Tree Fruit Research Articles

Changing climate risks for high-value tree fruit production across the United States

Abstract Climate change poses growing risks to global agriculture including perennial tree fruit such as apples that hold important nutritional, cultural, and economic value. This study quantifies historical trends in climate metrics affecting apple growth, production, and quality, which remain understudied. Utilizing the high-resolution gridMET dataset, we analyzed trends (1979-2022) in several key metrics across the U.S. – cold degree days, chill portions, last day of spring frost, growing degree days (GDD), extreme heat days (daily maximum temperature >34°C), and warm nights (daily minimum temperatures >15°C). We found significant trends across large parts of the U.S. in all metrics, with the spatial patterns consistent with pronounced warming across the western states in summer and winter. Yakima County, WA, Kent County, MI, Wayne County, NY—leading apple-producers—showed significant decreasing trends in cold degree days and increasing trends in GDD and warm fall nights. Yakima county, with over 48,870 acres of apple orchards, showed significant changes in five of the six metrics - earlier last day of spring frost, fewer cold degree days, increasing GDD over the overall growth period, and more extreme heat days and warm nights. These trends could negatively affect apple production by reducing the dormancy period, altering bloom timing, increasing sunburn risk, and diminishing apple appearance and quality. Large parts of the U.S. experience detrimental trends in multiple metrics simultaneously that indicate the potential for compounding negative impacts on the production and quality of apples and other tree fruit, emphasizing the need for developing and adopting adaptation strategies.

Challenges in harvesting and utilization of Ziziphus tree fruits in Ethiopia

Ziziphus tree species commonly known as “jujube” are wide sources of nutritious and socio-economically important fruits in arid and semi-arid regions of Asia and Africa. However, understanding of local communities’ engagement in harvesting and utilization of these fruits remains limited consequently undermining sustainable harvesting and broader utilization. Household interviews (HHIs), focus group discussions (FGDs) and key informants’ interviews (KIIs) were used to investigate the level of harvesting and utilization of fruits from different tree species of jujube in Ethiopia. Multiple linear and binary logistic regressions were utilized to investigate factors influencing the annual fruit yield per tree and to discern factors impacting the local community's capacity to grow and sell jujube, respectively. Fruit yield per tree, market involvement and the principal challenges to growing were found to vary among two study sites. Bosset district's yield exceeded Bati's by 0.87 times. Women and children played significant roles in fruit collection, sale and management. Less rainfall reduced annual yield by 33 kg per tree while planting seedlings instead of relying solely on naturally regenerated trees boosted yield by 42 kg per year. With each advancing year in age, older respondents were 0.04 times less likely to sell harvested jujube fruits. The increasing impact of pests, water shortage and cultural influences decreased community interest in growing jujube by factors of 1.15, 1.41 and 2 times, respectively. Suboptimal involvement in jujube cultivation, fruit harvest and market activities was frequently ascribed to inadequate community support, organizational oversight and depressed market prices. These findings highlight the need to enhance awareness, management and market access for jujube fruits to broaden community benefits in Ethiopia.

Effects of Tree Spacing and Branch Configuration on Production, Fruit Quality, and Leaf Minerals of ‘Aztec Fuji’ Apple Trees in a Tatura Trellis System Over 5 Years

Tree spacing and branch architecture are critical for the productivity of high-density orchards. The influence of two tree spacings of 45.7 cm × 366 cm and 91.4 cm × 366 cm each with two branch architectures or configurations of shortened branch (ShBr) or overlapped branch (OverBr) on tree growth, yield components, fruit quality, and leaf mineral nutrients in an ‘Aztec Fuji’ apple (Malus domestica Borkh.) orchard with a 60-degree Tatura trellis (V) system was studied over 5 years. Trees planted with 91.4-cm spacing had a significantly greater trunk cross-sectional area (TCSA), higher number of fruit and greater yield per tree, and greater cumulative yield efficiency than those of trees planted with 45.7-cm spacing during 2012–16. Tree spacing did not significantly affect fruit weight and firmness at harvest or after storage. However, trees planted with 91.4-cm spacing always had higher fruit color, sunburn, fruit russet, and watercore at harvest and a higher soluble solids concentration but lower fruit bitter pit at harvest and after storage compared to those of trees with 45.7-cm spacing. These differences were often significant. Trees with 45.7-cm spacing had significantly higher leaf concentrations of potassium, iron, copper, and manganese and relatively higher leaf zinc than those of trees with 91.4-cm spacing. Trees trained according to ShBr architectures had a relatively larger TCSA than those of trees with an OverBr configuration every year. Branching architectures did not affect the number of fruits per tree, yield per tree, yield per hectare, yield efficiency, or biennial bearing index in any year. Trees with a ShBr architecture had significantly larger fruits than those with an OverBr system every year and over the 5 years. Trees with a ShBr architecture had higher average leaf fresh and dry weights and calcium concentration but a similar percentage of dry weight compared to those of trees with an OverBr architecture.

