Orchard Crops Research Articles

Grapevine, stone fruit, and tree nut crop response to simulated tetflupyrolimet drift

Abstract Off-target rice herbicide drift is historically a concern in California, where susceptible crops such as orchards and vineyards are nearby. Tetflupyrolimet is a potent inhibitor of dihydroorotate dehydrogenase which provides excellent grass weed control in rice cropping systems. In efforts to steward tetflupyrolimet before its registration in California, this research was conducted to compare the onset of foliar symptoms from tetflupyrolimet applications onto almond, grapevine, peach, pistachio, plum, and walnut. Tetflupyrolimet was applied to these tree and vine crops at fractional rates of 1/200×, 1/100×, 1/33×, and 1/10× of the 125 g ai ha–1 rice use rate. Almond, pistachio, and walnut trees also received the 1× of the rice use rate. Tetflupyrolimet treatments were applied on one side of 3- to 4-yr-old almond, peach, pistachio, plum, and walnut trees and on one side of 25- to 26-yr-old grapevines in 2022 and 2023. Visible injury ratings were carried out weekly to assess symptomology throughout the growing seasons and at leaf out the following springs. Tree trunk diameter was recorded before and after herbicide applications. No injury was observed on any crops tested, regardless of the tetflupyrolimet application rate. In all orchard crops, tree trunk diameter was not affected by tetflupyrolimet treatments. Likewise, grape yield was not reduced even at the 1/10× tetflupyrolimet fractional rate. Since no injury symptoms were recorded, this research suggested that tetflupyrolimet can be safely used at nearby rice fields and might be a target for future registration consideration in orchard and vineyard crops.

Organic Management and Intercropping of Fruit Perennials Increase Soil Microbial Diversity and Activity in Arid Zone Orchard Cropping Systems

Organic farming encourages soil management practices that can improve soil health and fertility by increasing soil organic matter inputs and system sustainability. This study evaluated the effect of three years of continuous organic farming and intercropping orchard treatments on soil microbial diversity, microbial enumeration, respiration, soil fertility and fruit yields. Organic management resulted in higher soil organic matter content, Olsen P, and water holding capacity, but did not affect soil pH, electrical conductivity (EC), K, or Na levels. Growth parameters measured on all fruit trees were not significantly different among treatments. The enumeration of bacteria was significantly higher in organic plots when compared to conventionally managed plots. Soil respiration and substrate-induced respiration were significantly higher in the organic diverse plots in comparison to both conventional systems. The genomic analysis of prokaryotes (16S rRNA) and eukaryotes/fungi (ITS) revealed a significantly higher number of taxa, Shannon H index, and Equitability index in the organic systems for both prokaryotes and eukaryotes, in comparison to conventional farming, all of which are indicators of system sustainability. The relative abundance of Operational Taxonomic Units (OTUs) previously reported as diazotrophs, denitrifiers, or involved in the sulfur cycle, as well as Arbuscular Mychorrizae Fungi (AMF)/glomeromycotan, were highest in the organically managed soils than in the conventional plots. A multivariate correlation network clustering revealed that the microbial communities within the organic and conventional soils had strong dissimilarities regarding soil microbial niches. Our work provides evidence that organic management can be used for increasing soil microbial diversity and soil health, leading to higher levels of sustainability in fruit orchard systems.

