Peach Orchards Research Articles

Diversity of aphids and their natural enemies on peach orchards, Prunus persica (L.) Batsch, in Lakhdaria at Bouira (Algeria)

Diversity of aphids and their natural enemies on peach orchards, Prunus persica (L.) Batsch, in Lakhdaria at Bouira (Algeria)

Diversity of aphids and their natural enemies on peach orchards (Prunus persica L. Batsch) in Lakhdaria at Bouira (Algeria)

Diversity of aphids and their natural enemies on peach orchards (Prunus persica L. Batsch) in Lakhdaria at Bouira (Algeria)

Inoculation of Arbuscular Mycorrhizal Fungi Isolated from Peach Orchards and Vineyards in Aldrighi Peach Rootstock Plants

Arbuscular mycorrhizal fungi species (AMFs) present intraspecific differences in the ability to stimulate plant growth and depend on genetic and environmental factors involved among the biotic agents. This work aimed to evaluate the influence of the AMFs Glomus clarum and G. etunicatum isolated from peach orchards and vineyard on the vegetative growth, content of nutrients and carbohidrate contents on Aldrighi peach rootstocks plants. The experiment was conducted in a greenhouse, with a split-plot experiment, with 15 plants per plots and four repetitions. The plants inoculated with AMFs had higher responses in height, diameter, leaf area, fresh and dry biomass of shoots and content of reserves, due to the increased absorption of nitrogen, phosphorus and potassium in excess of non-inoculated plants. Data were submitted to analysis of variance using the Statistical Analysis System (SAS) program and the means were compared using Duncan's test at a 5% significance level. Simple correlation analyzes were performed using Pearson's correlation coefficient (r) with maximum values represented by r = 1 and r = -1. All AMF isolates benefited the Aldrighi peach rootstock plants, accelerating vegetative development and increasing macronutrient content. The study showed a correlation between root colonization and the increase in plant development parameters. The symbiosis efficiency was higher with isolates from peach orchards, when compared with isolates from grapevine orchards.

Characterization of the microbial community response to replant diseases in peach orchards

This study attempted to monitor the development of microbial communities and reveal the correlation between the soil microbial community and soil nutrient factors over different years following the replanting of peach trees. The replanted soil (RS) and nonreplanted soil (NRS) were collected from peach orchards with different growth years (1, 3, 5, 7, 9, 11, and 13 years) in the same region. The soil bacterial and fungal community diversities were analyzed by high-throughput sequencing technology. Redundancy analysis (RDA) was used to show the correlation between the soil microbial community and environmental variables. The alpha diversities of the bacterial and fungal communities indicated that RS contained a higher abundance of bacterial and fungal operational taxonomic units (OTUs) than NRS. NMDS and ANOSIM analyses showed that the soil bacterial and fungal communities were significantly (P<0.01) affected by planting years, and that the main changes occurred in the first and ninth planting years. The presence of the bacterial orders Sphingobacteriales, Burkholderiales and Actinomycetales changed significantly after replanting. Some bacteria associated with bioremediation, such as Burkholderiales and Intrasporangiaceae, and some harmful pathogens, such as Penicillium and Ophiostomatales, significantly increased after replanting (LDA score>3.0). In addition, the soil nutrient contents were lower in RS than in NRS in the early stage (1–5 years), and the RDA showed that bacterial and fungal phyla are closely associated with environmental variables, including the potential of hydrogen (pH), ammonium nitrogen (AN), available phosphorus (AP) and available potassium (AK). These results lead to a deeper understanding of the microbial responses to replanting in peach orchards.

