Design, development and testing of feeding grippers for vegetable plug transplanters

Vegetable transplanting is an important and advantageous practice in vegetables production systems. In recent years, the development of vegetable transplanting tools has increased, as well as the interest for automatic and robotic transplanters. However, at present, the feeding of transplanting machines is often still performed by hand. This paper presents the design, development and testing of a needle gripper and a two-finger gripper for vegetable transplanting. Both grippers were self-designed and tested for picking, lifting and transplanting plug seedlings. Tests have been conducted on fennel (Foeniculum vulgare L.), leek (Allium ampeloprasum L.) chicory (Cichorium intybus L.) and lettuce (Lactuca sativa L.) seedlings to determine the impact that gripper typology might have on the further growth of plants after transplanting. The average success rate of the two-finger gripper in the transplanting experiment was 95% and of the needle gripper 81.75%, respectively. Although neither gripper typology affected the growth of the seedlings after transplanting, several design implications were identified in order to improve the performance of both grippers. Furthermore, the two-finger gripper is more reliable for lettuce and chicory, while the needle gripper requires root plugs with higher firmness and cohesion to prevent shattering

A New Method for Hybrid Bermuda Grass (Cynodon dactylon × C. transvaalensis Burtt.-Davy) Vegetative Propagation

Hybrid Bermuda grasses (Cynodon dactylon × C. transvaalensis Burtt.-Davy) represent one of the greatest contributions to the growing quality of turfgrass in the warm season and transition zone areas of the world. Hybrid Bermuda grass production relies on vegetative propagation from sod or sprigs. In the past, efforts have focused on improving the technique of stolonizing (or sprigging) for establishment in new areas. Such propagation requires bulk harvesting and planting of all rhizomes and stolons. We have developed a novel method of propagation and establishment from a single node harvested from greenhouse grown stolons. Despite a stolon fraction bearing a single node being suitable for effectively propagating a warm-season turfgrass, the technique has been held as economically impractical until now. Our method has been developed to obtain the multiplication of plant material in soilless conditions by harvesting single-node sprigs, propagation of plants from the single nodes, and transplant of single plants in the field. The investigation aimed to identify values for method set-up. Indeed, node and internode size variability with differential between maximum diameters is crucial for discrimination. For Patriot Bermuda grass stolons, nodes exhibited a maximum diameter of 2.43 ± 0.46 mm, while internodes had a maximum diameter of 1.54 ± 0.16 mm. Based on these findings, a 2 mm sieve was selected, achieving an optimal ratio between the node fraction and internode residues. The sieve yielded 87% of node fractions and only 1% of internodes from the initial mix, demonstrating its efficacy. Further results for the transplanting phase indicated that a double release resulted in an average success rate of 98.8%, with only 6.9% blank cells when using a single release. The average was 149 plants per tray over 160 cells, representing a 93.1% success rate. These results underscore the efficiency and acceptability of the overall propagation process in alignment with market references

Innovative Living Mulch Management Strategies for Organic Conservation Field Vegetables: Evaluation of Continuous Mowing, Flaming, and Tillage Performances

Organic vegetable production is particularly affected by weed pressure and mechanical weeding is the major tactic implemented by growers to keep weeds under economic thresholds. Living mulch (LM) has been shown to provide several environmental services; however, LM management is required to avoid competition between service crops and cash crops. The aim of this trial was to evaluate two innovative LM-based management systems: a system that provided LM growth regulation by means of flaming (LM-FL) and a system where the LM was regularly mowed by an autonomous mower (LM-AM), both compared with a control without LM and based on standard tillage operations (TILL). The three management systems were evaluated in terms of crop production, weed control, and energy consumption on a 2 yr organic crop rotation of cauliflower (Brassica oleracea L. var botrytis) and eggplant (Solanum melongena L.). LM-AM produced an acceptable fresh marketable yield for both vegetable crops. Moreover, the weed dry biomass obtained in LM-AM-managed plots was lower compared to the LM-FL plots and ranged approximately from 200 to 300 kg ha−1. Furthermore, LM-AM management resulted in lower energy consumption (−2330 kWh ha−1 with respect to the TILL system and −7225 kWh ha−1 with respect to the LM-FL system). The results of this trial suggest that autonomous mowers have a great potential to improve LM management and help with implementing sustainable organic vegetable systems

Effetti di trinexapac etile e surfactanti del suolo sui consumi idrici di Cynodon dactylon "Princess 77"