Future semiochemical control of codling moth, Cydia pomonella

Codling moth (CM), Cydia pomonella, is a significant pest of apple (Malus domestica) and other orchard crops worldwide, posing challenges due to the decrease in registered insecticides, rising resistance, and a changing climate. The pest exhibits a strong resistance capacity to both synthetic and natural insecticides, while shifting seasonal temperatures disrupt the reliability of phenology-temperature models for predicting targeted control strategies. Alternative control strategies are necessary to future-proof control of this pest. Current control methods primarily rely on chemical insecticide sprays or granulosis virus applications during egg hatching. This review focuses explicitly on semiochemical-based manipulation of CM adults and larvae for control in orchards. Topics covered include the role of semiochemicals in integrated pest management, area-wide control, mating disruption, female attractants, larval kairomones, and incorporation into monitoring and control strategies. The potential of CM repellents in a push–pull strategy is also discussed. Primary sources for identifying relevant literature included GoogleScholar and ResearchGate, with a focus on papers published since 2013 but also include relevant papers from 2003. Nine review papers and 119 papers were reviewed. The review emphasizes that effective control necessitates an area-wide approach targeting all life stages (eggs, larvae, pupae, and adults). Comprehensive monitoring is crucial for identifying CM “hot-spots” and enhancing targeted interventions. Growers must consider landscape context when designing control programs. Lastly, recommendations are provided for future research and CM management strategies. There are opportunities to explore and exploit female kairomone attractants and repellents in control strategies and modify monitoring traps to be more attractive and autonomous.

Quantitative trait loci for bearing habit in a ‘Sparrow’ × ‘Schessler’ Juglans nigra mapping population

Eastern black walnut, Juglans nigra L., is an economically important tree species valued for its high-quality timber and edible nuts. A regional industry for the species’ nut and kernel products resides in Missouri, where over 9 million kg of hulled in-shell nuts are purchased in masting years. The crop is primarily based upon nuts harvested from wild trees, placing a ceiling on nut volume and quality (e.g. small nut size, dark pellicle color, and 10–14% kernel by weight). Orchards of named cultivars, like ‘Kwik Krop’ and ‘Sparrow’, supply up to 22,000 kg of nuts with a higher kernel percentage (> 26%) and improved quality. Such cultivars often represent chance wild or on-farm seedlings, clonally propagated since the late 1800’s by enthusiasts. Today, continued improvement of eastern black walnut as an orchard crop is limited by a long generation time, delayed expression of important traits, and space requirements – creating a strong need for marker-trait association studies that inform progeny selection. The first linkage map for J. nigra was recently created using the ‘Sparrow’ × ‘Schessler’ F1 population and loci for phenology traits discovered. The objective of this study is to utilize these genetic resources to detect quantitative trait loci (QTL) and report associated DNA markers for the spur-bearing habit, which promotes precocity and high yield. Using single-year data from the 11-year-old population, we observe that segregation for the spur-bearing habit appears to be recessive and multigenic. Three QTLs (p > 0.99) were identified on linkage group (LG) 8, LG11, and LG16 that explain 7.2%, 8.7%, and 10% of trait variation, respectively. Regions between flanking DNA markers were 3.16 cM, 4.32 cM, and 9.69 cM, respectively. This study is the first to examine the genetic control of bearing habit and yield in eastern black walnut and informs breeders’ approach for their future genetic improvement.

Evaluation of Pyroxasulfone Crop Safety and Weed Control for California Tree Nut Orchards

