Hazelnut Plantations Research Articles

ОПЫТ ПРИМЕНЕНИЯ ПЕРСПЕКТИВНЫХ ГЕРБИЦИДОВ В ООО "ФУНДУК АЛАНИИ" ИРАФСКОГО РАЙОНА РСО-АЛАНИЯ

The fight against weeds in crops and plantings of agricultural crops, both annual and perennial, has been and remains one of the most important scientific problems of agricultural production. The relevance of the research lies in a comprehensive study of the effectiveness of the use of modern promising herbicides in hazelnut orchards, in order to optimize measures to combat weeds. The research results made it possible to develop a system for maintaining soil in a walnut orchard using modern herbicides. To solve the problem, it is necessary to conduct geobotanical studies of the weed component in the walnut orchard, to determine the magnitude of the negative impact of various doses of herbicides in the inter-rows and rows of hazel. The authors first obtained data on the use of herbicides on gray forest soils, with alluvial deposits, skeletonized and rocky in the Iraf region of the Republic of North Ossetia, which are characterized by a humus content of 6-8%, phosphorus up to 200 mg/kg, potassium up to 42 mg/kg and acidic reaction of the soil solution (pH 5.1). The object of the study was weeds in perennial walnut plantations, among them difficult-to-eradicate root shoot thistles (Cirsium arvense), (Sonchus arvensis), creeping bitterweed (Acroptilon repens); rhizome creeping wheatgrass (Agropirum repens) and others. It was established that the use of herbicides Lontrel -300, VR (3 l/ha), Hurricane Forte, VR (2 l/ha), Basta, VR (5 l/ha), Sprut Extra VR (3 l/ha) reduced the number of weeds ranging from 84.8% to 89.9%. Recommendations are given on the timing of application of the most promising herbicides in perennial hazelnut plantations. The predominant effectiveness among the herbicides studied was shown by Octopus Extra VR.

An Example of a New Approach, New Assessment, New Statistical Inference, and New Conclusions from the Published Research by Nikipelova, O., Pyliak, N., & Hodorchuk, V. (2023). Organic fertilizers in increase of hazelnut yield. Interdepartmental Thematic Scientific Collection of Phytosanitary Safety, (69), 118-128. https://doi.org/10.36495/1606-9773.2023.69.118-128.

Background: The declining availability of traditional organic fertilizers and the need for sustainable waste management solutions have sparked interest in alternative nutrient sources for agriculture. This study investigates the potential of sewage sludge-based biofertilizers in hazelnut (Corylus avellana L.) cultivation, addressing both agricultural productivity and environmental concerns. Objective: To evaluate and compare the effects of sewage sludge-based biofertilizers with traditional organic fertilizers on soil agrochemical properties and assess their environmental safety in hazelnut plantations in the Southern Steppe of Ukraine. Methods: A two-year field experiment (2021-2022) was conducted, comparing six treatments: control (no fertilizer), cattle manure, chicken manure, two formulations of sewage sludge-based biofertilizers, and pure sewage sludge. Soil samples were analyzed for easily hydrolyzable nitrogen, mobile phosphorus and potassium, organic matter content, and ecotoxicity. Advanced statistical analyses, including ANOVA, Tukey's post-hoc tests, paired t-tests, and correlation analyses, were employed to assess treatment effects and temporal changes. Results: Statistically significant differences were observed between fertilizer treatments for all major nutrients (p < 0.05). Sewage sludge-based Biofertilizer No. 1 demonstrated superior performance in increasing soil phosphorus content compared to traditional organic fertilizers (306.30 mg/kg vs. 174.75 mg/kg for cattle manure, p < 0.05). All organic fertilizers, including biofertilizers, significantly improved soil nitrogen content over the two-year period (p < 0.05). Potassium levels showed a significant increase (13.41% year-over-year, p < 0.05), while changes in nitrogen and phosphorus levels suggested positive trends but did not reach statistical significance. Importantly, ecotoxicity levels remained low (E < 1.5) across all treatments, indicating minimal short-term environmental risk. Conclusions: This study provides compelling evidence for the potential of sewage sludge-based biofertilizers as effective and environmentally safe alternatives to traditional organic fertilizers in hazelnut cultivation. The findings have significant implications for sustainable agriculture, waste management, and circular economy practices. However, long-term studies are recommended to fully assess the cumulative effects on soil health, crop productivity, and potential contaminant accumulation. This research contributes to the development of innovative, sustainable fertilization strategies that can address both agricultural productivity and environmental conservation needs.