Isolation and Identification of Pear Ring Rot Fungus and Resistance Evaluation of Different Pear Varieties

Botryosphaeria dothidea is a significant plant pathogen responsible for causing ulcers, wilt, and fruit decay across a wide range of host plants. One notable fungal disease attributed to B. dothidea is pear tree ring rot, which currently ranks among the most severe diseases affecting pear trees in China. This pathogen primarily targets branches and fruits, occasionally impacting leaves as well, leading to tree weakening, fruit rot, and leaf drop. The annual repercussions of this disease severely affect both the yield and quality of pear fruits, thereby impeding the healthy development of the pear industry. Recent studies have indicated that other species within the B. dothidea complex can also induce pear ring rot; however, specific physiological strains of B. dothidea remain unreported. Consequently, this study collected tissues from pear trees infected with ring rot from orchards located in Liaoning, Hebei, Shandong, and other regions throughout China. Through morphological characterization combined with pathogenicity assessments and DNA sequence comparisons involving partial internal transcribed spacer (ITS), translation elongation factor (TEF), and β-tubulin (TUB) genes, 21 strains belonging to the Botryosphaeria spp. were identified. These 21 strains served as research subjects for inoculating dormant annual branches from 30 germplasm resources of pear trees in vitro. The results demonstrated that all tested strains could induce lesions on the branches which were characterized by dark brown spots. Furthermore, inoculation experiments involving these 21 strains were conducted to evaluate the resistance levels of various pear varieties against ring rot disease. The resistance was assessed by inoculating different isolates onto distinct pear varieties; this approach established the criteria for evaluating resistance while minimizing identification errors stemming from the variable responses exhibited by certain varieties towards individual strains. Ultimately, this study aims to provide a theoretical foundation for effective prevention and treatment strategies against pear ring rot.

Impact of Buriti Oil from Mauritia flexuosa Palm Tree on the Rheological, Thermal, and Mechanical Properties of Linear Low-Density Polyethylene for Improved Sustainability

Recent advancements highlight the utilization of vegetable oils as additives in polymeric materials, particularly for replacing conventional plasticizers. Buriti oil (BO), extracted from the Amazon’s Mauritia flexuosa palm tree fruit, boasts an impressive profile of vitamins, minerals, proteins, carotenoids, and tocopherol. This study investigates the impact of incorporating buriti oil as a plasticizer in linear low-density polyethylene (LLDPE) matrices. The aim of this research was to evaluate how buriti oil, a bioactive compound, influences the thermal and rheological properties of LLDPE. Buriti oil/LLDPE compositions were prepared via melt intercalation techniques, and the resulting materials were characterized through thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), mechanical property testing, and contact angle measurement. The addition of buriti oil was found to act as a processing aid and plasticizer, enhancing the fluidity of LLDPE polymer chains. TGA revealed distinct thermal stabilities for buriti oil/LLDPE under different degradation conditions. Notably, buriti oil exhibited an initial weight loss temperature of 402 °C, whereas that of LLDPE was 466.4 °C. This indicated a minor reduction in the thermal stability of buriti oil/LLDPE compositions. The thermal stability, as observed through DSC, displayed a nuanced response to the oil’s incorporation, suggesting a complex interaction between the oil and polymer matrix. Detailed mechanical testing indicated a marked increase in tensile strength and elongation at break, especially at optimal concentrations of buriti oil. SEM analysis showcased a more uniform and less brittle microstructure, correlating with the enhanced mechanical properties. Contact angle measurements revealed a notable shift in surface hydrophobicity, indicating a change in the surface chemistry. This study demonstrates that buriti oil can positively influence the processability and thermal properties of LLDPE, thus expanding its potential applications as an effective plasticizer.

