Modelling cassava production and pest management under biotic and abiotic constraints.

We summarise modelling studies of the most economically important cassava diseases and arthropods, highlighting research gaps where modelling can contribute to the better management of these in the areas of surveillance, control, and host-pest dynamics understanding the effects of climate change and future challenges in modelling. For over 30 years, experimental and theoretical studies have sought to better understand the epidemiology of cassava diseases and arthropods that affect production and lead to considerable yield loss, to detect and control them more effectively. In this review, we consider the contribution of modelling studies to that understanding. We summarise studies of the most economically important cassava pests, including cassava mosaic disease, cassava brown streak disease, the cassava mealybug, and the cassava green mite. We focus on conceptual models of system dynamics rather than statistical methods. Through our analysis we identified areas where modelling has contributed and areas where modelling can improve and further contribute. Firstly, we identify research challenges in the modelling developed for the surveillance, detection and control of cassava pests, and propose approaches to overcome these. We then look at the contributions that modelling has accomplished in the understanding of the interaction and dynamics of cassava and its' pests, highlighting success stories and areas where improvement is needed. Thirdly, we look at the possibility that novel modelling applications can achieve to provide insights into the impacts and uncertainties of climate change. Finally, we identify research gaps, challenges, and opportunities where modelling can develop and contribute for the management of cassava pests, highlighting the recent advances in understanding molecular mechanisms of plant defence

Computational Approaches Based On Image Processing for Automated Disease Identification On Chili Leaf Images: A Review

Chili, an important crop whose fruit is used as a spice, is significantly hampered by the existence of chili diseases. While these diseases pose a significant concern to farmers since they impair the supply of spices to the market, they can be managed and monitored to lessen their impact. Therefore, identifying chili diseases using a pertinent approach is of enormous importance. Over the years, the growth of computational approaches based on image processing has found its application in automated disease identification, leading to the availability of a reliable monitoring tool that produces promising findings for the chili. Numerous research papers on identifying chili diseases using the approaches have been published. Still, to the best knowledge of the author, there has not been a proper attempt to analyze these papers to describe the many steps of diagnosis, including pre-processing, segmentation, extraction of features, as well as identification techniques. Thus, a total of 50 research paper publications on the identification of chili diseases, with publication dates spanning from 2013 to 2021, are reviewed in this paper. Through the findings in this paper, it becomes feasible to comprehend the development trend for the application of computational approaches based on image processing in the identification of chili diseases, as well as the challenges and future directions that require attention from the present research community.&nbsp

Divergences for prototype-based classification and causal structure discovery:Theory and application to natural datasets

Dit proefschrift bestaat uit twee delen. In het eerste deel beschrijven we hoe de op prototypen gebaseerde classificator LVQ uitgebreid kan worden door gebruik te maken van maten uit de informatie theorie. Daarnaast vergelijken we verschillende manieren van datarepresentatie in deze LVQ configuratie, in dit geval histogrammen van foto’s, SIFT- en SURF-kenmerken. We tonen hoe hiervoor een enkele gecombineerde afstandsmaat kan worden geformuleerd, door de afzonderlijke afstandsmaten samen te nemen. In het tweede deel onderzoeken we het vinden van causale verbanden en toepassingen op problemen die uit het leven zijn gegrepen. Daarnaast verkennen we de combinatie met relevantie leren in LVQ en tonen we enkele toepassingen

