Stages Of Fruit Development Research Articles

Regulatory mechanism of carbohydrate metabolism pathways on oil biosynthesis of oil plant Symplocos paniculata

The mechanism underlying oil synthesis in oil plant fruits remains elusive, as sugar metabolism provides the essential carbon skeleton without a clear understanding of its intricate workings. The transcriptome and oil and sugar metabolites’ content of Symplocos paniculate, an extraordinary oil plant with immense ecological significance, were subjected to a comparative analysis throughout fruit development. The findings unveiled that the impact of sugar metabolism on oil synthesis varied throughout distinct stages of fruit development. Remarkably, during the initial phase of fruit development from 10 to 90 days after flowering (DAF), pivotal genes involved in starch biosynthesis, such as ADP-glucose pyrophosphorylase (AGP), starch synthase (SS), and starch branching enzyme (SBE), facilitated an earlier accumulation of starch within the fruit. Whereas, during the fruit maturation stage (from 90 DAF to 170 DAF), the expression of phosphofructokinase 1 (PFK-1), pyruvate kinase (PK) and pyruvate dehydrogenase (PDH) enzyme genes involved in the glycolysis pathway was significantly upregulated, thereby facilitating a rapid and substantial accumulation of oil. The sugar metabolism activity of S. paniculata fruit exerts a crucial influence on the process of oil synthesis, which is highly dependent on the specific developmental stage. These significant discoveries provide potential candidate genes for advanced genetic improvement using molecular biotechnology, thus enhancing both fruit oil production and modifying the composition of fatty acids.

Transcriptomic and Phenotypic Responses of CucumberTrichome Density to Silver Nitrate and Sodium Thiosulfate Application

Cucumber (Cucumis sativus L.) is one of the most widely cultivated crops worldwide and is valued for its nutritional, economic, and ecological benefits. The regulation of defense mechanisms against herbivores, along with osmotic loss and environmental regulation, is greatly affected by trichomes in cucumbers. In this study, we attempted to characterize trichomes and examined fruit physiological and transcriptome profiles by RNA sequencing in cucumber breeding lines 6101-4 and 5634-1 at three stages of fruit development through foliar application with a combination of silver nitrate (AgNO3) and sodium thiosulfate (Na2S2O3) in comparison to non-treated controls. Notable increases in the number of trichomes and altered forms were observed for both inbred cultivars 6101-4 and 5634-1 against foliar application of chemical substances. RNA-seq analysis was performed to identify differentially expressed genes (DEGs) involved in multiple pathways in cucumber trichome formation. The enrichment of differentially expressed transcripts showed that foliar application upregulated the expression of many stress-responsive and trichome-associated genes including plant hormone signal transduction, sesquiterpenoid and triterpenoid biosynthesis, and the mitogen-activated protein kinase (MAPK) signaling pathway. The dominant regulatory genes, such as allene oxide synthase (AOS) and MYB1R1 transcription factor, exhibited significant modulations in their expression in response to chemical application. The RNA-seq results were further confirmed by RT-PCR-based analysis, which revealed that after chemical application, the dominant regulatory genes, such as allene oxide synthase (AOS), PTB 19, MYB1R1, bHLH62-like, MADS-box transcription factor, and salicylic acid-binding protein 2-like, were differentially expressed, implying that these DEGs involved in multiple pathways are involved the positive regulation of the initiation and development of trichomes in C. sativus. A comparison of trichome biology and associated gene expression regulation in other plant species has shown that silver nitrate (AgNO3) and sodium thiosulfate (Na2S2O3) are also responsible for hormonal and signaling pathway regulation. This study improves our knowledge of the molecular mechanisms involved in C. sativus trichome development. It also emphasizes the possibility of utilizing chemical composition to modulate C. sativus trichome-related characteristics of C. sativus, leading to the improvement of plant defense mechanisms as well as environmental adaptation.

Fruit Cuticle Thickness and Anatomical Changes in Pedicel Xylem Vessels Influence Fruit Transpiration and Calcium Accumulation in Cranberry Fruit.