The importance of incorporating soil in the life cycle assessment procedure to improve the sustainability of agricultural management

The formidable ability of soil to store carbon has attracted an increasing number of studies, but few of them included soil organic carbon (SOC) sequestration as part of a carbon balance assessment in the agroecosystem. This raises some interesting questions: 1) how orchards conversion increase soil capacity to mitigate the green–house gases (GHG) emissions by storing C? 2) can it be considered in life cycle assessment (LCA)? 3) can SOC pools and soil biochemical properties determination improve LCA interpretation? To answer these questions, this study selected a ten– and fifteen–years–old peach orchards, a twenty–years–old pear orchard, a thirty–years–old kiwi orchard in south-east part of Emilia–Romagna Region (Italy), and a cereals’ field as reference. Soil samples were collected from 0 to 15 and 15–30 cm depths, and the SOC pool amounts (i.e., labile and recalcitrant) determined. LCA was used to estimate the GHG emissions (CO2eq) from the orchards. Results showed that the conversion from cereals to orchard production increased OC stock (+82 % on average) suggesting that orchards cultivation systems have the capacity to enrich soil organic matter. Fertilization had the greatest impact on CO2eq emission accounting for at least 40 % of total CO2eq emissions. Kiwi cultivation had the highest impact on GHG emissions mainly due to the high water and nutrient demand (0.045 and 0.149 kg CO2eq kg−1 fruit yr−1, respectively). When taking into account the C–CO2eq loss by fruit cultivation and C storage in soils, results would indicate that peach and pear orchard agroecosystems promote C sequestration. Conversely, kiwi cultivation showed large CO2eq emissions only partly counterbalanced by SOC sequestration. This study highlights the importance of including soils in LCA: if made mandatory this would allow a wider, yet more detailed, picture of the impact of agricultural practices on C budget. This simple step could help optimise resource management and at the same time improve agroecosystem sustainability.

Emissions of Greenhouse Gases and NO from Rice Fields and a Peach Orchard as Affected by N Input and Land-Use Conversion

Nitrogen (N) inputs and land-use conversion are management practices that affect soil greenhouse gas (GHG) and nitric oxide (NO) emissions. Here, we measured soil methane (CH4), nitrous oxide (N2O), and NO fluxes from rice fields and a peach orchard that converted from paddies to assess the impacts of nitrogen (N) inputs and land-use conversion on their emissions. Treatments included four paddy field treatments (PN0, PN160, PN220, and PN280) and one peach orchard treatment (ON280) with number indicating the N-input rate of kg N ha−1. The results showed that cumulative emissions of CH4, N2O and NO ranged from 28.6 to 85.3 kg C ha−1, 0.5 to 4.0 kg N ha−1 and 0.2 to 0.3 kg N ha−1 during the rice-growing season, respectively. In terms of greenhouse gas intensity, the PN280 treatment is the recommended N application rate. Land-use conversion significantly reduced the global warming potential from croplands. The conversion shifted soils from an essential source of CH4 to a small net sink. In addition, N2O emissions from the rice–wheat rotation system were 1.8 times higher than from the orchard, mainly due to the difference in the N application rate. In summary, to reduce agriculture-induced GHG emissions, future research needs to focus on the effects of N inputs on rice-upland crop rotation systems.

Temperate fruit farming in fragile lands of the Northwestern Himalayan region: Implications for subsoil nutrient availability, nutrient stock and soil quality

AbstractIn recent years, soil fertility in the Northwestern Himalayan (NWH) region has deteriorated partly due to accelerated soil erosion but mainly due to ineffective nutrient management for field crops. However, it is largely unknown whether long‐term temperate fruit farming has adverse effects on the soil fertility in NWH or not. Therefore, we conducted a study with the purpose of evaluating the impact of different land uses in the NWH ecosystem, namely: peach orchard (PO), apple orchard (AO), fertile‐fallow land (FL), and barren land (BL) on soil physico‐chemical characters, nutrient storage capacity, and soil quality index (SQI), along a soil‐depth gradient. A total of 116 composite soil samples [four treatments (i.e., land uses), 4‐ soil depths (0–0.2, 0.2–0.4, 0.4–0.6, and 0.6–0.8 m) and 5, 9, 9, and 6 replications for PO, AO, FL, and BL systems, respectively] were collected for laboratory analyses. Across depths, the soils under temperate fruit plantations had better soil physical conditions (i.e., lower bulk density and higher porosity) over FL and BL lands. The soils in this study can be categorized as slightly acidic to near neutral in soil reaction. Soils under temperate fruit plantations (PO and AO), averaged over depths, had significantly (p &lt; 0.05) less quantity of soil organic C, available nutrients (i.e., primary‐, secondary‐, and micro‐nutrients), nutrient storage capacity, and indices of soil quality, as compared to FL lands. These unfavourable effects were augmented in subsoils (0.2–0.8 m) than topsoils (0.0–0.2 m) affecting secondary‐ and micro‐nutrients more than primary‐nutrients. Results further revealed that these lands display a less favourable (i.e., very high) C:N ratio that could easily be degraded if brought under intensive farming. Restoration of depleted soil fertility in temperate fruit‐tree‐based ecosystems of NWH could be achieved through incentive‐based building‐up of soil organic matter and adoption of a soil‐test‐based nutrient management regime.