I tappeti erbosi sono un'importante componente del paesaggio e garantiscono anche diverse tipologie di benefici come quelli estetici, economici e funzionali. Tuttavia, questi vantaggi non sono sufficienti a giustificare l'elevato consumo di acqua potabile necessario ad assicurare un'accettabile qualità di tale coltura. In aggiunta, lo scenario mondiale in termini di disponibilità di acqua non è incoraggiante. A tal proposito, da tempo si sono studiate e applicate differenti strategie e diversi approcci nella gestione dei tappeti erbosi al fine di ridurre i consumi idrici delle colture pur mantenendo qualità accettabile. Tra questi ritroviamo: l'uso di fonti alternative di acqua, l'adozione di sistemi irrigui più efficienti, la tecnica del deficit d'irrigazione, l'uso di varietà resistenti alla siccità, l'applicazione di alcuni prodotti che permettono di ridurre l'ET della coltura ed infine la combinazione di due o più di queste tecniche. L’obiettivo di questo studio è quello di investigare gli effetti che il Trinexapac-etile (TE), un regolatore di crescita, e un surfactante del suolo determinano sulla qualità generale di un tappeto erboso di Cynodon dactylon cv "Princess 77" sottoposto a differenti livelli di stress idrico. Considerando che la bibliografia riporta numerosi casi di successo riguardo l’effetto che i due prodotti chimici esercitano sulla qualità del tappeto erboso, si ipotizza che tali composti applicati in combinazione possano garantire maggiori prestazioni del tappeto erboso a minori livelli di ET rispetto a quando distribuiti singolarmente. Scopo finale del progetto è quello di comparare gli effetti del surfactante del suolo, del TE e la loro combinazione su diversi parametri di un tappeto erboso come colore, qualità e umidità del suolo a 3 differenti livelli di ET (50%, 65% e 80%). Tale progetto è stato svolto presso il golf course della New Mexico State University dal mese di maggio 2016 al mese di Novembre 2016

Innovative Machines for Weed control in Conservation Agriculture

Ad oggi, sono state sviluppate molte tecnologie per ottenere un effetto di controllo delle infestanti accettabile insieme a un basso consumo energetico. La grande sfida, infatti, è introdurre nell'ambiente naturale la quantità minima di energia necessaria per il controllo delle erbe infestanti e trasformarla in agricoltura di produzione. Questo progetto di dottorato mira a studiare l'effetto di controllo delle infestanti delle falciatrici autonome in due diversi contesti: agricoltura conservativa e tappeti erbosi. Nello specifico, per il concorso dell'agricoltura conservativa, sono state testati tagliaerba autonomi in vigneto e un sistema orticolo a gestione biologica nel centro Italia. Entrambi i campi sperimentali consistevano in una consociazione tra la coltura da reddito e una cover crop. Le prestazioni dei tagliaerba autonomi in termini di effetto diserbante, efficienza del lavoro e consumo energetico sono state valutate e confrontate con altre pratiche gestionali. Nel tappeto erboso, invece, i taglierba autonomi sono stati studiati e confrontati diversi modalità taglio per determinare la soluzione operativa più sostenibile in termini di efficienza del lavoro, consumo energetico e qualità del tappeto erboso. Infine, è stato sviluppato e testato un algoritmo di rilevamento degli oggetti per la sua capacità di rilevare le specie infestanti in uno scenario con uno sfondo complesso come i tappeti erbosi. To date, many technologies have been developed to achieve an acceptable weed control effect together with a low energy consumption. Indeed, the big challenge is to introduce the minimum amount of energy needed for weed control in the natural environment and turn it into production agriculture. This PhD project aim to investigate the weed control effect of autonomous mowers in two different contexts: conservation agriculture and turfgrasses. Specifically, for the conservation agriculture contest, autonomous mowers were tested in a vineyard and an organically managed vegetable cropping system in central Italy. Both experimental fields consisted of an intercropping between the cash crop and an agro-ecological service crop as a living mulch. Autonomous mowers performances in terms of weed control, work efficacy and energy consumption were assessed and compared with other management practices. In turfgrass, instead, autonomous mowers different mowing patterns were studied and compared to determine the most sustainable operative solution in terms of work efficacy, energy consumption and turf quality. Finally, and object detection algorithm was developed and tested for its capacity to detect weeds in scenario with complex background such as turfgrasses

Case Report of <i>Avena sterilis</i> subsp. <i>sterilis</i> ACCase Herbicide Resistance in Southern Spain

