Orchards Research Articles

Multi-year evaluation of an attract-and-kill strategy for apple maggot fly (Diptera: Tephritidae) in New England commercial apple orchards.

Previously developed behavioral approaches for controlling the apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), include attract-and-kill (AK) systems such as perimeter trapping using either, odor-baited red sticky spheres or odor-baited, sticky-free attracticidal spheres with contoured tops that ensure the sustained release of both insecticide and feeding stimulant. Here, over a 3-year span in 26 commercial apple orchards across Massachusetts, New Hampshire, and Maine, we evaluated the effectiveness of a novel AK strategy for R. pomonella management. Synthetic apple blend lures were deployed on perimeter-row trees to attract the pest, while perimeter-row insecticide sprays blended with 2% sugar, a known phagostimulant, served as the lethal component. Comparatively, grower standard (GS) blocks received full-block insecticide sprays devoid of sugar and lures. Monitoring revealed that red sticky spheres in AK blocks captured significantly more R. pomonella adults than unbaited monitoring spheres in GS blocks. Penetration of R. pomonella into block interiors remained consistently low and statistically similar for both AK and GS blocks. Whole-block infestation levels showed no significant difference between the 2 management approaches. Notably, insecticide application in AK blocks was reduced by 75%, 64.7%, and 64.2% in 2019, 2020, and 2021, respectively, compared with GS blocks. This grower-friendly AK approach could be integral to a reduced insecticide spray-based strategy for apple cultivation in the northeastern United States.

Assessing native parasitoids of the invasive pest Drosophila suzukii (Diptera: Drosophilidae) in the Southeastern USA.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), commonly known as spotted-wing Drosophila (SWD), is an invasive insect pest threatening the economy of many small fruit farms in the Americas and Europe. Biological control using parasitoids is a promising strategy for improving the sustainable management of SWD. To use the parasitoids as biocontrol agents, recognizing and understanding the presence and preference of North American native parasitoids and their local adaptation is necessary. We conducted 2 season-long field explorations of North American native parasitoids of SWD during 2021 and 2022 at major blueberry-producing locations in southeast GA, USA. A total of 371 parasitoids of Drosophila were collected using fruit-baited sentinel traps and classified into 3 families: Figitidae, Pteromalidae, and Diapriidae. Leptopilina boulardi (Hymenoptera: Figitidae) and Pachycrepoideus vindemmiae (Hymenoptera: Pteromalidae) were the most abundant species. The abundance of parasitoids was higher during the peak blueberry ripening period through the end of the harvest season compared to all other phenological stages. Out of the North American native parasitoids of SWD that we collected, Pachycrepoideus vindemmiae successfully parasitized SWD in its natural habitat, and L. boulardi only parasitized SWD larvae at a low rate of 7% in the laboratory, but it failed to emerge from all the parasitized SWD. Ultimately, we found that the existing North American native parasitoids were inadequate to suppress the SWD in these locations. Planned intervention with the classical release of Asian native specialist parasitoids in addition to the existing SWD management approaches was deemed necessary in these areas.

Biological efficacy of selected insecticides for the control of the green apple aphid Aphis pomi (de Geer, 1773) on apple in Bulgaria

The aim of this study was to evaluate the biological efficacy of chemical insecticides, from different chemical classes, recommended for the control of the apple aphid Aphis pomi in apple orchards in Bulgaria. The experiment was carried out in 2023 in the experimental field of Agricultural University-Plovdiv. The insecticides tested were spirotetramat (Movento 100 SC), flonikamid (Teppeki) and acetamiprid (Mospilan 20 SG). The insecticides were applied at the concentrations recommended for the control of this and other pests. All the tested chemical insecticides showed very high biological efficacy, therefore they can be recommended as suitable for efficient control of Aphis pomi on apple. Keywords: Chemical insecticides, Movento, Teppeki, Mospilan, Aphis pomi, Аpple, Bulgaria

Susceptibility of apple varieties to infestation by aphids (Hemiptera: Aphididae) in Southern Bulgaria

Aphids regularly infest apple orchards and are considered as one of the most damaging species, especially in humid conditions. In 2021-2023, the collection of different species and the rate of infestation by aphids on different apple varieties were studied in the region of Plovdiv, Bulgaria. Among the four aphid species identified in the apple orchard, Aphis spiraecola and Dysaphis plantaginea were predominant, followed by Aphis pomi and Dysaphis devecta. The rate of infestation varied significantly among the apple varieties. The Gala Resistant was the most infested by the aphids with a population coefficient (K) 302.5, followed by the Crimson Crisp – 124, the Pinova – 91, and the Red del Mestar – 52.5. The least infested variety was the Super Chief – 0.9, followed by the Modi – 2.2, the Fujion – 2.8, the Enterprise – 7.2 and the Rosella – 19. Keywords: apples, varietal susceptibility, aphids

