Large Fruit Research Articles

Wild pear (Pyrus pyraster (L.) Burgsd.) fruit and seed morphology depending on fruit size

The current study aims to evaluate the effects of fruit size of wild pear (Pyrus pyraster (L.) Burgsd.) on morphological fruit and seed traits. Wild pear fruit was collected from 10 trees in the area of Žumberačko gorje in the fall of 2022. The fruit was randomly collected from the ground and divided into three groups according to their weight (small (<10 g), medium (10 – 15 g) and large (>15 g)). Fruit size had a significant effect on the following morphological traits: fruit weight, fruit length, fruit width, the number of filled seeds, the weight of fresh seeds per fruit, the weight of 1 fresh seed and the weight of air-died seed, while no significant difference was found for fruit shape index, the number of empty seeds, the weight of 1 air dried seed and the share of seed dry matter. For all the aforementioned traits where the difference was significant, large fruit had significantly highest values, while in most cases (with the exception of the weight of 1 fresh seed), medium fruit had significantly higher values than small fruit. Comparing the correlation coefficients between different fruit size groups, it is evident that higher fruit size traits had a significant effect on the number of filled seeds in medium and large wild pear fruit only. In addition, it is visible that fruit weight and width, and not fruit length, had of the largest impact on the number of filled seeds. The principal component analysis revealed 3 significant principal components with eigenvalues greater than 1, which explained 75.88% of the total variability. It was shown that large fruit distinguish themselves from small and partly between medium by F1 axis. F1 was mainly influenced by fruit weight, fruit length, fruit width, the number of filled seeds, the weight of fresh seeds per fruit and the weight of air-dried seed per fruit. Based on the results obtained from this study, it can be concluded that for nursery production of wild pear seedlings bigger fruit should be used due to the higher number of filled seeds.

MICROMORPHOLOGICAL STUDIES (ACHENE / CYPSELA) ON SELECTED ASTERACEAE TAXA NATIVE TO TURKIYE

With this study fruit width-length measurements, weights and surface morphologies of some taxa belonging to Asteraceae family distributed in Türkiye were studied. The aim of the study was to reveal the fruit morphological characteristics and differences between the taxa of Tragopogon buphthalmoides, Dittrichia viscosa, Dittrichia graveolens, Tripleurospermum caucasicum, Kemulariella caucasica, Leontodon hispidus subsp. hispidus, Jurinea consanguinea and Jurinea moschus. Widths and lengths of the fruits were measured with Leica EZ4 microscope and digital caliper. Fruit weights were weighted out with Dikomsan precision scales. The stereomicroscope to determine the morphological characteristics of the fruits was also used. Scanning Electron Microscopy (SEM) in USKIM (Center for University and Industry Collaboration) was used to determine the surface morphology of the fruits. The smallest fruits were determined in Dittrichia graveolens (0.40 mm wide and 1.23 mm long), while the largest fruits were determined in Tragopogon buphthalmoides (25.88 mm long and 1.62 mm wide). The heaviest fruits were measured in Jurinea consanguinea (0.0065 gr) and the slightest fruits in Dittrichia graveolens (0.000062 gr) taxa.

Black currant cultivars, developed at the Polli Horticultural Research Center (Estonia), in Northwest Russia

