responsive, hormone-responsive and stress-responsive, with light-responsive elements being the most abundant. By analyzing the structure of the genes, it was found that there is no transmembrane structure or signal peptide in the GGP gene family of potatoes and peppers, and that all of its members are hydrophilic proteins. The expression profiles of different tissues show that StGGP1 has the highest expression levels in leaves, StGGP2 has the highest expression levels in stamens, and CaGGPs have the highest expression levels in the early stages of fruit development (Dev1). It was found that StGGPs and CaGGPs genes showed different response to phytohormones and abiotic stresses. Abscisic acid (ABA) treatment induced the most significant change in the expression of StGGPs, while the expression of CaGGPs showed the most pronounced change under methyl jasmonate (MeJA) treatment. StGGPs responded mainly to dark treatment, whereas CaGGPs responded mainly to NaCl stress. These results provide an important basis for a detailed study about the functions of GGP homologous genes in potato and pepper in response to abiotic stresses.

Integrated multi-omics analysis provides molecular insights into flavor variation in melons grafted onto two different pumpkin rootstocks during fruit development

Melon fruit flavor is a key quality characteristic that influences consumer preference. Grafting is an effective technique to enhance fruit quality but yields divergent outcomes in terms of fruit flavor. To address this problem, we analyzed parallel changes in flavor-related metabolite accumulation and gene expression in two pumpkin rootstock grafted melons during four fruit developmental stages. We identified 26 061 expressed genes and 840 metabolites from 21 different compound classes, including carbohydrates, amino acids, and lipids. We also detected 50 aroma volatile compounds in the grafted melons. Results showed that genes and metabolites associated with metabolic pathways (carbohydrate, amino acid, lipid, and phenylpropanoid) play a key role in flavor formation. Compared with ‘Sizhuang 12’, ‘Tianzhen 1’ rootstock improved melon fruit flavor by upregulating sugar-related genes (HK, MPI, MIOX, and STP) and inducing metabolite accumulation (d-ribose-5-phosphate, d-galactose, and trehalose 6-phosphate), whereas decreasing bitterness-related amino acids (l-arginine, l-asparagine, and l-tyrosine) and associated genes (thrC, ACS, and GLUL) expression at ripening stage. Furthermore, ‘Tianzhen 1’ exhibited higher expression levels of enzyme-coding genes (4CL, CSE, and COMT) responsible for aroma volatile synthesis than ‘Sizhuang 12’ rootstock. Taken together, our results decipher the basis of the molecular mechanism underlying fruit flavor in grafted melons and provide valuable information for the melons genetic improvement.

Identification of MAP65 family genes in tomato and the member SlMAP65-1 is involved in fruit morphogenesis

The plant growth process is accompanied by dynamic changes in the microtubules, and the rearrangement of microtubules is regulated by diverse microtubule-associated proteins (MAPs). Plant MAP65s have been exhaustively characterized in some species, but the information about MAP65 family members in tomato (Solanum lycopersicum) is limited. In this study, nine SlMAP65 family genes were identified in the tomato genome. Then a systematic analysis including physio-chemical properties, evolution, conserved motifs, domains, gene structure, and cis-regulatory elements of SlMAP65 family members was conducted. The member SlMAP65-1, which had the highest expression, was knocked out by CRISPR/Cas9. The tomato fruit of slmap65-1 loss of function lines showed an elongated morphology, and the data indicated that SlMAP65-1 was involved in fruit morphogenesis at early fruit development stage. These results provided insights for fruit morphogenesis-related research areas and future functional studies of SlMAP65 family members in tomato.

PbbHLH137 interacts with PbGIF1 to regulate pear fruit development by promoting cell expansion to increase fruit size.

The regulation of fruit development is a complex process and a core issue in the fruit tree industry. To investigate the role of PbGIF1 in pear fruit development, we identified a transcription factor PbbHLH137 that regulates pear (Pyrus bretschneideri) fruit development by screening a yeast library constructed from fruit cDNA. Yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC), and split luciferase complementation (split-LUC) assays were performed to confirm the PbbHLH137-PbGIF1 interaction. By tracing the complete fruit development process, we found that PbbHLH137 expression was closely related to fruit size and highly involved at the late pear fruit development stage. Transgenic experiments showed that heterologous expression of PbbHLH137 or PbGIF1 promoted fruit enlargement. PbbHLH137 promoted mainly the expansion of fruit cell volume, whereas PbGIF1 mainly increased the number of cells. Further LUC experiments demonstrated that PbGIF1 promoted the transcriptional activation ability of PbbHLH137. Our work identified PbbHLH137 as a transcription factor that regulates fruit development, and showed that PbGIF1 played an ongoing role during fruit development, making it a candidate gene for genetic improvement of pear fruit development.