SOIL RESPIRATION UNDER DIFFERENT LAND USE SYSTEMS IN THE KUMAON REGION OF CENTRAL HIMALAYA, INDIA

Soil respiration (SR) is chiefly controlled by microclimatic conditions, microbial activity, and land use management practices of the particular ecosystem. In the present study, SR was measured under three different land-use systems viz. arable land (AL), a kitchen garden (KG), and peach orchard (PO) in the Almora and Nainital districts of Uttarakhand to observe the effect of soil temperature (ST) and soil moisture (SMC) on the rate of SR. The cumulative seasonal mean SR rate (g CO 2 m -2 h -1 ) was 2.67 ± 0.33, 4.3 ± 0.06, 8.29 ± 2.59 for the year 2017‒18, and 1.37 ± 0.28, 1.85 ± 0.05 and 2.27 ± 0.03 for the year 2018‒19 in AL, KG and PO respectively. The highest SR was found in PO followed by KG and AL. This study also found the spatial and temporal variations of SR in the selected land-use systems. The SR was positively correlated with SMC but negatively correlated with ST. Thus the ST explained the maximum variability of SR in the selected land-use systems. Overall, the results of this study clearly indicate that the microclimatic variables and land use management practices have a greater role in changes in SR of the studied region.

Net primary production and carbon budget in peach orchards under conventional and low input management systems

Fruit tree orchards are an important land-use type in the Mediterranean regions despite limited information on their potential role as carbon sinks to mitigate climate change and their capacity to store soil organic carbon (SOC). The objective of this study was to evaluate the ability of peach orchards (Prunus persica (L.) Batsch) to fix and accumulate carbon (C) in three contrasting management systems. The first system was representative of the current management recommended to French producers with high yield objectives (REF). The second system was managed with a Low-Input strategy (LI-1) for chemical pesticide application (−70%), nitrogen fertilization and water irrigation (~−25%). Lastly, the third system (LI-2) had the same low-input strategy but included a higher planting density (~2-fold) and a new tree shape training system. The experiment was conducted in the South of France for 7 years from planting (2013–2019). The aboveground biomass and C repartitions in various components of systems (tree organs and grass growing in alleys) were carried out by destructive measurements each year to determine Net Primary Production (NPP), Net Ecosystem Production (NEP) and Net Ecosystem Carbon Balance (NECB).The REF system had very high productivity during the mature tree period with 45.9 Mg ha-1 yr-1 of fresh fruit yield and 16.8 Mg ha-1 yr-1 of aboveground biomass, corresponding to 7379 kg C ha-1 yr-1 (738 g C m-2 yr-1). Orchard NPP (tree and grass) reached 11,003 ± 353 kg C ha-1 yr-1 (1100 ± 35 g C m-2 yr-1) and soil respiration was 3366 ± 776 kg C ha-1 yr-1 (337 ± 78 g C m-2 yr-1) leading to an NEP of 7637 ± 853 kg C ha-1 yr-1 (764 ± 85 g C m-2 yr-1) and an NECB of 4919 ± 858 kg C ha-1 yr-1 (492 ± 86 g C m-2 yr-1). Carbon accumulation was distributed 53% in perennial biomass, and the soil had an annual SOC stock change of 3.8‰. In the LI-system, the reduction of inputs and chemical pesticides did not impact the average NEP and NECB, even though pest infestations reduced biomass in 2015 and 2019. The same input reductions in the LI-2 system but with increased planting density provided significant increases in NPP (+10.5%) and NEP (+20.0%), leading to an NECB of 5876 ± 890 kg C ha-1 yr-1 (588 ± 89 g C m-2 yr-1), or 19.4% greater than the REF system during the mature tree period. This positive C accumulation was distributed 46% in the perennial biomass, which could reach 35.5 Mg C ha-1 (3550 g C m-2) after 15 years of orchard life. The SOC stock change was 10.0‰ in the LI-2 system, greater than the 4‰ initiative of the Paris COP21. Innovative peach orchards with agroecological management can mitigate environmental impacts by combining high-quality fruit production with enhanced CO2 sink capacity objectives.