Background. Introduction of new foreign cultivars makes it possible to expand the limits of the genetic potential of the VIR collection. A comprehensive study of such germplasm accessions is important for identifying sources of traits useful for breeding and the best cultivars for practical utilization. Materials and methods. Eight black currant cultivars released in Estonia were studied from 2015 through 2023 at Pushkin and Pavlovsk Laboratories of VIR. Conventional methods were used to test their adaptability and assess their main productivity indicators and berry quality. The resulting data were statistically processed in Microsoft Excel according to the guidelines by B. A. Dospekhov. Results and conclusion. The studied cultivars appeared well adapted to the environments of Northwest Russia. The heat supply in Leningrad Province is optimal for their cultivation. Good adaptability, synchronized fruit ripening, stable yields, and fine taste of berries were demonstrated by cvs. ‘Almo’ (k-44169), ‘Albos’ (k-44167), ‘Elo’ (k-44171), ‘Karri’ (k-44172), ‘Mulgi Must’ (k-38061), ‘Musti’ (k-44173), and ‘Varmas’ (k-44174). They are recommended for amateur gardens in Northwest Russia. Cv. ‘Karri’ (k-44172) is a promising source of such traits as good self-fertility, large fruit size, stable yield, well-balanced taste, high anthocyanin content in berries, and resistance to American powdery mildew and gall mite. Cv. ‘Varmas’ is a source of earliness, high self-fertility, and dessert taste of berries.

Specialized seed dispersal in Neotropical Vanilla reveals fruit unpalatability to omnivores.

Flowering plants are essentially sessile organisms that disperse their genes through pollination, expanding their areas of occurrence through seed dispersal. In orchids, seed dispersal is commonly mediated by air currents. Conversely, members of several genera have evolved seeds adapted to endozoochory. This is the case for Vanilla, the most economically important genus in the orchid family. The role of indehiscent fruits in the attraction and rewarding of Vanilla seed dispersers was investigated based on field observations, analysis of fragrances, reward substances, and investigation of seed viability through the digestive tract. Indehiscent Vanilla fruits are consumed exclusively by herbivores, i.e. agoutis. Besides providing nutritional rewards, the fruits are rich in polyphenols that are unpalatable to omnivores. The most dominant compound in fruits is attractive only to agoutis. This is the first study showing synzoochory in Orchidaceae and specificity of seed dispersal in orchids. Indehiscent fruits may have evolved early in Neotropical Vanilla in response to selection pressures mediated by large herbivores as the genus emerged ca. 34 Mya in South America, concomitantly with megafauna diversification in the Oligocene. Extinction of the megafauna during the Pleistocene has left agoutis as inheritors of seed dispersal in species with large fleshy fruits. Apart from the effects on omnivores, this study shows that indehiscent fruits of V. chamissonis are consumed exclusively by agoutis, providing the first evidence of target mutualism in orchid seed dispersal.

Урожайность гибридов смородины черной в Центральной Якутии

Abstract. A study was carried out of the yield and large-fruited original material of black currant in a breeding nursery in the conditions of Central Yakutia. The purpose is to identify sources of high yield and large-fruited black currant hybrids for use in breeding. The objectives of the study included high-yielding hybrids of black currant to carry out crop accounting and identify; determine the mass of berries in hybrids and select sources of large fruit. Methods. The research was carried out according to the generally accepted methodology “Program and methodology for the selection of fruit, berry and nut crops” (Oryol, 1995). Scientific novelty. For the first time, new sources of black currant productivity have been identified for breeding in Yakutia. Results. In the breeding nursery, 10 sources of high yield (more than 10 t/ha) and 4 sources of large-fruited black currant hybrids from various genetic groups were selected. Among them, the hybrid 3-7-18 (Podarok Kuzioru × Khara Kytalyk), a derivative of three subspecies of black currant and low-flowering currant with a yield of 18.9 t/ha, is distinguished by the characteristics of early fruiting, high and stable yield. Of 4 black currant hybrids - 3-19-18 (Podarok Kuzioru × Myuryuchana), 3-2-18 (Podarok Kuzioru × Khara Kytalyk), 2-18-18 (Podarok Kuzioru × Yakutskaya) and 1-17-18 (Ksyusha × Yakutskaya) was characteristic large fruiting. The weight of 1 berry ranged from 1.53 to 1.70 g. A negative relationship was revealed between the indicators of yield and large-fruited black currant (r = –0.47), as a result of mathematical processing of experimental data The identified sources of high yield and large fruit will be used in the selection of black currants in Central Yakutia to create new source material and further study them according to a set of traits.