The Ecotoxicity of Pesticides Used in Conventional Apple and Grapevine Production in Austria Is Much Higher for Honeybees, Birds and Earthworms than Nature-Based Substances Used in Organic Production

It is debated whether the ecotoxicity of active substances (ASs) contained in synthetic pesticides applied in conventional agriculture (conASs) differs from nature-based ASs used in organic agriculture (orgASs). Using the official pesticide use statistics, we evaluated the ecotoxicity of ASs used in apple and grapevine production in Austria. In 2022, 49 conASs and 21 orgASs were authorized for apple production and 60 conASs and 23 orgASs were authorized for grapevine production in Austria. Based on the latest publicly available data on the actual use of pesticides in apple and grapevine production (from the year 2017), we evaluated their ecotoxicity based on information in the freely accessible Pesticide Properties and Bio-Pesticides Databases. The results showed that although the amount of ASs applied per hectare of field was higher in organic farming, the intrinsic toxicities of ASs used in conventional farming were much higher. The number of lethal toxic doses (LD50) of ASs applied in conventional apple orchards was 645%, 15%, and 6011% higher for honeybees, birds, and earthworms, respectively, than in organic apple production. In conventional vineyards, lethal doses for honeybees, birds, and earthworms were 300%, 129%, and 299% higher than in organic vineyards. We conclude that promoting organic farming would therefore contribute to the better protection of biodiversity on agricultural land and beyond.

Efficacy of Plant Tissue Culture Techniques for Eliminating Black Mulberry Idaeovirus (BMIV) from Infected Black Mulberry (Morus nigra)

Obtaining virus-free plants is a crucial step in disease management that enables reliable and profitable fruit farming. The present study applied various in vitro virus elimination protocols, including apical shoot culture, chemotherapy, thermotherapy, cryotherapy, and their combination, to eliminate black mulberry Idaeovirus (BMIV) from sour black mulberry. First, a shoot tip (0.5–2 mm) culture protocol was optimized, and four ribavirin concentrations (0, 10, 20, and 30 mg/L) were investigated over five weeks as a form of chemotherapy (ch). For the first thermotherapy treatment (Ch + Th1st), chemotherapy treatment was followed by a gradual increase in the temperature (24–33 °C). In another experiment (Th2nd + Ch), in vitro shoots were incubated in the dark for two weeks at two different temperatures (35 ± 1 °C and 37 ± 1 °C, for one week each). Subsequently, the shoot tips were incubated with various ribavirin doses. Finally, cryotherapy (Cr) was used with or without immersing the shoot tips in liquid nitrogen. A two-step RT-PCR was performed to assess the presence of the virus in 7–8-week-old in vitro plants. Th2nd + Ch significantly increased the shoot tip burst and plant survival/morphogenesis compared to the other treatments. Except for the application of cryotherapy, the protocols eliminated BMIV in different proportions, and the highest virus elimination rate (50%) was obtained by applying 30 mg/L ribavirin during the Ch + Th1st treatment. These findings are essential in preventing the dissemination of the virus and enabling the safe movement of germplasm around the world.

Identifying optimal ground feature classification and assessing leaf nitrogen status based on UAV multispectral images in an apple orchard

Identifying optimal ground feature classification and assessing leaf nitrogen status based on UAV multispectral images in an apple orchard

Socio-Economic Impacts of Fruit Crop Production in the Mungo Corridor, Littoral Region, Cameroon

