Fruit Size Research Articles

Interactions between an arbuscular mycorrhizal inoculum and the root-associated microbiome in shaping the response of Capsicum annuum “Locale di Senise” to different irrigation levels

Abstract Background and aims The use of root-associated microorganisms emerge as a sustainable tool to enhance crop tolerance and productivity under climate change, particularly in drought-affected areas. Here, the impact of an inoculum based on arbuscular mycorrhizal fungi (AMF) was evaluated on pepper (Capsicum annuum L.) cultivation at varying water irrigation treatments (well-watered, reduced irrigation and rain-fed) under open-field conditions. Methods Agronomic and ecophysiological parameters, as well as biochemical analyses on stress markers and phytohormones in leaves and on fruit quality traits, were evaluated, along with the shifts in soil- and root-associated microbial communities. Results Rain-fed water treatment caused reduced fruit sizes, while no differences were detected among well-watered and reduced irrigation. Reduced irrigation did not cause a reduction in stomatal conductance. The highest AM fungal colonization rates were observed under reduced irrigation, and the enhanced flavonoid content and reduced oxidative stress markers in AMF-inoculated plants suggested a synergistic effect of AM fungal inoculation in boosting plant tolerance against stress. A shift in microbial community composition in the different irrigation treatments, associated with different enzymatic activity, highlighted the potential role of microbial dynamics in plant stress response under water-limited conditions. Conclusion The study suggests that a reduced irrigation comes along with beneficial impacts on pepper root associated microbes, while not impairing crop performance and yields, indicating a potential of saving water. All together, our results imply that optimization of irrigation and beneficial plant–microbe interactions, such as AM fungal symbiosis, can improve pepper physiological and productivity features under climate change.

Effects of Promalin on Fruit Growth and Cuticle Properties of ‘Pinova’ Apple

Promalin (Valent BioSciences, Libertyville, IL, USA) is a proprietary mixture of gibberellin A4 + 7 and 6-benzyladenine that is widely used in apple production to improve the fruit shape, size, and skin quality. Promalin typically increases fruit size and length. However, the increased growth likely increases the strain in the fruit skin, which may exacerbate microcracking of the cuticle and, consequently, russeting. This study aimed to monitor the growth-stimulating effect of Promalin in three different regions of fruits and investigate whether Promalin affects cuticular microcracking via effects on the deposition of cuticular components or via the accumulation of strain in the cuticle. Four Promalin sprays (20 mg⋅L−1) were applied to runoff; the first was applied at full bloom, and the remaining sprays were applied at approximately weekly intervals thereafter. Fruit surface areas and fruit surface area growth rates of the Promalin-treated fruits were higher than those of the untreated control fruits. Promalin increased the fruit length, but it had no effect on the fruit equatorial diameter. In Promalin-treated fruits, the base of each sepal extended, thickened, and became fleshy as early as 15 days after full bloom (DAFB). Allometric growth analyses revealed higher constant differential growth ratios of the pedicel and calyx length (before 36 DAFB) in Promalin-treated fruits than in control fruits. After 36 DAFB, the difference in constant differential growth ratios between Promalin-treated fruits and control fruits decreased. Cuticle mass per unit area increased with time in all regions of the fruit surface and was slightly (+3.3%) but significantly higher in fruits treated with Promalin than in control fruits. Additionally, the biaxial strain release was slightly and significantly lower in Promalin-treated fruits than in control fruits. When the isolated, cuticle was ablated from the inner surface and dewaxed, strain relaxation in the control fruits was higher than that in the Promalin-treated fruits. It was concluded that Promalin treatment increases the length of the fruit by increasing the lengths of the pedicel and calyx regions early during fruit development. Promalin only slightly increased cuticle deposition and fixation of cuticular strain. Promalin had no effects on microcracking or russeting.

Identification of QTLs involved in destemming and fruit quality for mechanical harvesting of New Mexico pod-type green chile.