Effects of Alternative Fertilization and Irrigation Practices on the Energy Use and Carbon Footprint of Canning Peach Orchards

Throughout peach orchards in Greece, plant protection, fertilization and irrigation are often conducted empirically, negatively affecting energy use efficiency and greenhouse gas emissions (GHG emissions). The aim of this study was to apply alternative fertilization and irrigation practices in canning peach orchards to improve nutrient and irrigation water management and to assess yield, energy input–output and the carbon footprint of the alternative cultivation practices for three important clingstone cultivars of different ripening periods. Energy use analysis revealed that the cultivation practice with the highest energy use was almost always irrigation, followed by fertilization, plant protection, weed control and pruning. Electricity, fuels, fertilizers and machinery presented the highest energy requirements. Alternative fertilization, in combination with deficit irrigation (DI), was more energy efficient compared to farmers’ practices in all cultivars based on energy use efficiency, energy productivity and specific energy. Irrigation was the cultivation practice with the highest impact on GHG emissions due to electricity and, secondly, to fuel consumption. Alternative fertilization and DI decreased the intensity (kg CO2eq kg−1) of the emitted GHG compared to farmers’ practices. In conclusion, alternative fertilization and irrigation practices improved energy use efficiency and decreased the carbon footprint of the canning peach orchards by improving yield and decreasing fertilizer and irrigation water input.

Evaluation and optimization of blends for attracting Trichogramma dendrolimi based on semiochemicals mediating tritrophic interactions in the orchard habitat

Trichogramma dendrolimi Matsumura (Hymenoptera: Trichogrammatidae) is one of the most important parasitic natural enemies of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) in peach and pear orchards. The artificial rearing T. dendrolimi have been widely used in biological control programs in recent years. However, its actual parasitic effect on the pest in the field is less, so it is important to develop attractants to increase the parasitic efficiency of the parasitoids. T. dendrolimi can be easily attracted by semiochemicals derived from flowers, intact plants, herbivore-attacked plants, and insects in its orchard habitats. In this paper, 73 semiochemicals were evaluated as potential attractants at three concentrations (0.1 mg/mL, 1 mg/mL, and 10 mg/mL) to T. dendrolimi by Y-tube olfactometer bioassays and Electroantennogram (EAG) technology, and then the mixtures of active individual compounds were further tested and evaluated in the field. As a result, 17 individual compounds showed attractive bioactivity to T. dendrolimi. Interestingly, when methyl salicylate and benzaldehyde mixed with linalool oxide or cis-3-hexenyl caproate in a volume ratio of 10:3:3 respectively showed excellent attractant bioactivity for T. dendrolimi in the orchard field. Thus, introducing such parasitoid attractants in orchard habitat may improve the biological control effect to pests.

Şeftali bahçesinde damla sulama yöntemi ile toprağa uygulanan yerel entomopatojen nematodların kalıcılığının belirlenmesi

The period of persistence of entomopathogenic nematodes (EPNs) in soil is an important factor in the success of biological control efforts. In this study, the persistency of four native Turkish entomopathogenic nematode species, Steinernema feltiae (Filipjev), S. carpocapsae (Weiser), S. affine (Bovien) and Heterorhabditis bacteriophora (Poinar), was investigated in a peach orchard after their application with a drip irrigation system in Çanakkale Province, Turkiye, in 2018 and 2019. The EPNs were applied at the rate of 50 IJs/cm2. After application, the persistency of the EPNs was determined with soil sampling on a monthly basis. EPN persistence in the soil was 90 days and 150 days in 2018 and 2019, respectively. Additionally, the persistency of the EPNs in soil after their application varied, depending on environmental factors. The longer survival of EPNs in soil after application is important for the increase of the efficiency of EPNs against pests. It was concluded that the local EPN species have potential for use in the biological control of agricultural pests.