Pyroxasulfone is a very long chain fatty acid (VLCFA) inhibitor (group 15) with potential for preemergence weed control in orchard crops and would be beneficial for reducing selection pressure for resistance to more commonly used herbicides, such as glyphosate. Pyroxasulfone is registered and widely used in corn and soybeans in the United States as a solo product and in several premix formulations. However, there is limited published information on the performance and safety of pyroxasulfone in tree nut orchard systems. To assess the potential fit for pyroxasulfone in this crop sector, a series of crop safety and weed control efficacy experiments were carried out in key California orchard crops and in fallow fields with common orchard weeds. The non-crop studies were conducted near Davis, CA, to evaluate winter annual weed control with pyroxasulfone in comparison with pendimethalin and indaziflam. In addition, an irrigation incorporation experiment was conducted in summer to evaluate the effects of incorporation timing on pyroxasulfone, pendimethalin, and indaziflam efficacy as a measure of relative stability. Orchard weed control experiments were conducted in spring in an almond orchard near Arbuckle, CA, and a walnut orchard near Davis, CA. The orchard experiments included pyroxasulfone, pendimethalin, and indaziflam in various rate combinations with glufosinate. To evaluate crop safety, 2-year experiments were conducted to evaluate repeated applications of above-label rates of pyroxasulfone at 1199 g·ha−1 and S-metolachlor at 14,010 g·ha−1 on 1- to 2-year-old almond, pistachio, and walnut trees near Davis. Pyroxasulfone performed similarly to commercial standards with up to 95% control of broadleaf and grass weeds with pyroxasulfone and indaziflam providing 96% to 100% control of annual bluegrass, and pyroxasulfone (293 g·ha−1) being the only herbicide to suppress (>70%) common lambsquarters at 60 days after treatment (DAT). Other weeds controlled by pyroxasulfone include swinecress, redroot pigweed, yellow nutsedge, and Italian ryegrass. No differences were found among treatments in the incorporation timing study indicating adequate stability on the soil surface under summer conditions. Crop injury was not observed in the established orchards or the young orchard studies and there were no treatment effects on tree trunk diameter of almond, pistachio, and walnut in the 2-year crop safety experiments. These results indicate a potential for pyroxasulfone in California tree nut orchard systems that would be an additional site of action and beneficial for management of herbicide-resistant weeds in these crops.

Osmia lignaria (Hymenoptera: Megachilidae) increase pollination of Washington sweet cherry and pear crops.

Apis mellifera Linnaeus (Hymenoptera: Apis), honey bees, are the most widely used managed crop pollinators. However, their high rental cost and uncertain availability for North American orchard crops have motivated growers to explore alternative pollination options. We examined whether adding solitary, spring-flying Osmia lignaria Say (Hymenoptera: Megachilidae), blue orchard bees, as co-pollinators with A. mellifera in Washington sweet cherry and pear orchards enhances fruit set and yield compared to the use of A. mellifera alone. We added managed O. lignaria to orchard sites where A. mellifera hives were already present. Fruit set, fruit yield, and O. lignaria reproduction at O. lignaria-supplemented sites were compared to nearby, paired sites pollinated only by A. mellifera (3 paired cherry and 3 paired pear sites). For both crops, the addition of O. lignaria significantly increased fruit set but did not yield at harvest. Microscopic inspection of pollen grains from O. lignaria nest cell provisions confirmed that O. lignaria primarily visited orchard flowers. Mean retention of O. lignaria in cherry orchards was slightly higher (65%) than O. lignaria retention reported in other orchard crops (30%-60%). However, retention in pear orchards was much lower (≤20%). These results show that supplementing hives with O. lignaria in Washington spring orchard crops can increase overall pollination, but that trees fail to bear developing fruit to maturity. The strategy of using co-pollinators, O. lignaria and A. mellifera, in US orchards may act as "pollination insurance" when A. mellifera hives are in low supply or when the weather is not amenable for A. mellifera flight during the bloom period.

Determining and Mapping Biomass Energy Potential from Agricultural Residues in Syria

Syria faces a problem of restricted access to fossil fuels due to limited resources. In this paper, the potential of biomass and the total heat value produced from agricultural residues for 32 agricultural crops has been studied. Data from the Syrian Ministry of Agriculture for the year 2016 were utilized to determine the total annual potential of field and orchard agricultural residues using the residue-to-product ratio. The study also examined the distribution of regions with the highest production of agricultural waste in the country. The research found that approximately 1.93 million tons of agricultural residues were produced, with 0.698 and 1.213 million tons for field and orchard crops, respectively. The most significant agricultural residues came from olive trees, wheat plants, and orange trees, accounting for 35%, 11%, and 10%, respectively. The possible heat value from field and orchard crops was 23,972 and 44,932 Btu, respectively. This quantity provides 17.6% of Syria's energy consumption. The provinces with the highest production of agricultural residues were Aleppo, Lattakia , and Tartus, with values of 12.35, 11.8, and 8.04 PJ, respectively. According to the study, agricultural residues in Syria have the potential to be a sustainable source for biomass.