Klasifikasi Tingkat Kemanisan Buah Kersen Berdasarkan Fitur Warna NTSC Menggunakan Jaringan Syaraf Tiruan Berbasis Pengolahan Citra Digital

<em><span lang="EN-US">The fruit of the calabura tree (Muntingia calabura) is a small red fruit originating from the Prunus genus, often found along roadsides. This fruit contains numerous nutrients beneficial for bodily health, serving as a highly potential source of nutrition. Presently, a challenge exists in determining the sweetness level of calabura fruit, relying heavily on manual human assessment. The development of classification utilizing technology is considered a crucial step. Previous research has concentrated on classifying various objects using RGB, HSV, YCbCr color feature extraction. However, it was observed that RGB, HSV, YCbCr color features are not universally suitable, particularly for calabura fruits. Hence, this study employs a method of classifying the sweetness level of calabura fruit based on NTSC color features using a Digital Image Processing-based Artificial Neural Network (ANN). This approach leverages color-based image processing features. The research involves several stages, starting from acquiring 300 calabura fruit images with 3 levels of classification to the classification process utilizing Backpropagation in the ANN. Multiple training and testing scenarios were conducted to select feature combinations with the highest accuracy and fastest computational time. Results revealed that the most effective feature used was the NTSC color feature as a skin characteristic parameter. Based on training outcomes using 210 training images, the accuracy reached 100% with a computational time of 1.66 seconds per image. Meanwhile, testing with 90 sample images showed an accuracy of 94% with a computational time of 4.23 seconds per image. Thus, it can be concluded that the employed method successfully classifies the quality of calabura fruit images based on color features and skin characteristics.</span></em>

Viral Diversity in Mixed Tree Fruit Production Systems Determined through Bee-Mediated Pollen Collection

Commercially cultivated Prunus species are commonly grown in adjacent or mixed orchards and can be infected with unique or commonly shared viruses. Apple (Malus domestica), another member of the Rosacea and distantly related to Prunus, can share the same growing regions and common pathogens. Pollen can be a major route for virus transmission, and analysis of the pollen virome in tree fruit orchards can provide insights into these virus pathogen complexes from mixed production sites. Commercial honey bee (Apis mellifera) pollination is essential for improved fruit sets and yields in tree fruit production systems. To better understand the pollen-associated virome in tree fruits, metagenomics-based detection of plant viruses was employed on bee and pollen samples collected at four time points during the peak bloom period of apricot, cherry, peach, and apple trees at one orchard site. Twenty-one unique viruses were detected in samples collected during tree fruit blooms, including prune dwarf virus (PDV) and prunus necrotic ringspot virus (PNRSV) (Genus Ilarvirus, family Bromoviridae), Secoviridae family members tomato necrotic ringspot virus (genus Nepovirus), tobacco necrotic ringspot virus (genus Nepovirus), prunus virus F (genus Fabavirus), and Betaflexiviridae family member cherry virus A (CVA; genus Capillovirus). Viruses were also identified in composite leaf and flower samples to compare the pollen virome with the virome associated with vegetative tissues. At all four time points, a greater diversity of viruses was detected in the bee and pollen samples. Finally, the nucleotide sequence diversity of the coat protein regions of CVA, PDV, and PNRSV was profiled from this site, demonstrating a wide range of sequence diversity in pollen samples from this site. These results demonstrate the benefits of area-wide monitoring through bee pollination activities and provide new insights into the diversity of viruses in tree fruit pollination ecosystems.