Ca is a key nutrient for fruit quality due to its role in bonding with pectin in the cell wall, providing strength through cell-to-cell adhesion, thus increasing fruit firmness and extending post-harvest life. However, Ca accumulation is mostly limited to the initial stages of fruit development due to anatomical and physiological changes that occur as fruits develop. The objective of this study was to evaluate fruit transpiration, cuticle thickness, and pedicel vessel changes during cranberry fruit development and the effect these parameters might have on Ca translocation. 'Stevens' cranberry fruits were collected weekly, starting seven days after full bloom (DAFB) until 70 DAFB. For each collection date, fruit transpiration was evaluated in the field, and samples were taken to analyze total fruit Ca content, stomata density, cuticle thickness, pedicel anatomical changes, and xylem functionality. Ca accumulation in the fruit exhibited a sigmoidal curve, beginning at 0.04 mg per berry at 7 DAFB, increasing to a maximum of 0.1 mg per berry at 28 DAFB, and remaining constant until harvest (70 DAFB). Fruit Ca accumulation was mostly explained by fruit transpiration, which exhibited a similar sigmoidal pattern. The rapid decline in fruit transpiration was largely modulated by increases in cuticle thickness, as well as anatomical changes in the pedicel xylem, thereby reducing the capacity to transport water and nutrients into the fruit. Thus, this research could help cranberry growers maximize fruit Ca content by prioritizing fertilization during the early stages of fruit development.

Application of Plant Growth Regulators During Early Fruit Development Stage Increased Perceived Sweetness of Mango Fruit

This study investigated the optimal strategies for improving sugar biosynthesis in mango fruits. Randomized block design was used for experimental treatments. The mango cultivar “Renong-1” was sprayed with five green plant growth regulators, including solutions of SBP (sucrose-based polymers, a new highly efficient and eco-friendly plant growth regulator), SPM (sucrose + potassium dihydrogen phosphate + microelement fertilizer), TPM (taurine + potassium dihydrogen phosphate + microelement fertilize), PFA (potassium fulvic acid), and SOP (seaweed oligosaccharide peptide) at different fruit development stages. Indicators, such as soluble solid content, soluble sugar and starch contents, and activities of 11 enzymes associated with sugar metabolism in physiologically mature and in full ripening fruits were evaluated. The results showed that SBP solution diluted 100-fold exerted the strongest effect on the soluble sugar content and sweetness value of “Renong-1” mango fruits. Based on the linear regression analysis, a significant negative correlation was observed between the activity of acid invertase and the perceived sweetness of physiologically mature fruits, while the activities of other enzymes were significantly negatively correlated with the perceived sweetness of full ripening fruits. According to multiple regression (by lars function in R) and other comprehensive analysis, A1B3 (spraying SBP solution one time in the young fruit stage) was selected as the optimal treatment combination for enhancing “Renong-1” mango perceived sweetness, followed by A1B2 (spraying SBP solution for the first time in the young fruit stage and the second time at medium maturity) as the alternative treatment combination.

Abscission zone metabolism impacts pre- and post-harvest fruit quality: a very attaching story

The function of abscission zones (AZs) determines the timing of fleshy fruit abscission, with important consequences not only for the optimal fruit harvest, but also on the overall final fruit quality. In this context, chemical treatments are commonly used at different stages of fruit development to control fruit abscission, which can also have positive or negative effects on fruit quality. In the current review, we examine commonly used chemicals that affect the metabolic activity in the AZs of fleshy fruit, in addition to their effects on fruit quality characteristics. The main hormone metabolism and signaling in the AZ include that of ethylene, auxin, abscisic acid and jasmonates, and the molecular components that are involved are covered and discussed, in addition to how these hormones work together to regulate AZ activity and hence, affect fruit quality. We focus on studies that have provided new insight into possible protein complexes that function in the AZ, including multiple MADS-box transcription factors, with potential overlapping regulatory roles which exist between AZ development, ethylene production, AZ activation, fruit ripening and overall fruit quality. The view of the AZ as a cross roads where multiple pathways and signals are integrated is discussed.