Population monitoring and status evaluation of the new invasive pest, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), in various crop systems of Georgia (Sakartvelo)

Summary The spotted wing drosophila, Drosophila suzukii (Matsumura, 1931), population fluctuations and distribution were monitored in four susceptible crops (blueberry, strawberry, cherry, wine grapes) and five major agricultural regions of Georgia (Guria, Samegrelo, Imereti, Kartli and Kakheti) during the years 2021 and 2022 with the aim to study the population size and evaluate the pest status. Population monitoring was conducted in four locations of each studied region on a weekly basis from May to November using PHEROCON® SWD traps with PHEROCON® SWD PEEL-PAK™ Broad Spectrum Lures. The investigation indicated significant growth of population from 2021 to 2022 in most of the studied locations. Population increase was detected in all crop orchards except cherries. Τhe absence of alternative host plants at crop proximity was of critical importance to save the crop from pest invasion. The crop plant species did not have a significant impact on D. suzukii. Pest population was significantly larger in summer and autumn compared to spring, possibly influenced by the ripening of alternative crops such as blackberry and elderberry. The sex ratio between male and female individuals was almost 1:1 and remained consistent through the two-year study period and across regions. We consider that D. suzukii entered the country from the southwestern part and extended its distribution range towards the east. No strategies for D. suzukii control have been elaborated in Georgia so far. Sprays of effective pesticides based on pest monitoring as well as sanitation measures involving removal of alternative host plants and any crop residues from the field are necessary to avoid pest outbreak.

A Review of Orchard Robot Research

In modern agricultural production, orchards, as one of the important agricultural fields, are facing difficulties such as labor shortage, low production efficiency, and rising costs. To cope with these difficulties, orchard robots were introduced as an emerging technology. With the rapid development of robotics, artificial intelligence and machine learning, the application of intelligent robots in the agricultural field is becoming more and more mature. Advances in sensing technology, navigation technology, image recognition and other technologies have provided technical support for the research and application of orchard robots. Through the precise operation of orchard robots, precise management of orchard crops can be realized, including precise fertilization, pest and disease monitoring, directional irrigation, etc., so as to improve the yield and quality of orchards. This increases production efficiency, reduces costs, increases yields, and drives agriculture towards sustainable development. This paper combs the research status of picking robots by combining literature collation and market research, shows the scientific research results of various types of orchard picking robots at home and abroad, makes an in-depth analysis of the existing problems, and discusses the basic system composition of orchard picking robots Existing problems, and propose solutions to the problems found. Orchard picking robot has a huge application space in China, but due to the difficulty of research and development, there are still few economical and practical orchard picking robot products at home and abroad. It is necessary to increase the research and development of intelligent picking robots, integrate multidisciplinary high and new technologies, vigorously carry out innovative research on intelligent picking technology and equipment, improve the precision, portability, and low cost of robots, and promote the early application of orchard picking robots in China.

Spectroscopy-based chemometrics combined machine learning modeling predicts cashew foliar macro- and micronutrients

Precision nutrient management in orchard crops needs precise, accurate, and real-time information on the plant’s nutritional status. This is limited by the fact that it requires extensive leaf sampling and chemical analysis when it is to be done over more extensive areas like field- or landscape scale. Thus, rapid, reliable, and repeatable means of nutrient estimations are needed. In this context, lab-based remote sensing or spectroscopy has been explored in the current study to predict the foliar nutritional status of the cashew crop. Novel spectral indices (normalized difference and simple ratio), chemometric modeling, and partial least square regression (PLSR) combined machine learning modeling of the visible near-infrared hyperspectral data were employed to predict macro- and micronutrients content of the cashew leaves. The full dataset was divided into calibration (70 % of the full dataset) and validation (30 % of the full dataset) datasets. An independent validation dataset was used for the validation of the algorithms tested. The approach of spectral indices yielded very poor and unreliable predictions for all eleven nutrients. Among the chemometric models tested, the performance of the PLSR was the best, but still, the predictions were not acceptable. The PLSR combined machine learning modeling approach yielded acceptable to excellent predictions for all the nutrients except sulphur and copper. The best predictions were observed when PLSR was combined with Cubist for nitrogen, phosphorus, potassium, manganese, and zinc; support vector machine regression for calcium, magnesium, iron, copper, and boron; elastic net for sulphur. The current study showed hyperspectral remote sensing-based models could be employed for non-destructive and rapid estimation of cashew leaf macro- and micro-nutrients. The developed approach is suggested to employ within the operational workflows for site-specific and precision nutrient management of the cashew orchards.