Distribution of Colchicum speciosum Steven in Trabzon Province, Türkiye

Colchicum speciosum Steven belongs to the Colchicaceae family and is native to the Eastern Black Sea Region of Anatolia. The genus Colchicum is used in the pharmaceutical industry due to the colchicine alkaloids contained in both its corms and seeds. This study was carried out to determine the distribution areas of Colchicum speciosum, an important medicinal aromatic plant, in Türkiye. To reach this purpose, field studies were carried out, collecting samples of the plant during suitable vegetation periods between 2015 and 2021 in Trabzon province. The present study was done using a full-field screening method. All field information about the taxon was recorded in the GIS database, and the distribution map of the taxon including Trabzon province was created. It was determined that Colchicum speciosum has a wide distribution in the study area, from 349 to 2560 m asl. In the study area, the specimens was determined at 192 different points and 12 different habitat types. These habitat types are mainly: pasture-meadow areas, both deciduous and conifer forest clearings, agricultural areas, hazelnut plantations, deciduous forests, coniferous forests dominated by Picea orientalis, roadsides, stony areas, scrubs, beech forests, seasonal stream edges, and swamp-reed areas. Additionally, it has been observed that the flowering time of the plant is between September and October.

Powdery mildew caused by Erysiphe corylacearum: An emerging problem on hazelnut in Italy.

Erysiphe corylacearum has recently been reported in northern Italy (Piedmont) and other European countries as the causal agent of a new emerging powdery mildew on hazelnut. This disease is much more dangerous than the common hazelnut powdery mildew caused by Phyllactinia guttata as it significantly reduces yield and quality of hazelnuts. This study aimed to perform morphological and molecular characterization of the fungal isolates from powdery mildew-infected plants in the Piedmont Italian region. Additionally, genetic diversity studies and pathogenicity tests were conducted. Thirty-six fungal isolates originating from symptomatic hazelnut plants exhibiting specific powdery mildew symptoms on the superior leaf side were identified morphologically as E. corylacearum. Single- and multilocus sequence typing of five loci (ITS, rpb2, CaM, GAPDH and GS) assigned all isolates as E. corylacearum. Multilocus and GAPDH phylogenetic studies resulted in the most efficient characterization of E. corylacearum. Studied fungal isolates were able to cause new emerging powdery mildew disease by fulfilling Koch's postulates. The emergence of powdery mildew disease in Italy revealed the E. corylacearum subgrouping, population expansion, and high nucleotide similarity with other recently identified E. corylacearum hazelnut isolates. To contain this harmful disease and inhibit the fungus spread into new geographical zones, it will be necessary to implement more rigorous monitoring in neighboring hazelnut plantations near infected hazelnuts, use sustainable fungicides and search for new biocontrol agents.

Organic fertilizers in increase of hazelnut yield

Goal. To assess the effect of various organic fertilizers on the yield of hazelnut plantations in the conditions of the Southern Steppe of Ukraine.
 Methods. Field experiment, laboratory-analytical, comparative.
 Results. The influence of organic fertilizers of various origins was studied (cattle manure; chicken droppings; Biofertilizer No. 1 — sewage sludge (SW) of the biological treatment station (SBO) «Pivdenna» in Odesa + winter wheat straw + Microbacterium barkeri LP-1 (M. b.); Biofertilizer No. 2 — «Southern» SBO + sunflower seed husks + M. b.; «Pivdenna» SBO, Odesa) on the agrochemical parameters of ordinary medium-humus chernozem in the conditions of the Southern Steppe of Ukraine for the cultivation of hazelnuts. It is shown that in comparison with the control of 2021 and 2022, an increase in the content of easily hydrolyzed nitrogen, mobile forms of phosphorus and potassium, and organic matter is noted in all variants of the experiment.
 Conclusions. The use of organic fertilizers of various origins for the cultivation of hazelnuts in the conditions of the Southern Steppe of Ukraine helps to increase the content of the main agrochemical indicators of the soil — easily hydrolyzed nitrogen (91.0—98.0 mg/kg with 84.0 mg/kg — control), mobile phosphorus compounds (174.75—306.30 mg/kg at 138.75 mg/kg — control), potassium (112.00—166.90 mg/kg at 108.40 mg/kg — control) and organic matter (3.78—4.18% and 3.76% — control). The advantages of biofertilizers No. 1 and No. 2 based on sewage sludge with the use of vegetable fillers (winter wheat straw and sunflower seed husks) and the phosphate-mobilizing bacterium Microbacterium barkeri LP-1 are shown. Organic fertilizers contribute to the increase in the content of nutrients in the soil, the activation of the activity of eco-trophic groups of microorganisms, which leads to an increase in the biological activity of the soil and, accordingly, the yield of agricultural crops.