Productivity and amarketable gualities of apple tree fruits of the Golden Delicious variety on low growing rootstocks depending on pruning

One of the main agrotechnical activities carried out in the garden is tree pruning. When studying the variety-double combinations of apple trees in certain environmental conditions, it is necessary to take into account the strength of growth, the density of fouling, the type of branching, the structure of fruit formations, which depends on the varietal characteristics and technologies of growing plantations.The author presents the results of studying the parameters of the influence of the degree of pruning of Golden Delicious apple trees grafted on low-growing rootstocks SK-7 and M-9, depending on the rootstock, on growth processes, productivity and marketable qualities of apple fruits. The reaction of plantings to pruning was determined depending on the biological characteristics of the variety and on the degree of branch removal and their orientation. With an increase in the intensity of pruning, the leaf surface area per fruit on the rootstock SK-7 was 180–750 cm², on the rootstock M-9 — 172–619 cm², respectively. The yield of apple trees from one tree on the rootstock SK-7 was 13.2 kg with a minimum shape, 11.4 kg with an average, 10.5 kg with a maximum, and 11.4 kg, 9.5 kg and 7.7 kg on the rootstock M-9, respectively. The average weight of fruits grafted on the rootstock SK-7 increased by 1.9 times, and on the rootstock M-9 — by 1.3 times.It was noted that the life cycles of trees on the low-growing dwarf rootstock SK-7 were 10–12% higher than on the rootstock M-9.

Enhancing Olive Cultivation Resilience: Sustainable Long-Term and Short-Term Adaptation Strategies to Alleviate Climate Change Impacts

Olive cultivation, an icon of Mediterranean agriculture, economy, and cultural heritage, faces significant challenges due to climate change and soil degradation. Climate projections indicate that altered precipitation patterns, rising temperatures, and increased frequency of extreme weather events will adversely affect olive tree growth, fruit quality, and yield. This review provides a novel perspective on addressing these challenges through both long-term and short-term adaptation strategies, emphasizing innovative products, advanced technologies, and practical solutions that must work synergistically and be tailored to regional conditions. Long-term practices refer to proactive strategies for enduring climate resilience, including cover cropping, mulching, soil amendments, and breeding programs which enhance soil health, improve water retention, and increase the trees’ resilience. Short-term strategies focus on immediate impacts, offering immediate stress relief and enhanced plant physiological responses, including optimized irrigation systems, pruning management, particle coating films, biostimulants, and plant growth regulators. The review underscores the importance of aligning agricultural practices with sustainability goals and evolving environmental policies and the education of farmers and policymakers. By integrating adaptive practices and technological advancements, the olive sector can better address climate challenges, contribute to global food security, and advance environmental sustainability.

Fulvic and Salicylic Acids Improve Morpho-Physio-Biochemical Attributes, Yield and Fruit Quality of Two Mango Cultivars Exposed to Dual Salinity and Heat Stress Conditions

Abstract Purpose The present research’s main objective was to explore the potential stimulative effect of fulvic acid (FA) as a soil conditioner and salicylic acid (SA) as foliar spraying on morpho-physio-biochemical attributes, fruit yield, and quality of ‘Sediek’ and ‘Ewais’ mango cultivars (cvs.) grown under saline calcareous soil and heat stress conditions Methods Eight treatments, namely, 200 (FA200) and 400 (FA400) g FA tree−1 as a soil addition, 200 (SA200) or 400 (SA400) mg SA L−1 as foliar spraying, and their bilateral combinations (e.g., FA200 + SA200, FA200 + SA400, FA400 + SA200, and FA400 + SA400) compared to untreated control on morpho-physio-biochemical attributes, yield, and fruit quality of ‘Sediek’ and ‘Ewais’ mango cvs. grown under saline calcareous soil and heat stress conditions were assessed. These treatments were carried out using a split-plot arrangement in a randomized complete block design replicated three times during the 2022 and 2023 seasons. Results Cultivar Sediek had higher SPAD value, leaf proline and phenolic content, leaf area, fruit weight, yield and vitamin C than Ewais which had higher tree water status and shoot length. Saline calcareous and heat-stressed mango trees without FA or/and SA treatment had a significant decline in their water status, photosynthetic traits, biochemical responses that adversely affected growth and yield and fruit quality. However, soil FA addition and foliar SA spraying alone or in combination at any application level attenuated the negative effects of saline calcareous and heat-stress conditions via enhancing the morpho-physio-biochemical attributes, positively reflecting in tree growth, yield, and fruit quality. FA treatment alone improved tree water status (membrane stability index; MSI and relative water content; RWC), photosynthetic traits (SPAD value and maximum photochemical efficiency; Fv/Fm), leaf area, fruit weight, fruit yield, and fruit vitamin C (fruit vit.C), while SA treatment alone enhanced leaf proline and phenolic content, shoot length, and fruit total soluble solids (fruit TSS) compared to the non-FA or SA-treated control. Moreover, co-application of FA400 and SA400 effectively alleviated the harmful impacts of dual stress of heat and salinity on mango trees by improving MSI, RWC, SPAD value, Fv/Fm, proline and phenolic content, fruit weight, fruit yield, fruit TSS, fruit vit.C by 19.7, 26.1, 46.7, 18.7, 101.7, 390.7, 42.7, 6.8, 22.6, 69.6% (averages of the two seasons), respectively, compared to the non-FA or SA-treated trees. Conclusion It is recommended to add 400 g FA tree−1 to soil integrated with 400 mg SA L−1 foliar spraying four times at 30-day intervals for improving water status and photosynthetic traits, proline and phenolic accumulation, thereby growth, yield, and fruit quality of mango trees exposed to dual stress of heat and salinity under arid conditions.

