Machine Vision Systems – A Tool for Automatic Color Analysis in Agriculture

It was in the early 1960s when machine vision systems initiated researchers and developers have worked on building machines that perform tasks of acquisition, processing, and analysis of images in a wide range of applications for different areas. Currently, along with the new technological advances in electronics, computer systems, image processing, pattern recognition, and mechatronics, it has arose the opportunity to improve machine vision systems development with affordable implementations at lower cost. A machine vision system is the combination of several high-tech techniques, including both hardware and software, used to acquire, process, and analyze images on a machine, which contributes with a set of tools for the extraction of features, such as color and dimension parameters, texture, chemical components, disease detection, freshness, assessment, modeling, and control, among others. Based on former paragraphs, we could say that machine vision systems are appropriate to improve the actual agricultural systems making them more useful, efficient, practical, and reliable

Sensing and Automation Technologies for Ornamental Nursery Crop Production: Current Status and Future Prospects

The ornamental crop industry is an important contributor to the economy in the United States. The industry has been facing challenges due to continuously increasing labor and agricultural input costs. Sensing and automation technologies have been introduced to reduce labor requirements and to ensure efficient management operations. This article reviews current sensing and automation technologies used for ornamental nursery crop production and highlights prospective technologies that can be applied for future applications. Applications of sensors, computer vision, artificial intelligence (AI), machine learning (ML), Internet-of-Things (IoT), and robotic technologies are reviewed. Some advanced technologies, including 3D cameras, enhanced deep learning models, edge computing, radio-frequency identification (RFID), and integrated robotics used for other cropping systems, are also discussed as potential prospects. This review concludes that advanced sensing, AI and robotic technologies are critically needed for the nursery crop industry. Adapting these current and future innovative technologies will benefit growers working towards sustainable ornamental nursery crop production

A Low-cost Depth Imaging Mobile Platform for Canola Phenotyping

To meet the high demand for supporting and accelerating progress in the breeding of novel traits, plant scientists and breeders have to measure a large number of plants and their characteristics accurately. A variety of imaging methodologies are being deployed to acquire data for quantitative studies of complex traits. When applied to a large number of plants such as canola plants, however, a complete three-dimensional (3D) model is time-consuming and expensive for high-throughput phenotyping with an enormous amount of data. In some contexts, a full rebuild of entire plants may not be necessary. In recent years, many 3D plan phenotyping techniques with high cost and large-scale facilities have been introduced to extract plant phenotypic traits, but these applications may be affected by limited research budgets and cross environments. This thesis proposed a low-cost depth and high-throughput phenotyping mobile platform to measure canola plant traits in cross environments. Methods included detecting and counting canola branches and seedpods, monitoring canola growth stages, and fusing color images to improve images resolution and achieve higher accuracy. Canola plant traits were examined in both controlled environment and field scenarios. These methodologies were enhanced by different imaging techniques. Results revealed that this phenotyping mobile platform can be used to investigate canola plant traits in cross environments with high accuracy. The results also show that algorithms for counting canola branches and seedpods enable crop researchers to analyze the relationship between canola genotypes and phenotypes and estimate crop yields. In addition to counting algorithms, fusing techniques can be helpful for plant breeders with more comfortable access plant characteristics by improving the definition and resolution of color images. These findings add value to the automation, low-cost depth and high-throughput phenotyping for canola plants. These findings also contribute a novel multi-focus image fusion that exhibits a competitive performance with outperforms some other state-of-the-art methods based on the visual saliency maps and gradient domain fast guided filter. This proposed platform and counting algorithms can be applied to not only canola plants but also other closely related species. The proposed fusing technique can be extended to other fields, such as remote sensing and medical image fusion

Thermography to assess grapevine status and traits opportunities and limitations in crop monitoring and phenotyping – a review