Domestic production of pepper (Capsicum spp.) is shrinking while demand within the US is growing. Lack of availability and cost of labor often present an obstacle for domestic producers both practically and economically. As a result, switching to harvesting peppers mechanically is anticipated as a key strategy to help domestic producers compete in the international market. Mechanical harvest efficiency can be improved through breeding. One important trait that mechanical harvest compatible material should have is an easy destemming trait: low force separation of the pedicel and calyx from the fruit. To detect the genetic sources underlying a novel easy destemming trait for the purpose of future breeding efforts in New Mexico pod-type green chile, we performed QTL analysis on three F2:F3 populations, coming from three New Mexico pod-type varieties: 'NuMex Odyssey,' 'NuMex Iliad,' and 'NuMex Joe E. Parker,' each crossed with a parent with an easy destemming trait: MUC14. Genotyping was done through genotyping by sequencing (GBS) and phenotyping was done for destemming and fruit trait measurements. Correlations between measurements were found through the R package hmisc and QTL analysis was done through R/qtl. A strong relationship was seen between destemming and aspects of fruit morphology, particularly, destemming force and fruit width (Pearson's correlation coefficient r=0.75). Major QTLs for destemming and fruit size were discovered. Of these, the largest destemming force QTLs for all populations (PVE=34.5-69.9%) were on chromosome 10, and in two populations QTLs for destemming force were found on chromosome 3 (Percent Variance Explained (PVE)=10.7-18.8%). Fruit size-related QTLs in all populations colocalized in these same areas on chromosomes 3 and 10. This suggests that fruit shape may be genetically linked to destemming, and breeders interested in selecting for easy destemming pepper will also have to pay attention to fruit size and shape.

Transcriptome Profiles Reveal That Phytohormone Signal Transduction-related Genes Involved in Regulating Xenia in Rabbiteye Blueberry

Blueberries are small perennial evergreen or deciduous shrub berries of the genus Vaccinium in Ericaceae family. Pollination with different parental genotypes has significant effects on fruit size, fruit harvest time, fruit firmness, and chemical composition, such as soluble solids, titratable acids, anthocyanins, fructose, sucrose, glucose, flavonoids, and total phenols, showing an evident xenia effect. To understand the molecular mechanism and biosynthetic pathways involved in the xenia effect in rabbiteye blueberry, we employed transcriptome profiling by RNA sequencing to identify differentially expressed genes (DEGs) during fruit development of the variety ‘Premier’ produced by self and cross-pollination with ‘Brightwell’ and ‘Powderblue’. On the basis of the transcriptomic sequences, DEGs related to plant hormone signal transduction were identified through bioinformatics analysis, screening of DEGs, and functional enrichment analysis. The results showed that the single fruit weight and the contents of anthocyanins fructose, glucose, and sucrose showed significant differences between self- and cross-pollinated fruits, demonstrating a distinct xenia effect. High-throughput sequencing was conducted on the transcriptomes of young fruits harvested at six developmental stages (at 10-day intervals from 40 to 90 days after self- and cross-pollination). After screening and identification, 16.37 million to 25.52 million raw reads were generated and 4,937,201,302 to 7,709,896,920 clean bases were obtained. The comparison group of 80-day-old fruits generated through self-pollinated ‘Premier’ and those crossed with ‘Brightwell’ (PBR-80 vs. PPR-80) showed the largest number of DEGs (6377), of which 3052 were upregulated and 3325 were downregulated. Through further screening, 174 DEGs were found related to plant hormone signal transduction, comprising 147 known genes and 27 new genes and that 76 genes were downregulated and 98 genes were upregulated. Of the eight DEGs randomly selected for quantitative real-time polymerase chain reaction verification, their expression patterns were consistent with those revealed by high-throughput sequencing. The results elucidated the underlying mechanism of xenia, thereby providing a solid theoretical foundation for the targeted breeding, quality control, and improvement of economic benefits of blueberry, which are of important theoretical value and practical significance.

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.

Inter-annual and genotypic variation of morphological and physicochemical characters in moroccan loquat (Eriobotrya Japonica Lindil.) genotypes during two consecutive years.