Study on the Bioactive Constituent and Mineral Elements of the Tibetan Medicine E'seguo from Different Regions of Ganzi Prefecture, China.

The Tibetan medicinal fruit E'seguo originates from two species, Malus toringoides (Rehd.) Hughes and Malus transitoria (Batal.) Schneid, both unique to the Hengduan Mountains. These species are predominantly found in high-altitude regions of Ganzi Prefecture, Sichuan Province, particularly in the Xianshui River and Yalong River basins. Malus toringoides (Rehd.) Hughes is far more abundant in both resource quantity and distribution compared to Malus transitoria (Batal.) Schneid. However, the nutritional and medicinal differences between the two remain unclear, which significantly impacts the development and utilization of E'seguo resources. This study aimed to measure the mineral content, nutritional components, and medicinal properties of E'seguo from 12 different regions of Ganzi Prefecture to explore the quality differences between these two species and across different regions. ICP-MS (Inductively Coupled Plasma Mass Spectrometry) was used to determine the mineral content, ultraviolet-visible spectrophotometry and potentiometric titration to analyze nutritional indicators, and HPLC (High-Performance Liquid Chromatography) to measure the medicinal components L-malic acid and 2-O-β-D-glucopyranosyl-L-ascorbic acid (AA-2βG). Results indicate that Malus transitoria (Batal.) Schneid contains higher levels of K, Ca, Zn, Mg, and Cu compared to Malus toringoides (Rehd.) Hughes, which has higher Fe and Mn content. Malus toringoides (Rehd.) Hughes from the Kangding and Litang regions showed the highest mineral content, with mineral elements primarily influencing polysaccharide levels, according to Mantel analysis. Nutritional and medicinal analyses revealed that Malus toringoides (Rehd.) Hughes outperformed Malus transitoria (Batal.) Schneid in all metrics except for the sugar-acid ratio. Given the mineral content and taste, Malus transitoria (Batal.) Schneid is better suited for consumption, while Malus toringoides (Rehd.) Hughes has superior medicinal properties, making it more appropriate for medicinal use. In the Malus transitoria (Batal.) Schneid regions, both Luhuo and Daofu are in the Xianshui River basin, with Daofu County producing the higher quality fruit. Among the nine Malus toringoides (Rehd.) Hughes regions, the M10 (Tuoba Township, Ganzi County) near the Yalong River had the highest overall score, followed by M7 (Yade Township, Luhuo County) and M6 (Keke, Xiala Tuo Town, Luhuo County), both of which are near the Xianshui River. In summary, Malus transitoria (Batal.) Schneid generally has higher mineral content, but Malus toringoides (Rehd.) Hughes has larger fruit and higher medicinal value, making the latter more suitable as a medicinal resource. At the same time, the medicinal quality of Xianshui River fruit was higher in the two watersheds of Malus toringoides (Rehd.) Hughes.

Quantifying Temperature Effects on Plant Development Rates and Quality of Compact Container-grown Pepper

The mean daily temperature effects on plant development rates and quality of compact container-grown pepper were evaluated. Compact pepper cultivars Fresh Bites Yellow and Hot Burrito were grown in greenhouses at 18 to 26 °C (Expt. 1) and 20 to 30 °C (Expt. 2) under supplemental high-pressure sodium lighting and a 16-hour photoperiod. The number of days to first open flower, to first ripe fruit, and from flower to ripe fruit were measured and the development rates calculated by taking the reciprocal (e.g., 1/day). Temperature effects were predicted by fitting a nonlinear exponential function that included the base temperature (Tmin) and maximum developmental rate (Rmax) parameters. Plant quality attributes were measured during Expt. 2. As the temperature increased, the times to flower and fruit decreased (i.e., developmental rates increased) for both cultivars. The estimated Tmin was 13.3 °C for ‘Fresh Bites Yellow’, and that for ‘Hot Burrito’ was 9.3 °C, whereas the Rmax was similar between cultivars (averages of 0.0488 at flower, 0.0190 at fruit, and 0.0252 from flower to fruit). ‘Fresh Bites Yellow’ and ‘Hot Burrito’ grown at ≈25 °C had a relatively short crop time, compact canopy, large fruit size, and high number of fruits per plant at finish. Compact peppers are new crops being grown by greenhouse floriculture operations for their ornamental and edible value, and the information from this study can help growers schedule these crops to meet critical market windows and determine the impacts of changing the growing temperature on crop timing and quality.