Purpose: Agriculture, particularly fruit crop production, serves as a vital driver of economic growth worldwide. In Cameroon, the Mungo Corridor plays a substantial role in the agricultural sector, particularly in fruit crop production. This study aims to assess the socio-economic impacts of fruit crop production within the Mungo Corridor, a region known for cultivating bananas, pineapples, and mangoes. By evaluating the economic contributions and challenges, the study seeks to provide insights for policies that could enhance the sustainability and development of fruit production in the area. The study adopted a multi-stage sampling technique to select respondents and resource persons. Materials and Methods: Data collection involved the use of structured and pre-tested questionnaires along with an interview guide. Quantitative data was analyzed using the Statistical Package for Social Sciences (SPSS) version 16.0 and Microsoft Excel, while qualitative data from interviews was subjected to thematic analysis. Six subdivisions from the Mungo Division were purposely chosen to represent the agricultural activities within the region. Findings: The study confirms that fruit crop production has significant socio-economic benefits in the Mungo Corridor. Over a 10-year period, banana production reached 195,000 tons, while pineapple production rose from 6,543 tons in 2012 to 28,141 tons in 2022. Papaya production increased from 36 tons to 86 tons during the same period. The income from fruit sales enabled stakeholders to develop socio-economic activities, fostering regional development. Fruit crop production contributed to the construction of 12 schools (primary and secondary), 21 health centers, the rehabilitation of 8 fruit markets, 3 bus stations, and growth in the informal sector. However, the study also identified several challenges with Farmers face limited access to markets. Poor infrastructure affects production and distribution. The looming threat of climate change presents long-term risks to fruit farming. Implications to Theory, Practice and Policy: To address the challenges and ensure sustainable fruit crop production in the Mungo Corridor, the study recommends the implementation of policies that promote local products and support farmers through market access initiatives. Invest in transport, storage, and market infrastructure to improve efficiency. Develop interventions to mitigate the impact of climate change on fruit production and strengthen cooperation among farmers, government, and private actors to maximize the benefits of fruit crop production and foster sustainable development. By highlighting the essential role of fruit farming in the socio-economic development of the Mungo Corridor, the study emphasizes the need for renewed efforts to support the sector and enhance its contributions to regional growth.

The assessment of environmental effect and economic benefit for apple orchard under different stand ages in the Loess Plateau, China

The assessment of environmental effect and economic benefit for apple orchard under different stand ages in the Loess Plateau, China

A systematic analysis of scan matching techniques for localization in dense orchards

In recent years, different methods have been studied to determine machinery position within a grove, as an alternative for complementing GNSS (global navigation satellite system) information in cases where GNSS signal is occluded. Such a situation can be observed when agricultural machinery travels under dense foliage or on the slopes of mountains. Scan matching techniques arise as a possible solution for localizing the machinery, complementing the absence of the GNSS signal when necessary. However, since key points are difficult to obtain in heterogeneous, unstructured and non-rigid environments (such as orchard plants), the performance of scan matching techniques often decreases in agricultural environments. This paper suggests dividing the point clouds into horizontal and vertical segments to improve the performance of scan-matching methods in orchards. It also examines the best way for registered frames to overlap. We validate the analysis with extensive experimentation in a Fuji apple orchard. The results show that the cumulative localization error in scan matching techniques can be notoriously decreased with selective parts of the orchard, by up to 60%. The experimentation performed herein suggests that the proposed methodology can complement the GNSS navigation in a middle-long path.

Efficiency of agromeliorative practices for restoring soil fertility in irrigated apple orchards

Efficiency of agromeliorative practices for restoring soil fertility in irrigated apple orchards

Increasing Productivity and Fruit Quality of ‘Mutsu’ Apple Orchard by Dwarfing Treatments

The aim of this 2022 study was to evaluate the effect of tree growth-limiting treatments on the tree yield and quality of ‘Mutsu’ apples. The experiment was established on 7-year-old trees on M.9 rootstock in a commercial orchard in Wilga near Warsaw. Growth-limiting treatments included unilateral root pruning, spraying the trees with Regalis Plus 10 WG at various times, and spraying with Flordimex 480 SL. Eight combinations were used, with four replicates of 20 trees per repetition. The measurements included fruit set, length of this year’s shoots, yield per tree, average fruit weight, and the size structure of the yield. The distinctive physiological status of the apples was assessed directly after harvest, directly after 8 months of storage under CA conditions (1.5% CO2, 1.5% O2, 1 °C, >92% RH) and after an additional 7 days of shelf-life. Spraying trees with Regalis Plus 10 WG from the balloon stage onwards, irrespective of the treatment with root pruning, was most effective in both inhibiting long-stem growth and increasing tree yield (by almost two times) by increasing the number of apples per tree. The growth response of long-stemmed apple trees to both unilateral root pruning and Ethephon spray was significantly lower than it was to Regalis Plus 10 WG spray and had relatively little effect on their yield. Regalis Plus 10 WG resulted in a clear reduction in average fruit weight (by about 100 g), which, in the case of the large-fruited cultivar ‘Mutsu’, should be seen as an advantage. Its application from the balloon stage onwards promoted higher apple firmness at harvest and after simulated handling preceded by long-term storage.