Plant development is constantly affected by biotic and abiotic factors, which influence their morphology and chemical composition. In this context, the evaluation of morphological and physicochemical variation of 35 loquat genotypes during two consecutive years, 2015 and 2016, were carried out. The results revealed a significant difference of the morphological and the physicochemical traits between the two years. Indeed, 2016 showed high values for fruit and leaf traits as well as the physicochemical parmeters, while 2015 recoreded the highest values for seeds traits. In addition, the ANOVA results showed a significant effect of genotype on the physicochemical parameters and the morphological characters, excluding the geometric diameter and spherical index of seeds. Regarding the effect of year, it was also significant on physicochemical parameters and morphological traits except the size and shape of fruit and the seed shape. For the genotype x year interaction effect, it was significant on all traits studied, with the exception of the traits relating to geometric diameter of fruit and seed plus the sphericity index of the seed. Thus, size and shape of fruit remained stable over these two consecutive years. The identification of stable traits presents a result that could be beneficial for breeding programs.

Cytological and Transcriptome Analyses Provide Insights into Persimmon Fruit Size Formation (Diospyros kaki Thunb.).

Persimmon (Diospyros kaki Thunb.) fruit size variation is abundant. Studying the size of the persimmon fruit is helpful in improving its economic value. At present, the regulatory mechanism of persimmon fruit size formation is still unclear. In this study, the mechanism of fruit size formation was investigated through morphological, cytological and transcriptomic analyses, as well as exogenous ethrel and aminoethoxyinylglycine (AVG: ethylene inhibitor) experiments using the large fruit and small fruit of 'Yaoxianwuhua'. The results showed that stages 3-4 (June 11-June 25) are the crucial morphological period for differentiation of large fruit and small fruit in persimmon. At this crucial morphological period, the cell number in large fruit was significantly more than that in small fruit, indicating that the difference in cell number is the main reason for the differentiation of persimmon fruit size. The difference in cell number was caused by cell division. CNR1, ANT, LAC17 and EB1C, associated with cell division, may be involved in regulating persimmon fruit size. Exogenous ethrel resulted in a decrease in fruit weight, and AVG treatment had the opposite effect. In addition, LAC17 and ERF114 were upregulated after ethrel treatment. These results indicated that high ethylene levels can reduce persimmon fruit size, possibly by inhibiting cell division. This study provides valuable information for understanding the regulation mechanism of persimmon fruit size and lays a foundation for subsequent breeding and artificial regulation of fruit size.

Modelación de crecimiento de frutos de tangor murcott e incidencia de factores medioambientales sobre los parámetros estimados

Fruit production forecasts are a tool to plan the harvest and improve market strategies. To carry it out, it is essential to have information about the behavior of fruit development over time. The objective of this work was to find the mathematical-statistical model that best describes the growth pattern of tangor murcott fruit (Citrus reticulata x C. sinensis 'Murcott') and analyze how it is affected by environmental conditions. For this, in nine orchards, located in four locations in the province of Corrientes, Argentina, the equatorial diameter of 2,053 fruit from 82 days after full flowering to harvest were periodically registered during five seasons. The nonlinear models were compared: Logistic, Gompertz, Brody, Von Bertalanffy, Weibull, Morgan Mercer Flodin (MMF), Richards, and their respective re-parameterizations. The magnitudes of nonlinearity measures, coefficient of determination and estimates of residual deviation were considered as the main goodness-of-fit criteria. The selected model-parameterization combination was the fifth parameterization of the Logistic model with random effects on its three parameters. An Analysis of Variance model on the estimates of these parameters for each fruit showed that orchard and season factors were an important source of variability, mainly in those related to the initial size of the fruit and their growth rate. These results will allow the construction of growth tables, which in addition to making yield predictions, can be used to estimate fruit size distribution at harvest and improve the cultural practice of manual fruit thinning.

IMPROVING THE GROWTH AND PRODUCTIVITY OF FIG TREES BY SPRAYING WITH MORINGA LEAVES EXTRACTS AND GARLIC CLOVES

This experiment was conducted in a private orchard at Aldaraman, Kirkuk Governorate on "Khalobaziani" local fig trees. This study aimed to investigate the effect of spraying with Moringa leaf extract (MLE) at (0, 2, and 4 ml.l-1) and Garlic cloves extract (GCE) at (0, 10, and 20 ml.l-1) on growth and productivity of fig trees. Results showed that trees sprayed with MLE 4 ml.l-1 led to a significant increase in the leaf area, total chlorophyll content, average leaf dry weight, minerals (NPK) content in leaves, average fruit weight and size, and average yield per tree, while significantly decreased fruit cracking percentage compared to control. Furthermore, significant increase in the leaf area, total chlorophyll content, average leaf dry weight, minerals (NPK) content in leaves, and average fruit weight and size in the trees sprayed with GCE 20 ml.l-1 compared to control. The interaction between MLE 4 ml.l-1 and GCE 20 ml.l-1 showed a significant increase in the leaf area, total chlorophyll content, average leaf dry weight, and minerals (NPK) content in leaves, also significantly decreased fruit cracking percentage compared to most of the other treatments.