Comprehensive Analysis of CaFAD Genes Involved in Fatty Acid Accumulation in Coffea arabica and Functional Characterization of CaFAD8 in Transgenic Arabidopsis thaliana

The quality of Coffee arabica L. beans, particularly the aroma, is a key determinant of commercial value. Fatty acids, as precursors of volatile aroma compounds, play a crucial role in this quality. Screening and identification of their related genes are of particular significance. This study identified 21 members of the CaFAD gene family in the C. arabica genome using bioinformatics tools. Gene duplication events observed in the CaFAD gene family were likely driven by natural selection and mutation pressure, with natural selection being more prominent. Transcriptome sequencing, qRT-PCR, and fatty acid profiling across four fruit developmental stages revealed that CaFAD8 was closely associated with fatty acid synthesis regulation. Fatty acid content was initially high but decreased during the later stages, while CaFAD8 expression showed an inverse pattern. Subcellular localization indicated that CaFAD8 functions primarily on the inner membrane. CaFAD8-OE heterologous expression experiment in Arabidopsis thaliana reduced the total fatty acid content in seeds but increased unsaturated fatty acids, including oleic, linoleic, and linolenic acids. These findings suggest that CaFAD8 promotes fatty acid unsaturation and provides insights into fatty acid metabolism in C. arabica. This study offers a foundation for understanding CaFAD gene regulation and supports breeding strategies for high-oil C. arabica varieties.

The Renaissance of Polyamines: New Roles in Crop Yield and Quality Properties in Freshly Fruit

Polyamines (PAs) are low-molecular-weight compounds that contain amino groups. PAs are present in a variety of organisms, including plants, animals and microorganisms. In plants, the main PAs are putrescine (PUT), spermidine (SPD) and spermine (SPM). They play crucial physiological roles in plant development, including flowering, fruit set, growth, ripening and metabolic processes. In addition, PAs are components of the diet and have a role in health and disease. Furthermore, PAs have been demonstrated to help overcome the negative effects of adverse environmental factors of both biotic and abiotic stresses. Thus, the main objective of this review was to examine the recent literature regarding the mentioned effects of PAs apart from the impact of preharvest PAs treatments, applied at different stages of fruit development, on fresh fruit crop yield and fruit quality properties at harvest, and in their maintenance during storage, with a special emphasis on the fruit content in bioactive compounds with antioxidant activity. Moreover, this review addressed the impact of PAs on other physiological processes affecting crop yield such as flowering and fruit set.

Long-term nitrogen fertilization alters the partitioning of amino acids between citrus leaves and fruits.

The growth of evergreen fruit trees is influenced by the interaction of soil nitrogen (N) and leaf amino acid contents. However, information on free amino acid contents in leaves of fruiting and non-fruiting branches during long-term N fertilizer application remains scarce. Here, a four-year field experiment (2018-2021) in a citrus orchard revealed consistently lower total N and amino acid contents in leaves of fruiting compared to non-fruiting branches. Appropriate N fertilizer application increased free amino acid and total N contents in leaves of both types of branches and fruits, but excessive amounts led to decreases. Correlation analysis showed that, in the early stage of fruit development, leaves on both types of branches can meet the N requirements of the fruit (R²=0.77 for fruiting, R²=0.82 for non-fruiting). As fruits entered the swelling stage, a significant positive correlation emerged between fruiting branch leaves and fruit total N content (R²=0.68), while the R² for leaves on non-fruiting branches dropped to 0.47, indicating a shift in N supply towards leaves on fruiting branches. Proline and arginine are the most abundant amino acids in these leaves. At fruit maturity, these amino acids account for more than half of the total amino acids in the fruit (29.0% for proline and 22.2% for arginine), highlighting their crucial role in fruit development. Further research is needed to investigate amino acid transport and distribution mechanisms between citrus leaves and fruits.