The effectiveness of mass trapping of Ceratitis capitata (Wiedemann,1824) (Diptera: Tephritidae) in peach orchards in İzmir, Aydın and Mersin

Ceratitis capitata karantina zararlısı ve toleransı sıfır olarak kabul edilen bir türdür. Üreme kapasitesinin yüksek olması ve doğrudan meyvede zarar yapması nedeniyle zararlı ile mücadele yürütülmeden üretim yapmak mümkün olamamaktadır. Kimyasal mücadeleye alternatif olarak biyoteknik mücadele yöntemi olan kitle halinde tuzakla yakalama, zararlının çok yüksek olmayan popülasyonlarında başarılı sayılan bir mücadele şeklidir. Tuzaklar ile mücadelede farklı besin cezbedici materyaller kullanılarak bireylerin tuzağa çekilmesi sonucu öldürülmesi sağlanmaktadır. Bu çalışma, Ege ve Akdeniz Bölgelerinde şeftali bahçelerinde eş zamanlı yürütülmüş ve bölgeler arasındaki popülasyon farklılığına göre tuzakların etkinliğinin belirlenmesi amaçlanmıştır. Denemeler 2018 yılında Kuşadası (Aydın), Selçuk (İzmir) ve Erdemli (Mersin) ilçelerinde yürütülmüştür. Zararlının feromon tuzaklar ile popülasyon değişimi ve kitle halinde yakalama tuzaklarının etkinliği saptanmıştır. Mücadele tuzağı olarak Decis Trap (Bayer) isimli ürün kullanılarak tuzağın etkinlikleri saptanmıştır. Temmuz ayında Kuşadası, Selçuk ve Erdemli ilçelerinde sırasıyla 4.8, 149.1 ve 166.9 adet/tuzak ergin birey yakalamıştır. Buna göre Kuşadası ilçesinde %94.19, Selçuk ilçesinde %95.6 oranlarında etkili bir başarı sağlarken Erdemli ilçesinde %56.34 oranında etkili olmuştur. Akdeniz Bölgesi popülasyonunun Ege Bölgesine göre daha yüksek seyretmesi ve şeftali üretim sezonun daha uzun sürmesinden dolayı istenilen düzeyde başarı sağlanamadığı belirlenmiştir.

EFFECT OF ORGANIC BIOSTIMULANTS ON PRODUCTION AND QUALITY OF PEACH UNDER SAIS PLAIN CLIMATIC CONDITION

The improvement of crops quality and productivity, and the environment quality is an important problem worldwide. Due to the increased need for agricultural products and climate change, new tools has been developed that enhance plant tolerance against biotic and abiotic stresses .Therefore the use of plant biostimulants (formally known as bioeffectors), may be promising alternative to chemical methods, has become common practice in agriculture in stimulating growth .In this context our experiment was conducted in a conventional peach orchard in the Fez-Meknes region. Peach is an important cultivar in Morocco in general ; thanks to its good productivity with high-quality fruits.We chose peach for its place in the region's arboreal sector, its vulnerability to the effects of water stress and its growing demand in the market. The objective of our experiment is to study the effect of stimulants on the yield and quality of Peach (Prunus persica) in the face of biotic and abiotic stresses in the Sais Plain. The experiment was spread over two seasons on three-year-old trees. It consisted of the application of organic biostimulants (Vitazyme, Protifert LMW10, Protifert LMW6.3, Protifert Zinc and Naturfer), in order to study their effects on: fruit weight, fruit length, fruit diameter, flesh weight, core weight, Sugar content and titratable acidity. The analysis of the results via the SPSS (Statistical Package for the Social Sciences) software showed that the organic biostimulants studied have, in general, a positive effect on the improvement of the yield of the peach tree. This effect is particularly marked in the second year. Regarding the quality of peaches we found that the application of biostimulants increases the content of sugars in the fruit.

