Fruit Size Research Articles

The pomological characteristics and values for public health of Crataegus tanacetifolia

This study aimed to determine the pomological characteristics and allometric relationships of Crataegus tanacetifolia, an endemic plant species in Türkiye, as well as to assess its significance for public health. Fruit samples collected from its natural habitat were subjected (Mihalıççık district of Eskişehir province, 1330-1350m) to pomological measurements. Subsequently, pomological characteristics were correlated with allometric relationships. The following pomological parameters were observed for Crataegus tanacetifolia: fruit length was 15.30±1.70mm, width was 19.51±2.30mm, thickness was 18.85±2.30mm, weight was 3.34±0.99g, flesh weight was 2.73±0.901g, arithmetic mean diameter was 17.89±2.04mm, geometric mean diameter was 17.78±2.02mm, sphericity index was 116.26±4.79%, surface area was 1005.55±223.28mm2, appearance ratio was 0.79±0.05, seed ratio was 0.19±0.04, peduncle length was 3.26±0.24mm, flesh hardness was 14.02±1.61kg/cm2, and fruit color (L*a*b) was 71.54±0.92*9.34±1.82*60.62±3.11. The fruit color ranged from light yellow to light pink, with green being the dominant color in unripe fruits. The seed length was 7.20±0.51 mm, width was 4.14±0.37mm, thickness was 5.42±0.43mm, weight was 0.12±0.02g, volume was 53.73±8.48mm3, and surface area was 80.09±9.29. There was a high relationship between fruit surface area and allometric relationships, with R²=0.9603 and R²=0.8729 confidence interval. The allometric relationships between seed ratio and fruit sizes were in the range of R²=0.3984 and R²=0.5045. In this study, it was determined that Crataegus tanacetifolia is important for public health, its fruits are used as food.

Resurrecting plant–animal interactions in the Caribbean can benefit large‐fruited plants

Many plants benefit from seed dispersal by frugivorous animals. This mutualistic interaction depends largely on interaction‐relevant matching of functional traits (i.e. fruit size of plants and gape size of frugivores). With declines in large‐bodied animal populations, it is likely that fruit–frugivore interactions have eroded, leading to the loss of seed dispersal of large‐fruited plants. Such erosion could be especially evident in vulnerable island ecosystems such as those in the Caribbean, where most large‐bodied frugivore populations have collapsed due to human activities. Here, we aim to understand the consequences of this decline by first quantifying gaps in frugivory function between common, smaller frugivores (birds, smaller reptiles, and bats) and rarer or regionally extinct, larger reptiles (Cyclura spp. and Chelonoidis spp.) in the Caribbean archipelagos. We then assess the benefits of reestablishing these interactions by determining the effects of large reptile ingestion on seed germination for 10 fruiting species, representing a range of fruit sizes, native to the Caribbean. We found that there are significant gaps in frugivory function, with smaller frugivores having many times smaller mean gape sizes than larger reptiles. Furthermore, we found that most fruiting species used in this study could germinate after being consumed by large reptiles, with two species having their germination speed significantly accelerated post‐ingestion. These results indicate that fruiting plants could benefit from reestablishing frugivorous interactions between larger reptiles and fruiting plants. Given the existing gap in frugivory function, additional attention should be given to the possibility of rewilding defaunated islands to restore plant–frugivore networks.

Genetic resources of the genus Prunus L. and their role in stone fruit breeding

Stone fruits such as apricot, cherry plum, cherry, peach, plum, and sweet cherry are highly popular in the Russian Federation. They are cultivated in the industrial gardens of large agricultural producers, as well as the plantings on farms and household plots. The fruits of these species can be consumed fresh for a considerable period of time. The application of some processing methods (cooling, freezing, and storage in a special atmosphere) significantly extends this period. Stone fruits are also suitable for producing a wide variety of processed products. The biochemical composition of fruits determines their high energy value and dietary properties. The representatives of the genus Prunus L. exhibit great genetic diversity. Due to their high polymorphy, they cover a large area. In regions with favorable weather and climatic growth conditions, stone fruits constitute the main industrial varieties. High requirements for industrial varieties determine the relevance of breeding improvement of available varieties. Representatives of the genus Prunus are characterized by a long juvenile period, different ploidy of species, high incompatibility, as well as heterozygosity for a large number of traits with a comparatively small number of identified genes. This fact significantly complicates genetic studies. The assortment of stone fruit crops in central Russia was renewed in several main directions. Most varieties were created through intervarietal crosses within a species. The current breeding work is aimed at creating new stone fruit species, as well as at improving the existing assortment. Along with the crossing of geographically distant varieties within a species, distant hybridization is one of the promising directions. In this way, new cultivated species were created, e.g., Russian plum (P. rossica Erem.), which is widely used in plantings. Such varieties are characterized by an attractive appearance, large size, pleasant aroma, and great flavor of fruits, as well as resistance to frost and rotting.

