2022, Vol. 20, No. 2

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/7700

Sirvi

Nüüd näidatakse 1 - 19 19

Risk factors for honey bee (Apis mellifera L.) mortality in Estonian apiaries during 2012–2013
(Estonian University of Life Sciences, 2022) Tummeleht, Lea; Orro, Toomas; Viltrop, Arvo; Estonian University of Life Sciences. Institute of Veterinary Medicine and Animal Sciences
In light of the global increase in honey bee colony losses, risk factors regarding beekeeping management practices and honey bee diseases have been studied intensively during the last decade. Some risk factors have been outlined, but the correlation of evidence between relevant factors coinciding with honey bee mortality still needs to be clarified. The current study used the two-year data collected in frames of the European Commission EPILOBEE project. Previously, the data from Estonian apiaries were analysed together with the data from all 17 participating European countries in the consortium. In the current study, data from Estonian apiaries were targeted separately. In total, 196 apiaries containing 2,439 colonies all over Estonia were included in this dataset. The study aimed to clarify the risk factors that would predict colony losses in Estonia. The main factors increasing colony mortality after winter were the size of the apiary, Varroa destructor mite count, infestation with Paenibacillus larvae, and lack of farmlands around the apiary. No significant risk factors in relation to honey bee summer mortality were detected.
Efficiency of productivity potential realization of different-age sites of a trunk of grades of columnar type apple-trees
(Estonian University of Life Sciences, 2022) Havryliuk, O.; Kondratenko, T.; Mazur, B.; Tonkha, O.; Andrusyk, Y.; Kutovenko, V.; Yakovlev, R.; Kryvoshapka, V.; Trokhymchuk, A.; Dmytrenko, Y.
An article provides information about buds organogenesis in plants of columnar apple cultivars in the Forest-Steppe of Ukraine (Kyiv), which allows to establish the features of this process in complex fruit formations of different ages, and their productivity and longevity. We recommend studying of apple trees productivity in the process of its formation by analyzing of rudimentary organs formation and their consistent development into vegetative and generative organs, which are elements of productivity. Studies of organogenesis different-age fruit formations of columnar apple cultivars were conducted in the northern part of the Forest-Steppe of Ukraine during 2016–2020. It was established that separate age sections of columnar apple trees trunk formed different initial productivity potential. In plants of all studied varieties and age groups, the laying of generative buds, the implementation of reproductive elements in V–IX and X–XI stages of organogenesis were more effective in older age areas of the trunk. Complex fruit formations, regardless of the trunk age where they are placed, form a high potential for productivity, which is effectively realized. The dependence of the formation and productivity potential realization on the stages of organogenesis and meteorological factors is established.
Growth characteristics of American Ginseng (Panax quinquefolius L.) woods and field - cultivated at Northern Europe
(Estonian University of Life Sciences, 2022) Kronberga, A.; Nakurte, I.; Kaļāne, L.; Abaja, R.; Berga, M.; Primavera, A.; Mežaka, I.
In Latvia, Northern Europe, American ginseng was grown in three forest types with different dominant species, as well as in agricultural field conditions - cultivated under artificial shade with three different types of mulches. Field cultivation yielded higher yields, root length, and root weight than wood cultivation under dominant species Corylus avellana, Betula pendula, and Picea abies. Mulching had a positive impact on ginseng growth in the field. Mulching with straw and buckwheat hulls resulted in longer and heavier roots. In American ginseng roots, the contents of six ginsenosides were determined: Rg1, Re, Rb1, Rc, Rb2, and Rd. Re was the most abundant ginsenoside, followed by Rb1 > Rd > Rg1 = Rb2 > Rd. The total content of ginsenosides in our study did not reach the 4 percent threshold set by US Pharmacopeia. These findings show that Panax quinquefolium can be grown in Northern Europe at 57°N, but it takes more than four years to achieve adequate yields and ginsenoside content.
