Trellis System Research Articles

Molecular verification of commercialized Neoseiulus californicus (McGregor) settlement before spider mite appearance in a Japanese pear orchard

A report of our earlier study described a phytoseiid mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) release system using a moisturized sheltered sachet for spider mite control. For the present study, we installed the predator release systems on 43 out of 71 trees in a Japanese pear orchard to survey the dispersal of N. californicus released from the predator release system. In the orchard, Japanese pear trees were trained on the overhead horizontal trellis system. Consequently, the trees were mutually connected through the trellis training system. We collected phytoseiid mites on the tree leaves and were subjected to PCR to examine their species composition. Results demonstrated that N. californicus were 62.37% of the total of 3,247 phytoseiid mites collected. Using microsatellite markers, commercialized N. californicus that had been released from the predator release systems were discriminated from indigenous N. californicus. Results demonstrated that phytoseiid mites consisting mainly of the commercialized N. californicus occurred one week earlier in trees with the predator release systems. Results also demonstrated that the commercialized N. californicus dispersal occurred mainly in trees installed with the predator release systems.

Effects of cane- and spur-retained node numbers on the pre-flowering vegetative growth of cane-pruned Sauvignon blanc

In established vineyards, node number retention at winter pruning is the first step to achieving and maintaining vine balance. Balanced vines exhibit timely and quasi-uniform 100 percent budburst. To understand how vine capacity and balance are expressed before flowering, mature Sauvignon blanc vines were pruned according to a 5 [total node numbers on canes: 10, 20, 30, 40, 50] x 3 [total node numbers on spurs: 1, 2, 3] factorial design in one site, and in two other sites according to a 5 [total node numbers on canes: 10, 20, 30, 40, 50] x 2 [total node numbers on spurs: 1, 2] factorial design. Two spurs of one, two or three nodes each were retained on either side of the vine. The number of canes laid down per vine was one, two, three and four canes each of 10 nodes for the 10-, 20-, 30- and 40-node treatments, and four canes averaging 12.5 nodes for the 50-node treatment. The budburst percentage was calculated on the whole vine, canes, and spurs. Blind nodes, count shoots, non-count shoots and double shoots were counted and mapped along canes and spurs. Many non-count shoots were measured on the vine head of 10-node vines (29.5 ± 3.0 shoots, p < 0.001), compared to 50-node vines (2.8 ± 1.9 shoots, p < 0.001). 50-node vines had an overall budburst of 100 %, despite having the highest number of blind nodes (7.6 ± 0.3 nodes, p < 0.001). These were mainly located at the canes’ proximal sections relative to the vine head and were likely caused by correlative inhibition and primary bud necrosis. Cane budburst provided a more accurate assessment of the vine response to node loading than vine budburst. The number of double shoots was not associated with the vine node load, as they appeared on both low-node and high-node vines. Three-node spurs developed more blind nodes than one-node and two-node spurs (p < 0.001). Based on the findings of this research, we recommend a composite metric (cane percent budburst, cane blind node count and head shoot count) to assess vine capacity and balance between budburst and flowering, and the practice of retaining one- or two-node spurs at cane pruning is also justified.

Fruit Cracking in Pears: Its Cause and Management—A Review

Pears (Pyrus (Rosaceae, Pyrinae) are among the oldest plants cultivated by humans and the second most widely grown fruit worldwide, after apples. They are commercially important fruit trees; over the last few decades, global area, production, and exports have massively increased. However, fruit cracking at an early stage or at maturity is a severe physiological disorder, causing significant economic losses to pear growers. Fruit cracking may be associated with inadequate irrigation, environmental factors, and nutritional deficiencies, particularly those involving B, Ca, Zn, and potash. Fruits can crack during growth and development due to the abrupt temperature changes between day and night, water imbalances, sun exposure, trellis systems, and the color of the fruit packaging. Cracking is more pronounced when the fruit has reached maturity, and no single factor is known to effectively prevent its occurrence. Although fruit cracking poses the risk of great economic losses, research on its cause and management in pears is limited as compared to other fruit crops. Therefore, examining the occurrence of pear fruit cracking in relation to cultivar genetics, fruit composition and quality, the water levels of the soil and water uptake by plants, and the role of micronutrients and plant growth regulators will aid in the development of strategies to reduce fruit cracking in pears. This review briefly summarizes the causes of fruit cracking in pears and possible control strategies.