Competition or facilitation for stored soil water by cover crops in succession and additional effect of fertilization in a juvenile tung-based intercropping system

Intercropping or agroforestry systems are among the strategies used to prevent soil erosion or crusting and water loss by evaporation in the bare soil during early growth stage of tree crop plantations. However, the pattern of water use in intercropped, juveline orchard crop plantations is still poorly known. This study aimed to evaluate competition or facilitation for soil water stored by cover crops in rotation and the impact of additional fertilization in a juvenile tung-based intercropping system in southern Brazil during the winter and summer periods of 2012/2013 and 2013/2014 growing seasons. A split plot in randomized complete block design arrangement, with four replications, was used comprising crambe winter cover crop plus poultry manure or nitrogen, potassium and phosphorus (NPK) fertilizer; a mixture of oats and vetch, sunflower, and soybean in rotation; and sole tung as control. Cover crop intercropping significantly increased water content of the surface layer of the juvenile tung soil only at the beginning of the second growing season. The cover crops showed interspecific facilitation for water use by tung during the summer period, but no clear-cut trend for the winter cover crops. The additional organic manure did not enhance profile soil water storage. Any of the summer cover crops (soybean, sunflower, or peanut) could be used for soil and water conservation in juvenile tree crop plantations. Further studies are required during the winter season to establish whether the winter cover crops are competitors or facilitators for stored soil water in agroforestry systems.

Study the Physical Properties of Fertilizers and Plant Basin Parameters to Design the Tractor Operated Round Basin Maker cum Fertilizer Applicator for Orchard Crop

The physical form of fertilizer production is of extremely importance, both agronomically and in regard to satisfactory handling, transport, storage, and finally application to the field. The improvement of equipment for handling, storage, and application of granular fertilizer require a proper understanding of material properties and flow behavior. The most common problems encountered in fertilizers were caking, poor flow ability, segregation, dustiness and excessive hygroscopicity due to differences of physical properties. The physical properties such as moisture content, angle of repose and bulk density as important in designing the hopper and metering roller of fertilizer plays an important role in the storage, transport and application of fertilizer. The urea, Ammonium phosphate Sulphate, complex fertilizers and fertilizer ratio (10 26 26) per one orchard tree should be applied yearly trice based on crop requirement. The angle of repose value ranges 28° -37° the hopper angle was decided. For that, to flow the fertilizer freely from the hopper, the inclined angle of the hopper should be greater than 40° respectively. The lowest bulk density and tapped density observed 0.648 kg cm-3 and 0.708 kg cm-3 respectively. Coefficient friction for galvanized Iron (GI) material is very high So, based on the obtained results, a fertilizer applicator for orchard crops has been designed. The basin diameter of orchard palm varies from 1500 mm to 1750 mm the mean of 1650 mm. The root zone depth of orchard crop varies from 150 to 180 mm at radius of 1800 mm from the base of palm. The mean 171.66 mm hence depth of operation of machine was selected as 150 mm such that the machine does not interfere with root zone of orchard trees.