Biogas production from the specialized dairy farming and porcine subsectors in Antioquia, Colombia: theoretical and technical-energy potential approach
(Estonian University of Life Sciences, 2022) Luna-del Risco, M.; Jiménez Vásquez, A.; Zea Fernández, J.S.; Marín, E.; Arrieta González, C.; Cardona Vargas, A.; Mejías Brizuela, N.Y.
In developing countries, residual biomass usage by means of anaerobic digestion offers several benefits and opportunities, such as a sustainable energy source, production of organic fertilizers and new agrobusiness models. In Latin America, Colombia is one of the most promising markets for the implementation of this technology in terms of availability of biomass and economic growth, as recently reported by local government organizations. In this paper, special attention is given to Antioquia, a department of Colombia with the largest farms of cattle and pigs, according to information reported in 2018 by the Ministry of Agriculture and Rural Development. It is estimated that manure from the porcine subsector in Antioquia has an approximate technical-energy potential of 1,896 TJ year-1 , varying from 1,611 to 2,186 TJ year-1 , corresponding to the 95% confidence interval. In the case of manure generated by the livestock subsector in Antioquia, it is estimated a theoretical energy potential of 8,566 TJ year-1 . However, traditional extensive production systems disseminate manure through the pastures turning centralization of the available residual biomass a difficult task and not senseful. Based on the local practices of the specialized dairy subsector, it is estimated that manure collected during the milking process could reached up to 25% of the total available. Biochemical conversion of this amount of biomass has an estimated technical-energy potential of 187 TJ year-1 , varying from 156 and 236 TJ year-1 , corresponding to the 95% confidence. The aim of this article is to estimate the technical-energy potential for the livestock and porcine subsectors in the Department of Antioquia, based on the available residual biomass according to local farming practices.
Adaptation of various maize hybrids when grown for biomass
(Estonian University of Life Sciences, 2022) Radchenko, M.V.; Trotsenko, V.I.; Butenko, A.O.; Masyk, І.M.; Hlupak, Z.I.; Pshychenko, O.I.; Terokhina, N.O.; Rozhko, V.M.; Karpenko, O.Y.
The aim of this research is to optimize growth and development of maize for biomass by selecting maize hybrids to fulfill their productivity potential. The following maize hybrids were the subject of research: Forteza, DM Native, DM Skarb. The greatest height of plants was formed in the interphase period of milk-wax maturity of grain in hybrid Forteza - 286.4 cm. In hybrid DM Native the height of plants was - 271.2 cm, hybrid DM Skarb - 263.6 cm. Weight of one plant of hybrids studied during the maize growing season ranged from 442 g to 760 g. Thus, the largest mass of maize plants was recorded in the milk-wax maturity stage. It was the largest at the hybrid Forteza and amounted to 760 g, that is more than at the hybrid DM Native for 3.4% (26 g) and at the hybrid DM Skarb for 6.6% (50 g). The average crop yield of the hybrid Forteza for the period of research was 55.1 t ha-1 . Hybrids DM Native and DM Skarb provided this indicator at the level of 50.6 and 45.7 t ha-1 respectively. Hybrid Forteza provided a maximum crop yield 55.1 t ha-1 with plant height 286.4 cm, assimilation surface of one plant and a crop 0.59 m2 ; 42.8 thousand m2 ha-1 and plant weight 760 g.
The effect of adding carrot or beetroot powders on the quality indicators of round cracknel products
(Estonian University of Life Sciences, 2022) Tikhiy, A.V.; Barakova, N.V.; Samodelkin, E.A.