Land-use pattern and landscape structure impact butterfly diversity and abundance in organic agroecosystems

ContextAgricultural intensification and land-use patterns impact biodiversity and reduce ecosystem functions. Organic farming is often seen as a more biodiversity friendly way of farming. However, not all organic farming is equally supportive for biodiversity, structural diversity of the farms has a great impact and the often high intertwinement of organic and conventional farmland causes spill-over problems.ObjectiveOn organic farmland in central Italy, we analysed butterfly diversity and community structures in different land-use categories across a heterogeneous landscape. We aim to analyse the impact of the different land-use structures such as hedges and forest edges on this farmland, as well as the influence of adjoining conventionally farmed areas.MethodsWe studied butterflies on organic farmland including olive and hazelnut plantations, as well as meadows and fallow land, surrounded by hedges and forests. Hereby we considered the effects of land-use on the studied site and the adjoining land, e.g., semi-natural habitats (as hedges or forest edges), organic or conventional farmland. We counted butterflies along line transects and recorded habitat parameters for each transect. All encountered butterflies were classified according their ecological demands, behaviour, and life-history.ResultsWe found highest mean butterfly species richness in fallow land and lowest in hazelnut plantations. Species community structures differed hardly between plantations and meadows, but considerably compared to fallow land. Butterfly abundances are reduced for olive plantations adjacent to agricultural fields treated with pesticides, compared to such surrounded by organic fields. Habitat para-meters such as the number of flowering plant species and shade impact butterfly diversity and abundance. Forest edges producing considerable shadow to the transects had a significantly negative effect on diversity and abundance, while the influence of hedges was positive.ConclusionsBased on our findings, we conclude that also organic farmland has different degrees of biodiversity depending on a variety of land-use pattern. In particular, habitat heterogeneity and a high diversity of flowers positively influence butterfly diversity. The intensive mixing of organic and conventional agriculture must be seen critical for conservation as negative effects might spill over to organic fields, but might be compensable by landscape structures like hedges.

First report of Erysiphe corylacearum Causing Powdery Mildew on Hazelnut in Hungary.