Biofunctionality of a new vinegar rich in anthocyanin from red-fleshed Niedzwetzky's apple: An ornamental plant.

In recent years, red-fleshed apple has attracted a lot of attention due to its pleasant appearance, taste, and being a valuable source of anthocyanins. Generally, different types of this apple are known as ornamental apple plants that are rarely found in various regions around the world like New Zealand, Kazakhstan, Kyrgyzstan, Australia,China, and Turkey. This study focused on the accumulation and changes of the bioactive and aroma-related volatile components at different production stages of a red-fleshed apple vinegar. The aim of this study is to produce an anthocyanin- and vitamin C-rich vinegar (NAV) from red-fleshed Niedzwetzky's apple for the first time. According to the results, in this vinegar, it wasdetermined high concentrations of total phenolic content (904.8mg-GAE/mL), total flavonoid content (0.25mg-EGCE/mL), vitamin C content (3024.3mg-AAE/mL), and 1,1-diphenyl-2-picrylhydrazyl (8.33mmol-TE/mL), as well as FRAP (13.57mmol-ISE/mL), respectively. Moreover, total anthocyanin content value was found to be 6.46mg/g. One of the components that provide the specified functional effect in this vinegar is chlorogenic acid, which constitutes the main phenolic compound, and the other one is cyanidin-3-glucoside, which is the major anthocyanin in this vinegar. The main volatile components associated with the aroma of vinegar are -acetic acid, -phenylacetic acid (5067.7µg/100mL), -phenethyl alcohol (3096.1µg/100mL), and -nonanoic acid (2939.0µg/100mL) compounds. Consequently, it is recommended to expand the range of Niedzwetzky's apples in the production and consumption of food products such as functional vinegar. Thus, a new vinegar with high functional properties will be introduced to the worldwide food industry. PRACTICAL APPLICATION: In this study, vinegar was produced from the small and dark-red-flesh-colored fruits of Niedzwetzky's apple tree, which is known in a small part of the world and is generally used as an ornamental plant due to its red-pink flowers. It has been determined that the produced vinegar has high bioavailability due to the apples with red inner flesh and high anthocyanin content and has a desirable aromatic content. Thus, a food product with high functional quality and desirable aroma, accessible to consumers all over the world, has been produced from a little-known fruit.

Future aridity and drought risk for traditional and super-intensive olive orchards in Portugal

Portugal, a leading olive oil producer, boasts six Protected Denomination of Origin (PDO) regions, with distinct olive orchard (OR) densities (traditional rainfed to super-intensive irrigated). This study aimed to assess future drought and aridity conditions and the impacts on ORs located in the PDOs. Therefore, drought and aridity indicators were considered for the historical (ERA5: 1981–2000) and future periods (2041–2060; 2081–2100), and anthropogenic forcing scenarios (RCP4.5 and RCP8.5), using a 7-member ensemble of global climate models. From Spearman’s correlation analysis, Annual Mean Aridity (AIA) was selected as the most representative indicator of the climate conditions, to which the ORs were exposed. Readily Available Soil Water (RAW; mm) was considered to represent the available soil water reservoir for olive trees. Moreover, the Olive Drought and Aridity Risk Index (ODAR) was developed to determine each OR's future risks. This index considered that the AIA and RAW were weighted by OR density fractions. In the future, southern Portugal will be more arid (0.69) than northern and central (0.60). ORs soil shows lower RAW in southern PDOs (< 60 mm) than in central and northern regions (> 90 mm). These results suggest that the south of ORs will be more exposed to water stress than the northern regions. According to ODAR, the ORs exposed to low and high risk will be mainly located in the central parts of the PDOs. In northern ORs, moderate to high risk will predominate. In the south, however, the risk will be very high, which means that the olive tree growth, fruit development, and olive oil quality could be negatively affected. Implementation of tailored adaptation measures will be required to improve the climate resiliency of the sector.