Adapting wine grape production to climate change through canopy architecture manipulation and irrigation in warm climates.

Grape growing regions are facing constant warming of the growing season temperature as well as limitations on ground water pumping used for irrigating to overcome water deficits. Trellis systems are utilized to optimize grapevine production, physiology, and berry chemistry. This study aimed to compare 6 trellis systems with 3 levels of applied water amounts based on different replacements of crop evapotranspiration (ETc) in two consecutive seasons. The treatments included a vertical shoot position (VSP), two modified VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a Guyot pruned VSP (GY) combined with 25%, 50%, and 100% ETc water replacement. The SH had greater yields, whereas HQ was slower to reach full production potential. At harvest in both years, the accumulation of anthocyanin derivatives was enhanced in SH, whereas VSPs decreased them. As crown porosity increased (mostly VSPs), berry flavonol concentration and likewise molar % of quercetin in berries increased. Conversely, as leaf area increased, total flavonol concentration and molar % of quercetin decreased, indicating a preferential arrangement of leaf area along the canopy for overexposure of grape berry with VSP types. The irrigation treatments revealed linear trends for components of yield, where greater applied water resulted in larger berry size and likewise greater yield. 25% ETc was able to increase berry anthocyanin and flavonol concentrations. Overall, this study evidenced the efficiency of trellis systems for optimizing production and berry composition in Californian climate, also, the feasibility of using flavonols as the indicator of canopy architecture.

Sheep in the Vineyard: Suitability of Different Breeds and Potential Breeding Objectives.

Simple SummaryThere is a large number of sheep breeds worldwide. Today, many of them are endangered, because there are very little market demands for the majority of breeds. The integration of sheep in viticultural systems offers a promising option to put sheep and unique breed characteristics in value. However, it is unknown which characteristics and breeds are best suited for this purpose. The lack of information leads to problems in the implementation of this so-called new integrated crop-livestock system. In our research, we addressed this challenge. We studied 26 breeds and tested their suitability for integration into common vineyards of Central Europe. Two breeds fulfill the most important requirement. Southdown and Shropshire, for the latter especially, the sheep of the shorter legged Danish type seem to be unable to stand on two legs. Their muzzle heights stay within a tolerable range without harming the foliage area of vines. Therefore, adult animals of both breeds seem suitable to take over important viticultural tasks during the growing season. A third breed, the Ouessant sheep, is suitable with some limitations.Protecting a breed of sheep is simple when there is demand for its breed traits, but new market options are often hard to find. In general, grazing sheep are able to take over some viticultural work. Here, we address a new and promising integrated crop-livestock system that involves the integration of sheep in the vineyard during the growing season. Using sheep in a vineyard entails opportunities but also risks, such as the current lack of information, specifically in relation to breed traits. In our survey, we evaluated 26 breeds for their suitability for grazing as long as possible in Central European vineyards during the growing season. First, the breed traits required were identified. Then, 94 flock book breeders were interviewed about specific breed traits. The height of a sheep’s muzzle is particularly important for assessing the suitability of a breed, as it defines the potential impact on the foliage area during the growing season. To determine the height of the muzzle, 179 flock book animals were measured. We found that the most important breeding objective for a new breed of sheep is the inability to stand on two legs. Adult animals of the breed Shropshire, and among these especially the shorter-legged Danish type, and Southdown, show a widespread inability to stand on two legs. Ouessant sheep are able to do so, yet are suitable with some limitations. Due to their extraordinarily small size, their reach is limited, as is their grazing performance. Thus, three of the 26 breeds studied here seem suitable for use in the most widespread vine training systems of Central Europe during the growing season. Targeted breeding could further improve the suitability of sheep for viticulture. Our findings could help to protect breeds and breed traits.