Comparative fruit morphology of nine Psittacanthus Mart. (Santalales: Loranthaceae) mistletoe species occurring in Mexico

The genus Psittacanthus is distributed from Mexico to Argentina and contains c. 110 species. The large, lipid-rich, one-seeded fruits of Psittacanthus species frequently depend on frugivorous birds for seed dispersal; however, fruit morphology of Psittacanthus (Loranthaceae) mistletoes remain poorly studied. In this study we describe the fruit morphology of nine Psittacanthus species. Fruits were collected from the study sites in which mistletoe plants were inhabiting contrasting habitats and host tree species. The morphological characteristics of fruits by species were described and compared with the use of inclusion and staining techniques and light microscopy. Our results show that fruit size varies among species, with P. macrantherus having the largest fruits. Most fruits have an ellipsoid to ovoid shape, color of fruits transits from green when immature to red or purple before ripening to blackish or purplish black, with color variations observed in different species, and the cupular pedicel length varying among species. Fruit sections indicate the following parts: exocarp, viscin layer, seed coat and a dicotylar to polycotylar embryo, with P. schiedeanus having the highest cotyledon count. No endosperm is present in the studied species. Our results provide valuable information for further species comparisons regarding the lack of endosperm and polycotylar embryo. Additionally, interspecific variation in cotyledon number and seed coat highlights distinct processes, including the potential effects of environmental differences.

The Training Systems Affect Fruit Quality, Yield, and Labor Efficiency in Peach (P. persica L. Batsch)

In the Vase system, the most common training system for peach-growing countries for more than a century, light distribution to the canopy is uneven, and access to the canopy for pruning, thinning, and harvest labor is difficult. It is important to identify alternative systems to the Vase system considering the cultivar and growing environment to facilitate labor and enhance productivity and quality. In Türkiye, one of the important centers of peach growing worldwide, detailed research has yet to be published on the applicability of training systems alternative to the widely used Vase system. Therefore, this study aimed to evaluate the effect of different training systems (Vase, Catalan Vase, Quad-V, Tri-V) on growth, yield, fruit quality, and labor costs of peach cultivars (Extreme® 314, Extreme® 436, Extreme® 568). The experiment was conducted from 2017 to 2022. Although the distance between rows in all training systems is 5 m, the distance between trees on the row is determined as 4 m in Vase, 3 m in Catalan Vase, 2.5 m in Quad-V, and 2 m in Tri-V. In the experiment, vegetative development parameters, such as canopy volume, trunk sectional area, and the amount of winter pruning weights, differed according to the training system. In the final year, the Vase system, which produces the most pruning weight, generates 48.0% more pruning weight compared with the Tri-V system, which produces the least. Concerning yield per tree and hectare, trained to the Vase system yielded higher fruit per tree regardless of cultivar, while the Quad-V and Tri-V systems yielded more fruit per hectare. The training system and cultivar affected the fruit size; the largest fruits were obtained from the Extreme® 568 cultivar trained according to the Vase system. The most time needed for winter pruning was obtained from the Vase (79.4 min/tree) system, and the Tri-V (57.4 min/tree) and Quad-V (60.3 min/tree) systems required the least time. The Catalan Vase (31.1 min/tree) system required the least time for summer pruning. The most fruit harvest in an hour was obtained from the trees trained according to the Tri-V (164.5 kg/h) and Quad-V (132.02 kg/h) systems. These results suggest that Quad-V and Catalan Vase systems performed well and could be alternatives to the Vase system.

