Robotic Heat Treatments for Mango and Prickly Pear Increase Shelf Life and Reduce Pathogen Infection

Mexico is the main exporter of mango fruits and prickly pears, so new postharvest techniques to increase shelf life are studied. Thermal treatments on both fruits can affect their cuticle so it was reviewed. When mango latex remains within the fruits, it avoids sap burn and decreases anthracnose and stem end rot infestation, so two systems were developed to minimize latex de-sapping. A gripper cuts stems 0.5 cm long and cauterizes them with a hot knife implement. A heating gun applied paraffin wax to mangoes without the stem end and protected them better against anthracnose lesions. Physicochemical analysis of several mango varieties was carried out after harvesting, at market place and after pedicel cutting and cauterizing. Keitt mangoes showed the lower quantity of total soluble solids (TSSs) and total acidity (TA). When the pedicel was cauterized, TSS dropped. Two grippers were developed to cryo-cauterize prickly pears as this system is more energy-efficient than hot cauterization. A six-finger gripper moved over a pneumatic actuator toward a dry ice chamber to optimize pear cryo-cauterization. Gripper’s strong grasping damaged the fruits due to excessive compression. TSS and TA of cryo-cauterized fruit remained constant during the three months of fruit storage

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/

Postharvest Technology

Postharvest management of food crops is an important part of food safety and security across the supply chain. It includes processing of agricultural produce, storage, packaging and coating, postharvest disease management, extending shelf life, and maintaining food quality and safety. Postharvest Technology - Recent Advances, New Perspectives and Applications discusses some important aspects of postharvest technologies. Chapters address such topics as postharvest preservation technology, postharvest disease management, and postharvest processing and packaging

Automatic plant features recognition using stereo vision for crop monitoring

Machine vision and robotic technologies have potential to accurately monitor plant parameters which reflect plant stress and water requirements, for use in farm management decisions. However, autonomous identification of individual plant leaves on a growing plant under natural conditions is a challenging task for vision-guided agricultural robots, due to the complexity of data relating to various stage of growth and ambient environmental conditions. There are numerous machine vision studies that are concerned with describing the shape of leaves that are individually-presented to a camera. The purpose of these studies is to identify plant species, or for the autonomous detection of multiple leaves from small seedlings under greenhouse conditions. Machine vision-based detection of individual leaves and challenges presented by overlapping leaves on a developed plant canopy using depth perception properties under natural outdoor conditions is yet to be reported. Stereo vision has recently emerged for use in a variety of agricultural applications and is expected to provide an accurate method for plant segmentation and identification which can benefit from depth properties and robustness. This thesis presents a plant leaf extraction algorithm using a stereo vision sensor. This algorithm is used on multiple leaf segmentation and overlapping leaves separation using a combination of image features, specifically colour, shape and depth. The separation between the connected and the overlapping leaves relies on the measurement of the discontinuity in depth gradient for the disparity maps. Two techniques have been developed to implement this task based on global and local measurement. A geometrical plane from each segmented leaf can be extracted and used to parameterise a 3D model of the plant image and to measure the inclination angle of each individual leaf. The stem and branch segmentation and counting method was developed based on the vesselness measure and Hough transform technique. Furthermore, a method for reconstructing the segmented parts of hibiscus plants is presented and a 2.5D model is generated for the plant. Experimental tests were conducted with two different selected plants: cotton of different sizes, and hibiscus, in an outdoor environment under varying light conditions. The proposed algorithm was evaluated using 272 cotton and hibiscus plant images. The results show an observed enhancement in leaf detection when utilising depth features, where many leaves in various positions and shapes (single, touching and overlapping) were detected successfully. Depth properties were more effective in separating between occluded and overlapping leaves with a high separation rate of 84% and these can be detected automatically without adding any artificial tags on the leaf boundaries. The results exhibit an acceptable segmentation rate of 78% for individual plant leaves thereby differentiating the leaves from their complex backgrounds and from each other. The results present almost identical performance for both species under various lighting and environmental conditions. For the stem and branch detection algorithm, experimental tests were conducted on 64 colour images of both species under different environmental conditions. The results show higher stem and branch segmentation rates for hibiscus indoor images (82%) compared to hibiscus outdoor images (49.5%) and cotton images (21%). The segmentation and counting of plant features could provide accurate estimation about plant growth parameters which can be beneficial for many agricultural tasks and applications