Genome sequence of a European Diplocarpon coronariae strain and in silico structure of the mating-type locus

Diplocarpon coronariae is a fungal pathogen that is prevalent in low-input apple production. Over the past 15 years, it has become increasingly distributed in Europe. However, comprehensive insights into its biology and pathogenicity remain limited. One particular aspect is the rarity of the sexual morph of this pathogen, a phenomenon hitherto unobserved in Europe. Diplocarpon coronariae reproduces through a heterothallic mating system requiring at least two different mating types for sexual reproduction. Genes determining the mating types are located on the mating-type locus. In this study, D. coronariae strain DC1_JKI from Dresden, Germany, was sequenced and used to unravel the structure of the mating type locus. Using short-read and long-read sequencing methods, the first gapless and near-complete telomere-to-telomere genome assembly of D. coronariae was achieved. The assembled genome spans 51.2 Mbp and comprises 21 chromosome-scale contigs of high completeness. The generated genome sequence was used to in silico elucidate the structure of the mating-type locus, identified as MAT1-2. Furthermore, an examination of MAT1-1 and MAT1-2 frequency across a diverse set of samples sourced from Europe and Asia revealed the exclusive presence of MAT1-2 in European samples, whereas both MAT loci were present in Asian counterparts. Our findings suggest an explanation for the absence of the sexual morph, potentially linked to the absence of the second mating idiomorph of D. coronariae in European apple orchards.

A classification and recognition model for multiple fruit tree leaf diseases

Abstract Fruit tree leaf diseases affect both fruit survival rate and orchard revenue. Rapid and accurate identification of tree leaf diseases not only prevents the spread of diseases but also ensures healthy tree growth and improves fruit quality. Existing models mostly focus on individual types of tree leaf diseases, with limited applications in the identification of multiple tree leaf diseases. In response to the insensitivity of current classification models to disease region features and the issue of increased error rates due to the presence of similar diseases, this study proposes a residual network model based on the ECA channel attention mechanism and meta-Acon adaptive activation function.The model employs ResNet34 as the backbone network and incorporates the ECA module after each residual block to focus on relevant information. Additionally, a new activation function called meta-Acon is introduced to enhance the model's generalization ability through its dynamic learning capability. Finally, the model's recognition performance is improved by fusing bottom-level features with features from other layers using the Feature Pyramid Network (FPN).Experimental results on a dataset augmented with Mosaic processing show that the FPEM-ResNet34 model achieves a classification accuracy of 98.46%. Compared to other common models such as VGG-16, Inception-V1,AlexNet, and ResNet50, the proposed method mentioned in this paper demonstrates more effective improvement in the accuracy of tree leaf classification, making it highly valuable for practical applications..

Tetranychus urticae Koch Biology on Apple Trees

The two-spotted spider mite (Tetranychus urticae Koch) is a polyphagous arthropod herbivore that consumes over 1,100 plant species from 140 distinct plant families, including those producing harmful chemicals in temperate and tropical climates. It is an important pest in greenhouse and field cultivation, causing damage to various crops such as citrus, apples, grapes, tomatoes, peppers, cucumbers, strawberries, maize, and soy. T. urticae ability to spread over agricultural fields and adapt to environmental stressors is linked to its high propensity for mutation, leading to the highest frequency of pesticide resistance among arthropods. The genetic diversity of T. urticae gathered from apple orchards throughout Poland has been studied to investigate potential correlations between molecular variations and the occurrence of resistance to METI-acaricides. Research has shown that an abundance of leaf pubescence on the abaxial leaf surface adversely affects the development of European red mite, two-spotted spider mite, and carmine spider mite. However, due to variations in leaf sizes, tree canopy, tree ages, and the existence of natural enemies, it is impossible to compare data gathered due to variations in leaf sizes, tree canopy, tree ages, and the presence of natural enemies. Pesticide treatments negatively impact fruit plantations' ecosystems, devastating biodiversity, altering the makeup and structure of arthropod populations, and promoting mass reproduction of phytophage mites by displacing certain species with others. The most extensive research has been done on the common spider mite's development of resistance to avermectin group preparations, with some studies showing resistance to multiple acaricides.

Investigation of resistance ratios and resistance mechanisms of Cydia pomonella (L.) (lepidoptera: Tortricidae) populations collected from apple orchards in Isparta (Türkiye) against some insecticides