Heavy Metals in Tree Parts (Roots, Bark, Leaves) and Fruits Grown in Mechanic Workshops in Nigeria

The day-to-day activities carried out at the mechanic workshop like panel beating, welding, and automobile battery servicing may result in high amounts of heavy metals in the soil near mechanic workshops. Spent engine oils also emit a huge number of toxic metals, when disposed of on the floor at workshops, they settle on soil and are absorbed into nearby trees and plants. Therefore, making the tree parts and fruits at mechanic workshops prone to attack by heavy metals. This work is focused on testing if the presence of heavy metals would have adverse effects on the tree parts (roots, shoots, upper leaves, lower leaves) and fruits of mechanic workshops. A mechanic village in Abeokuta, Ogun State was chosen as the case study. The tree parts were oven-dried, ground, digested, and taken for analysis using AAS. Zinc (Zn), Lead (Pb), and Mercury (Hg) were found in higher amounts than the recommended allowable limits by WHO/FAO. Results show that the upper bark had the highest heavy metal concentration. In general, the tested heavy metals were recognized in the order: Zinc (Zn) &gt; Lead (Pb) &gt; Mercury (Hg) &gt; Nickel (Ni) &gt; Manganese (Mn) &gt; Iron (Fe) &gt; Copper (Cu). It is recommended that mechanic villages should be sited far from residential areas. Remediation of polluted soil should be encouraged. Phytoremediation was suggested to be the best method for reducing the concentration of heavy metal in the soils and tree parts at mechanic workshops. Continuous education and training should be provided for automobile repairers/ mechanics, emphasizing the environmental implications of their poor occupational waste management and the dangers of eating fruits and taking herbs from trees planted in workshops.

Dynamic Analysis of the Fruit Sugar-Acid Profile in a Fresh-Sweet Mutant and Wild Type in 'Shatangju' (Citrus reticulata cv.).

Citrate is a major determinant of fruit flavor quality. Currently, citrus species and/or varieties with significant alterations in citrate level have greatly advanced the molecular basis of citrate accumulation in fruit. However, in-depth dissections of the molecular mechanism specific to citrate accumulation are still limited due to the lack of mutants, especially within one single variety. In this study, a fresh-sweet 'Shatangju' mutant (Citrus reticulata cv.) was obtained during a survey of citrus resources in Guangdong, China, and the phenotype, fruit morphology, and primary flavor profiles were comparatively analyzed. Unlike the wild-type 'Shatangju' (WT), the mutant (MT) material exhibited a dwarfed and multi-branched tree shape, delayed flowering and fruit ripening at maturity, a prolonged fruit tree-retention time, and a decreased single fruit weight at maturity. Dynamic measurement of the metabolite levels further suggested that the contents and fluctuation patterns of vitamin C, malate, quinate, and oxalate showed no obvious difference between MT and MT fruits, while the citrate level in MT fruits significantly decreased over various developmental stages, ranging from 0.356 to 1.91 mg g-1 FW. In addition, the accumulation patterns of the major soluble sugars (sucrose, fructose, and glucose), as well as the sugar/acid ratio, were also altered in MT fruits during development. Taken together, this study provides a novel acid-free 'Shatangju' mutant, which can serve as a powerful tool for the research of fruit flavor quality, especially for the comprehensive understanding of the molecular mechanism of citrate accumulation in fruits.

Valorization of Date Fruit (Phoenix dactylifera L.) as a Potential Functional Food and Ingredient: Characterization of Fiber, Oligosaccharides, and Antioxidant Polyphenols.