Recent changes in thermal indices in Mango cv Dashehari under subtropical climate

Systematic recording of changes in thermal indices at tree phenological stages is prerequisite to understand the impact of environmental factors on mango. Keeping this in view, latest information on growing degree day units, heliothermal and photothermal units were cumulated at flowering, fruit set, fruit development and maturity stages in mango cv Dashehari during growing season of 2021 and 2022. Recent data showed variability in environmental indicators during critical reproductive stages. Highest weekly mean maximum temperature of 39.50 and 44.21°C were recorded in 2021 and 2022 fruiting cycles while minimum temperature showed 1.29°C during 2022 and 3.79°C in 2021. During 2022, bright sunshine hours had maximum value of 15.59h whereas in 2021, 10.7 h. During reproductive stage, weekly mean pan evaporation of 4.46 to 10.01 mm/day was recorded in 2021 fruiting cycle; in contrast, in the next season, 4.77 to 10.06 h was observed. Weekly average growing degree day from January to June varied between 860.51 to 2347.91°Cd and 917.16 to 2597.30°Cd respectively in 2021 and 2022 growth cycles. The heliothermal units had 3094.05 to 17727.54 and 3534.42 to 23219.79°Cdh with photothermal of 8932.92 to 32084.15 and 9517.23 to 35498.52 °Cdh respectively in 2021 and 2022 fruiting seasons. The flowering stages experienced lower heat accumulation in 2021 as compared to 2022 fruiting seasons. It was observed that peanut and marble phase had around 884.48 to 1606.44°Cd GDD across fruiting season. Maturity period had 1655.41 to 2597.3°Cd GDD across seasons. Histographic distribution of these thermal indices at vegetative, flowering, fruit setting to maturity had indicated widespread distribution pattern of GDD, HTU and PTU across seasons. It was found that a 1500 to 1600°Cd GDD at frequency level of <5 per cent in 2021 marble stage while the same GDD at 6 per cent frequency level with higher 1600 to 1700°Cd class intervals at <2 per cent was noted in the next season fruiting. Such widespread distribution indicated the affect of climatic factors at each stage and season. Lower fruit production of 6 to 8 t ha-1 was accorded due to severe atmospheric aberration during the 2022 cropping cycle. Results suggested the impact of environmental factors on tree performances and thus resource conservation practices needs to be followed rigorously to attain optimum yield of mango at subtropics.

Study on the physiological mechanism and transcriptional regulatory network of early fruit development in Gleditsia sinensis Lam. (Fabaceae)

BackgroundGleditsia sinensis Lam. (Fabaceae) is a medicinal legume characterized by its spines and pods, which are rich in saponins, polysaccharides, and various specialized metabolites with potential medicinal and industrial applications. The low fruit set rate in artificially cultivated economic forests significantly impedes its development and utilization. A comprehensive understanding of the cellular events, physiological and biochemical processes, and molecular regulatory mechanisms underlying fruit initiation and early fruit development is essential for enhancing yield. However, such information for G. sinensis remains largely unexplored.ResultsIn this study, we identified that the early fruit development process in G. sinensis can be categorized into three distinct stages: pollination, the critical period of fertilization, and the initial fruit development followed by subsequent growth. The dynamic changes in non-structural carbohydrates and endogenous plant hormones within the ovary were found to play a significant role during fruit set and the early stages of fruit development. Additionally, the high activity of gibberellin, cytokinin, and sucrose-metabolizing enzymes in the ovary was conducive to early fruit development. Furthermore, we generated high-resolution spatiotemporal gene expression profiles in the ovary from the stage of efflorescence to early fruit development. Comparative transcriptomics and weighted gene co-expression network analysis revealed specific genes and gene modules predominant at distinct developmental stages, thereby highlighting unique genetic programming. Overall, we identified the potential regulatory network governing fruit initiation and subsequent development, as well as the sets of candidate genes involved, based on the aforementioned results.ConclusionsThe results offer a valuable reference and resource for the application of exogenous substances, such as hormones and sugars, during critical fruit development periods, and for the development of molecular tools aimed at improving yield.

The hexose transporters CsHT3 and CsHT16 regulate postphloem transport and fruit development in cucumber.