The interest in hazelnut (Corylus avellana L.) cultivation has recently increased in Hungary, it is currently grown on 490 hectares. In August 2021 early powdery mildew symptoms were observed in a hazelnut plantation, and in a variety collection of the Hungarian University of Agricultural and Life Sciences in Érd. White patches of mycelium and conidia were observed on both side of the leaves. In early October abundant chasmothecia were formed. The disease incidence was 100% on varieties 'Segorbe', and 'Corabel', 70% on 'Ennis', and 30% on the leaves of 'Istrska dolgoplodna leska' (15 plants per cultivar). Powdery mildew is usually caused by Phyllactinia guttata, which was present abundantly on the abaxial and sparsely on the adaxial surface of the observed leaves. However, another fungus co-occurred on the adaxial surface of the leaves, and rarely occurred on the abaxial surface of the leaves. Its morphology differed substantially from P. guttata on having smaller chasmothecia, and branched appendages. The new powdery mildew agent was morphologically described. Mycelium was hyaline, branched, septate, thin-walled and smooth, 2.5-3.1 μm wide. Conidiophores measured 22 to 61 × 5.1 to 8.5 (average: 44.1 × 6.5) μm (n = 30), the foot cells were erect, cylindrical, and flexuous. Conidia occurred rarely and were produced single on conidiophores, 19 to 34 × 15 to 24 μm. Chasmothecia were spherical, 74 to 103 (average: 85) μm in diameter (n = 100), single or in groups on both sides of each leaf. Appendages 7 to 15 per chasmothecium, aseptate, straight, sometimes flexuous with a length of 74 to 118 (average: 103) μm (n = 50), and had 3 to 5 times dichotomous branched apices with curved tips. Each chasmothecium contained 3 to 5 asci. Ovoid to subglobose asci measured 43 to 65 × 32 to 54 μm (average: 56 × 43) μm (n = 30). Asci contained 4 to 8 ascospores which were hyaline, ellipsoid, measured 17 to 23 × 11 to 20 (mean: 21 × 15) μm (n = 40) in diameter. Morphological identification was confirmed by molecular analysis of two samples, one from the plantation, and one from the variety collection. After DNA extraction partial rDNA internal transcribed spacer region (ITS) of the isolates was amplified using primers ITS1_F and ITS4_R, as previously indicated (Meparishvili et al. 2019). Obtained sequences were deposited to the GenBank (accession no. OL744964 and OL744961). BLAST analysis indicated that the two samples were showing 100% and 97,81% identity to ITS rDNA sequences of Erysiphe corylacearum from Switzerland (MN822722), and showed low similarity of 83% and 85% each to P. guttata (AB080558). Pathogenicity tests were accomplished on ten healthy two-year-old plants of C. avellana cv. 'Merveille de Bollwiller' with the two isolates under controlled environment on 25°C, 80% humidity and 16/8 photoperiod. Plants were artificially inoculated by conidial suspension droplets (104/ml). Symptoms appeared after 7-8 days after inoculation and the developing fungus was morphologically identical to the original isolates. Control plants were treated with distilled water, no symptoms were found on them. E. corylacearum was first observed on C. avellana in Turkey in 2013 (Sezer et al. 2017) and was considered as a highly destructive pathogen. It is also known in neighbouring countries, Ukraine (Heluta et al, 2019), Austria (Voglmayr et al. 2020) and Romania (Rosati et al. 2021). To our knowledge, this is the first report of Erysiphe corylacearum in Hungary.

Antioxidants in Shell and Nut Yield Components after Ca, Mg and K Preharvest Spraying on Hazelnut Plantations in Southern Chile.

To determine the effects of pre-harvest calcium (Ca), magnesium (Mg) and potassium (K) spraying on the antioxidant activity and capacity of hazelnut (Corylus avellana L.) shells, as an approach to sustain the utilization of the main residue derived from this industry, four commercial hazelnut (Tonda di Giffoni) orchards located in Southern Chile (Cunco, Gorbea, Perquenco and Radal), during the 2018/19 season were sprayed three times with five combinations of Ca (300 and 600 mg L-1), Mg (300 and 600 mg L-1) and K (300 and 600 mg L-1). Yield components were determined in harvested whole nuts, whereas Ca, Mg and K concentrations, as well as total phenolic compounds, free radical scavenging antioxidant activity, and oxygen radical absorbance capacity, were determined in shells. All spray treatments with both Ca, Mg and K combinations showed a significant interaction between locality and treatment (L × T) on increased stabilized nut yield (kg ha-1) in comparison with the control treatments, whereas nut quality was differentially affected by treatment and orchard locality, thus confirming a significant L × T relationship regarding nut length and kernel yield. However, locality showed a major effect on kernels and shells. A significant relationship was determined between locality and the Ca, Mg and K spraying (L × T) concerning antioxidant compounds such as phenolics, whose amounts exceeded those of the control treatments by three times. Antioxidant capacity and activity in shells showed a significant L × T relationship, and nutshells collected from Cunco showed remarkably (3-4 times) higher levels of these factors than the other evaluated localities. Interactions between spray treatment and orchard location were responsible for the different values obtained in the experiments, confirming the influence of the environment on the efficacy of the treatments. Finally, these shells are worth further study as an interesting residue of the hazelnut industry due to their nutritional and antioxidant properties.