Mestrado em Engenharia de Viticultura e Enologia (Double degree) / Instituto Superior de Agronomia. Universidade de Lisboa / Faculdade de Ciências. Universidade do PortoClimate change and the increasing water shortage pose increasing challenges to agriculture and viticulture, especially in typically dry and hot areas such as the Mediterranean and demand for solutions to use water resources more effectively. For this reason, new tools are needed to precisely monitor water stress in crops such as grapevine in order to save irrigation water, while guaranteeing yield. Imaging technologies and remote sensing tools are becoming more common in agriculture and plant/crop science research namely to perform phenotyping/selection or for crop stress monitoring purposes. Thermography emerged as important tool for the industry and agriculture. It allows detection of the emitted infrared thermal radiation and conversion of infrared radiation into temperature distribution maps. Considering that leaf temperature is a feasible indicator of stress and/or stomatal behavior, thermography showed to be capable to support characterization of novel genotypes and/or monitor crop’s stress. However, there are still limitations in the use of the technique that need to be minimized such as the accuracy of thermal data due to variable weather conditions, limitations due to the high costs of the equipment/platforms and limitations related to image analysis and processing to extract meaningful thermal data. This work revises the role of remote sensing and imaging in modern viticulture as well as the advantages and disadvantages of thermography and future developments, focusing on viticultureN/

Reconstruction of tree branching structures from UAV-LiDAR data

The reconstruction of tree branching structures is a longstanding problem in Computer Graphics which has been studied over several data sources, from photogrammetry point clouds to Terrestrial and Aerial Laser Imaging Detection and Ranging technology. However, most data sources present acquisition errors that make the reconstruction more challenging. Among them, the main challenge is the partial or complete occlusion of branch segments, thus leading to disconnected components whether the reconstruction is resolved using graph-based approaches. In this work, we propose a hybrid method based on radius-based search and Minimum Spanning Tree for the tree branching reconstruction by handling occlusion and disconnected branches. Furthermore, we simplify previous work evaluating the similarity between ground-truth and reconstructed skeletons. Using this approach, our method is proved to be more effective than the baseline methods, regarding reconstruction results and response time. Our method yields better results on the complete explored radii interval, though the improvement is especially significant on the Ground Sampling Distance In terms of latency, an outstanding performance is achieved in comparison with the baseline method.Junta de Andalucia 1381202-GEU PYC20-RE-005-UJAEuropean Commission Spanish Government PID2021-126339OB-I00 FPU17/01902 FPU19/0010

Vegetable Crops

In ancient times, people benefited from ingesting different parts of various weeds (root, stem, shoot, leaf, flower, fruit, seed, etc.) to maintain a healthy life. People have obtained the vegetables we grow today by succeeding in cultivating these weeds. This book explains the health benefits of vegetable crops, organic vegetable growing, greenhouse management, and principles of irrigation management for vegetable crops