Herbivore and pollinator body size effects on strawberry fruit quality.

Land use change affects both pollinator and herbivore populations with consequences for crop production. Recent evidence also shows that land use change affects insect traits, with intraspecific body size of pollinators changing across landscape gradients. However, the consequences on crop production of trait changes in different plant interactors have not been well-studied. We hypothesized that changes in body size of key species can be enough to affect crop productivity, and therefore looked at how the field-realistic variation in body size of both an important pollinator, Bombus impatiens (Cresson), and a key pest herbivore, Lygus lineolaris (Palisot), can affect fruit size and damage in strawberry. First, we determined if pests vary in body size along land use gradients as prior studies have documented for pollinators; and second, we tested under controlled conditions how the individual and combined changes in size of an important pollinator and a key herbivore pest affect strawberry fruit production. The key herbivore pest was smaller in landscapes with more natural and semi-natural habitat, confirming that herbivore functional traits can vary along a land use gradient. Additionally, herbivore size, and not pollinator size, marginally affected fruit production-with plants exposed to larger pests producing smaller fruits. Our findings suggest that land use changes at the landscape level affect crop production not just through changes in the species diversity of insect communities that interact with the plant, but also through changes in body size traits.

Involvement of the tomato BBX16 and BBX17 microProteins in reproductive development

BBXs are B-Box zinc finger proteins that can act as transcription factors and regulators of protein complexes. Several BBX proteins play important roles in plant development. Two Arabidopsis thaliana microProteins belonging to the BBX family, named miP1a and miP1b, homotypically interact with and modulate the activity of other BBX proteins, including CONSTANS, which transcriptionally activates the florigen, FLOWERING LOCUS T. Arabidopsis plants overexpressing miP1a and miP1b showed delayed flowering. In tomato, the closest homologs of miP1a and miP1b are the microProteins SlBBX16 and SlBBX17. This study was aimed at investigating whether the constitutive expression of SlBBX16/17 in Arabidopsis and tomato impacted reproductive development. The heterologous expression of the two tomato microProteins in Arabidopsis caused a delay in the flowering transition; however, the effect was weaker than that observed when the native miP1a/b were overexpressed. In tomato, overexpression of SlBBX17 prolonged the flowering period; this effect was accompanied by downregulation of the flowering inhibitors Self Pruning (SP) and SP5G. SlBBX16 and SlBBX17 can hetero-oligomerize with TCMP-2, a cystine-knot peptide involved in flowering pattern regulation and early fruit development in tomato. The increased expression of both microProteins also caused alterations in tomato fruit development: we observed in the case of SlBBX17 a decrease in the number and size of ripe fruits as compared to WT plants, while for SlBBX16, a delay in fruit production up to the breaker stage. These effects were associated with changes in the expression of GA-responsive genes.

Identification and Comprehensive Analysis of OFP Genes for Fruit Shape Influence in Mango.

OVATE family proteins (OFPs) are a class of plant-specific proteins with a conserved OVATE domain that play fundamental roles in fruit development and plant growth. Mango (Mangifera indica L.) is an economically important subtropical fruit tree characterized by a diverse array of fruit shapes and sizes. Despite extensive research on OFPs across various species, there remains a scarcity of information regarding OFPs in mango. Here, we have successfully identified 25 OFP genes (MiOFPs) in mango, each of which exhibits the conserved OVATE domains. The MiOFP gene exhibit a range of 2-6 motifs, with all genes containing both motif 1 and motif 2. Phylogenetic analysis on 97 OFPs (including 18 AtOFPs, 24 SlOFPs, 25 MiOFPs, and 30 OsOFPs) indicated that MiOFPs could be divided into three main clades: clade I, II, and III. Comparative morphological analysis identified significant variations in fruit longitudinal diameter, fruit transverse diameter, and fruit shape index between two distinct shaped mango cultivars ('Hongxiangya' and 'Jingpingmang') at DAP5, DAP7, and DAP10 stages. The subsequent examination of paraffin sections revealed distinct patterns of cell elongation. The majority of MiOFP genes exhibited predominantly expressed in developing organs, specifically flowers and immature fruits, while displaying distinct expression patterns. RNA-Seq analysis revealed significant disparities in the expression levels of several OFP genes, including MiOFP5, MiOFP11, MiOFP21, MiOFP22, MiOFP23, and MiOFP25, between the two mango cultivars. These findings suggest that these six genes may play a crucial role for fruit shape in mango, especially the MiOFP22. The findings of this study have established a basis for future investigations into MiOFPs in mango, offering a solid foundation for further research in this field.