Вплив органічних добрив різного походження на мікробіологічну характеристику ґрунту за вирощування фундука

Goal. To evaluate the influence of organic fertilizers of different origins on the number of microorganisms of the main ecological and trophic groups in the soil for the cultivation of hazelnuts in the conditions of the Southern Steppe of Ukraine. Methods. Generalization and analysis of materials of scientific research, microbiological, field, statistical. The results. In the soil of hazelnut plantations, the dynamics of the development of microorganisms of various eco-trophic groups were studied: ammonifiers, nitrifiers, streptomycetes, spore microorganisms, microorganisms that dissolve organic phosphates, microorganisms that dissolve mineral phosphates, nitrogen fixers, oligotrophs. Conclusions. An increase in the number of microorganisms of the main ecological and trophic groups (ammonifiers, nitrifiers, streptomycetes, spore microorganisms, microorganisms that dissolve organic phosphates, microorganisms that dissolve mineral phosphates, nitrogen fixers, oligotrophs) was established due to the introduction of cattle manure and biofertilizers No. 1 and No 2. The parameters of the mineralization – immobilization coefficient (0.02–0.07) indicate the predominance of the processes of synthesis over the destruction of organic matter in all variants of the experiment. The oligotrophic index (indicator of soil availability with easily digestible nutrients) indicates a high availability of nutrients (0.003–0.03). This shows that the use of organic fertilizers of various origins will not disrupt the functional structure of the soil microbial coenosis.

The distortive effect of organic payments: An example of policy failure in the case of hazelnut plantation

Organic farming is supported in the European Union (EU), among others, via area-based organic payments, targeting better environmental standards, as well as consumers’ demand for organic products. Despite the wide interest growing on hazelnut production in non-traditional production areas in Italy, supply of organic hazelnuts remains negligible. At the same time, evidences show that Italian farmers can receive organic payments, while plantation is not yielding and then either switch to conventional production or continue organic production with no harvest. We employ the annual annuity approach in order to check whether organic payment initiates investments that otherwise would have been unprofitable; and whether it can be exploited by a farmer who has never had intention to produce organic hazelnuts. Results suggest that organic support indeed might be distortive and does not stimulate stable conversion to organic production of hazelnuts. In this regard, we recommend that the current policy should be substantially changed by imposing additional restrictions on conventional or no production or by implying additional requirements for receiving organic payments, for instance at least two subsequent organic contracts.

Evaluation of the effects of some watershed characteristics on water and suspended sediment yield in agricultural and forest dominated watersheds

Topography, geological structure and land use play a determinative role in the streamflow and total suspended sediment yield of watersheds having similar climate, soil and vegetation characteristics. In order to facilitate sustainable water resource management and effective land use planning, there is an increasing need for research investigating the effects of these factors. This study was carried out in forested and agricultural dominated subwatersheds of the Big Melen watershed in the Western Black Sea Region of Turkey. Hazelnut plantations are grown on most of the agricultural areas in both watersheds. The forested watershed has a steep topography and its geological structure consists of sandstone-mudstone and sedimentary rock. The agricultural watershed area is larger and unlike the forested watershed, there is argillaceous limestone in its geological structure. The precipitation, streamflow and total suspended sediment yield in the watersheds were measured for two years. The total precipitation of the study area over the two years was 2217.3 mm. The water yield of the forested watershed was 867.6 mm, while that of the agricultural watershed was 654.9 mm. In the two years, the total suspended sediment transported from the forested watershed was 19.51 t ha<sup>-1</sup> and from the agricultural watershed 7.70 t ha<sup>-1</sup>. However, except for the high values measured after an extreme rainfall event, the unit surface suspended sediment yield of the agricultural watershed was found to be higher than that of the forested watershed. These findings showed that watershed characteristics such as slope, geological structure and rainfall intensity may be more effective on the streamflow and total suspended sediment yield of the watersheds than land use.

Combined Spraying of Boron and Zinc During Fruit Set and Premature Stage Improves Yield and Fruit Quality of European Hazelnut cv. Tonda di Giffoni.