МНОГОФАКТОРНЫЕ МОДЕЛИ УПРАВЛЕНИЯ УСТОЙЧИВОСТЬЮ ВОСПРОИЗВОДСТВЕННЫХ ПРОЦЕССОВ В МНОГОЛЕТНИХ АГРОЦЕНОЗАХ НА ОСНОВЕ КОГНИТИВНЫХ МЕТОДОВ АНАЛИЗА

The necessity of developing multifactorial models for managing the sustainability of reproductive processes in perennial agrocenoses with the participation of orchard crops and grapes is substantiated. The factors influencing the sustainability and efficiency of the production of fruit products and grapes in the Krasnodar region have been identified. Cognitive models for managing the sustainability of reproductive processes in perennial agrocenoses based on technological processes of elements of the fruit and grape-growing management system have been developed. Models for managing the sustainability of reproductive processes are based on cognitive methods of analysis and digital technologies, taking into account the identified systemic relationships in reproductive processes in functional areas of impact according to criteria of efficiency; biologization; environmental management. Cognitive models have made it possible to identify multifunctional relationships in reproductive processes in functional areas of influence, the optimization of which is the basis for the development of digital technologies. The results of cognitive modeling will be the basis for solving applied problems to increase the productivity of fruit agrocenoses, reduce the level of chemical and anthropogenic load on their elements and optimize the costs of production of industrial products. normative parametric model of the stability of reproductive processes in perennial agrocenoses with the participation of orchard crops and grapes has been developed. The tools for managing biotechnological processes in the elements of agrocenosis are proposed. Key words: MODELS, MANAGEMENT, SUSTAINABILITY, COGNITIVE MODELING, COGNITIVE MAPS, DIGITAL TECHNOLOGIES, EFFICIENCY

Dynamics of the soil microbial community associated with Morchella cultivation: diversity, assembly mechanism and yield prediction.

The artificial cultivation of morels has been a global research focus owing to production variability. Understanding the microbial ecology in cultivated soil is essential to increase morel yield and alleviate pathogen harm. A total of nine Morchella cultivation experiments in four soil field types, forest, paddy, greenhouse, and orchard in Shanghai city were performed to determine the potential ecological relationship between Morchella growth and soil microbial ecology. Generally, significant variation was observed in the soil microbial diversity and composition between the different experimental field types. The niche width analysis indicated that the bacterial habitat niche breadth was significantly greater than the fungal community width, which was further confirmed by a null model that revealed that homogeneous selection could explain 46.26 and 53.64% of the variance in the bacterial and fungal assemblies, respectively. Moreover, the neutral community model revealed that stochastic processes dominate the bacterial community in forests and paddies and both the bacterial and fungal communities in orchard crops, whereas deterministic processes mostly govern the fungal community in forests and paddies and both the bacterial and the fungal communities in greenhouses. Furthermore, co-occurrence patterns were constructed, and the results demonstrated that the dynamics of the soil microbial community are related to fluctuations in soil physicochemical characteristics, especially soil potassium. Importantly, structural equation modeling further demonstrated that the experimental soil type significantly affects the potassium content of the soil, which can directly or indirectly promote Morchella yield by inhibiting soil fungal richness. This was the first study to predict morel yield through soil potassium fertilizer and soil fungal community richness, which provides new insights into deciphering the importance of microbial ecology in morel agroecosystems.