Comparative analysis of colchicine and bio-catharanthine as mutagenic agents for polyploid generation in wild passion fruit (Passiflora foetida)

Wild type Passiflora foetida or a bush passion fruit is unappealing plant with small fruit size (2-3 cm) to be cultivated as a fruit crop. Plant breeding by polyploidization may improve plant production including increase the fruit size. Many researchers have used colchicine as plant chromosome-modifying agent for polyploidization. However, this potent mutagen is very expensive in developing countries and toxic. Hence, an alternative mutagen needs to be considered, such as the natural bio-catharanthine. This study aims to evaluate the effectiveness of colchicine and bio-catharanthine mutagens in polyploidization of P. foetida plants. Experiment was arranged in split-plot design with three replications. Main plot was combination of the mutagens and concentrations, the subplot was soaking durations. Twenty-five seeds each were soaked for 1-, 2- and 3-days in distilled water as control, colchicine (0.05%, 0.1%, 0.15%) and bio-catharanthine (0.5%, 1% and 1.5%) solutions. Result showed, bio-catharanthine concentration of 1% at immersion durations of 3-days and 1.5% at 1-, 2- and 3-days could only produce 89, 56, 74, and 71% grade 1 mixoploid plants accordingly. On the other hand, colchicine succeeded in obtaining tetraploid plants at concentration of 0.15% with 3-days soaking time even though at lower result (5%). Lower colchicine concentrations with shorter or the same soaking period could only produce 5% grade 2 mixoploid plants. Colchicine with one-tenth lower concentration than bio-catharanthine concentration is still more efficient in inducing polyploidy. Further research by involving bio-catharanthine concentration and varying the soaking time must be pursued to obtain higher-level ploidy.

Effect of forchlorfenuron (CPPU) on fruits quality and residue analysis in kiwifruits

N-(2-Chloro-4-pyridyl)-N′-phenylurea (CPPU) is a plant growth regulator that promotes cell division and cell expansion in fruits. The present investigation was performed to observe the impact of CPPU on kiwifruit, specifically focusing on quantitative attributes, such as fruit size and shape, as well as the nutritional and residual levels of the fruit after CPPU application. This experiment was conducted on three kiwifruit varieties: Xuxiang, Jintao, and Zhonghua 50. The research entailed immersing the fruits in different concentrations of CPPU at 20 days after flowering. These findings demonstrate that CPPU has a positive impact on increasing fruit size and improving quality, while also preserving the ideal flavone, sugar-acid ratios and high levels of vitamin C. In addition, CPPU treatment enhanced the phenolic content of the fruit. Although high quantities of CPPU had a detrimental influence, the residues of CPPU in 'Xuxiang', 'Jintao', and 'Zhonghua 50' kiwifruits were 0.001, 0.002, and 0.002 mg/kg, respectively, at a dosage of 10 mg/kg. At a concentration of 20 mg/kg, the residues were 0.004, 0.003, and 0.003 mg/kg. No residues were detected at a concentration of 5 mg/kg. All residue levels were in accordance with China's national food safety regulations (MRL <0.05). Hence, this study proposes that a concentration of 10 mg/L CPPU shows potential for fruit cultivation, as it achieves a harmonious combination of improved fruit characteristics and adherence to food safety standards.