Boron (B) and zinc (Zn) are essential micronutrients of plant nutrition programs in orchards for securing the crop quality and yield. Although orchard supplementation with B and Zn is a common practice to overcome deficiencies or maintain their optimal levels, the efficiency of combined B and Zn spraying in relation to European hazelnut (Corylus avellana L.) phenological stage has not been investigated so far. Leaf and kernel mineral and functional traits were studied in cultivar Tonda di Giffoni after B and Zn spraying in four phenological stages. During the 2016/2017 season, 9-year-old trees were sprayed with B (0, 800, and 1,600 mg L−1) and Zn (0, 400, and 800 mg L−1) under three treatments: B0+Zn0, B800+Zn400, and B1600+Zn800 implemented in three spring application programs scheduled from October to December (P1: four times, P2: early two times, and P3: late two times). B and Zn treatments in P1 and P3 led to higher Zn concentration both in leaves and in kernels compared with non-sprayed trees. Stabilized nut production increased 2.5-fold under B800+Zn400 in all three programs. Kernel/nut ratio improved in both B+Zn treatments in P1 and P3, while the percentage of blank nuts was reduced compared with B0+Zn0. Increased radical scavenging activity in B+Zn-treated kernels and leaves was not attributed to the accumulation of phenolics in P3 compared with B0+Zn0, whereas B and Zn spraying reduced the level of lipid peroxidation in both studied organs. According to the results, combined B and Zn should be sprayed at the end of spring (P3) on hazelnut plantations in temperate areas such as Southern Chile, whereas early applications (P2) showed an irregularity in nut production and functional traits in nuts. Moderate and partialized rates of B and Zn and the time of implementation contribute to improving the quantitative and qualitative features crucial for future sustainable hazelnut production.

Short-Term Effects of Spent Mushroom Substrate Mulching Thickness on the Soil Environment, Weed Suppression, Leaf Nutrients, and Nut Characteristics in a Hazelnut Orchard

Worldwide, a huge amount of solid fermented waste is produced every year during mushroom production. The rational utilization of spent mushroom substrate (SMS) is conducive to environmental protection and the sustainable development of agriculture. The aims of this work were to analyze the effects of the SMS mulching thickness on the soil environment, weed suppression, leaf nutrients, and nut traits in a hazelnut plantation and provide a theoretical basis for the scientific and reasonable utilization of SMS. An SMS mulching experiment with four mulching thickness treatments (MT1: 5 cm, MT2: 10 cm, MT3: 15 cm, and CK: 0 cm) was conducted in a semi-arid area of North China in 2019. The soil properties, weed control efficiency, leaf nutrient content, and nut yield and quality characteristics of these treatments were all measured and analyzed. The results showed that (1) the average soil temperatures of MT2 and MT3 at different soil depths were 0.73–1.78 °C and 1.18–2.50 °C lower than when no mulch was used in warm weather and 0.67–1.05 °C and 0.99–1.56 °C higher than when no mulch was used in cold weather. The average soil moisture content of MT1, MT2, and MT3 at different soil depths was 6.27–8.13%, 10.66–17.23%, and 7.26–12.81% higher than that of CK, respectively. There were no significant differences in the soil bulk density or porosity among the four treatments. The average soil nutrient contents (soil organic matter and available N, P, and K) of MT1, MT2, and MT3 were 7.05–15.23%, 14.90–38.93%, and 17.42–40.11% higher than those of CK, respectively. Soil enzymatic activities of these treatments followed the order MT3 ≈ MT2 > MT1 > CK. (2) MT2 and MT3 both had high levels of weed control efficiency: 55.66–92.93% and 70.43–97.90%, respectively. (3) The leaf N, P, K, and SPAD increased significantly under MT2 and MT3 by about 10% compared with the CK. (4) MT2 effectively increased the nut size, nut and kernel mass, and crude fat content of the nut (CFC). In general, the short-term field experiment clearly showed that SMS is a superior mulching material for improving the soil environment and plant growth, and 10 cm thickness is suitable for mulching practice.

Arrhenatherum elatius subsp. bulbosum (Poaceae): A New Alien Record for the Flora of Turkey

Invasive alien species are one of the largest threats to global biodiversity together with social, environmental and economic problems. As well, they present significant threats to global agriculture especially in the regions with moderate temperature as in northeast Anatolia. Arrhenatherum elatius (L.) P. Beauv. ex J. Presl. & C. Presl. subsp. bulbosum (Willd.) Schübl. & Martens (Poaceae) was observed in farmlands, an invasive alien taxon in tea and hazelnut plantations, in Turkey where it was established in a new ecosystem, outside its natural range in SW Europe. In this article, this subspecies was reported as a new alien vascular plant taxon for the Flora of Turkey. At the base of its stems the adjacent nodes are swollen and form a chain of bulbs which characterize this taxon and differentiate it from other subspecies. New Turkish name and photographs of the new record are also presented in the article.