The relationship between carrot/beetroot powders added, the quantity and quality of gluten in the flour and the moisture, acidity, swelling coefficient and the quality indicators of round cracknel products has been studied. The carrot and beetroot powders, produced by Vitbiokor, LLC, and the premium wheat flour were used. The powders were introduced in a dry and hydrated form. The hydration was carried out at the hydromodule of 1:5 for 40 minutes. The particle size analysis of raw materials was conducted with the laser diffraction analyzer Malvern Mastersizer 2000. The proportion of particles of less than 200 µm in the flour made 100%, in the carrot powder - 77%, in the beetroot powder - 71%. The introduction of carrot/beetroot powders in the amount of 1.5%, 3.0%, 6.0% and 9.0% by weight of the flour reduces the amount of gluten. Still, it strengthens the latter, making it possible to mold products with developed porosity. The introduction of dry carrot powder in the amount of 6% into the sourdough and the dough (1.5%, 3.0%, 6.0% and 9.0%) increases the swelling coefficient of the end products by an average of 15%, while the introduction of the hydrated powder does it by 40%. Similarly, the introduction of the dry beetroot powder leads, on average, to a 12% increase and of the hydrated powder to a 22% increase. The obtained results proved the effectiveness of introducing carrot/beetroot powders (preference given to their hydrated types) into the recipe of round cracknel products.
Non-destructive identification of defects and classification of Hass avocado fruits with the use of a hyperspectral image
(Estonian University of Life Sciences, 2022) Metlenkin, D.A.; Platov, Y.T.; Platova, R.A.; Zhirkova, E.V.; Teneva, O.T.
Sensory analysis and instrumental analytical methods are used in determining the maturity and quality monitoring of avocado fruits, which are labor-intensive and do not allow the determination of fruit quality in real time. The use of hyperspectral imaging (HSI) methods in the range of 400–1,000 nm and of the multivariate analysis was demonstrated for a non-destructive grading of Hass avocado fruits into quality classes according to the number of hidden defects. Using the sensory analysis, avocado fruits were separated into quality classes according to the number of defects after being stored for 10 days. Development of a classification model included several steps: image recording and analysis using the ANOVA and PCA method, image segmentation (selection of ROI), pre-processing (SNV-correction, centering), selection of a multivariate classification method (PLS-DA, SIMCA) and a spectral range, model verification. The analysis of hyperspectral images of avocado fruits has detected spectral regions with the maximal variance responsible for the change of the content of pigments and moisture within the avocado fruit exocarp. Comparison of PLS-DA and SIMCA models on the basis of best accuracy and test-validation results was carried out. Comparison of models showed SIMCA model as the most efficient model for fruit classification into quality classes depending on the number of hidden defects. The implementation of the developed approach as a digital avocado fruit sorting system at different stages of the product life cycle is proposed.
Morphological and anatomical characterization of Actinidia kolomikta (Rupr. & Maxim.) Maxim. (C3) and Amaranthus tricolor L. (C4) leaves
(Estonian University of Life Sciences, 2022) Motyleva, S.; Vlasova, E.; Kozak, N.; Gins, M.; Gins, V.
Morphological and anatomical features of new cultivars with photosynthesis of C3 (Actinidia kolomikta (Rupr. & Maxim.) Maxim. cv. ‘Narodnaya’) and C4 (Amaranthus tricolor L. cv. ‘Valentina’) were established by light and scanning electron microscopy, as well as energy-dispersive analysis. The leaf lamina of Actinidia kolomikta cv. ‘Narodnaya’ has a dorsoventral anatomical structure, anomocytic stomata on the abaxial epidermis and two types of trichomes: multicellular, uniseriate hairs and multicellular bristle-like protrusions, containing raphids. The needle-like raphides are located in subepidermal layers along the veins. A vascular system of petiole consists of two upper concentric bundles and the crescentic vascular strand. A starch sheat is present. Raphides (needle-shaped and rectangular) are located in phloem and cortical parenchyma cells, contain Ca, K, Mg, P and Si. The leaf lamina of Amaranthus tricolor cv. ‘Valentina’ have the kranz-anatomy, dorsiventral mesophyll and contain druses. Betacyanins are concentrated in the epidermis and mesophyll, but are not present in the bundle sheath. The number of vascular bundles in petioles is odd-numbered and variable (from 5 to 13). Trichomes are multicellular, uniseriate, ending in a large oval cell. Cells with betacyanins are present in the epidermis cortex, and, rarely, the collenchyma and phloem of the petiole. Cells with betaxanthins are absent. A starch sheat is brightly pigmented with betacyanins. The crystall sand is deposited in the parenchyma cells of the cortex and pith of the petiole and contains Ca (mainly) and K oxalates. Druses in the leaf lamina additionally contain Mg and P.