The fruit of the date tree (Phoenix dactylifera L.) is increasingly recognized for its nutritional and functional value. This exotic fruit shows variable composition, influenced by factors such as variety, ripening stage, and climatic conditions. In this context, this study aimed to investigate the nutritional profile and the bioactive components, including phenolic compounds and oligosaccharides, in different varieties of dates from Saudi Arabia collected at the Tamr ripening stage. The HPLC-ESI-MS analysis identified a total of 15 phenolic compounds, principally phenolic acids and flavonoids. Among the varieties tested, Safawi exhibited the highest phenolic concentration (1132 µg/100 g dw). To the best of our knowledge, the oligosaccharide composition is described for the first time among different varieties, with Sukari showing the highest concentration (3.37 g/100 g dw). Moreover, the antioxidant capacity (DPPH, ABTS, and FRAP assays) was assessed following a solid-phase extraction (SPE) clean-up to remove interferents, especially sugars. These results provide valuable insights into the health-promoting properties of date fruit as a functional food and provide a foundation for further research into their industrial applications as functional ingredients.

UMBU TREE (Spondias tuberosa Arr. Cam. - Anacardiaceae): FROM EXTRACTIVE TO PLANTED CULTURE IN BRAZIL

Umbu tree (Spondias tuberosa Arr. Cam.) is botanical species native to the Caatinga that plays significant cultural and economic role in Northeast Brazil. The aims of this study to evaluate the trend in umbu fruit production over a period of 21 years and to discuss the cultivation of the species, associated with its socioeconomic and environmental advantages in the semiarid region of Northeast Brazil. Data on extractive production and the monetary value of umbu fruit were obtained from the official platform of the Brazilian Institute of Geography and Statistics. Silvicultural aspects cultivation, management, and its market was obtained from specialized literature. Descriptive statistics on the data set and a trend analysis through regression model fitting was carried out using JMP® software. A downward trend in umbu tree fruit was estimated for most states, except for Alagoas, Paraíba, and Rio Grande do Norte. Alagoas was the only one with the best average variation (74.6%) in production and price (US$ 0.83) per kg of production via extractivism. The cultivating through plantations for commercial fruit umbu production is an alternative to overcome the declining trend in extractivism, ensuring continuation of family income and environmental protection of umbu tree populations in their natural habitats.

Efficiency of Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) for controlling three plant-feeding mites on guava trees in Egypt

ABSTRACT Tegolophus guavae (Boczek), Brevipalpus phoenicis (Geijskes), and Tetranychus urticae Koch are plant-feeding mite pests that cause severe damage to the foliage and fruits of guava trees in Egypt. The phytoseiid mite, Neoseiulus californicus (McGregor), was released at three densities (100, 200, and 300 predators/tree). The results indicated that the efficiency of N. californicus was significantly influenced by the release rate. The highest mean reduction percentage after six months of release for T. guavae, B. phoenicis, and T. urticae was, respectively, at 300 predators/tree (64.90, 81.15, and 81.11%) in 2021 and (74.89, 83.76, and 83.07%) in 2022. The mean fruit yields (kg/treatment) in the released plots were substantially greater than those in the control (ranging from 8–16%). The current result suggests that releasing N. californicus is a viable option for biological guava mite pest management.

Comparing Apples and Oranges: Advances in Disease Resistance Breeding of Woody Perennial Fruit Crops.

Apple and citrus are perennial tree fruit crops that are vital for nutritional security and agricultural economy and to achieve the Sustainable Development Goals of the United Nations. Apple scab and fire blight, along with Huanglongbing, canker, and tristeza virus, stand out as their most notorious diseases and annually destabilize fruit supply. An environmentally sound approach to managing these diseases is improving tree resistance through breeding and biotechnology. Perennial fruit tree germplasm collections are distributed globally and offer untapped potential as sources of resistance. However, long juvenility, specific pollination and flowering habits, and extensive outcrossing hinder apple and citrus breeding. Advances in breeding approaches include trans- and cis-genesis, genome editing, and rapid-cycle breeding, which, in addition to conventional crossbreeding, can all facilitate accelerated integration of resistance into elite germplasm. In addition, the global pool of available sources of resistance can be characterized by the existing genetic mapping and gene expression studies for accurate discovery of associated loci, genes, and markers to efficiently include these sources in breeding efforts. We discuss and propose a multitude of approaches to overcome the challenges of breeding for resistance in woody perennials and outline a technical path to reduce the time required for the ultimate deployment of disease-resistant cultivars.