EVALUATION OF THE WORKING RADIUS OF PHEROMONE PREPARATIONS FOR THE BROWN MARMORATED STINK BUG HALYOMORPHA HALYS

This article presents the trial results aimed to evaluate the working radius of the pheromone formulation for the adults of the brown marmorated stink bug Halyomorpha halys under the field conditions in 2019. The cumulative plastic traps of “pyramid” type with a synthetic pheromone preparation manufactured by a Russian producer were used. The chemical composition of the preparation included a mixture of two stereoisomers: (3S, 6S, 7R, 10S)-10.11-epoxy-1-bisabolene-3-ol and (3R,6S,7R,10S)-10.11-epoxy-1-bisabolene-3-ol, and the substance – synergist-methyl-(E,E,Z)-2,4,6-decatrienoate. Previously, this composition had been proved to be effective in catching nymphs and adults of the brown marmorated stink bug during the field trials at the dosage of 12 mg/trap. The results of the 2019 trials showed that when labeled bugs were released in fruit orchards from a distance of 10 m (corresponding to an area of 0.03 ha), the probability of adults’ catching in traps was 9 %. The bug catching probability from the distance of 20 m (an area of 0.1 ha) was lower, reaching only 3 %. The total number of bugs caught in the trap in the hazelnut plantations was half of that in fruit orchards, and the probability of catching of labeled adults released from 10 m (0.03 ha) was 2.5 %.

Relationships between yield and pollen concentrations in Chilean hazelnut orchards

Abstract Chilean hazelnut (Corylus avellana L.) industry has been recently experiencing a solid development and nut production is consistently increasing. Corylus avellana is subjected to strong inter-annual yield fluctuations, which raise the issue of price predictability. In alternate bearing, a high fruit load hinders flower initiation thus leading to a smaller fruits production in the following year. This suggests the use of pollen airborne concentration as a proxy for flowers number to predict hazelnut irregular bearing. We addressed this question using high-resolution yield and pollen data collected on four hazelnut plantations located in Central Chile, and three hazelnut cultivars. Pollen parameters were calculated from modelled and non-modelled pollen seasons, after selecting the best modelling approach. An alternate bearing index was calculated to characterize hazelnut biennial bearing and to select plots with high yield variability. The calculated pollen parameters were then correlated with yield data. Significant correlations were found between pollen parameters and nut yields, with stronger relationship when alternate bearing was higher. The modelled peak of the pollen season presented the highest variability (average CV = 81 %) and its positive correlation with crop production (ρ = 0.45) was consistent across sites and cultivars. Our results support the integration of airborne pollen data in hazelnut yield prediction systems, as predictors of alternate bearing and to forecast annual yield.

АНАЛИЗ ПРОИЗВОДИТЕЛЬНОСТИ ПОСАДОЧНОГО АГРЕГАТА ПРИМЕНИТЕЛЬНО К ФУНДУЧНЫМ ПИТОМНИКАМ

Relevance and methods. Special machines for nurseries of the future hazelnut garden are not produced. The use of landing machines for this purpose requires appropriate technological and mechanical improvement. Due to the complexity and high volume of manual labor, it is necessary to find ways to increase the productivity of existing landing machines. The object of the research was the working process of the planting machine in the nursery for hazelnut plantations, the analysis of the productivity of the planting unit. Results. It is established that a more advanced technological process of transfer of seedlings, embodied in the machine, in which the planting machine is served by one worker, allows to reduce labor costs by 45% compared to the indicator when using the existing planting machine.

First Report of Powdery Mildew Caused by Erysiphe corylacearum on Hazelnuts in Georgia