Hexoses are essential for plant growth and fruit development. However, the precise roles of hexose/H+ symporters in postphloem sugar transport and cellular sugar homeostasis in rapidly growing fruits remain elusive. To elucidate the functions of hexose/H+ symporters in cucumber (Cucumis sativus L.) fruits, we conducted comprehensive analyses of their tissue-specific expression, localization, transport characteristics, and physiological functions. Our results demonstrate that CsHT3 (C. sativus hexose transporter), CsHT12, and CsHT16 are the primary hexose/H+ symporters expressed in cucumber fruits. CsHT3 and CsHT16 are localized in the sieve element-companion cell during the ovary and early fruit development stages. As the fruit develops and expands, the expression of both symporters shifts to phloem parenchyma cells. The CsHT16 knockout mutant produces shorter fruits with a larger circumference, likely due to impaired sugar and phytohormone homeostasis. Concurrent reduction of CsHT3, CsHT12, and CsHT16 expression leads to decreased fruit size. Conversely, CsHT3 overexpression results in increased fruit size and higher fruit sugar levels. These findings suggest that CsHT16 plays an important role in maintaining sugar homeostasis, which shapes the fruit, while CsHT3, CsHT12, and CsHT16 collectively regulate the supply of carbohydrates required for cucumber fruit enlargement.

Dynamics of Nutritional Compounds and Antioxidant Activity during Date Palm Fruit Development and Maturity Stages

Date palm fruit development involves several stages, including Habauk, Kimri, Khalal, Rutab, and Tamer stages, characterized by intricate biochemical alterations that lead to the accumulation of various metabolites. The objective of this study was to quantify and statistically evaluate the linearity of nutritional compounds, acidity levels, water content, dry matter, secondary metabolites, and antioxidant activity capacity across the fruit development and maturation stages of two date palm cultivars, Deglet Nour and Degla Beida. Fruits were collected from ten palm trees per cultivar at each growth stage, cleaned, sliced, dried, and powdered. The acidity level was assessed using the Marx method, while water content and dry matter were determined through a drying method. The carbohydrates, proteins, and fats that constitute the nutritional components were quantified using established techniques. The extraction yield of secondary metabolites was calculated using date powder. The water content, PH, carbohydrate, protein, fat content, extraction yield, total Phenol, and total flavonoid content displayed dynamic patterns described by second-order polynomials. The maximum local values for water content, PH, and carbohydrate were observed in both varieties, while the maximum local value for total Phenol was found exclusively in Deglet Nour. Conversely, the minimum local values for protein content, fat content, total flavonoid content, and extraction yield were observed in both varieties. Notably, the minimum local value for total Phenol content was observed only in Degla Beida. For both varieties, the dry matter and antioxidant activity exhibited quadratic dynamics. However, the dry matter showed a positive increasing trend, while the antioxidant activity exhibited a change in the opposite direction.

ZF-HD gene family in rapeseed (Brassica napus L.): genome-wide identification, phylogeny, evolutionary expansion and expression analyses

BackgroundThe zinc finger-homeodomain (ZF-HD) transcription factor family is widely involved in regulating plant growth and fruit filling, as well as responding to various abiotic stress. Rapeseed (Brassica napus L.), the second largest oil-producing crop in the world, is an annual or biennial herb of Brassica in Cruciferae. However, there is currently no systematic study on the evolutionary relationship and stress response of ZF-HD transcription factors in rapeseed.ResultsIn this study, 60 ZF-HD genes in B. napus (BnZHDs) were identified and named based on the chromosomal location. The evolutionary relationships, classifications, gene structures, motif compositions, chromosome localization, and gene replication events in these BnZHD genes were systematically analyzed. These 60 BnZHD members were divided into seven groups. According to the phylogenetic tree and repetitive events, subfamilies MIF, and V may have undergone stronger expansions during the evolutionary process. Interestingly, segmental duplications may have a more important contribution, which distinguishes them from other dicotyledon plants. To further investigate the evolutionary relationship of the ZF-HD family, we constructed eleven comparative genomic maps of homologous genes between rapeseed and different representative monocotyledonous and dicotyledonous plants. Finally, the gene expression pattern of 15 BnZHD genes from different subfamilies under different tissues, fruit developmental stages, and different abiotic stress were analyzed. The expression profile from real-time quantitative PCR analysis showed different expression patterns of BnZHD gene in B. napus. We found that certain BnZHD genes are preferentially expressed in specific tissues of B. napus, while most genes are expressed in multiple tissues. For example, BnZHD37, BnZHD53, and BnZHD55 may be sensitive to different hormones. Under different stresses, the expression of BnZHD3, BnZHD4, BnZHD7, BnZHD38, BnZD45, and BnZHD53 significantly increased in roots, stems, and leaves within 24 h. These genes may play important roles in the growth, development, and environmental adaptation of rapeseed.ConclusionsThese findings provide a basis for a comprehensive understanding of the ZF-HD family in rapeseed, which will provide information for further research on the functional characteristics of the BnZHD genes.