Biochemical characterization of mulberry (Morus spp.) genotypes from the Türkiye (Hizan, Bitlis): A comprehensive analysis of fruit properties and bioactive compounds

AbstractThe present study was carried out to assess the fruit traits and phytochemical properties of 39 mulberry genotypes [Morus alba L. (16 white mulberry), Morus rubra L. (11 red mulberry), and Morus nigra L. (12 black mulberry)] selected in Bitlis province (Hizan) of Türkiye. Approximately, 1 kg fruit were hand‐harvested from each genotype. The fruit size, fruit color, pH, titratable acidity, soluble solids content (SSC), vitamin C, total phenolics, total flavonoids, antioxidant activity, and individual phenolic compounds were determined. The fruit weight varied between 1.80 and 5.84 g in black mulberry, 1.22 and 4.18 g in red mulberry, and 1.29 and 3.10 g in white mulberry. In white mulberry, SSC was determined to be between 19.00% and 38.86%, and in black and red mulberry it was between 11.86% and 21.90% and 12.60% and 18.90%, respectively. The titratable acidity rate, which varied depending on the species, was lower in white mulberry, but the highest acidity rate was recorded in red mulberry. Vitamin C was determined as 33.13 mg 100 g−1 in red mulberry, 24.10 mg 100 g−1 in black mulberry, and 14.03 mg 100 g−1 in white mulberry. Total phenolics in mulberries varied depending on the species, and the red mulberry fruit contained higher phenolic substances, followed by black and white mulberries. The total flavonoids varied between 0.27 and 7.83 g QE kg−1, whereas the flavonoids varied depending on the species and genotype. The highest values in terms of bioactive compounds were recorded in fruits of the 13HZN23 and 37 genotypes. Black and red mulberry fruit were found to have higher levels of individual phenolic content than the white mulberrry fruit.

Comprehensive Evaluation of Apple Germplasm Genetic Diversity on the Basis of 26 Phenotypic Traits

We used 256 apple germplasm resources for a thorough examination of the genetic diversity associated with 26 phenotypic traits (i.e., genetic diversity analysis, cluster analysis, correlation analysis, principal component analysis, and membership function). The average coefficient of variation for 12 morphological traits was 66.39% (21.10–201.5%). The coefficient of variation was highest and lowest for the fruit arris and the width of the eye basin, respectively. Additionally, the diversity index ranged from 0.54 to 1.33. Moreover, the coefficient of variation for 14 numerical traits varied from 5.37% to 50%. The titratable acid content had the highest coefficient of variation, with a diversity index ranging from 2.01 to 2.08 (average of 2.045). A cluster analysis categorized 256 germplasms into four groups, among which Group I included germplasms with large fruits and the best comprehensive performance. Of the top 10 principal components revealed by the principal component analysis, principal component 1 was mainly related to fruit size and flavor. The top 10 germplasms were selected on the basis of comprehensive scores using the membership function method. Furthermore, a stepwise regression analysis identified 15 key traits for identifying apple germplasms, including the vegetative growth day, fruit weight, and the firmness of the fruit without skin. These results can serve as the foundation for future analyses of the phenotypic diversity of apple germplasms, while also providing a theoretical basis for screening, characterizing, and further improving excellent apple germplasms.

Bioprocess of Gibberellic Acid by Fusarium fujikuroi: The Challenge of Regulation, Raw Materials, and Product Yields.

Gibberellic acid (GA3) is a tetracyclic diterpenoid carboxylic acid synthesized by the secondary metabolism of Fusarium fujikuroi. This phytohormone is widely studied due to the advantages it offers as a plant growth regulator, such as growth stimulation, senescence delay, flowering induction, increased fruit size, and defense against abiotic or biotic stress, which improve the quality and yield of crops. Therefore, GA3 has been considered as an innovative strategy to improve agricultural production. However, the yields obtained at large scale are insufficient for the current market demand. This low productivity is attributed to the lack of adequate parameters to optimize the fermentation process, as well as the complexity of its regulation. Therefore, this article describes the latest advances for potentializing the GA3 production process, including an analysis of its origins from crops, the benefits of its application, the related biosynthetic metabolism, the maximum yields achieved from production processes, and their association with genetic engineering techniques for GA3 producers. This work provides a new perspective on the critical points of the production process, in order to overcome the limits surrounding this modern line of bioengineering.