Hazelnuts (Corylus avellana) are widely grown in the Republic of Georgia and considered a major agricultural export product (Gurcan et al. 2010). Powdery mildew in hazelnut trees is a major disease that causes significant yield loss (Sezer et al. 2017). Until recently, Phyllactinia guttata was considered the main causal agent in the neighboring countries of Western Asia and the Caucasus (Abasova et al. 2018; Arzanlou et al. 2018). However, in the last 3 years a new destructive species, Erysiphe corylacearum, has been identified as a pathogen of powdery mildew on hazelnut in the neighboring countries of Iran, Azerbaijan, and Turkey (Abasova et al. 2018; Arzanlou et al. 2018; Sezer et al. 2017). During May and July 2018, powdery mildew symptoms were observed in hazelnut plantations of the cultivar Anakliuri in Adjara region (western Georgia). Symptoms were observed on the upper leaf surface and fruit clusters including husks. Disease incidence reached 100%, and severity ranged between 10 and 70%. On heavily affected leaves, necrotic lesions were observed 9 to 13 days after the first symptoms appeared, followed by leaf curling and defoliation. Morphological characterization of leaf and husk samples showed the following characters: hyphal appressoria (n = 30) were lobed, solitary, 1 to 4 μm in diameter; mycelium was amphigenous, hyaline, branched, septate 1.8 to 5.3 μm wide; conidiophores (n = 35) vertically elevated above the mycelium 53 to 82 μm long and 5 to 12 μm wide; produced solitary conidia (n = 50) on conidiophores, hyaline, ellipsoid to ovoid, 24 to 36 μm long, 14 to 24 μm wide. Chasmothecia appeared in early October. They were spherical, single or in groups, 73 to 104 μm in diameter, appendages six to 15 straight, 72 to 101 μm long, four to five times dichotomous branched, aseptate or one with a septum at the base. In each chasmothecium, there were three to five asci (n = 50) with a width of 38 to 53 μm and a length of 26 to 38 μm of oval-ellipsoid shape. Asci contained four to eight ascospores (n = 50), 18 to 25 μm long and 8 to 12 μm wide. Pathogenicity testing was conducted according to Koсh’s postulates. Two-year-old plants of C. avellana, cultivar Anakliuri, were artificially infected by dusting conidia from infected leaves (n = 25). Inoculated plants were incubated under 20 to 28°C and 70 to 80% humidity. Typical symptoms (fluffy white bloom) appeared on the upper surface of the leaves within 8 to 10 days after inoculation. No symptoms were found on control plants treated with sterile water. The fungus isolated from the inoculated leaves (n = 25) was morphologically identical to the original isolates from natural diseased plants (n = 10). DNA was extracted, and the rDNA internal transcribed spacer region of four isolates was amplified using primers ITS1 and ITS4 and sequenced. BLAST analysis of our 593-bp fragments (all identical and represented by GenBank accession no. MK157199) showed 99% identity to ITS rDNA sequences of E. corylacearum from Azerbaijan (LC270863) and Turkey (KY082910) and only 83% similarity to P. guttata (accession no. AB080558).

A search for naturally grown Burgundy truffles (Tuber aestivum) on hazelnut plantations in Germany: Results of a survey

To overcome the increasing strain on agricultural crop production in Central Europe, new management practices are in demand that allow for sustainable farming systems while providing the farmers with a reliable income. One option is the establishment of hazelnut plantations (Corylus avellana) to produce and sell hazelnuts. A possibility to further increase benefits from hazelnut plantations might be offered by harvesting summer truffles (or Burgundy truffles, Tuber aestivum), a species that frequently forms mycorrhizae with hazelnut trees in the wild. Consequently, a first systematic survey was undertaken to assess the potential presence of naturally grown T. aestivum on 14 existing hazelnut plantations in Germany using trained truffle dogs. Naturally grown Burgundy truffles were not found on the visited plantations. The dogs unearthed eight other species of hypogeous fungi. Hazelnut farmers should not be too optimistic that naturally grown T. aestivum will provide them with a noteworthy additional income from their plantations.

Molecular characterization and sequence detection of Apple mosaic virus hazelnut isolates

One of the most important factors, limiting the production of hazelnut in Turkey is Apple mosaic ilarvirus (ApMV). Due to the easy distribution of the pathogen by vegetation and pollen, there is no chemical control available, it causes widespread dissemination in both pome fruit and hazelnut plantations in Turkey. The pathogen was detected on several plant species in Turkey: stone and pome fruits, roses and finally hazelnut. Virus isolates were collected from mainly hazelnut production areas in Black sea region of Turkey and analyzed by DAS-ELISA and RT-PCR assays. During the surveys, 95 hazelnut samples were collected from the research area and using DAS-ELISA it was determined that 57 of them were infected by ApMV. Different RNA isolation methods were tested because of the high tannin content of the leaves, the best results were obtained using the procedure of Rott and Jelkmann (2001) and 262 bp long amplification products were obtained in RT-PCR tests. 9 hazelnut isolates collected from different locations were sequenced and phylogenetic analysis were performed by Mega programme. According to the results of phylogenetic analysis. Hazelnut sequences were gathered in different clusters and compared to the other hosts of the virus.