Foliar Spraying of Potassium Sulfate during Fruit Development Comprehensively Improves the Quality of Citrus Fruits

Sugar accumulation is influenced by various fertilizer treatments, of which potassium spraying is the most effective. However, the effect of different potassium sources as a foliar application at different fruit development stages on citrus fruits is still unclear. In this study, three different potassium fertilizers and one water (F1: 0.65% KNO3, F2: 0.88% KH2PO4, F3: 0.56% K2SO4, and F4: water) were sprayed on Citrus reticulata cv. Nanfeng at cell division, cell expansion, fruit ripening, and throughout fruit developmental stages, respectively. Results showed that the six-time K2SO4 application had the best function in enhancing fruit physiological attributes such as fruit weight and the total carotenoids; also, this treatment significantly decreased TA (titratable acid), increased fruit TSS (total soluble solids), soluble sugar content, and TSS:TA ratio. Furthermore, K2SO4 spraying obviously increased the expression of CsCWINV-2/6 in the segment membrane, and CsSUT-1/2 and CsVPP-1/2 in fruit juices. Taken together, six-time application of K2SO4 throughout fruit developmental stages produced better fruit quality, at least through enhancing sink strength and promoting sugar transportation in citrus fruits. This study might effectively contribute to maximizing fruit quality and its marketability.

Dynamic Transformations in Fruit Color, Bioactive Compounds, and Textural Characteristics of Purple-Fleshed Dragon Fruit (Hylocereus costaricensis) Across Fruit Developmental Stages Under Humid Tropical Climate

Purple-fleshed dragon fruit is gaining popularity worldwide due to its distinctive characteristics and health benefits. This climbing cactus, introduced to humid tropical climates, presents challenges in assessing fruit quality. The dynamic transformations in fruit color, bioactive compounds, and textural attributes across 11 developmental stages from 10 to 32 days after flowering under humid tropical conditions were studied. Color analysis revealed significant intensification of red-violet hues, with L* values decreasing by 14.74% and a* values increasing from −8.14 to 32.96. The color transformation is initiated in the pulp at 25 days and the peel at 27 days after flowering. Betalain synthesis commenced after 20 days with rapid accumulation between 25 and 32 days, correlating with color development. Antioxidant activity increased from 79.38% at 10 days to 86.76% at 20 days, followed by a steady decline. Phenolic content peaked at 121.40 mg gallic acid equivalent per 100 g at 25 days before declining, while the flavonoid content decreased with the advancement of fruit development. Concurrent reduction in peel thickness and fruit firmness was also observed. These findings show that purple-fleshed dragon fruit can adapt well to humid tropical conditions, with a 32-day developmental cycle, offering vital insights into quality and maturation phases.

The R2R3 MYB700 activates the expression of biosynthetic genes involved in the accumulation of (+)-catechin but not (-)-epicatechin in Chinese plum fruits (Prunus salicina Lindl.)