Yield and Physiological Response of Autumn King and Scarlet Royal Table Grapes to Cane and Spur Pruning Systems

The type of training system affects vine growth and productivity; however, there is a lack of knowledge on the suitability of pruning systems for some recently introduced (Vitis vinifera L.) cultivars. In this study, we provide the growers with science-based information about the response of two table grape variates to cane and spur-pruning systems to develop the best cultural practices. In 2013, a vineyard was established at Kearney Agriculture Research Center, Parlier, California using “Autumn King” and “Scarlet Royal” table grapes (Vitis vinifera L.) grafted on Freedom rootstock. The performance of the three-year-old vines was assessed under two pruning systems, Quadrilateral cordon training (spur-pruning) and Head training (cane pruning). Data from the 2016 and 2017 seasons showed no significant differences in leaf area, chlorophyll content, Normalized Difference Vegetation Index (NDVI), and pruning weight between the two pruning systems in both cultivars. In both seasons, marketable yield did not vary between the two pruning systems in the Scarlet Royal. However, Autumn King marketable yield was significantly reduced when using the Quadrilateral cordon training (spur-pruning). Petioles nutrient analysis at bloom showed a non-significant increase in nitrate content in the cane pruned vines of both varieties. No significant difference was observed in cluster weight, berry physical, or chemical composition. It seems that both training systems could be used for Scarlet Royal. However, the cane pruning system in Autumn King produced higher yield without affecting cluster and berry quality. The different responses of the two varieties could be due to the genetic background and growth behavior. Our data confirmed the notion that the different responses to the training methods by various grape varieties may involve the genetic background, growth behavior, as well as nutrient uptake and usage by the vines. Establishing the proper training system for each grape variety is essential.

Growth, Development and Yield of Golden Currant (Ribes Aureum Pursh.) Depending on Cultivation System

Abstract Although golden currant has been grown in Latvia for several decades, mainly as ornamental plant, there is little experience on the most suitable cultivation systems for berry production. Two cultivars of golden currant — ‘Laila’ and ‘Uzbekistanskaya Krupnoplodnaya’, were planted in 2017 in two cultivation systems — vertical trellis and shrub form and assessed in the first two seasons with harvest. In addition, plots with and without organic mulch were established in the shrub system. The aim of the study was to investigate the growth, development and yield of golden currant depending on the cultivation system. All plants bloomed abundantly and practically at the same time in both years, while no significant differences were found between cultivation systems and cultivars. The annual growth of shoots in 2020 was significantly affected by the cultivation system — on average 0.66 m in the trellis system, 0.41 m in the shrub system in mulched plots, and 0.43 m in unmulched plots. Cultivar ‘Laila’ tended to produce longer shoots (average 0.51 m) than the ‘Uzbekistanskaya Krupnoplodnaya’ (average 0.47 m). The yield was low because of poor fruit set and did not significantly differ between cultivar and cultivation systems, though cultivar ‘Laila’ and shrub systems still had higher yields.

Effect of over crop and reduced yield by cluster thinning on phenolic and volatile compounds of grapes and wines of 'Sangiovese' trained to Tendone.

'Sangiovese' (Vitis vinifera L.) is a well-known Italian wine grape utilized for producing the prestigious Chianti Classico brand. Here, 'Sangiovese' is generally trained to a vertical training system, with an imposed crop level of around 3-5 kg per vine to preserve grape quality. Tendone comprises a horizontal trellis system, largely diffused in Mediterranean Countries for table grape production, and is adopted to achieve a high yield and to preserve grapes, by means of its canopy architecture, from excessive solar radiation, which in turn affects the organoleptic aspects of grapes and wines. The present study aimed to evaluate, in terms of phenolic and volatile compounds of grape and wines, 'Sangiovese' trained to Tendone, as affected by two crop levels, namely very high and reduced yields. Reduced yield (18.39 kg per vine) by cluster thinning still appeared to provide a considerable yield and quality of grapes and wines. Thinning increased pH, tartaric acid content, flavonoids, anthocyanins, total polyphenols and proanthocyanins, and total free and bound aroma compounds, without affecting soluble solids and titratable acidity of grapes. As regards wines, reduced yield increased pH, tartaric and malic acids and dry reduced extract, flavonoids, anthocyanins, total polyphenols and proanthocyanins, and, finally, the color intensity of wines. The present study highlights that Tendone training systems, combined with 40% of cluster thinning, allows a high yield to be reached, allowing, at the same time, a very interesting quality of grapes, making it possible to produce qualitative wines. © 2022 Society of Chemical Industry.