Adaptability of Phytophthora capsici Resistant Bell Pepper Cultivars in Southern Georgia

Phytophthora capsici (PCap), which causes Phytophthora root rot, is the most destructive soilborne pathogen for bell pepper (Capsicum annuum L.) production in Georgia, USA. Extensive host range, persistence of inoculum in the soil, and lack of effective chemical control methods make this disease particularly difficult to manage. Resistant cultivars offer a practical solution to manage PCap in affected bell pepper fields. However, most commercial cultivars resistant to PCap are predominantly grown in the northeastern United States. This research aimed to screen commercial bell pepper cultivars for resistance to PCap, marketable yield, fruit size distribution, and overall adaptability for production within the largest growing areas in southern Georgia. Field trials were conducted during Spring 2022 and 2023 in commercial growers’ fields with a known history of PCap infestation to evaluate PCap-resistant bell pepper cultivars across four trials conducted in the three counties (Colquitt, Echols, and Lowndes) responsible for ∼78% of bell pepper production in Georgia. Eleven cultivars were evaluated: nine that claimed PCap resistance and two widely grown PCap susceptible cultivars included for comparison. Phytophthora root rot incidence was very low in these research trials. However, there were significant differences in total yields, marketable yields, fruit size, and unmarketable yields. On the basis of marketable yields for jumbo, extra large, and large-sized fruit, we recommend the PCap-resistant cultivars PS 0994-1819, Paladin, and Mercer for fresh market bell pepper growers. Furthermore, ‘Revolution’ is recommended for processor growers due to higher jumbo-sized fruit yields and lower quality and higher pancaking for the spring season in southern Georgia, USA. Newer cultivars Tarpon and Nitro have a more desirable disease-resistance package; however, ‘Nitro’ had small-sized fruit, and ‘Tarpon’ tended to have lower total yields than current commercial standards.

Soil pH and organic matter: Key edaphic factors in sustaining optimum yield and quality of pomelo fruit

Identifying the soil properties associated with crop yield and quality variation is crucial for developing sustainable agronomic strategies. However, such information on pomelo production is scarce. Hence, forty independent sites in the primary pomelo production areas of Pinghe County were selected to investigate the influence of soil properties on pomelo yield and quality, and to provide reference for future soil management strategies. The results showed positive correlations between pomelo yield and soil pH, along with exchangeable calcium and magnesium, but this comes at the expense of fruit flavor quality. Meanwhile, soil organic matter positively influenced fruit flavor quality. Furthermore, a significant positive effect on fruit nutritional quality was noted across various soil properties, except for organic matter and available phosphorus concentration. A random forest model was used to predict pomelo yield, flavor quality, and nutritional quality based on soil properties and yielded R2 values of 0.50, 0.60, and 0.50, respectively. Partial least squares regression and structural equation modeling identified soil pH and organic matter as pivotal pomelo yield and quality determinants. The categorization of samples into four groups based on differences in pH and organic matter highlighted that integrating soil acidification remediation with organic matter increased is essential for sustainable pomelo production. Overall, this study offers comprehensive insights into the effects of holistic soil management on achieving both high yield and quality in pomelo cultivation. Furthermore, these findings serve as valuable reference for advancing sustainable production practices across large fruit types beyond the pomelo.

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.