Amino acid content in rice and lentil meal for vegan and pescatarian diet
(Estonian University of Life Sciences, 2022) Lignicka, I.; Graci (Balgalve), A.; Zīdere-Laizāne, A.M.
Combining different raw materials, it is possible to increase plant-based protein functionality. Traditionally lentils are combined with rice. As rice complements lentils in sulphurcontaining amino acids this plant-based combination provides a complete profile of essential amino acids. The aim of this study was to compare amino acid content and scoring pattern in vegan and pescatarian quick preparation meals and analyse developed meal suitability for a vegan diet containing all needed amino acids. Results show that vegan and pescatarian quick preparation meals contain all essential amino acids at adequate amounts according to FAO`s recommendation, results showed no significant difference between samples (p > 0.05). These results show that combining rice and lentils it is possible to develop a meal suitable for a vegan diet that contains all needed amino acids.
Indemnities to Russian farmers for losses due to extreme weather event losses: the challenges and opportunities
(Estonian University of Life Sciences, 2022) Nosov, V.V.; Vorob’eva, D.A.; Udovik, E.E.; Zhenzhebir, V.N.; Morkovkin, D.E.; Gibadullin, A.A.
The paper aims to examine indemnity payments to Russian farmers for weather-related loss. Indemnity payments can be made as crop insurance payments or direct payments from budget. The manuscript presents the official data on damage caused by extreme weather and the amount of insurance payments and direct payments to farmers for the years 2005–2021. To process the results of our research, we performed correlation and regression analysis using STATISTICA package. We presented the results of the research in tabular and graphical forms. The research revealed that the average proportion of insurance payments for crop losses in indemnity payments to farmers is 22.1%, and direct payments from budgets of various levels amount to 25.7%. Indicatively, 52.2%% of damage remains uncompensated. According to findings, RUB 1 billion in premium subsidies raises insured area by 0.14% under a steady trend, while other factors result in reduction by 1.1%. The paper reviews the barriers that hinder the development of subsidized crop insurance. We propose a series of measures that can promptly improve the current situation, such as the stabilization of the legal framework, a tighter control over insurance rates and the need for authorities to stem corruption. We also note that in setting insurance rates, it is important to consider the farming techniques, selective breeding potential, and adoption of index insurance.
Evaluation of the honey bee colonies weight gain during the intensive foraging period
(Estonian University of Life Sciences, 2022) Zacepins, A.; Ozols, N.; Kviesis, A.; Gailis, J.; Komasilovs, V.; Komasilova, O.; Zagorska, V.
Beekeeping in Latvia has a long tradition and it is a classical branch of agriculture. In Latvia, there is no traditional beekeeping region, and beekeeping is performed in all regions. Honey yield is influenced by various factors - variety of crops (nectar plants) around the apiary, man-made changes in land/forests (deforestation), climate change, beekeepers’ actions, etc. Application of information and communication technologies (ICT) in the field of beekeeping can bring benefits to the beekeepers. To be more specific, continuous remote monitoring of certain bee colony parameters can improve beekeeper’s apiary management, by informing timely about the nectar flow (or even provide information on bee colony states, e.g., swarming). In such a way, beekeepers can plan their next actions - prepare supers or even choose to move the apiary to a different geographical location. Within this research, weight gain of the ten honey bee colonies was remotely monitored and analysed during two-week period at the beginning of the summer 2021 in Vecauce, Latvia, using the precision beekeeping approach. This monitoring period corresponded to intensive flowering of the winter rapeseed and field beans. Colonies were equipped with the automatic scales. In addition, colony and environmental temperature was monitored. Measurements were taken every thirty minutes. Analysing the obtained data, weight increase can be observed in all colonies, from 17 to 48 kg. As well, based on weight data, swarming event can be identified. Constant monitoring of weight change can also help to identify daily patterns in honey bee activity.