All India Co-ordinated Research Project on Biological Control of Crop Pests

Not AvailableSurveys were undertaken to document the fauna of insects, spiders and entomopathogenic nematodesacross India despite the travel restrictions due to COVID-19. The expeditions undertaken yielded several species of natural enemies viz.,Chalcididae (66.32%), Eulophidae (19.94%), Pteromalidae (4.14%) and Encyrtidae (3.37%) of Hymenoptera and 14 species of trichogrammatids representing 7 genera. The predominant genera of hymenopteran insect parasitoids were identified as Dirhinus Dalman (30.47%) followed by Brachymeria Westwood (27.73%), Hockeria Walker (22.27%) and Antrocephalus Kirby (18.75%). Revisionary studies of the braconid parasitoid, Apanteles sp. ater-group including subgroup eublemmae of the genus (Hymenoptera: Braconidae) of the Oriental region was carried out with an illustrated key, in which a total of 97 species were recorded and illustrated. Three species of tachinid flies, Peribaea orbata on larva of Spodoptera litura, Halidaia luteicornis on larva of Parnara sp., Sturmiopsis inferens on larva of Sesamia inferens and Carcelia sp. from the larvae of Helicoverpa armigera (Noctuidae) were identified and described. The spider fauna of rice ecosystem was documented, where six species of long jawed orb weaver, Tetragnatha species have been described of which T. keyserlingi was the predominant species across the surveyed locations in Tamil Nadu. The species, Tetragnathanitens collected from Tamil Nadu and Telangana was the first report from India. The spitting spider, Scytodes fusca Walckenaer of family Scyotidae was redescribed with documentation of variations in the vulval pattern of the female and theory about the introduction of this Pantropical species to India.Not Availabl

Root, Tuber and Banana Food System Innovations

This open access book describes recent innovations in food systems based on root, tuber and banana crops in developing countries. These innovations respond to many of the challenges facing these vital crops, linked to their vegetative seed and bulky and perishable produce. The innovations create value, food, jobs and new sources of income while improving the wellbeing and quality of life of their users. Women are often key players in the production, processing and marketing of roots, tubers and bananas, so successful innovation needs to consider gender. These crops and their value chains have long been neglected by research and development, hence this book contributes to filling in the gap. The book features many outcomes of the CGIAR Research Program in Roots, Tubers and Banana (RTB), which operated from 2012-21, encompassing many tropical countries, academic and industry partners, multiple crops, and major initiatives. It describes the successful innovation model developed by RTB that brings together diverse partners and organizations, to create value for the end users and to generate positive economic and social outcomes. RTB has accelerated the scaling of innovations to reach many end users cost effectively. Though most of the book’s examples and insights are from Africa, they can be applied worldwide. The book will be useful for decision makers designing policies to scale up agricultural solutions, for researchers and extension specialists seeking practical ideas, and for scholars of innovation

Case studies of Roots, Tubers and Bananas seed systems.

The seed systems of RTB (root, tuber, and banana) crops are unique because they are propagated from vegetative parts of the plant, not from true seed. RTB seed is thus bulkier, more perishable, and more subject to the attacks of pests and diseases than is true seed. Because of this, there is often a gap between potential and real crop yields, which seed interventions seek to narrow. Seed systems are formal or informal networks of people and organizations that produce, plant, and distribute seed. Informal systems may deliver low quality seed, but not always. This book describes 13 RTB seed system interventions, using a framework based on the concepts of seed availability, access, and quality. The 13 case studies included (1) a potato-growers’ association in Ecuador, (2) a hydroponic seed potato in Peru, (3) a yam seed technology in Nigeria, (4) a banana and plantain project in Ghana, (5) a sweetpotato seed project in Tanzania and (6) one in Rwanda, (7) a seed potato system in Kenya, (8) cassava in Nicaragua, (9) seed potato in Malawi, (10) disease-resistant cassava varieties in seven African countries, (11) a tissue culture banana project, (12) an emergency plantain and banana project in East Africa, and (13) a large cassava seed project in six African countries

Root, Tuber and Banana Food System Innovations

This open access book describes recent innovations in food systems based on root, tuber and banana crops in developing countries. These innovations respond to many of the challenges facing these vital crops, linked to their vegetative seed and bulky and perishable produce. The innovations create value, food, jobs and new sources of income while improving the wellbeing and quality of life of their users. Women are often key players in the production, processing and marketing of roots, tubers and bananas, so successful innovation needs to consider gender. These crops and their value chains have long been neglected by research and development, hence this book contributes to filling in the gap. The book features many outcomes of the CGIAR Research Program in Roots, Tubers and Banana (RTB), which operated from 2012-21, encompassing many tropical countries, academic and industry partners, multiple crops, and major initiatives. It describes the successful innovation model developed by RTB that brings together diverse partners and organizations, to create value for the end users and to generate positive economic and social outcomes. RTB has accelerated the scaling of innovations to reach many end users cost effectively. Though most of the book’s examples and insights are from Africa, they can be applied worldwide. The book will be useful for decision makers designing policies to scale up agricultural solutions, for researchers and extension specialists seeking practical ideas, and for scholars of innovation