The gap-free genome and multi-omics analysis of Citrus reticulata 'Chachi' reveal the dynamics of fruit flavonoid biosynthesis.

Citrus reticulata 'Chachi' (CRC) has long been recognized for its nutritional benefits, health-promoting properties, and pharmacological potential. Despite its importance, the bioactive components of CRC and their biosynthetic pathways have remained largely unexplored. In this study, we introduce a gap-free genome assembly for CRC, which has a size of 312.97Mb and a contig N50 size of 32.18Mb. We identified key structural genes, transcription factors, and metabolites crucial to flavonoid biosynthesis through genomic, transcriptomic, and metabolomic analyses. Our analyses reveal that 409 flavonoid metabolites, accounting for 83.30% of the total identified, are highly concentrated in the early stage of fruit development. This concentration decreases as the fruit develops, with a notable decline in compounds such as hesperetin, naringin, and most polymethoxyflavones observed in later fruit development stages. Additionally, we have examined the expression of 21 structural genes within the flavonoid biosynthetic pathway, and found a significant reduction in the expression levels of key genes including 4CL, CHS, CHI, FLS, F3H, and 4'OMT during fruit development, aligning with the trend of flavonoid metabolite accumulation. In conclusion, this study offers deep insights into the genomic evolution, biosynthesis processes, and the nutritional and medicinal properties of CRC, which lay a solid foundation for further gene function studies and germplasm improvement in citrus.

Fruit quality, antioxidant, and mineral attributes of pomegranate cv. Ghojagh, influenced by shading and spray applications of potassium sulfate and sodium silicate

Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and ⁰hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality.

The jacktree genome and population genomics provides insights for the mechanisms of the germination obstacle and the conservation of endangered ornamental plants.

Sinojackia Hu represents the first woody genus described by Chinese botanists, with all species classified as endangered ornamental plants endemic to China. Their characteristic spindle-shaped fruits confer high ornamental value to the plants, making them favored in gardens and parks. Nevertheless, the fruits likely pose a germination obstacle, contributing to the endangered status of this lineage. Here we report the chromosome-scale genome of S. xylocarpa, and explore the mechanisms underlying its endangered status, as well as its population dynamics throughout evolution. Population genomic analysis has indicated that S. xylocarpa experienced a bottleneck effect following the recent glacial period, leading to a continuous population reduction. Examination of the pericarp composition across six stages of fruit development revealed a consistent increase in the accumulation of lignin and fiber content, responsible for the sturdiness of mature fruits' pericarps. At molecular level, enhanced gene expression in the biosynthesis of lignin, cellulose and hemicellulose was detected in pericarps. Therefore, we conclude that the highly lignified and fibrotic pericarps of S. xylocarpa, which inhibit its seed germination, should be its threatening mechanism, thus proposing corresponding strategies for improved conservation and restoration. This study serves as a seminal contribution to conservation biology, offering valuable insights for the study of other endangered ornamental plants.

A New Plant-Wearable Sap Flow Sensor Reveals the Dynamic Water Distribution during Watermelon Fruit Development

This study utilized a plant-wearable sap flow sensor developed by a multidisciplinary team at Zhejiang University to monitor water distribution patterns in watermelon fruit stalks throughout their developmental stages. The dynamic rules of sap flow at different stages of fruit development were discovered: (1) In the first stage, sap flow into the fruit gradually halts after sunrise due to increased leaf transpiration, followed by a rapid increase post-noon until the next morning, correlating with fruit expansion. (2) In the second stage, the time of inflow sap from noon to night is significantly shortened, while the outflow sap from fruit is observed with the enhancement of leaf transpiration after sunrise, which is consistent with the slow fruit growth at this stage. (3) In the third stage, the sap flow maintains the diurnal pattern. However, the sap flow that inputs the fruit at night is basically equal to the sap flow that outputs the fruit during the day; the fruit phenotype does not change anymore. In addition, a strong correlation between the daily mass growth in fruit and the daily sap flow amount in fruit stalk was identified, validating the sensor’s utility for fruit growth monitoring and yield prediction.