Agrochemical methods for reducing the translocation ability of heavy metals in sod-podzolic soil
(Estonian University of Life Sciences, 2022) Mazhayskiy, Yu.A.; Guseva, T.M.; Kurchevskiy, S.M.; Vcherashnyaya, V.V.
The impact of technogenesis on the agricultural landscape contributes to the contamination of all its components by heavy metals. The main measure to protect the environment from the input of heavy metals is the prevention of pollution, which is achieved by improving the technology of agricultural production. The development of methods for the agrochemical rehabilitation of technogenically polluted soil, which ensure the receipt of environmentally safe crop products, is an urgent task. The paper presents the results of a lysimetric experiment on the study of the use of fertilizer systems for the purpose of remediation of heavy-metal-contaminated soddy-podzolic soil. It has been experimentally established that the translocation ability of heavy metals and, as a result, the accumulation of toxicants in grain and tilled crops is reduced when using an organomineral fertilizer system. All the studied fertilizer systems reduced the entry of dangerous ecotoxicants - lead and cadmium, into the infiltration water, and also caused the immobilization of Cu and Zn.
Mapping drainage ditches in agricultural landscapes using LiDAR data
(Estonian University of Life Sciences, 2022) Melniks, R.; Ivanovs, J.; Lazdins, A.; Makovskis, K.
The aim of this study is to develop a method for identification of the drainage ditch network, which can be used for surface runoff modeling and to increase accuracy of estimation of greenhouse gas (GHG) emissions in croplands and grasslands, using remote sensing data. The study area consists of 11 objects throughout Latvia with a total area of 145 km2 . Digital elevation models (DEMs) in two resolutions, which were created using three different interpolation methods, were used for the analysis. Several multi-level data filtering methods were applied to identify ditch network, including flow patterns, which can be used in surface runoff process. The method we developed correctly identified 85–89% of ditches, depending on the DEM used, in comparison to the reference data. Mapped ditches are located within 3 m range of the reference data in 89–93% of cases. The elaborated model is robust and uses openly available source data and can be used for large scale ditch mapping with sufficient accuracy necessary for hydrological modelling and GHG accounting in the national inventories.
False flax (Сamelina sativa L.) and oil flax (Linum usitatissimum L.) – an important source of deficient omega-3 fatty acids
(Estonian University of Life Sciences, 2022) Lykhochvor, V.; Olifir, Y.; Panasiuk, R.; Tyrus, M.
Spring false flax (Camelina sativa L.), oil flax (Linum usitatissimum L.), spring rape (Brassica napus oleifera annua Metzd.), white mustard (Sinapis alba L.), and blue mustard (Brassica juncea Czern) were studied in order to establish their yield, oil content and quality. It was found that the highest seed yield (2.82 t ha-1 ) was formed by spring rape. Yields were also high in spring false flax (2.68 t ha-1 ) and oil flax (2.34 t ha-1 ). It was found that the highest oil content was in oil flax (52.2%), blue mustard (45.8%) and false flax (45.0%). The highest oil yields were provided by spring rape, false flax and oil flax - 1.21–1.25 t ha-1 . It was found that the most physiologically valuable are oil flax and false flax, which have a high content of omega-3(ω-3) fatty acids. It is advisable to use it for therapeutic, prophylactic and dietary purposes. The cultivation of false flax and oil flax is economically feasible and provides an environmental effect due to the reduction of pesticides.