Grafting as a Sustainable Means for Securing Yield Stability and Quality in Vegetable Crops

Vegetable growers around the world only collect, on average, half of the yield they would obtain under optimal conditions, known as yield potential. It is estimated that 60–70% of the yield gap is attributable to abiotic factors such as salinity, drought, suboptimal temperatures, nutritional deficiencies, flooding, waterlogging, heavy metals contamination, adverse soil pH and organic pollutants, while the remaining 30–40% is due to biotic factors, especially soilborne pathogens, foliar pathogens, arthropods and weeds. Under climate change forecasts, the pressure of biotic/abiotic stressors on yield is expected to rise and challenge further global food security. To meet global demand, several solutions have been proposed, focusing on the breeding of varieties with greater yield potential, but this one-size-fits-all solution leads to limited benefits. In order to overcome the current situation, grafting of elite scion varieties onto vigorous rootstock varieties has been suggested as one of the most promising drives towards further yield stability. Specifically, the implementation of suitable rootstock × scion × environment combinations in Solanaceous (tomato, eggplant, pepper) and Cucurbitaceous (melon, watermelon, melon) high-value crops represents an untapped opportunity to secure yield stability and reliability under biotic/abiotic stresses. This Special Issue invites Original Research, Technology Reports, Methods, Opinions, Perspectives, Invited Reviews and Mini Reviews dissecting grafting as a sustainable agro technology for enhancing tolerance to abiotic stresses and reducing disease damage. In addition, the following are of interest: potential contributions dealing with genetic resources for rootstock breeding, practices and technologies of rootstock breeding, and rootstock–scion signaling, as well as the physiological and molecular mechanisms underlying graft compatibility. In addition, the effect of grafting on vegetable quality, practical applications and nursery management of grafted seedlings and specialty crops (e.g. artichoke and bean) will be considered within the general scope of the Special Issue. We highly believe that this compilation of high standard scientific papers on the principles and practices of vegetable grafting will foster discussions within this important field

Proceedings of the European Conference on Agricultural Engineering AgEng2021

This proceedings book results from the AgEng2021 Agricultural Engineering Conference under auspices of the European Society of Agricultural Engineers, held in an online format based on the University of Évora, Portugal, from 4 to 8 July 2021. This book contains the full papers of a selection of abstracts that were the base for the oral presentations and posters presented at the conference. Presentations were distributed in eleven thematic areas: Artificial Intelligence, data processing and management; Automation, robotics and sensor technology; Circular Economy; Education and Rural development; Energy and bioenergy; Integrated and sustainable Farming systems; New application technologies and mechanisation; Post-harvest technologies; Smart farming / Precision agriculture; Soil, land and water engineering; Sustainable production in Farm buildings

Genetic Glass Ceilings

As the world’s population rises to an expected ten billion in the next few generations, the challenges of feeding humanity and maintaining an ecological balance will dramatically increase. Today we rely on just four crops for 80 percent of all consumed calories: wheat, rice, corn, and soybeans. Indeed, reliance on these four crops may also mean we are one global plant disease outbreak away from major famine. In this revolutionary and controversial book, Jonathan Gressel argues that alternative plant crops lack the genetic diversity necessary for wider domestication and that even the Big Four have reached a “genetic glass ceiling”: no matter how much they are bred, there is simply not enough genetic diversity available to significantly improve their agricultural value. Gressel points the way through the glass ceiling by advocating transgenics—a technique where genes from one species are transferred to another. He maintains that with simple safeguards the technique is a safe solution to the genetic glass ceiling conundrum. Analyzing alternative crops—including palm oil, papaya, buckwheat, tef, and sorghum—Gressel demonstrates how gene manipulation could enhance their potential for widespread domestication and reduce our dependency on the Big Four. He also describes a number of ecological benefits that could be derived with the aid of transgenics. A compelling synthesis of ideas from agronomy, medicine, breeding, physiology, population genetics, molecular biology, and biotechnology, Genetic Glass Ceilings presents transgenics as an inevitable and desperately necessary approach to securing and diversifying the world's food supply

The Sustainability of Agro-Food and Natural Resource Systems in the Mediterranean Basin

Agriculture; Food Science; Environmental Science and Engineerin