Comparing Different Methods for Pruning Pitaya (Hylocereus undatus)

Recently there have been new trends in global consumption toward fresh foods that are sources of healthy bioactive compounds, as is the case with pitaya. However, pitaya cultivation is a relatively recent phenomenon and little is known about its management. The objective of this work is to determine the most appropriate annual fruiting pruning method for pitaya in order to obtain a regular annual yield of quality fruit and an intense shoot renewal that guarantee future production. This study compared the response of Hylocereus undatus to spur, cane, and combined pruning. As control plants, we left some plants where only sanitary pruning was performed. The results indicate that spur pruning greatly reduced flowering (seven times less than controls) and did not promote intense vegetative growth. Cane pruning, on the contrary, allowed greater flowering which is compatible with a higher number of new shoots (8% more than controls). The vigor of the new shoots was equal in all treatments. Fruit size and quality did not differ either among treatments. Spur pruning only seems applicable as a rejuvenation pruning. Combined pruning gave an intermediate response and seems of no interest given the good shoot renewal provided by cane pruning. Performing sanitary pruning alone may be an interesting option, but only in the first years of cultivation.

The Effect of Spur Position and Pruning Severity on Shoot Development

Adjusting yearly pruning severity is a common vineyard management practice employed to manipulate vegetative and reproductive growth in grapevines. Although the effects of pruning on total vegetative growth are well documented, there is little research on the effects of adjusting shoots meter−1 via dormant season pruning on addressing mid-cordon shoot weakness and developmental delays. Cordon-trained, spur-pruned vines are thought, by many growers, to be especially prone to weaker positions and delayed development at mid-cordon positions. This phenomenon is also thought to become more exaggerated as the vine ages. Therefore, the effects of shoot density manipulation, implemented via dormant pruning practices, to homogenize shoot and cluster development along the length of the cordon were examined. In this research, Cabernet Sauvignon grapevines were pruned to either 5.5 shoots meter−1 (5.5) or 11.1 shoots meter−1 (11.1). To control for variations in light interception into the fruiting zone, a control of 11.1 shoots meter−1 with sensor guided leaf thinning (11.1LT) was implemented at full berry set to match the canopy light of the 5.5 shoots meter−1 treatment. It was found that individual shoot growth and yield were directly impacted by manipulation of pruning severity. Shoot growth response varied primarily by growing season, including shoot length and internode length. Yield components were significantly lower in the 5.5 treatment during the first two years of the study but were not significantly different during the last year of the study. The 5.5 treatment resulted in the highest pH and total soluble solids at harvest in 2016 and 2017.

Kinematic-Based Multi-Objective Design Optimization of a Grapevine Pruning Robotic Manipulator

Annual cane pruning of grape vineyards is a time-consuming and labor-intensive job, but no mechanized or automatic way has been developed to do it yet. Robotic pruning can be a perfect alternative to human labor. This article proposes a systematic seven-stage procedure to design a kinematically optimized manipulator, named ‘Prubot’, to manage vineyards’ cane pruning. The manipulator structure was chosen, resulting in a 7R (Revolute) manipulator with a spherical shoulder and wrist. To obtain the design constraints, the manipulator task space was modeled. The robot’s second and third link lengths were determined by optimizing the global translational version of the measure of manipulability and the measure of isotropy of the manipulator arm section. Finally, simulations confirmed the appropriateness of the manipulator workspace. Furthermore, sampling-based path planning simulations were carried out to evaluate the manipulator’s kinematic performance. Results illustrated the impressive kinematic performance of the robot in terms of path planning success rate (≅100%). The simulations also suggest that among the eight single-query sampling-based path planning algorithms used in the simulations, Lazy RRT and KPIECE are the best (≤5 s & ~100%) and worst ≥5 s &≤25% path planning algorithms for such a robot in terms of computation time and success rate, respectively. The procedure proposed in this paper offers a foundation for the kinematic and task-based design of a cane pruning manipulator. It could be promisingly used for designing similar agricultural manipulators.