Comparison of modern raspberry varieties long cane

Relevance. Modern raspberry varieties (Rubus idaeus L.) have great potential for cultivation using Long Cane technology.Methods. The study compared raspberry varieties Ovation, Wengi, and Vajolet. Seedlings were obtained from root cuttings, then grown from April 2021 to July 2022 for the summer harvest and from April 2022 to October 2022 for the fall harvest.Results. It has been established that varietal characteristics and the fruiting period significantly affect the indicators. The largest fruits are in the Wengi variety (length 25.5 mm, diameter 24.3 mm, weight 7.2 g), the smallest are in the Ovation variety (length 22.2 mm, diameter 22.5 mm, weight 4.9 g). When observing varieties at different ripening periods, it was found that the fruit length (27.3 mm) and fruit weight (8.3 mm) during the summer fruiting period are maximum in the Wengi variety, and minimum in the Vajolet variety. The amount of sugar ranges from 11 to 13°Bx, the percentage of ripe fruits from 84.5 to 94.5. The difference between the Wengi and Ovation varieties in terms of vegetative characteristics at different growing periods has been reliably proven. During the summer fruiting period, the yield per shoot for Wengi was 2615 g, for Vajolet – 485 g. The Wengi variety was distinguished by its maximum length (27.3 mm) and fruit weight (8.3 g). Based on all the indicators, the most promising varieties for summer fruiting are Wengi and Vajolet, and for autumn fruiting – Ovation.

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.

How plant and insect host characteristics affect pepper weevil Anthonomus eugenii parasitism efficacy by the pteromalid Jaliscoa hunteri

The pepper weevil Anthonomus eugenii (Cano) (Coleoptera: Curculionidae) is an economically important pest of both field and greenhouse pepper crops, Capsicum annuum Linnaeus (Solanaceae) in North America. Among its natural enemies is the parasitoid wasp Jaliscoa (= Catolaccus) hunteri (Crawford) (Hymenoptera: Pteromalidae), whose potential control of A. eugenii appears promising but is currently unclear. We conducted controlled environment trials to quantify A. eugenii offspring emergence following exposure to J. hunteri, examining how parasitoid exposure period, weevil host life stage, pepper cultivar, fruit size and abscission status affect weevil-natural enemy dynamics. In pepper cultivar comparison trials, we identified a significant reduction in weevil offspring emergence from three different cultivars of ornamental peppers infested by A. eugenii, but no difference among them. In trials comparing wasp exposure period and weevil larval instar, pepper plants of one cultivar (Blaze) were exposed to A. eugenii adults, and subsequently to J. hunteri wasps for either three or seven days, when offspring weevils were either at the L1 or L3 instar. Offspring emergence was significantly reduced up to 62% when L3 but not L1 weevils were exposed to wasps for 7 days. Following this longer exposure period, significantly greater weevil suppression occurred in small (71.7%) versus large fruit (62.5%), with an additional 15.1% weevil suppression resulting from attached relative to abscised fruit. These results highlight the potential for J. hunteri as a biological control agent of A. eugenii on pepper crops, with particular value in commercial greenhouse production where wasp retention rates can be high.

Grafting onto Tomato Rootstocks Improves Outcomes for Dry-farmed Tomato

Vegetable grafting can mitigate the negative effects of drought on crop production. Dry farming, which is the production of crops without irrigation during a dry growing season, can result in lower yields, smaller fruit, and a higher incidence of blossom-end rot (BER), which is a physiological disorder associated with drought stress. To determine the effects of grafting on yield and fruit quality of dry-farmed tomato (Solanum lycopersicum), three years of trials were conducted using different scion–rootstock combinations and ungrafted controls. In 2020, grafting onto rootstocks ‘DRO141TX’ and ‘Fortamino’ resulted in greater total yield and average fruit weight and a lower BER incidence for dry-farmed tomato than grafting onto the rootstock ‘Shincheonggang’ or using ungrafted plants. In 2021, grafting onto the rootstock ‘DRO141TX’ again increased yields and average fruit weight and decreased BER incidence when compared with ungrafted plants (‘Fortamino’ was not tested). Interactions were detected between different scion–rootstock combinations in terms of the degree of reduction of necrotic BER (BER resulting in a large, sunken, grey or black spot, making the fruit unmarketable) when grafted onto ‘DRO141TX’, with the scion ‘Azoychka’ having a 69% reduction in necrotic BER and the scion ‘Astrakhanskie’ having a 93% reduction in necrotic BER. In 2022, an interaction was detected between the rootstocks and scions in terms of their effect on large fruit (>0.33 lb) yield, with ‘BHN 871’ grafted onto ‘Fortamino’ producing the highest yields of large fruit and ‘Big Beef’ grafted onto ‘Fortamino’ producing the lowest yields. Overall, grafting onto the rootstocks ‘DRO141TX’ or ‘Fortamino’ improved diverse dry-farmed tomato outcomes in the Willamette Valley of Oregon, USA.