Chinese plum fruits are rich in phenolic compounds from the flavan-3-ol family, including (+)-catechin and (-)-epicatechin, widely associated with sensory attributes such as bitterness and astringency, beneficial for human health, and involved in enzymatic browning. Leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) enzymes catalyze (+)-catechin and (-)-epicatechin biosynthesis, respectively. It has been described that genes encoding for LAR and ANR are transcriptionally regulated by transcription factors belonging to MYB, bHLH, and bZIP families. In this study, we examined two Chinese plum cultivars (‘98–99’ and ‘Angeleno’) with different flavan-3-ol profiles to characterize MYB transcription factors involved in malus the accumulation of (+)-catechin and (-)-epicatechin in fruits. We observed that fruits of ‘98–99’ accumulate a higher content of (+)-catechin than (-)-epicatechin, while ‘Angeleno’ displays an opposite profile. We identified PsaMYBPA1, PsaMYB7, and a MYB transcription factor not previously described in the literature, which we named PsaMYB700. The expression of PsaMYB700 was up to 10-fold higher in ‘98–99’ than ‘Angeleno’ at the earliest fruit developmental stage. Promoter activation assays indicated that PsaMYBPA1 activates the flavan-3-ol-related genes LAR, anthocyanidin synthase (ANS), and ANR, while PsaMYB7 and PsaMYB700 activate LAR and ANS. In contrast to PsaMYBPA1 and PsaMYB7, PsaMYB700 displays high activation levels without the presence of a bHLH co-regulator. Further, the expression levels of PsaMY700 positively correlate with the higher (+)-catechin accumulation in fruits of ‘98–99,’ compared with ‘Angeleno.’ Finally, we detected a PsabZIP5 with similar expression levels between cultivars, which activates the promoters of PsaMYBPA1, PsaMYB7, and PsaMYB700. This study elucidates the roles of PsaMYBPA1, PsaMYB7, PsaMYB700 and PsabZIP5 in flavan-3-ol biosynthesis, highlighting a hierarchy of transcriptional regulation of these compounds.

Genome-wide survey and expression analysis of JAZ genes in watermelon (Citrullus lanatus).

BACKGROUND JAZ: (Jasmonate ZIM-domain) genes play important roles in plant growth and JA signaling pathway which is correlated with fruit ripening process. However, there have been few reports on the genome-wide identification of JAZ genes in watermelon and its relationship with fruit ripening. METHODS AND RESULTS: In this study, bioinformatics approaches were employed to identify ClaJAZ genes of watermelon at the genome-wide levels. Further exploration delved into the phylogenetic relationships, chromosomal mappings, promoter dynamics, expression, and architectural features of the JAZ genes. The results showed that a total of 9 ClaJAZ genes unevenly distributed across six chromosomes were identified in the watermelon genome, and they all have conserved Jas and TIFY domains. These JAZ genes were divided into four distinct groups with five genes involved in inter-chromosomal tandem duplication events, and members of the same subgroup exhibited a high degree of similarity in their gene structure and protein motif patterns. Analysis of the promoter regions of the ClaJAZ genes indicated the presence of cis-acting elements associated with hormonal responses, stress, and developmental processes. Gene expression analysis through real-time quantitative PCR (qRT-PCR) showed that there were spatiotemporal differences in the expression of ClaJAZ genes at various stages of fruit development. Among them, ClaJAZ7 has the highest level of transcriptional expression and showed strong promoter activity. CONCLUSIONS: This study conducted a comprehensive analysis of the ClaJAZ genes and provided insights into the role of ClaJAZ in the development and ripening of watermelon fruit.

Genome-wide identification, structural characterization and expression profiling of AP2/ERF gene family in bayberry (Myrica rubra)

BackgroundBayberry is the most economically significant fruit within the Myricaceae family, having high nutritional and medicinal value. The AP2/ERF family is a class of transcription factors found mainly in plants. However, the bayberry AP2/ERF gene family has not previously been studied.ResultsIn this study, 113 members of the bayberry AP2/ERF gene family were identified. According to the phylogenetic tree, the members of this group are divided into three subfamilies, namely AP2, ERF, and DREB. The gene structure and conserved motifs were analyzed. Chromosome localization showed that 95 genes were unevenly distributed on 8 chromosomes and 18 genes were located on the skeleton. Gene collinearity analysis of the bayberry AP2/ERF gene family showed 12 segmental duplication events, involving 21 AP2/ERFs. In addition, we further investigated the evolutionary relationship of the AP2/ERF gene family between bayberry and six other species. It was found that bayberry was most closely related to Populus trichocarpa and Malus pumila, with 153 and 141 homologous gene pairs, respectively. Cis-acting elements indicated that AP2/ERFs were related to phytohormone responses, light response, abiotic and biotic stress tolerance. Transcriptomic data showed that the expression pattern of AP2/ERF gene was different in bayberry space electric field treatment and at different stages of fruit development. The results of GO annotation revealed the biological processes, cellular component and molecular function that the AP2/ERF genes were involved. And KEGG enrichment analysis indicated that these genes were mainly clustered in genetic information processing and metabolism pathways.ConclusionsThe AP2/ERF gene was identified in the genome of bayberry, and its structure, conserved motif, and phylogenetic relationship were analyzed. These findings of this study serve as a reference for the genome-wide identification of the AP2/ERF gene family in other species and groundwork for future research on the function of AP2/ERF genes in bayberry.