STUDIES OF QUALITY AND NUTRIENT USE EFFICIENCY IN VEGETABLE CROPS GROWN UNDER DIFFERENT SUSTAINABLE CROPPING SYSTEM

Lo scopo del progetto di dottorato \ue8 stato quello di valutare gli effetti a livello fisiologico, biochimico e molecolare di prodotti biostimolanti su ortaggi da foglia (lattuga e rucola) e di approfondire la conoscenza sulla loro modalit\ue0 di azione. La prima parte del lavoro ha riguardato lo studio degli effetti di estratti acquosi di foglie (LE) e fiori (FE) di Borago officinalis L. su piante di lattuga, attraverso l\u2019utilizzo di tecniche di fenomica, agronomia, fisiologia e biochimica. I risultati ottenuti hanno mostrato come gli estratti di borragine siano in grado di aumentare il metabolismo primario e secondario nelle piante trattate. La concentrazione di flavonoidi totali, fenoli e proteine totali, come anche l\u2019attivit\ue0 in vitro della PAL e dei relativi livelli di proteine hanno mostrato un aumento a seguito dei trattamenti, in particolare dopo l\u2019applicazione dell\u2019estratto a base di fiori di borraggine. L\u2019estratto di fiori si \ue8 dimostrato efficace anche nel prevenire la degradazione dei pigmenti fotosintetici durante la conservazione post raccolta di foglie di lattuga. Si pu\uf2 quindi affermare che gli estratti a base di borragine, in particolare l\u2019estratto a base di fiori, sembrano possedere attivit\ue0 biostimolante su piante di lattuga. Gli stessi estratti sono stati applicati anche su piante di rucola, per verificare l\u2019influenza dei trattamenti sul metabolismo del nitrato e osservare le risposte indotte a livello molecolare. \uc8 stata effettuata l\u2019analisi dell\u2019espressione genica dei principali geni che codificano per gli enzimi coinvolti nel metabolismo del nitrato (nitrato reduttasi DtNR, nitrito reduttasi DtNiR, glutammato sintasi DtGLU, glutammina sintetasi DtGS1, trasportatore del nitrato DtNTR). Il risultato pi\uf9 interessante \ue8 stato, a livello biochimico, la marcata riduzione della concentrazione di nitrato nelle foglie di rucola a seguito dei trattamenti, influenza confermata anche dall\u2019incremento dell\u2019attivit\ue0 della nitrato reduttasi in vivo. I trattamenti hanno influenzato anche l\u2019espressione dei geni studiati, confermando che gli estratti testati hanno un ruolo nei processi fisiologici in cui tali geni sono coinvolti. Sono state anche svolte analisi mirate ad una migliore caratterizzazione gli estratti. \uc8 stata valutata l\u2019attivit\ue0 ormono-simile degli estratti su mutanti di mais e, considerando le numerose propriet\ue0 attribuite alla borragine, \ue8 stata anche testata la possibile attivit\ue0 allelopatica degli estratti sulla germinazione di differenti specie erbacee. L\u2019estratto a base di foglie ha mostrato un moderato effetto auxino-simile. Entrambi gli estratti di borragine sembrano possedere un effetto di inibizione sulla germinazione delle specie testate. \uc8 stata inoltre condotta un\u2019attivit\ue0 in collaborazione con un\u2019azienda multinazionale per valutare l\u2019efficacia di alcuni biostimolanti commerciali e prototipi sulla qualit\ue0 di ortaggi da foglia e sulla protezione contro stress di tipo abiotico (in particolare stress salino).The purpose of the Ph. D. research project was to investigate the effects of biostimulant products on leafy vegetables (lettuce and rocket) and deepen the knowledge on their mode of action. The first part of the work regarded the further deepening of the effects of aqueous extracts obtained from leaves (LE) and flowers (FE) of Borago officinalis L. on lettuce, involving phenomic, agronomic, physiological, and biochemical aspects. Results showed that borage extracts enhanced the primary metabolism. Total flavonoids and phenols, as well as the total protein levels, the in vitro PAL specific activity, and the levels of PAL-like polypeptides increased by all borage extracts, with particular regards to FEs. FEs also proved efficient in preventing degradation and inducing an increase in photosynthetic pigments during storage. In conclusion, borage extracts, with particular regard to the flower ones, appear indeed to exert biostimulant effects on lettuce. The borage extracts were also applied on rocket plants, to investigate the influence of treatments on nitrate assimilation pathway and on the molecular responses. Gene expression analysis of the main enzymes involved in the nitrate metabolism (DtNR, DtNiR, DtGLU, DtGS1, DtNTR) was evaluated. From the biochemical point of view, the most interesting result was surely the substantial reduction of nitrate level caused by both extracts, confirmed also by the increment of the NR in vivo activity. Borage treatments influenced also the gene expression, confirming that extracts have a role in the physiological processes in which the considered genes are involved. In addition, work regarding borage extracts characterization was carried out. The auxin- and gibberellin-like activity of extracts on maize mutants was explored and, due to the multitude properties attributed to borage, the allelopathic effects of borage extracts on seeds germination of different plant species was investigated. LE treatment seems to possess a slight auxin-like activity. The bioassay on allelopathic properties of borage LE and FE demonstrated that they exert an effect on seeds germination (inhibition effect). The work included also an activity carried out in collaboration with a private company to study the effectiveness of commercial biostimulants and prototypes on leafy vegetables quality and protection against abiotic stresses (salt stress)