Fruit Size as an Indicator of Fruit Drop in Huanglongbing-affected ‘Valencia’

Increased preharvest fruit drop rates and reduced fruit sizes are common symptoms associated with Huanglongbing (HLB) in sweet orange. Small fruit may be more likely to drop during preharvest fruit drop. The objective of the current study was to determine whether fruit size could be used as an indicator of the preharvest fruit drop likelihood. Nearly 1400 fruit were surveyed over the following three timepoints across two years: 11 Mar 2022, 15 Apr 2022, and 22 Mar 2023. Each fruit was evaluated to determine the equator and peduncle diameter, fruit detachment force (FDF), type of detachment (mechanically broken or abscission), and lopsidedness. The total soluble solids content was determined for a subset of fruit. The FDF was consistently lower in abscising fruit than in mechanically broken fruit, suggesting that the physiological process of abscission had begun in these fruit and that they were more likely to drop. The fruit diameter was significantly smaller in abscising fruit than in mechanically broken fruit on 11 Mar 2022 and 22 Mar 2023, but not on 15 Apr 2022. Similarly, the fruit diameter and FDF were also significantly and positively correlated, but this relationship was weaker at time points late in the season (closer to harvest). These findings suggest that small fruit are indeed more likely to drop early in the preharvest period. The abscising fruit had total soluble solids contents similar to those of the mechanically broken fruit. Therefore, we hypothesized that the smaller fruit ceased growing and are able to respond to abscission signals earlier than the larger fruit. Therefore, any strategies to mitigate fruit drop, such as the use of plant growth regulators, should be applied early in the season when the fruit are still actively growing. When growth ceases, the fruit are vulnerable to drop.

Characterization And Genetic Relationship of Several Tomato (Solanum lycopersicum L.) Genotypes from Various Regions

The research aims to obtain information about the morphological characters and genetic relationships of several tomato genotypes from various regions. The study was conducted from May to October 2023 at the Experimental Garden and Plant Breeding Laboratory, Faculty of Agriculture, University of Riau. The research used a randomized block design (RBD) consisting of eight genotypes and four repeats, and 32 experimental units were obtained. The observations were made to observe some qualitative characters. Qualitative data were analyzed using principal component analysis and cluster analysis to see genetic relationships. The results showed that the Magelang genotype (T27) had a high average plant fruit weight of 619.74 g, the Pane tongah (T24) had an average thick fruit flesh of 6.05 mm, the Silimakuta (T22) had an average large fruit size of 63.28 g. In contrast, the Purba (T25) had an average number of large planting fruits of 15.41 pieces. Grouping eight tomato genotypes based on clustering of MC1 and MC2 and cutting the dendrogram at a 90% similarity rate resulted in six groups. Group One consists of three genotypes, specifically Silimakuta (T22), Alahan Panjang (T26), and Magelang (T27). Group Two has Raya (T23), Group Three has Purba (T25), Group Four has Pane tongah (T24), group five has Servo F1 and group six has Ratna. The closest kinship based on the smallest euclidiean distance value is the Silimakuta (T22) and Alahan panjang (T26), with a value of 19.44. The genotypes with the farthest similarity are Raya (T23) and Purba (T25) because they have a 46.24 genetic distance