Development of a deep-learning phenotyping tool for analyzing image-based strawberry phenotypes.

In strawberry farming, phenotypic traits (such as crown diameter, petiole length, plant height, flower, leaf, and fruit size) measurement is essential as it serves as a decision-making tool for plant monitoring and management. To date, strawberry plant phenotyping has relied on traditional approaches. In this study, an image-based Strawberry Phenotyping Tool (SPT) was developed using two deep-learning (DL) architectures, namely "YOLOv4" and "U-net" integrated into a single system. We aimed to create the most suitable DL-based tool with enhanced robustness to facilitate digital strawberry plant phenotyping directly at the natural scene or indirectly using captured and stored images. Our SPT was developed primarily through two steps (subsequently called versions) using image data with different backgrounds captured with simple smartphone cameras. The two versions (V1 and V2) were developed using the same DL networks but differed by the amount of image data and annotation method used during their development. For V1, 7,116 images were annotated using the single-target non-labeling method, whereas for V2, 7,850 images were annotated using the multitarget labeling method. The results of the held-out dataset revealed that the developed SPT facilitates strawberry phenotype measurements. By increasing the dataset size combined with multitarget labeling annotation, the detection accuracy of our system changed from 60.24% in V1 to 82.28% in V2. During the validation process, the system was evaluated using 70 images per phenotype and their corresponding actual values. The correlation coefficients and detection frequencies were higher for V2 than for V1, confirming the superiority of V2. Furthermore, an image-based regression model was developed to predict the fresh weight of strawberries based on the fruit size (R2 = 0.92). The results demonstrate the efficiency of our system in recognizing the aforementioned six strawberry phenotypic traits regardless of the complex scenario of the environment of the strawberry plant. This tool could help farmers and researchers make accurate and efficient decisions related to strawberry plant management, possibly causing increased productivity and yield potential.

Combining Ability and Hybrid Breeding in Tunisian Melon (Cucumis melo L.) for Fruit Traits

A half-diallel cross study of seven melon inbred lines was carried out. The seven parents and their 21 F1 hybrids were evaluated for precocity of maturity, average weight per fruit, and fruit quality (fruit size, rind thickness, and soluble solids). The Diallel analysis was investigated for breeding values of these melon genotypes via general and specific combining ability, relationships between general and specific combining ability, and heterosis for the evaluated traits. The analysis of variance of the traits evaluated indicated highly significant differences among genotypes, suggesting the presence of adequate genetic variation for breeding. Additive genetic effects were most important with respect to fruit weight, while genetic dominance and epistasis effects mainly controlled fruit quality traits (fruit size, rind thickness, and TSS). Parent 1 (P1) and parent 3 (P3) had significant positive general combining ability effects for fruit weight. Also, P3 had positive general combining ability effects for fruit length and diameter, and cavity diameter. P3 was found to show maximum significant GCA in the desirable direction for all the traits except for TSS. Evaluation of heterosis (%) revealed that hybrid P1 × P3 can be considered as the best-performing hybrid for average fruit weight, TSS, and precocity, which also exhibited the highest positive and significant SCA effect for these traits. These results suggested that, among the melon genotypes studied, there is the potential to generate superior new varieties in hybrid production.

Dynamic Compressive Stress Relaxation Model of Tomato Fruit Based on Long Short-Term Memory Model.

Tomatoes are prone to mechanical damage due to improper gripping forces during automated harvest and postharvest processes. To reduce this damage, a dynamic viscoelastic model based on long short-term memory (LSTM) is proposed to fit the dynamic compression stress relaxation characteristics of the individual fruit. Furthermore, the classical stress relaxation models involved, the triple-element Maxwell and Caputo fractional derivative models, are compared with the LSTM model to validate its performance. Meanwhile, the LSTM and classical stress relaxation models are used to predict the stress relaxation characteristics of tomato fruit with different fruit sizes and compression positions. The results for the whole test dataset show that the LSTM model achieves a RMSE of 2.829×10-5 Mpa and a MAPE of 0.228%. It significantly outperforms the Caputo fractional derivative model by demonstrating a substantial enhancement with a 37% decrease in RMSE and a 36% reduction in MAPE. Further analysis of individual tomato fruit reveals the LSTM model's performance, with the minimum RMSE recorded at the septum position being 3.438×10-5 Mpa, 31% higher than the maximum RMSE at the locule position. Similarly, the lowest MAPE at the septum stands at 0.375%, outperforming the highest MAPE at the locule position by a significant margin of 90%. Moreover, the LSTM model consistently reports the smallest discrepancies between the predicted and observed values compared to classical stress relaxation models. This accuracy suggests that the LSTM model could effectively supplant classical stress relaxation models for predicting stress relaxation changes in individual tomato fruit.