Wild oats are worldwide grassy weeds that cause substantial yield losses, particularly in winter cereal crops. In addition, wild oat herbicide resistant cases have increased; indeed, up to 52 cases have been registered. Despite this, no wild oat herbicide resistant cases have been described in Spain, where farmers and technicians have reported poor herbicide efficacy in sterile oats (Avena sterilis subsp. sterilis L.). A dose-response experiment was conducted comparing the behavior of two populations of A. sterilis from southern Spain to a susceptible population. These populations were collected from two commercial farms where a low efficacy of chemical control had been described. Clodinafop-propargyl and Pinoxaden were tested as active ingredients in the dose-response experiment. Additionally, an alternative herbicide, which consisted of a mixture of Mesosulfuron-methyl and Propoxycarbazone-Na, was also tested at a field dose. The two populations of A. sterilis studied provided a resistant factor higher than 10 for Clodinafop-propargyl and higher than 4 for Pinoxaden. A total control was achieved for plants treated with Mesosulfuron-methyl and Propoxycarbazone-Na

Small autonomous machines for sustainable soil management in vegetable crops and orchards

In specialty crops, the interest in developing autonomous machines for weed management has grown significantly because of the decreased availability of effective herbicides, labor shortages, and high labor costs. Small autonomous mowers with random path planning, despite relaying on simplified computational resources, obtained prom- ising results when applied in agricultural contexts, including vegetable systems, orchards and vineyards, even when compared with conven- tional systems. The intensive mowing activity of these mowers allows to control weeds growth and seed production, limiting their spread. These machines achieved also encouraging results for the management of liv- ing mulch, whose growth needs to be controlled to prevent competition with the cash crop. In addition, the use of these small autonomous mow- ers with random path planning showed to reduce the primary energy consumption and CO2 emissions of the management system, contribut- ing to improve the sustainability of floor management. Nevertheless, further improvement of these machines is needed for the mechanization of a professional farm

Continuous Mowing for <i>Erigeron canadensis</i> L. Control in Vineyards

Erigeron canadensis L. directly competes with vines for nutrients, light, and water, and its management represents a challenge, especially under a vineyard trellis. Conventional weed control in the under-trellis area is achieved by cultivation or multiple herbicides applications, thus leading to relevant environmental issues. For this reason, several eco-friendly or nature-based weed control strategies such as the use of cover crops (CC) that become more relevant in last years. A two-year trial was conducted on a vineyard aimed at evaluating the effect of CC (sown both inter-rows and under-trellis) managed with an autonomous mower (AM) on E. canadensis under trellis control. The combination of CC and AM provided an E. canadensis reduction between 61 and 84% compared to conventional management. The AM work when managing a spontaneous cover provided a density reduction of 26%. Moreover, an analysis of the trampling effect of the AM on the vineyard floor and E. canadensis density was conducted

Evolution of Smart Strategies and Machines Used for Conservative Management of Herbaceous and Horticultural Crops in the Mediterranean Basin: A Review

Preserving soil quality and increasing soil water availability is an important challenge to ensure food production for a growing global population. As demonstrated by several studies, conservative crop management, combined with soil cover and crop diversification, can significantly reduce soil and water losses. The aim of this review is to evaluate the spread of smart solutions to perform conservation agriculture (CA) well in the Mediterranean Basin, taking into account the evolution of the strategies and the machines used to perform conservative tillage systems in different contexts in the last 30 years, as well as the effects induced by their adoption on the productivity of herbaceous and horticultural crops, weed control and economic feasibility, in comparison with those obtained utilizing conventional techniques based on soil inversion

Testing of Roller-Crimper-and-Undercutting-Blade-Equipped Prototype for Plants Termination

The use of roller crimpers to terminate plants and obtain a natural mulch before cash crop establishment has been identified as a valid and sustainable approach to control weeds. Several enhancements have been evaluated to improve and speed up plant termination to avoid delays in cash crop planting and consequent yield losses, which can occur with standard roller crimpers. In the present study, a new prototype machine provided with a roller crimper and an undercutting blade, allowing it to simultaneously crimp plant stems and cut root systems, has been designed, realized, and tested. The aim of the research was therefore to evaluate the effectiveness of the prototype for plant termination and to compare it with a commercial roller crimper. The termination was performed on a spontaneous vegetation cover (weeds). A monophasic exponential decay model to evaluate the weed termination rate over time was performed. The fitted model showed that the prototype is able to achieve a greater and faster weed devitalization compared to the commercial roller crimper, with a lower plateau (0.23 vs. 5.35 % of greenness of plant material, respectively) and higher constant of decay (1.45 vs. 0.39 day&minus;1, respectively). Further studies are needed to evaluate the prototype&rsquo;s effectiveness in relation to different soil textures, moisture conditions, and amounts of plant biomass to manage, to further improve the machine and extend its use in a broad range of situations, including cover crop termination