BIOESTIMULANTE Y TIEMPOS DE IMBIBICIÓN SOBRE LA GERMINACIÓN DE SEMILLAS DE MARACUYÁ (Passiflora edulis S., Passifloraceae

<p><strong>Background: </strong>Passion fruit (<em>Passiflora edulis</em> S.) is a tropical fruit of socio-economic interest in Peru, used as an ingredient in the food industry, esthetics and medicine. However, this crop has a low germination power, so it is necessary to carry out pre-germination treatments to increase the germination percentage and the initial development of the seedlings. <strong>Objective:</strong> to evaluate the effect of different biostimulants at 12 h and 24 h of hydration on passion fruit seed germination. <strong>Methodology: </strong>passion fruit seeds of large and round fruits, free of pathogens, were collected. The aryl-free seeds were treated: T0 (distilled water), T1 (sulfur 25 g/10 L), T2 (sulfur 50 g/10 L), T3 (biol 3%), T4 (biol 5%), T5 (cinnamon 25%), T6 (cinnamon 50%), T7 (buttermilk 25%) and T8 (buttermilk 50%) for 12 h and 24 h imbibition. The variables evaluated were: water absorbed, imbibition rate (IR), germination percentage (GP), germination speed (GS), germination index (GI), first day of germination (FDG). <strong>Results:</strong> The highest water absorption occurred in the first 9 hours. Treatments T4, T5 and T6 significantly improved the GP, GS, GI, FDG at 12 h imbibition. However, at 24 h imbibition these values decreased. GP presented a high positive correlation with GS and GI. Likewise, GS presented a high negative correlation with FDG. <strong>Implications: </strong>The use of biostimulants increases germination. <strong>Conclusions:</strong> Cinnamon extract at 25% and 50%, and biol 5% at 12 h of imbibition have significantly improved the variables evaluated compared to imbibition at 24 h. The positive correlation between the variables indicates a direct relationship between them.</p>

Genomic signatures of past megafrugivore‐mediated dispersal in Malagasy palms

Abstract Seed dispersal affects gene flow and hence genetic differentiation of plant populations. During the Late Quaternary, most fruit‐eating and seed‐dispersing megafauna went extinct, but whether these animals have left signatures in the population genetics of their food plants, particularly those with large, ‘megafaunal’ fruits (i.e. >4 cm—megafruits), remains unclear. Here, we assessed the population history, genetic differentiation and recent migration among populations of four animal‐dispersed palm (Arecaceae) species with large (Borassus madagascariensis), medium‐sized (Hyphaene coriacea, Bismarckia nobilis) and small (Chrysalidocarpus madagascariensis) fruits on Madagascar. We integrated double‐digest restriction‐site‐associated DNA sequencing (ddRAD) of 167 individuals from 25 populations with (past) distribution ranges for extinct (e.g., giant lemurs and elephant birds) and extant seed‐dispersing animals, landscape and human impact data, and applied linear mixed‐effects models to explore the drivers of genetic variation in Malagasy palms. Palm populations that shared more megafrugivore species in the past had lower genetic differentiation than populations that shared fewer megafrugivore species. This suggests that megafrugivore‐mediated seed dispersal in the past may have led to frequent gene flow among populations. In comparison, extant frugivore diversity only decreased genetic differentiation in the small‐fruited palm. Furthermore, genetic differentiation of all palm species decreased with landscape connectivity (i.e. environmental suitability, forest cover and river density) and human impact (i.e. road density), while migration rates of the small‐fruit palm increased with road density. Synthesis. Our results suggest that the legacy of megafrugivores regularly achieving long dispersal distances is still reflected in the population genetics of palms that were formerly dispersed by such animals. Furthermore, low genetic differentiation was possibly maintained after the megafauna extinctions through alternative dispersal (e.g. human‐ or river‐mediated), long generation times and long lifespans of these megafruit palms. Our study illustrates how species interactions that happened >1000 years ago can leave imprints in their population genetics.