Effect of early cane pruning on yield components, grape composition, carbohydrates storage and phenology in <i>Vitis vinifera</i> L. cv. Merlot

Dormant cane pruning has a great impact on vineyard management both in terms of labour costs and the time required to complete this field operation in the absence of mechanisation. In this study, we investigated over three seasons the influence of five pruning dates on yield components, grape composition, phenology and carbohydrate reserves in the variety Merlot, grown in a warm climate area. Pruning was conducted soon after harvest, at the end of leaf fall, two bud dormancy stages and vine bleeding. Early pruning, carried out a few days after the grape harvest, did not significantly affect vine productivity or grape composition in the next season compared to full winter pruning. Similarly, non-structural carbohydrate concentration in trunk and roots showed no difference just before budburst, no matter the timing of pruning. Late winter pruning at vine bleeding slightly postponed budburst and flowering; it also delayed veraison in one out of two years of observation without affecting grape maturity. Our findings suggested that, in a warm-climate area where leaf fall occurs within a ten-week period after harvest, early pruning had no detrimental effects on reserve accumulation in storage organs and, therefore, in vine yield and grape composition in the next harvest, thus allowing viticulturists to operate winter pruning over an extended interval of time.

Aerial images to monitor grapevine vegetative growth

Images obtained by Remotely Piloted Aircraft (RPA) used to monitor the crop can help evaluate leaf mass, plant formation, and plant population. In this context, the objectives of this study were to analyze plant growth in a grapevine crop trained in the trellis system, detect failures and determine the plant covered area using images obtained by RPA. The flight was parameterized with frontal overlap of 75%, lateral overlap of 70%, Ground Sample Distance (GSD) of 60 m, and flight speed of 5 m.s-1, using a sensor in the visible range. Processed images showed a stand 3% smaller than projected, an area covered by vine branches occupying 60.8%, undergrowth and invasives represented 5.3%, and exposed soil 33.9%. Vines were identified in the vegetation indices as green points, invasive plants as yellow points, and exposed soil as red points. Image processing obtained with RPA allowed identification of plants in various stages of development, with predominance of vines in the formation process. It was possible to identify the plants and quantify the leaf mass using the MPRI vegetation index, as well as to differentiate exposed soil from plant material. It was also observed that the plot had an incomplete stand at the time the flight was performed.

Performance Evaluation of Coccinia (Coccinia grandis L. Voigt) under Different Training Systems and Growing Environments

The present investigation was conducted during 2021-2022 at the Department of Vegetable Science, Horticultural College and Research institute, Tamil Nadu Agricultural University (TNAU) to examine the performance of coccinia in different growing environments and training systems. The experiment was laid out in Factorial randomized block design (FRBD) with three replications. The treatment combinations comprised of two growing environments viz, open field (G1) and polyhouse (G2) with four training systems viz., Trellis system (T1), Vertical system (T2), Fish net (T3) and Pandal system (T4). Among these treatments, vertical training system and polyhouse cultivation was found to be superior for growth and yield attributing traits. In the vertical system of training the fruit yield was superior in polyhouse with the yield of 154.76 t/ha/year and 80.49 t/ha/year in open field. The interaction effect of polyhouse environment and vertical training (G2T2) was revealed by the highest number of fruits per vine (17.92), fruit yield/plant (5.15/kg), annual fruit yield (61.90 kg/plant) recorded in plants trained by vertical system. From the results it was concluded that, highest productivity in coccinia could be obtained from Polyhouse condition (G2) with the adoption of vertical system of training (T2).