Fruits and seed characteristics of chihua squash (Cucurbita argyrosperma Huber.) accessions from Yucatan, Mexico

Objective: To evaluate some fruit and seed characteristics of six chihua squash genotypes obtained in the Yucatan Peninsula. Materials and methods: Six collections of Cucurbita argyrosperma Huber, obtained in the Yucatan Peninsula, were evaluated in a randomized complete block design for two years. The number of fruits per plot, fruit weight and size, seed weight and number of total, empty and full-filled seeds per fruit were quantified, and degrees Brix of the pulp. Results: Differences in fruit production were found between collections. The dominant fruit size was medium, fruits between 500 and 999 g, with the Chetumal collection standing out, while the variables of seed weight and number of seeds were affected between collections and between years, because of low rainfall during the production cycle of the second year. All collections recorded a reduction in weight and an increase in the number of empty seeds. Slight variations were identified in the concentration of degrees Brix of the pulp, with the Chetumal collection standing out above the rest. Conclusions: The evaluated collections present variability within them, which can be useful to select materials for different purposes and to obtain more benefits from this crop

Overexpression of Solanum lycopersicum DDB1 interacting protein 4 (SlDDI4) extends tomato shelf life by methylation-mediated suppression of softening-related genes expression

Prolonging the fruit storage period is strategically important due to the limitation of postharvest life determined by excessive softening. Efforts have been made to alleviate the issue of fruit softening in transgenic fruit by suppressing genes that encode cell wall-degrading proteins. However, individual genes related to the degradation of cell walls have limited ability, resulting in minimal success. SET domain-containing protein (SET protein) is widely expressed in most plant organs and crucial in plant growth and development. A tomato SET protein was previously identified as SlDDI4 (Solanum lycopersicum DDB1 interacting protein 4) with a H3K9 methyltransferase activity involving cell proliferation and organ size regulation. In this study, we demonstrated that SlDDI4 overexpression (SlDDI4-OE) promotes fruit firmness in addition to increased fruit size. Further experimental investigations revealed that the increased expression of SlDDI4 inhibited cellulase and pectinase activities, consequently increasing the proportion of cellulose and insoluble pectin. RNA-seq profiling indicated the genes involved in cell wall metabolism in SlDDI4-OE fruit were significantly down-regulated. DNA methylation and McrBC-PCR analysis at the SlCEL2, SlPG2, and SlEXP12 loci revealed that their down-regulation was associated with the elevated methylation level in the individual promoter regions. Furthermore, up-regulation of SlDDI4 generated fruit with increased lycopene content and prolonging shelf-life by approximately 20 d without adverse impacts on the flavor indicators. Thus, our results suggest that manipulation of SlDDI4 expression enables broad favorable effects on postharvest life as well as fruit size and quality through chromatin remodeling.

Impact of polyploidization on genome evolution and phenotypic diversity in oil-tea Camellia

Oil-tea Camellia (OTC) is a valuable oil crop with diverse applications across the food, cosmetics, and medicine sectors. However, understanding the impact of chromosome polyploidization on genome evolution and phenotypic diversity in OTC remains challenging. This study addressed this knowledge gap by focusing on the origins and impacts of OTC polyploidization. The chromosomal karyotypes of 10 representative samples were examined, and their relationships were elucidated through hierarchical clustering analysis of karyotype parameters. Based on the phylogeny of the genus Camellia, the ancestral 1 C-value and 1 Cx-value were reconstructed, revealing an increase in the 1 C-value and a reduction in the 1 Cx-value associated with polyploidization. Notable positive correlations between ploidy level, genome size, and fruit size were highlighted by phylogenetic generalized least squares analysis. The phenotypic characteristics and chromosomal evolution of OTC were reconstructed. It was inferred that the genus Camellia, which was originally diploid, underwent 11 chromosomal duplication events. With the emergence of polyploidization, phenotypic traits transitioned from small fruits, autumn–winter flowering, and white flowers to larger fruits, spring flowering, and red flowers. Biogeographically, it is suggested that OTC first appeared in the Lingnan region, and subsequent species dispersion and hybridization significantly influenced the emergence of polyploid species. In conclusion, evidence has shown that OTC polyploidization increases genome size and enhances phenotypic diversity. This research enhances our understanding of the complex genetic mechanisms that drive species evolution, influence genome changes, and contribute to the domestication of Camellia plants. Furthermore, these findings offer insights that can inform future breeding and cultivation strategies for OTC.