Genome-wide analysis of AP2/ERF transcription factors that regulate fruit development of Chinese prickly ash

BackgroundAP2/ERF is a large family of plant transcription factor proteins that play essential roles in signal transduction, plant growth and development, and responses to various stresses. The AP2/ERF family has been identified and verified by functional analysis in various plants, but so far there has been no comprehensive study of these factors in Chinese prickly ash. Phylogenetic, motif, and functional analyses combined with transcriptome analysis of Chinese prickly ash fruits at different developmental stages (30, 60, and 90 days after anthesis) were conducted in this study.ResultsThe analysis identified 146 ZbAP2/ERF genes that could be classified into 15 subgroups. The motif analysis revealed the presence of different motifs or elements in each group that may explain the functional differences between the groups. ZbERF13.2, ZbRAP2-12, and ZbERF2.1 showed high levels of expression in the early stages of fruit development. ZbRAP2-4, and ZbERF3.1 were significantly expressed at the fruit coloring stage (R2 and G2). ZbERF16 were significantly expressed at fruit ripening and expression level increased as the fruit continued to develop. Relative gene expression levels of 6 representative ZbAP2/ERFs assessed by RT-qPCR agreed with transcriptome analysis results.ConclusionsThese genes identified by screening can be used as candidate genes that affect fruit development. The results of the analysis can help guide future genetic improvement of Chinese prickly ash and enrich our understanding of AP2/ERF transcription factors and their regulatory functions in plants.

Identification and variation of specific volatile compounds during fruit development and postharvest stage in Japanese apricot (Prunus mume Sieb. et Zucc.) fruit

AbstractFruit aroma of Japanese apricot is distinct, and the specific volatile compounds are not clearly known during fruit development and during post‐harvest stage. This study therefore aimed to explore the volatile compounds present during these stages. The volatile compounds were analysed by headspace solid‐phase microextraction and gas chromatography–mass spectrometry. OAV, PCA and electronic nose techniques were used to determine the characteristic aroma components. Enzyme‐linked immunoassay (ELISA) was also applied to determine the activity of enzymes. The results showed that in the cultivars ‘Xiyeqing’ a total of 52 components that included 20 terpenes, 15 aldehydes, 9 esters, 3 ketones and 5 other substances were detected during fruit development and post‐harvest stage. While in the cultivar ‘Xiaoyezhugan’ a total of 49 components that included 25 terpenes, 7 aldehydes, 11 esters, 1 alcohol, 3 ketones and 2 other substances were also detected during fruit development and post‐harvest stage. We concluded that the characteristic volatile compounds of mature Japanese apricot fruit were (+)‐limonene, linalool, damascenone, β‐damascenone and nonanal, finding the basis for the fruity, floral and sweet aroma of the Japanese apricot fruit. Further analysis indicated that low temperature inhibited the synthesis of esters and terpenes, and dark conditions were more favourable to the synthesis of volatile compounds than light conditions. Short‐term storage of Japanese apricot fruit at room temperature and dark conditions was conducive for the maintenance of volatile compounds, and low‐temperature storage was the most destructive to the fruit volatile compounds. These findings form a theoretical foundation for exploring the specific volatile compound of Japanese apricot and helped to determine the optimal storage condition of post‐harvest stage for Japanese apricot fruit.

Identification and expression profiling of SmGATA genes family involved in response to light and phytohormones in eggplant.

GATA proteins are transcription factors of zinc finger proteins, which play an important role in plant growth development and abiotic stress. However, there have been no identification or systematic studies of the GATA gene family in eggplant. In this study, 28 SmGATA genes were identified in the genome database of eggplant, which could be divided into four subgroups. Plant development, hormones, and stress-related cis-acting elements were identified in promoter regions of the SmGATA gene family. RT-qPCR indicated that 4 SmGATA genes displayed upregulated expressions during fruit developmental stage, whereas 2 SmGATA genes were down-regulated expression patterns. It was also demonstrated that SmGATA genes may be involved in light signals to regulate fruit anthocyanin biosynthesis. Furthermore, the expression patterns of SmGATA genes under ABA, GA and MeJA treatments showed that the SmGATAs were involved in the process of fruit ripening. Notably, SmGATA4 and SmGATA23 were highly correlated with the expression of anthocyanin biosynthesis genes, light-responsive genes, and genes that function in multiple hormone signaling pathways and the proteins they encoded were localized in the nucleus. All these results showed GATA genes likely play a major role in regulating fruit anthocyanin biosynthesis by integrating the light, ABA, GA and MeJA signaling pathways and provided references for further research on fruit quality in eggplant.

Influence of growth stages on the nutritional value of Momordica balsamina leaf powder

The nutritive mineral element concentrations of most African leafy vegetables (ALVs) are influenced by the plant’s growth stages. Momordica balsamina is an ALV in the Cucurbitaceae family, rich with nutraceutical and pharmaceutical properties, available in the plant at different growth stages. A greenhouse study was conducted to determine the responses of the nutritional value of M. balsamina leafy vegetable harvested at different growth stages. Six growth stages, namely, vegetative (reference), bud development, flower initiation, fruit set, fruit development and physiological maturity, served as treatments, with 10 replicates and arranged in RCBD. Treatments had highly significant (P ≤ 0.01) effect on the tested nutritional quality, namely, potassium (K), calcium (Ca), magnesium (Mg), zinc (Zn), iron (Fe) and phosphorus (P). Relative to the reference, K was the highest (1206 mg/L) at flower initiation stage, whereas the highest Ca (127.70 mg/L) and Zn (2.21 mg/L) concentrations occurred at the fruit development stage. At the physiological maturity stage, the highest Mg (25.19 mg/L), P (16.54 mg/L) and Fe (5.49 mg/L) concentrations, were recorded. Noticeably, during early growth stages, P, Fe and Zn were negatively reduced, when compared to K, Ca and Mg, which were increasing at every growth stages. In conclusion, the greatest accumulation of the tested mineral elements was mainly observed as from when the leafy vegetable started setting fruit until physiological maturity stage.