Sanitizer Resistance and Persistence of Listeria monocytogenes Isolates in Tree Fruit Packing Facilities

The foodborne pathogen Listeria monocytogenes can persist in produce processing environments, which increases the risk for food contamination. Increased resistance to antimicrobials commonly used in cleaning and sanitizing procedures may contribute to L. monocytogenes’ persistence in these environments. This study aimed to evaluate sanitizer resistance in L. monocytogenes isolates collected from three tree fruit packing facilities (F1, F2, and F3) during packing seasons 2020–2021 (Y1) and 2021–2022 (Y2), and to assess evidence of persistence based on the genomic similarity of isolates to historical isolates collected in previous years. L. monocytogenes isolates collected in 2020–2022 (n = 44) were tested for resistance to peroxyacetic acid (PAA) and a proprietary biofilm−removing agent using a broth microdilution assay. Further, L. monocytogenes isolates were whole genome sequenced and screened for the presence of antimicrobial resistance and virulence genes, as well as to assess the genomic similarity of isolates using the CFSAN SNP bioinformatic pipeline. Over half (57%) of the tested isolates had a PAA minimum inhibitory concentration (MIC) of 250 ppm, which was similar to the applied concentration of the PAA sanitizer in the three facilities (230 ppm). In contrast, 80% of tested isolates had a biofilm remover MIC of 0.13 ppm, which was substantially below the concentration applied in the facilities (137 ppm). Genomes of all tested isolates carried antimicrobial resistance (fosX, lin, mdrL, mprF, and norB) and virulence (inlA, inlB, plcA, plcB, prfA, hly, mpl, and iap) genes. L. monocytogenes isolates collected between 2020 and 2022 belonged to three distinct lineages, with 22 multilocus sequence types (MLSTs) belonging to 22 different clonal complexes. Genomic similarity analysis with historical isolates collected from the same facilities in 2016–2017 demonstrated a 5-year persistence of the genotypes ST 1003 and ST 554 in F2, which were no longer detected in 2022. Overall, our results highlight the need to re-evaluate sanitizer concentrations to effectively control persistent L. monocytogenes strains in tree fruit packing facilities.

A Novel Fusion Perception Algorithm of Tree Branch/Trunk and Apple for Harvesting Robot Based on Improved YOLOv8s

Aiming to accurately identify apple targets and achieve segmentation and the extraction of branch and trunk areas of apple trees, providing visual guidance for a picking robot to actively adjust its posture to avoid branch trunks for obstacle avoidance fruit picking, the spindle-shaped fruit trees, which are widely planted in standard modern apple orchards, were focused on, and an algorithm for apple tree fruit detection and branch segmentation for picking robots was proposed based on an improved YOLOv8s model design. Firstly, image data of spindle-shaped fruit trees in modern apple orchards were collected, and annotations of object detection and pixel-level segmentation were conducted on the data. Training set data were then augmented to improve the generalization performance of the apple detection and branch segmentation algorithm. Secondly, the original YOLOv8s network architecture’s design was improved by embedding the SE module visual attention mechanism after the C2f module of the YOLOv8s Backbone network architecture. Finally, the dynamic snake convolution module was embedded into the Neck structure of the YOLOv8s network architecture to better extract feature information of different apple targets and tree branches. The experimental results showed that the proposed improved algorithm can effectively recognize apple targets in images and segment tree branches and trunks. For apple recognition, the precision was 99.6%, the recall was 96.8%, and the mAP value was 98.3%. The mAP value for branch and trunk segmentation was 81.6%. The proposed improved YOLOv8s algorithm design was compared with the original YOLOv8s, YOLOv8n, and YOLOv5s algorithms for the recognition of apple targets and segmentation of tree branches and trunks on test set images. The experimental results showed that compared with the other three algorithms, the proposed algorithm increased the mAP for apple recognition by 1.5%, 2.3%, and 6%, respectively. The mAP for tree branch and trunk segmentation was increased by 3.7%, 15.4%, and 24.4%, respectively. The proposed detection and segmentation algorithm for apple tree fruits, branches, and trunks is of great significance for ensuring the success rate of robot harvesting, which can provide technical support for the development of an intelligent apple harvesting robot.