Identification of SNP Markers and Candidate Genes Associated with Major Agronomic Traits in Coffea arabica.

Genome-wide association studies (GWASs) allow for inferences about the relationships between genomic variants and phenotypic traits in natural or breeding populations. However, few have used this methodology in Coffea arabica. We aimed to identify chromosomal regions with significant associations between SNP markers and agronomic traits in C. arabica. We used a coffee panel consisting of 195 plants derived from 13 families in F2 generations and backcrosses of crosses between leaf rust-susceptible and -resistant genotypes. The plants were phenotyped for 18 agronomic markers and genotyped for 21,211 SNP markers. A GWAS enabled the identification of 110 SNPs with significant associations (p < 0.05) for several agronomic traits in C. arabica: plant height, plagiotropic branch length, number of vegetative nodes, canopy diameter, fruit size, cercosporiosis incidence, and rust incidence. The effects of each SNP marker associated with the traits were analyzed, such that they can be used for molecular marker-assisted selection. For the first time, a GWAS was used for these important agronomic traits in C. arabica, enabling applications in accelerated coffee breeding through marker-assisted selection and ensuring greater efficiency and time reduction. Furthermore, our findings provide preliminary knowledge to further confirm the genomic loci and potential candidate genes contributing to various structural and disease-related traits of C. arabica.

Seaweed-based biostimulants improves quality traits, postharvest disorders, and antioxidant properties of sweet cherry fruit and in response to gibberellic acid treatment

The main aim of this research was to determine whether seaweed-based biostimulants (BIO) have the potential to offset the delaying of fruit maturation and improve fruit quality and antioxidant properties in gibberellic acid (GA3)-treated cherries. Compared to the control, 5 g L−1 BIO applied twice at pit hardening (PH) and straw color (SC) or 3 times at PH, SC, and 1 week before harvest (1WBH) in mid-maturing ‘Bing’ cherries accelerated color development, increased soluble solids content (SSC), titratable acidity, total phenolics (TP), and DPPH radical scavenging activity at harvest. However, these treatments resulted in smaller and softer fruit. For late-maturing ‘Lapins’ cherries, BIO had no effect on fruit coloration, but increased the levels of antioxidants and antioxidant capacity at harvest, especially in 3 applications. Spraying 5 g L−1 BIO 3 times plus a single application of 10 mg L−1 GA3 at PH on ‘Bing’ cherries effectively increased fruit firmness (FF) and size, but showed a strong delaying effect on color development and SSC at harvest, and reduced resistance to disorders after 4 weeks of storage at 0°C if the combination-treated fruit were late harvested. Decreasing GA3 concentration from 10 to 5 mg L−1, increasing BIO concentration from 5 to 10 g L−1, and extending the harvest date by 5 d could impair the delaying effect of GA3 on fruit maturation, restore the normal fruit size, reduce the rates of decay, stem browning (SB), and surface pitting (SP), and maintain high FF and DPPH radical scavenging activity. In conclusion, pre-harvest 3 applications of 10 g L−1 BIO and 5 mg L−1 GA3 once at PH have the potential to curtail the GA3’s inhibition on fruit maturation, extend the harvest window, improve fruit quality, and increase antioxidants and antioxidant capacity in ‘Bing’ cherries.

Forest cover, tree structure, and fruit size as predictors of fruit consumption by birds in two tropical trees from southern Mexico

We evaluate the effect of some variables related to fruit morphology, tree structure, and forest cover on fruit consumption by birds in the tree species Conostegia xalapensis (Melastomataceae) and Bursera simaruba (Burseraceae), in a semi-humid forest of southern Mexico. Foraging observations were made in 20 trees per species from November 2020 to June 2021. We recorded a total of 18 and 22 bird species consuming the fruits of B. simaruba and C. xalapensis, respectively. Flycatchers preferred fruits of B. simaruba, while thrushes largely consumed fruits of C. xalapensis. For large birds, crop size and foliar height diversity were the most influential variables in the removal of B. simaruba fruits, while small birds were positively correlated with the foliar coverage. For C. xalapensis, forest cover negatively influenced fruit consumption by large birds, while the fruit polar diameter had a positive effect on fruit consumption by small birds. Fruit consumption of C. xalapensis by specialist birds showed a positive relationship with forest cover, while the generalists showed a negative relationship. Decreased fruit removal was observed for B. simaruba by both specialist and generalist birds in forest landscapes. Our results can help understand the drivers of the frugivore-plant relationship in semi-humid tropical forests.