Chemical thinning of peach trees

Peach tree thinning is essential to harvest quality fruits and to keep balanced production for several years. Manual thinning of peach trees demands much work force and increases production costs. Chemical thinning may be an alternative solution, but efficiency depends on doses and species. This study aimed at evaluating the effect of metamitron – applied at different concentrations – on chemical thinning of peach trees in the south of Brazil. The experiment was carried out in a commercial peach tree orchard where ‘Sensação’ cultivars, in Morro Redondo, Rio Grande do Sul (RS) state, Brazil. The following metamitron concentrations were applied at concentrations of 100 mg L-1, 200 mg L-1, 300 mg L-1, 400 mg L-1, manual thinning was carried out 40 days after full bloom (DAFB) and to the treatment where the plants have no thinning. Fruit abscission, effective fructification, total number of plants per plant, production per plant, mean mass and fruit diameter were evaluated. Concentrations of 300 and 400 mg L-1 metamitron 40 DAFB provides promoted high fruit abscission, besides decreasing the number of fruits and production. Therefore, concentrations of 100 and 200 mg L-1 of metamitron 40 DAFB provides results in an efficient thinning practice similar to manual thinning for production, mass and fruit diameter.

The use of plant growth regulator Biosil in peach orchards in order to increase resistance to diseases in the humid subtropics of the Black Sea coast of the Caucasus

The article analyzes the results of using the plant growth regulator Biosil® to increase the resistance of peach to the main leaf diseases (peach leaf curl (caused by Taphrina deformans (Berk.) Tul.) and shot-hole disease (caused by Stigmina carpophila (Lév.) M.B. Ellis)). The studies were carried out for four years (2018-2021) in peach orchards in the zone of humid subtropics of the Black Sea coast of the Caucasus (Sochi, Russia). The degree of development of peach leaf curl in the control variant was 10.2-25.0%. The degree of development of shot-hole disease in the control variant was 9.2-29.8%. The use of Biosil in combination with fungicides in half doses and in pure form makes it possible to increase the resistance of the crop to the studied diseases. The maximum biological efficiency (up to 70%) in relation to leaf curl and up to 60% in relation to shot-hole disease was observed when Biosil was used in a tank mixture with fungicides. The use of the plant growth regulator Biosil makes it possible to reduce the dose of fungicides in peach agrocenoses while protecting against peach leaf curl and shot-hole disease by half. The use of the studied growth regulator for four years did not lead to a decrease in its biological efficiency.

Effects of adverse environmental factors on fruit set in a peach and apricot cultivar evaluation orchard

Effects of adverse environmental factors on fruit set in a peach and apricot cultivar evaluation orchard

A Fruit Colour Development Index (CDI) to Support Harvest Time Decisions in Peach and Nectarine Orchards

Fruit skin colour is one of the most important visual fruit quality parameters driving consumer preferences. Proximal sensors such as machine vision cameras can be used to detect skin colour in fruit visible in collected images, but their accuracy in variable orchard light conditions remains a practical challenge. This work aimed to derive a new fruit skin colour attribute—namely a Colour Development Index (CDI), ranging from 0 to 1, that intuitively increases as fruit becomes redder—to assess colour development in peach and nectarine fruit skin. CDI measurements were generated from high-resolution images collected on both east and west sides of the canopies of three peach and one nectarine cultivars using the commercial mobile platform Cartographer (Green Atlas). Fruit colour (RGB values) was extracted from the central pixels of detected fruit and converted into a CDI. The repeatability of CDI measurements under different light environments was tested by scanning orchards at different times of the day. The effects of cultivar and canopy side on CDI were also determined. CDI data was related to the index of absorbance difference (IAD)—an index of chlorophyll degradation that was correlated with ethylene emission—and its response to time from harvest was modelled. The CDI was only significantly altered when measurements were taken in the middle of the morning or in the middle of the afternoon, when the presence of the sun in the image caused significant alteration of the image brightness. The CDI was tightly related to IAD, and CDI values plateaued (0.833 ± 0.009) at IAD ≤ 1.20 (climacteric onset) in ‘Majestic Pearl’ nectarine, suggesting that CDI thresholds show potential to be used for harvest time decisions and to support logistics. In order to obtain comparable CDI datasets to study colour development or forecast harvest time, it is recommended to scan peach and nectarine orchards at night, in the early morning, solar noon, or late afternoon. This study found that the CDI can serve as a standardised and objective skin colour index for peaches and nectarines.