Design of a lightweight robotic arm for kiwifruit pollination

Robotic simulation is an important method for verifying robot design parameters and the feasibility of various schemes. We simulated and analysed the effectiveness of the design parameters of a robotic arm for kiwifruit pollination and verified the rationality of the robotic arm’s movement during pollination. First, the basic parameters and working space of the robotic arm for kiwifruit pollination were identified based on a trellis system that supports kiwifruit vines. MATLAB software was employed for the simulation to prove that the working space of the lightweight robotic arm for pollination can satisfy the operating requirements. Appropriate joint motors were selected based on the maximum theoretical torque on each joint of the robotic arm obtained through the analysis. SolidWorks software was used to verify the strength of the robotic arm materials and joint connectors, and the operating environment of the robotic arm and MATLAB software were applied to simulate and analyse the feasibility of trajectory planning for pollination. Based on the simulation results, we built a prototype of the robotic arm and a motion control system. The experiment indicated that the maximum operating speed of this lightweight pollination robotic arm was ωmax = 0.105 rad/s, the pollination success rate was 85%, the average pollination time of a single flower was 5 s, and the pollination efficiency was 78 min/mu, which was significantly higher than the 86 min/mu of artificial brush pollination. The lightweight pollination robotic arm satisfied the automatic operation requirements of kiwifruit pollination.

3D Assessment of Vine Training Systems Derived from Ground-Based RGB-D Imagery

In the field of computer vision, 3D reconstruction of crops plays a crucially important role in agriculture. On-ground assessment of geometrical features of vineyards is of vital importance to generate valuable information that enables producers to take the optimum actions in terms of agricultural management. A training system of vines (Vitis vinifera L.), which involves pruning and a trellis system, results in a particular vine architecture, which is vital throughout the phenological stages. Pruning is required to maintain the vine’s health and to keep its productivity under control. The creation of 3D models of vineshoots is of crucial importance for management planning. Volume and structural information can improve pruning systems, which can increase crop yield and improve crop management. In this experiment, an RGB-D camera system, namely Kinect v2, was used to reconstruct 3D vine models, which were used to determine shoot volume on eight differentiated vineyard training systems: Lyre, GDC (Geneva Double Curtain), Y-Trellis, Pergola, Single Curtain, Smart Dyson, VSP (Vertical Shoot Positioned), and the head-trained Gobelet. The results were compared with dry biomass ground truth-values. Dense point clouds had a substantial impact on the connection between the actual biomass measurements in four of the training systems (Pergola, Curtain, Smart Dyson and VSP). For the comparison of actual dry biomass and RGB-D volume and its associated 3D points, strong linear fits were obtained. Significant coefficients of determination (R2 = 0.72 to R2 = 0.88) were observed according to the number of points connected to each training system separately, and the results revealed good correlations with actual biomass and volume values. When comparing RGB-D volume to weight, Pearson’s correlation coefficient increased to 0.92. The results reveal that the RGB-D approach is also suitable for shoot reconstruction. The research proved how an inexpensive optical sensor can be employed for rapid and reproducible 3D reconstruction of vine vegetation that can improve cultural practices such as pruning, canopy management and harvest.

Volatile Composition of Sparkling Wines of cv. Chardonnay Cultivated under Different Training Systems in Serra da Mantiqueira (Brazil).

The grapevine is a climbing plant and allows for the manipulation of vegetative canopies to change the microclimate and exposure of leaves and clusters to solar radiation, affecting the primary and secondary metabolisms of plants. Thus, this work aimed to evaluate how the lyre and Geneva double-curtain (GDC) training systems could contribute to the volatile composition of sparkling wines in replicates of vinifications carried out in the Serra da Mantiqueira (Brazil) in two consecutive summer harvests (2017 and 2018). Fifty-four free volatile compounds were identified by HS-SPME/GC-MS in the wines in both systems and vintages. Multivariate analysis differentiated the vintages in component 1 (22.7%) and the training systems in component 2 (7.1%). The crops were differentiated by aldehydes in 2017 and in 2018 by isoamyl acetate ester, probably derived from the amino acid leucine, the season having been more humid, with lower temperatures and less radiation. For the training systems, besides the alcohol compounds, the GDC was differentiated by the terpenoid compounds geranylacetone and β-damascenone, which may contribute more pleasant aromas to sparkling wines. This work promotes additional research and enables winegrowers, through the management of their vineyards, to achieve sparkling wines with different volatile compositions.