Assessment of power characteristics of unmanned tractor for operations on peat fields
(Estonian University of Life Sciences, 2022) Kägo, Riho; Vellak, Priit; Ehrpais, Hendrik; Noorma, Mart; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
In this article, power characteristics of a state-of-the-art unmanned ground vehicle (UGV) are characterised. It is demonstrated that in terms of power characteristics requirements, purposebuilt computer aided autonomous UGV systems are capable of replacing systems that utilise conventional tractors in peat field operations, with milled peat extraction operations as a case study. The authors demonstrate the viability of the UGV in achieving optimal mobility capabilities in operating on peatland surface. The UGV of interest was assessed for two operations of milled peat extraction: milling and harrowing. For both operations, the power consumption of the UGV and the drawbar pull of the implements (passive miller and harrower) were measured and analysed. The required drawbar pull values of the investigated implements remained in the range of 4–8 kN, which corresponded to the drawbar power of 14–36 kW. It was found that the UGV of interest is capable of carrying out milled peat operations in terms of traction capacity. However, it was found that the power supply capacity to be insufficient, thus requiring an improved solution.
Effect of the Lactation Months on Milk Composition of the Second-Parity Lacaune Ewes
(Estonian University of Life Sciences, 2021) Tatar, Vilma; Tänavots, Alo; Polikarpus, Annemari; Sats, Andres; Arvi, Eleri; Mahla, Tauno; Jõudu, Ivi; Estonian University of Life Sciences. Institute of Veterinary Medicine and Animal Sciences. Chair of Food Science and Technology; Estonian University of Life Sciences. ERA Chair for Food (By-) Products Valorisation Technologies of the Estonian University of Life Sciences (VALORTECH)
This research aims to determine the chemical composition of Lacaune ewe milk produced in Estonia, as well as the correlations and the influence the stages of lactation have on milk. The study was carried out on fifty-one second-parity ewes. The analysis involved a total of 178 milk samples collected monthly from the second to the seventh month of lactation. Milk analyses included the determination of the contents of total solids, fat, total protein, casein, casein index, lactose, ash, P, Ca, K, Na, Mg, somatic cell count and pH. The Lacaune ewes’ milk contained on average 18.62% total solids, 7.75% fat, 5.74% total protein, 4.32% casein, 4.76% lactose, 0.89% ash, 160.26 mg 100 g -1 Ca, 140.07 mg 100 g -1 P, 135.21 mg 100 g -1 K, 46.44 mg 100 g -1 Na, 17.66 mg 100 g -1 Mg. Overall means for casein index, pH value and somatic cell scores were 75.35%, 6.61 and 12.62, respectively. It was found that the month of lactation significantly affected almost all monitored traits except somatic cell score, casein index and Ca content. The contents of total solids, fat, total protein, casein, ash, P, and Mg increased, while the lactose content, and pH value decreased with the advancing lactation. Sodium content was highest and potassium content lowest value during mid-lactation. Producers must take into account that the composition of Lacaune ewe milk depends on the stage of lactation and may, therefore, affect the production process and the final quality of the product.
A mathematical model of the rear-trailed top harvester and an evaluation of its motion stability
(Estonian University of Life Sciences, 2022) Olt, Jüri; Bulgakov, V.; Beloev, H.; Nadykto, V.; Ihnatiev, Ye.; Dubrovina, O.; Arak, Margus; Bondar, M.; Kutsenko, A.; Estonian University of Life Sciences. Institute of Technology
Improving the quality of sugar beet harvesting to a great extent depends on the first operation in the process, which involves cutting and harvesting sugar beet tops. This technological process is performed with the use of either the haulm harvesting modules of beet harvesters or top harvesting machines as separate agricultural implements, which are aggregated with a tractor. At the same time, front-mounted harvesters are as widely used as trailed asymmetric implements, in which case the aggregating tractor moves on the already harvested area of the field. The purpose of this work is to determine the optimal design and kinematic parameters that would improve the stability in the performance of the technological process of harvesting sugar beet tops by means of developing the basic theory of the plane-parallel motion performed by the rear-trailed asymmetric top harvester. As a result of the analytical study, an equivalent scheme has been composed, on the basis of which a new computational mathematical model has been developed for the plane-parallel motion of the asymmetric top harvester in the horizontal plane on the assumption that the connection between the wheeled tractor and the rear-trailed top harvester is made in the form of a cylindrical hinge joint. Using the results of mathematical modelling, the system of linear second-order differential equations that determines the transverse movement of the centre of mass of the aggregating wheeled tractor and the rotation of its longitudinal symmetry axis by a certain angle about the said centre of mass as well as the angle of deviation of the rear-trailed asymmetric top harvester from the longitudinal symmetry axis of the tractor at an arbitrary instant of time has been obtained. The solving of the obtained system of differential equations provides for determining the stability and controllability of the motion performed by the asymmetric machine-tractor unit, when it performs the technological process of harvesting sugar beet tops.