The codling moth, Cydia pomonella is an important pest that causes significant economic losses in apples and walnuts in the world. The aim of this study was to investigate, for the first time in Türkiye, the resistance status and resistance mechanisms of codling moth, Cydia pomonella against indoxacarb, deltamethrin and emamectin benzoate. All apple orchard populations developed resistance ratios ranging from 3.38 to 22.37-fold to deltamethrin, 5.67–29.87-fold to indoxacarb and 1.46–3.05-fold to emamectin benzoate. The interaction of some synergists triphenyl phosphate (TPP), piperonyl butoxide (PBO) and diethyl maleate (DEM) with indoxacarb and deltamethrin was analyzed in the susceptible, MAREM and Tepeli populations with moderate resistance to indoxacarb and deltamethrin. While indoxacarb + TPP showed a significant synergistic effect only in MAREM population, a significant synergistic effect was observed with indoxacarb + TPP and indoxacarb + PBO in Tepeli population. The activities of detoxifying enzymes [esterase, glutathion –S– transferase (GST) and cytochrome P450 monooxygenase (P450)] studied by biochemical methods showed some variation depending on the population. The results of biochemical analyses showed that esterase and GST enzyme activities of all populations was between 0.51 and 0.94, 0.77 and1.29 mOD min−1mg−1 proteins, respectively. The P450 enzyme activities ranged from 0.53 to 0.78, RFU min−1mg−1 proteins. In addition, the L1014F knockdown mutation (CTT to TTT) corresponding to leucine to phenylalanine amino acid substitution of the voltage-gated sodium channel in Cydia pomonella was determined in MAREM and Tepeli populations. It was determined that while MAREM and Tepeli populations developed moderate resistance, the other populations developed a low level resistance to deltamethrin and indoxacarb. On the other hand, all populations developed a low level resistance to emamectin benzoate. The P450 and esterase enzyme activities were significantly higher in MAREM and Tepeli populations which were resistant to deltamethrin and indoxacarb than the susceptible population. In addition, a Kdr point mutation L1014F was detected in the deltamethrin resistant MAREM and Tepeli populations.

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.

Genome sequence resources from three isolates of the apple canker pathogen Neonectria ditissima infecting forest trees

Neonectria ditissima is a generalist ascomycete plant pathogen causing canker diseases on a variety of hardwood tree species and can cross-infect many of them. The fungus enters the plants through wounds throughout the year. N. ditissima is considered a major threat to apple production responsible for the fruit tree canker disease which damages trees and causes rotting of fruits in storage. Nearby forests and shelter belts can serve as source of inoculum for well-managed apple orchards. Thus, knowledge about the N. ditissima isolates infecting different host species is essential for designing integrated pest management strategies. Here, we describe the genomes of three N. ditissima isolates, Nd_iso34, Nd_iso35, and Nd_iso36, infecting European beech, American tulip tree, and American beech, respectively. We obtained genome assemblies of ca. 45 megabases for all isolates, covering 94% of the N. ditissima reference annotation, and 97% of the universal single-copy orthologs (BUSCOs). We conclude that these genome assemblies are a highly relevant resource considering the scarcity of genomic data available for N. ditissima.

A Capability Indicator for Family Farms in the Global North – Concept and Test from Switzerland

ABSTRACT Amartya Sen’s capability approach suggests assessing people’s well-being by examining whether they are able to do and be what they value, instead of merely looking at their income. People’s well-being is the basic theme of social sustainability. This study intends to operationalise social sustainability by developing a capability indicator for family farms in the Global North. Therefore, this study develops a conceptual approach that was tested through a sample of 555 Swiss fruit and vegetable farm managers. The managers were asked four questions on consumption options and six questions on decision making on their farms, and answers were aggregated in two different ways: first, simply by summing up the response values, and second, by weighting the response values based on their regressors to explain the probability of the farm being taken over. The data were analysed descriptively regarding correlations between the questions and by an ordered logit analysis. The results indicated that both the simple and the weighed capability indicators were good predictors of the perception of whether the farm would be taken over by the next generation and thus of an aspect of social sustainability. This implies that, for example, policy measures to reduce the environmental impacts of farming have a negative side effect that may have been underestimated so far, as they reduce the capability of the farm managers. The capability of farmers at both production and consumption levels is relevant to their well-being.

Impact of Aggregation Pheromone Traps on Spatial Distribution of Halyomorpha halys Damage in Apple Orchards.

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is an invasive pest causing significant damage to tree crops. Our study examined the impact of newly designed aggregation pheromone-baited 'mini-sailboat' (MSB) traps for controlling H. halys and its effect on the spatial distribution of fruit damage. Four replicates of four traps, with a total of 16 MSB traps, were placed along a 1.3 km border of apple orchards, concentrating the traps on one side of the orchards. A fruit damage assessment for incidence and severity was conducted at increasing distances from the orchard border where the traps were placed, encompassing 107 assessment points. Our study showed that deploying MSB traps along the orchard border significantly increased fruit damage within the first 45 m compared to control plots without traps. However, beyond the first 45 m from the border, there was a significant reduction in damage incidence. In the treated plots, 50% of the damage occurred within 26 m of the traps, while in control plots, within 85 m. Shifting the fruit damage pattern means restricting the pests lingering in a narrow strip near the MSB traps, which paves the way for improved techniques to restructure the crop perimeter.