Impact of Fruit Load on the Replenishment Dynamics of Internal Water Reserves in Olive Trees

Stem refilling has been studied in many forest species, but its impact on olive trees remains underexplored. This study aims to examine the effect of varying fruit loads on stem refilling rates in olive trees. The experiment was conducted in a commercial olive orchard over two years, characterized by a biennial bearing cycle with minimal fruit production in 2021 (“OFF” year) and maximal fruit production in 2022 (“ON” year). Sap flow sensors measured the water volume differences traversing the apex and base of main branches in two experimental trees. Tree water status was monitored using psychrometers, and soil moisture content was continuously recorded. Results suggest that alternate bearing significantly affects the stem refilling process, while soil moisture availability also plays a pivotal role. During the “ON” year, water reserve consumption increased to 63.6% compared to the “OFF” year to meet the water requirements of developing fruits. Replenishment occurred at various times throughout the 24 h period, including early morning, afternoon, and night when stomatal conductance measurements indicated stomatal closure. During the “ON” year, olive trees experienced intense nocturnal replenishment of reserves, regardless of soil moisture, water vapor pressure deficit, or fruit development stage. These findings offer novel insights into olive trees’ rehydration dynamics that can be used to optimize irrigation scheduling and improve water use efficiency.

Postharvest disease, latent infection, and preharvest control of ‘Shine-Muscat’ grapes

The cultivation of ‘Shine-Muscat’ grape variety is rapidly expanding in East Asia due to its exceptional qualities favored by consumers. However, studies on the disease pathogens affecting this variety and how to control them remain limited. This study focuses on investigating postharvest diseases that impact ‘Shine-Muscat’ grapes and explores potential prevention methods, with regional emphasis on Shanghai metropolitan area, a key market for edible grapes in China. Common market diseases such as Alternaria spot, grey mold, and Aspergillus rot are frequently found in ‘Shine-Muscat’ grapes, accounting for 29.2%, 20.4%, and 16.7% of diagnostic cases, respectively. The study revealed that Alternaria spp., Cladosporium spp., and Botrytis cinerea could attach to or invade grape fruits during the flowering, young fruit, and veraison stages of ‘Shine-Muscat’. In contrast to conventional open field cultivation methods, the rain-shelter and root restriction cultivation can aid in reducing fruit disease incidence during production, and thus alleviate the postharvest disease risks. Moreover, the application of calcium propionate during fruit development stages could efficiently manage both in-field and post-harvest diseases, and extend storage life of harvested fruit.

Comparative analysis of POD genes and their expression under multiple hormones in Pyrus bretschenedri

BackgroundClass III peroxidase (POD) enzymes play vital roles in plant development, hormone signaling, and stress responses. Despite extensive research on POD families in various plant species, the knowledge regarding the POD family in Chinese pear (Pyrus bretschenedri) is notably limited.ResultsWe systematically characterized 113 POD family genes, designated as PbPOD1 to PbPOD113 based on their chromosomal locations. Phylogenetic analysis categorized these genes into seven distinct subfamilies (I to VII). The segmental duplication events were identified as a prevalent mechanism driving the expansion of the POD gene family. Microsynteny analysis, involving comparisons with Pyrus bretschenedri, Fragaria vesca, Prunus avium, Prunus mume and Prunus persica, highlighted the conservation of duplicated POD regions and their persistence through purifying selection during the evolutionary process. The expression patterns of PbPOD genes were performed across various plant organs and diverse fruit development stages using transcriptomic data. Furthermore, we identified stress-related cis-acting elements within the promoters of PbPOD genes, underscoring their involvement in hormonal and environmental stress responses. Notably, qRT-PCR analyses revealed distinctive expression patterns of PbPOD genes in response to melatonin (MEL), salicylic acid (SA), abscisic acid (ABA), and methyl jasmonate (MeJA), reflecting their responsiveness to abiotic stress and their role in fruit growth and development.ConclusionsIn this study, we investigated the potential functions and evolutionary dynamics of PbPOD genes in Pyrus bretschenedri, positioning them as promising candidates for further research and valuable indicators for enhancing fruit quality through molecular breeding strategies.