Impact of crown architecture on light availability, gas exchange, flowering and fruiting in jamun (Syzygium cumini [L.] Skeels)

Experiments were conducted to assess the impact of crown architecture on light availability beneath the trees, flowering, fruiting, yield and quality of jamun (Syzygium cumini [L.] Skeels). Trees were maintained as control, palmette and open centre crown. Impact was evaluated for three consecutive years, i.e. 2017–2019. Diffuse light beneath the trees ranged from 69.7 ± 2.22 to 45.9 ± 1.45%, whereas direct light varied from 30.4 ± 0.97 to 54.1 ± 1.78%. At flowering and fruit development stage (June), photosynthesis rate (A) in control trees was 12.5 ± 0.43 μmol CO2/m2/s; however, at fruit maturity and dormancy (August), it was only 9.5 ± 0.35 μmol CO2/m2/s. Similarly, in palmette and open centre trees, photosynthesis rate at flowering and fruit development stage was 13.5 ± 0.46 and 15.7 ± 0.54 μmol CO2/m2/s, respectively; whereas at fruit maturity and dormancy, photosynthesis rate dropped to 10.5 ± 0.39 and 11.7 ± 0.43 μmol CO2/m2/s, respectively. Substantial variation in stomatal conductance (gs), vapour pressure deficit (VPD) and transpiration rate (E) was also found. Days to start flowering ranged from 92 ± 0.33 to 98 ± 0.33. Similarly, days to end flowering varied from 99 ± 0.07 to 107 ± 0.36, days to fruit set 132 ± 0.33 to 139 ± 0.33 and days to fruit maturity 176 ± 0.48 to 184 ± 0.63. Significant variation in fruit length, fruit width and fruit weight was also found. Total soluble solids in fruit pulp varied from 9.0 ± 0.15 to 12.2 ± 0.149°Brix and fruit yield 62.3 ± 1.5 to 86.7 ± 1.33 kg per tree. Noteworthy variation in fruit quality traits was also recorded. This study illustrates that crown architecture has considerable impact on gas exchange parameters, flowering, fruiting, yield and quality of jamun.

PpMYB10.1 regulates peach fruit starch degradation by activating PpBAM2.

Starch degradation, a crucial source for soluble sugar, significantly influences fruit flavor development during ripening. Key enzymes in this process include α-amylases (AMYs) and β-amylases (BAMs). In this study, we identified 5 PpAMYs and 9 PpBAMs in peach and categorized them into three and four groups, respectively, based on the gene structures and the phylogenetic analysis. Subsequent expression analysis revealed thatelevated levels of PpAMY1, PpAMY5, and PpBAM2 were detected in the middle and late stages of fruit development, suggesting their positive involvement in starch degradation during peach fruit ripening. Transient overexpression experiments conducted in peach fruits and callus further demonstrated that overexpression of PpBAM2 significantly reduced starch content, indicating its important role in starch degradation during peach fruit ripening. Furthermore, we identified a R2R3-MYB transcription factor, PpMYB10.1, which activated the expression of PpBAM2 through the direct interacting with its promoter. In addition, transient overexpression of PpMYB10.1 could significantly reduce starch content in peach callus. Consequently, our findings highlight the positive role of PpBAM2 in peach starch degradation, with PpMYB10.1 serving as an activator during this process.