Physiological and biochemical characterisation of split and healthy Daisy mandarin (Citrus reticulata Burm.) fruits

ABSTRACT Fruit splitting is a prevalent physiological disorder that has a significant impact on Daisy mandarin fruit production, posing challenges to farmers in terms of productivity and economic viability. Despite its impact, no prior research on fruit splitting in Daisy mandarin has been conducted. This study aimed to assess the effect of fruit splitting on quality, morphological characteristics, biochemical composition and nutrient content in Daisy mandarin. In 2022, a comprehensive analysis was conducted on both split and healthy Daisy mandarin fruits, budded on Rough lemon rootstock, to investigate their morphological characteristics, biochemical characteristics, mineral content and cell wall components. Additionally, the study examined the activity of cell wall-degrading enzymes, such as peroxidase (POD), cellulase (Cx) and polygalacturonase (PG). The Results indicated that split fruits exhibited larger fruit size and weight and increased water content in both the fruits and peel compared to healthy fruits. However, split fruits had thinner peel thickness and lower peel content. The peels of split fruits also contained higher level of total soluble sugars, amino acids, and proline content. Furthermore, the peels of split fruits displayed much higher activity of cell wall-degrading enzymes than those of healthy fruits. The nutrient analysis of the split fruits revealed a decrease in boron, calcium and potassium content in the peel compared to healthy fruits. The study provides crucial insights into the mechanisms underlying fruit splitting, identifying biochemical and physiological differences between split and healthy fruits. These findings offer valuable information for developing strategies to mitigate fruit splitting, enhancing fruit quality and reducing economic losses for citrus growers. Future research should explore the genetic and environmental factors contributing to fruit splitting and investigate potential interventions to improve nutrient management and fruit integrity in Daisy mandarin cultivation.

Irrigation scheduling for high value vegetable crops grown under protected cultivation in the hilly ecosystem of north-east India

Irrigation scheduling plays a vital role in the efficient utilization of water to obtain optimum yield, particularly for high value crops grown under protected conditions. The present experiment was conducted during 2020–22 at Horticulture Experimental Farm, ICAR-Research Complex for North Eastern Hill Region, Umiam, Meghalaya to standardize the irrigation scheduling (IS) (5, 7, and 10-days interval) in high-value vegetable crops [tomato (Solanum lycopersicum L.), capsicum (Capsicum annuum L.) and king-chilli (Capsicum chinense Jacq.)] grown under naturally ventilated low-cost polyhouse in the mid-hill conditions of Meghalaya. The results revealed a significant effect of IS on plant growth (reduction in plant height, leaf area) and yield attributes (fruit setting, fruit size, fruit weight and total yield) of the crops with an increase in level of moisture stress. The highest yield of tomato (82.7 t/ha), capsicum (40.8 t/ha) and king-chilli (11.8 t/ha) was recorded in the 5-day interval of IS and on increasing the IS interval to 7-days, the yield decreased by 28.7, 36.1 and 35.7%, respectively. Among the crops, capsicum was found to be more sensitive to water stress, followed by king-chilli and tomato. Among the crops, water productivity with respect to irrigation water was maximum in tomato (60.0 g/kg) followed by capsicum (17.2 g/kg) and king-chilli (10.0 g/kg). Among the varieties grown, Megha Tomato-3 of tomato, hybrid Mahabharat of capsicum and landrace Red Long of king-chilli were found superior for growth and yield attributes at different levels of moisture regime. The farmers of the region can get higher yield using identified varieties with irrigation at 5-days intervals.

Functional mechanisms underlying the persistence of Opuntia ficus-indica in a Mediterranean-type ecosystem after fire

Changes in fire regime can favor invasive plants in Mediterranean-type ecosystems. The goal of this experiment was to understand the post-fire dynamics of the invasive cactus, Opuntia ficus-indica, by assessing the contribution and impact of clonal propagation and sexual reproduction on the recruitment of this species after fire. The number of O. ficus-indica new clones and seed-derived plants was estimated after a burn event in a natural area located in the western Mediterranean (Catalonia, NE Spain). Functional stress markers, relative growth rate, and contents of both growth- and stress-related phytohormones were measured. Furthermore, remaining plants damaged by fire were evaluated regarding fruit size, seed number, and viability, as well as other reproductive traits. Results showed that 95 % of the new recruits in the burned area were clones. Clones showed a higher water and chlorophyll content than seed-derived plants. The relative growth rate was consequently higher in clones than in seed-derived plants, which was also associated with higher contents of growth-related hormones (cytokinins and gibberellins) in the former. Furthermore, seeds produced by burned plants exhibited a thicker funicular envelope compared to seeds from unburned plants. It is concluded that, although clonal propagation was the main reproductive strategy observed after fire, its combination with sexual reproduction and efficient physiological strategies of survival guarantees persistence of this invasive plant species in burned areas due to an effective and fast recovery in cactus cover in the short term while contributing to the genetic variability in the population in the long term.

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.