Degree-day risk thresholds for predicting the occurrence of Anarsia lineatella, Grapholita molesta and Adoxophyes orana in northern Greece peach orchards

In the present work, the phenology of the most important peach pests was studied to estimate the risk thresholds to be used in applying an updated automatic pest management decision support system. Particularly, the seasonal occurrence of Anarsia lineatella, Grapholita molesta and Adoxophyes orana was determined during 2018 and 2020 using pheromone traps from April till October in eight peach orchards in the prefecture of Pella in northern Greece. Additionally, the accumulated degree-days (DDs) were calculated for each moth and further related to the seasonal flight patterns to determine the period of which the activity of each species starts as well as the period of the moth population peak. Moth capture data of one more year, 2021, were used to validate the risk threshold predictions. In most cases, the risk threshold predictions were at acceptable levels and especially in forecasting the start and the peak of the first and second flight period of the above three species. The first captures of A. lineatella, G. molesta and A. orana, early in the season were observed at 70, 33 and 362 DDs, respectively (lower temperature thresholds: 11.4 °C, 9.5 °C and 7.2 °C, for A. lineatella, G. molesta and A. orana, respectively, and Biofix: 1&lt;sup&gt;st&lt;/sup&gt; of January in all the cases). The highest number of moth captures of A. lineatella, G. molesta and A. orana were observed at 150.6, 77.9 and 428.7 DDs, while the start of the subsequent second flight was observed at 365, 133 and 362 DDs, respectively. Moreover, the peak of the second moth flight was observed at 511.5, 204.8 and 1 239.5 DDs, for A. lineatella, G. molesta and A. orana, respectively. The current degree-day risk thresholds can be used for the precise timing of pesticides and are a prerequisite to implement automated real time decision support systems at a farm level.

Canopy Segmentation Method for Determining the Spray Deposition Rate in Orchards

The effective quantification of deposition rate is of vital importance in optimizing the application performance and the utilization of pesticides; meanwhile, the canopies of fruit tree orchards are large, with dense branches and leaves shading each other, making it difficult to quantify spraying efficiency. Therefore, it is imperative to develop a facile methodology for assessing the performance of different spraying techniques in terms of distribution and utilization rate in orchards. To evaluate spraying efficacy in orchards, a canopy segmentation method was developed in to be able to determine the spray deposition rate. The distribution and deposition rate of spray liquid applied using three kinds of orchard sprayer were measured in a pear orchard and a peach orchard. The test results showed that the trailer sprayer had the highest deposition rates, with values of 31.54% and 56.92% on peach and pear trees, respectively. The deposition rates of the mounted sprayer in the peach and pear canopies were 21.75% and 40.61%, and the rates of the hand-held sprayer were 25.19% and 29.97%, respectively. The spray gun had the best droplet distribution uniformity, with CVs of the spray in the peach and pear canopies of 20.54% and 25.06%, respectively. The CVs in the peach and pear canopies were 35.98% and 26.54% for the trailer sprayer, and the CVs of the mounted sprayer were 92.52% and 94.90%, respectively. The canopy segmentation method could effectively be used to calculate the deposition rate and drioplet distribution in orchard application, while a great deal of time was consumed by counting the number of leaves in the different areas of the fruit tree canopies. Therefore, research on the density of branches and leaves in fruit tree canopies should be carried out in order to improve the efficiency of fruit tree canopy information extraction.