Winter wheat leaf blotches development depending on fungicide treatment and nitrogen level in two contrasting years
(Estonian University of Life Sciences, 2021) Švarta, A.; Bimšteine, G.; Gaile, Z.; Kaņeps, J.; Plūduma-Pauniņa, I.
Tan spot (caused by Pyrenophora tritici-repentis) and Septoria tritici blotch (caused by Zymoseptoria tritici) are the most widespread winter wheat leaf diseases in Latvia. The aim of the present research was to clarify the development of leaf blotches on winter wheat depending on fungicide treatment schemes under four nitrogen rates. A two-factorial trial was conducted at the Research and Study farm “Pēterlauki” (Latvia) of Latvia University of Life Sciences and Technologies. For this study, data from the 2018/2019 and 2019/2020 growing seasons was used. Four schemes of fungicide application and an untreated variant, as well as four nitrogen rates (N120, N150, N180, and N210 kg ha-1 ) were used. The total disease impact during the vegetation period was estimated by calculating the area under the disease progress curve (AUDPC). The severity of leaf blotches in winter wheat leaves differed significantly during both vegetation seasons. Tan spot was the dominant disease in 2019 (18.7% in untreated variant). The development of tan spot was reduced by fungicide treatment; however, only in 2019, the influence of fungicide was significant. Septoria tritici blotch was the dominant disease in 2020 (11.4% in untreated variant), and its development was decreased by fungicides. Nitrogen fertilizer rate had no significant effect on the development of Septoria tritici blotches. Yield harvested in 2020 were significantly higher than those in 2019 (on average 5.23 t ha-1 in 2019, 8.40 t ha-1 in 2020). The using of fungicides provided significant increase of yield but there were no significant differences among fungicide treatment schemes.
Development of an algorithm for assessing canopy volumes with terrestrial LiDAR to implement precision spraying in vineyards
(Estonian University of Life Sciences, 2022) Pagliai, A.; Sarri, D.; Lisci, R.; Lombardo, S.; Vieri, M.; Perna, C.; Cencini, G.; De Pascale, V.; Ferraz, G. Araújo E. Silva
Precision spraying is one of the techniques for the reduction of pesticides use and it can help achieve the new European Green Deal standards. The aim of such technique is to apply the right amount of pesticides according to the target characteristics. The precision spraying implementation requires target volume assessment, which can be carried out by LiDAR sensors. Such technique requires complex and time-consuming procedures of canopy characteristics computing through post-processing points cloud reconstruction. The present work aimed to develop and test an algorithm through the use of a tractor-coupled with terrestrial LiDAR and GNSS technology in order to simplify the process. With the aim to evaluate the algorithm the LiDAR-based volume was correlated with two manual measurements of canopy volume (Tree Row Volume and Point Net Cloud). The results showed good correlations between manual and LiDAR measures both for total canopy volumes (R 2 = 0.67 and 0.56) and for partial canopy volume (R 2 = 0.74). In conclusion, although the LiDAR-based algorithm works in automatic mode, the canopy volumes approximation seems acceptable to estimate the canopy volumes, with the advantages of a swifter procedure and less laborious post-processing computations.

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