Characterising retained dormant shoot attributes to support automated cane pruning onVitis viniferaL. cv. Sauvignon Blanc

Background and Aims The shortage of skilled pruners portends automation as an alternative. To train an Artificial Intelligence (AI) system in cane pruning, the attributes of grapevine dormant shoots were characterised. Methods and Results Eight attributes of dormant shoots, diameter, length, vertical and horizontal distance, node number, internode length, origin and position relative to bottom fruiting wire, were measured prior to and after pruning. Vine canopies were modified according to a 5 [total node numbers on canes: 10, 20, 30, 40, 50] × 3 [total node numbers on spurs: 1, 2, 3] factorial design. Compared to non-retained dormant shoots, retained dormant shoots were thicker (9.2 ± 0.07 mm), longer (104.7 ± 0.93 cm), close to the vine trunk (11.4 ± 0.65 cm) and below the bottom fruiting wire (83.2 ± 0.54 cm). Spurs had the shortest horizontal (9.8 ± 0.93 cm) and vertical (77.8 ± 0.7 cm) distance, originating from the vine head, base nodes and first nodes of old canes and old spurs. Modifying the vine canopy via increased node numbers had a significant effect on all retained dormant shoot attributes (P < 0.05) except on the position relative to the bottom fruiting wire. Conclusions Cane pruning in commercial vineyards is consistent and follows rules based on viticulture knowledge. Retained, non-retained dormant shoots, canes and spurs exhibit distinct attributes useful in quantifying, assessing and modelling cane pruning. Significance of the Study Data and knowledge from the research are currently being used in modelling and training AI cane-pruning algorithms.

The modernization of traditional vineyards into intensive trellis systems reduces the species richness and abundance of reptiles

Aim of the study: Traditional vineyards have, in the last few decades, been transformed into trellis systems, but little research has been carried out into the consequences as regards biodiversity. We compared the abundance and species richness of reptiles in conventional-traditional vineyards and trellis vineyards. Area of study: The study was conducted in a wine appellation area of origin denominated as Montilla-Moriles, Southern Spain. Material and methods: Reptile’s species richness and abundance were estimated by walking transects in 24 different vineyards (12 trellis and 12 traditional vineyards) in four consecutive years. Main results: The results showed an extremely low abundance in both management systems, since no reptiles were recorded in 43.1% of the transects. However, there was a greater abundance and diversity of reptiles in the traditional vineyards than in the trellis vineyards, with 7 vs. 3 species being found in traditional and trellis vineyards, respectively. Research highlights: The lack of refuge in trellis vineyards owing to the vertical growth of plants, whose branches grow higher from the ground, is probably the main cause of the lower abundance and species richness found in trellis systems, since both types of vineyard had bare ground owing to ploughing and the application of herbicides. Since the transformation of traditional vineyards into those with trellis systems is often subsidized, this modernization should be accompanied by certain agri-environmental measures (e.g., cover crops, artificial refuges or natural hedges) in order to compensate for the associated negative effects.

3D Distance Filter for the Autonomous Navigation of UAVs in Agricultural Scenarios

In precision agriculture, remote sensing is an essential phase in assessing crop status and variability when considering both the spatial and the temporal dimensions. To this aim, the use of unmanned aerial vehicles (UAVs) is growing in popularity, allowing for the autonomous performance of a variety of in-field tasks which are not limited to scouting or monitoring. To enable autonomous navigation, however, a crucial capability lies in accurately locating the vehicle within the surrounding environment. This task becomes challenging in agricultural scenarios where the crops and/or the adopted trellis systems can negatively affect GPS signal reception and localisation reliability. A viable solution to this problem can be the exploitation of high-accuracy 3D maps, which provide important data regarding crop morphology, as an additional input of the UAVs’ localisation system. However, the management of such big data may be difficult in real-time applications. In this paper, an innovative 3D sensor fusion approach is proposed, which combines the data provided by onboard proprioceptive (i.e., GPS and IMU) and exteroceptive (i.e., ultrasound) sensors with the information provided by a georeferenced 3D low-complexity map. In particular, the parallel-cuts ellipsoid method is used to merge the data from the distance sensors and the 3D map. Then, the improved estimation of the UAV location is fused with the data provided by the GPS and IMU sensors, using a Kalman-based filtering scheme. The simulation results prove the efficacy of the proposed navigation approach when applied to a quadrotor that autonomously navigates between vine rows.