Supplemental nesting habitat increases bee abundance in apple orchards

Abstract Identifying the resources that limit bee populations is essential for both bee conservation and pollination management in agroecosystems. Land‐use change typically leads to decreased habitat availability for wild pollinators, including loss of nesting habitat, which is an essential but often‐overlooked resource for wild bees. Cavity‐nesting bees, such as many Osmia spp. (Hymenoptera: Megachilidae), occupy holes in wood or reeds to build their nests; due to their nesting habits, they are frequently scarce in agricultural settings. Nevertheless, under the right circumstances, these bees can be ideal pollinators of apple and other orchard crops. Artificial nesting structures (‘bee hotels’ or ‘trap‐nests’) are often used to study cavity‐nesting bees and have been proposed as tools for bee conservation. To evaluate the effects of additional nesting habitat on the local abundance of pollinators, we selected 24 sites in apple orchards in eastern Canada in 2021 and 2022. Each site comprised two study plots: one in which we installed artificial nesting structures for cavity‐nesting bees, and one without added nesting habitat (control). Pollinator surveys were conducted in both plot types to measure pollinator visits to apple blossoms and, after apple bloom, to flowers in the undergrowth and/or in shrubs. Numbers and size of developing fruit were also recorded. Both Osmia bees and overall pollinator numbers were significantly higher in the treatment with trap‐nests (respectively, 33% and 22% higher during the 2021 growing season, and 113% and 30% higher during apple bloom across the 2 years of the study); however, there was no consistent difference in apple size or fruit set between the two treatments. Thus, trap‐nests locally increased the numbers of cavity‐nesting bees as well as total pollinator numbers, but they had little effect on apple yield, likely because apple production was not pollinator limited in the years of this study. Synthesis and applications. These findings suggest that bee populations in apple orchards can be limited by nesting resources such that addition of constructed nesting habitat could be an effective means of increasing pollinator numbers in orchards, and potentially, supporting bee conservation.

Evaluation of weed control efficacy and crop safety of the PPO-inhibiting herbicide tiafenacil in California orchard cropping systems

Abstract Tiafenacil is registered in the United States for use in annual crops such as corn and soybean, but not on orchard crops. Field studies were conducted to determine orchard crop safety and efficacy of tiafenacil on important California orchard weeds. To evaluate crop safety, tiafenacil was applied at 74, 148, and 222 g ai ha−1 alone and with 38 g ai ha−1 of tolpyralate three times per year at the base of almond, pistachio, prune, and walnut trees. The first treatment was applied 2 mo after the trees had been transplanted. In all four tree crop experiments, treatments were applied once in May 2020, then three times again during the winter of 2021 and 2022 at 21-d treatment intervals. There were no visual foliar injury symptoms or treatment-related effects on tree trunk diameter change even at the highest tested rate of tiafenacil applied seven times over three growing seasons. In a separate study of weed control, in most instances, tiafenacil applied at 12 g ai ha−1 performed similarly to that of tiafenacil plus glufosinate. Control of glyphosate-resistant hairy fleabane with tiafenacil applied alone at 25 g ai ha−1 was 65% by 14 d after treatment. Tiafenacil applied at 50 g ai ha−1 to hairy fleabane performed similarly to glufosinate plus glyphosate. In a greenhouse study, tiafenacil applied at 12 g ha−1 provided 95% to 100% control of barnyardgrass and junglerice, and there was no significant difference between tiafenacil applied alone or with glufosinate. Saflufenacil applied alone or in a mixture with glufosinate was not as effective as the tiafenacil treatments for grass weed control. Based on experiments conducted over three growing seasons in four tree fruit and tree nut crops, tiafenacil crop safety appeared to be acceptable even at up to 2- or 3-fold the expected use rate.

Open-Format Prescription Maps for Variable Rate Spraying in Orchard Farming

Highlights Straightforward procedure to code prescription maps independent of manufacturers. Methodology suitable for orchard crops and vineyards including pressures up to 10 bar and flowrates up to 100 L/min. Algorithm validated for both trellis-based continuous rows and traditional orchard rows of discrete trees. Method scalable to other agricultural operations, such as fertilizing or data registration for auditing purposes. Abstract. The implementation of crop protection solutions contributing to significant reductions in the use and risk of chemical pesticides has motivated the interest of site-specific systems, such as variable rate technologies based on user-set prescriptions. However, the practical implementation of variable rates has been dissuasive for many growers who are not familiar with digital solutions, as proprietary firmware is often difficult to grasp. This paper presents a method for formatting prescription maps that is independent of manufacturers, can be easily and freely implemented by industry and can be adopted by growers not familiar with advanced software tools. The methodology was successfully demonstrated for perennial specialty crops, in particular for trellised vineyards in vertical shoot position and for traditional olive groves. Results showed that the variations within user prescription maps were translated to the fields, but flow errors appeared due to the challenge of measuring flow and pressure in the highly pulsating actuation of pulse-width-modulated (PWM) valves. Such errors diminished with the use of low-volume rates and the optimal selection of the nozzles when adjusted to the real pressure measured in the field. The use cases validated in the field showed the consistency of the method for highly populated prescription maps of 1,221 points/ha accessible to advanced farmers, as well as for modest maps of 80 points/ha within reach of the majority of growers. Keywords: Automated map building, Local tangent plane coordinates, Orchard crop operations, Precision farming, Prescription maps, User-centered approach, Variable rate spraying.

Significant opportunities for tree crop expansion on marginal lands in the Midwest, USA

AbstractIntroductionTree crop orchards can help diversify the monocropping practices in agricultural lands such as the Midwestern region of the United States which is currently dominated by corn‐soybean rotation. These crops can not only expand farm income but also help stabilize soil, purify water, and provide other ecosystem services. Despite these benefits, tree crops as agroforestry systems are not widely established in the region. Identifying marginal land that is more suitable for tree crops over row crops can help the growers and the environment.Materials and MethodsUsing the case of Missouri, USA, this study mapped marginal land for nut‐producing tree crops using a three‐step process. The first step includes the identification of marginal land suitable for a wide variety of tree crops. The second step involved GIS‐based multicriteria analysis of biophysically suitable areas for three commercially viable tree species, that is, eastern black walnut, pecan, and Chinese chestnut. The final step maps the marginal land for tree crops based on their suitability to grow under different environmental vulnerabilities, mainly flooding, erosion, and sloped conditions. The Gridded Soil Survey Geographic Database developed by the United States Department of Agriculture provided information on soil biophysical and environmental characteristics.ResultsThe spatial analysis showed that Missouri has around 16,000 sq. km of land suitable for Black walnut, followed by 10,801 sq. km and 4587 sq. km for pecan and Chinese chestnut, respectively. The study found very few tree crop orchards on these marginal lands.ConclusionThere are ample opportunities to expand tree crops on marginal cropland. Converting these lands to tree crops could provide communities with economic, human health, and environmental benefits. This multistep methodology could serve as a screening tool to identify tree‐cropping areas for environmental improvement and rural America's economic revitalization.

Perennial Peanut as a Potential Living Mulch and Nitrogen Source for Citrus and Other Orchard Crops in Florida

The concept of using a perennial peanut as a living mulch and source of biological nitrogen in fruit and nut crop orchards is not a new idea. In Central and South America, perennial peanuts have long been incorporated as a living groundcover into palm, coffee, cacao, plantain, and citrus, as well as into other fruit and nut production orchards. This cover crop may pose as a viable, environmentally-friendly option for production in Florida, too.

Effect of Growth Regulators on the Quality of Apple Tree Whorls

High-quality nursery stock ensures the dynamic development of orchard crops. The most desirable by orchardists is a tree with a strongly developed crown, which makes it possible to shorten the investment period of newly planted orchards. The quality of the perianth and the degree of its branching depend on the growth strength of the rootstock, the ability of a given variety to form lateral shoots, the type and effectiveness of the treatments used to stimulate branching, soil and climatic conditions related to the location of the nursery and the course of the weather during the period of initiation and growth of young shoots. The study was conducted in 2017–2019 at a private nursery farm near Lublin. The aim of the experiment was to study the effect of mixtures based on the compounds benzyladenine (BA) and gibberellins (GA3) and (GA4+7) for chemical stimulation of lateral shoot outgrowth in apple cv. ‘Alwa’ and ‘Najdared’. In the course of the research, significant effects of the type of growth regulations used and the variety on the height of the perianths, the number and length of lateral shoots and the degree of branching were demonstrated.