Potato virus Y (PVY) infects a wide host range mainly within the Solanaceae and is distributed worldwide. PVY is transmitted by more than 40 aphid species in a non persistent manner. Isolates of the PVY species are highly variable at biological, serological and molecular levels. Epidemiological studies have highlighted the emergence of distinct potato PVY variants able to induce necroses on potato tubers. Due to the lack of efficient resistance to PVY isolates inducing necrotic symptoms in cultivated varieties and the plant-to-plant transmission of isolates through the daughter tubers, PVY has become the most economically important virus for the potato industry. The review offers an overview of several decades of research on PVY but also focuses on the latest data obtained by expert on PVY worldwide on the biological characteristics of PVY, interactions between aphids-hosts, its evolution and management. Identified knowledge gaps to understand further PVY biology will be discussed.

Potato improvement by traditional breeding and opprotunities for new technologies; Ac-Ds trasposons mapped near disease resistance loci for targeted tagging in potato; Studies to enhance starch biosynthesis by manipulation of ADP-glucose pyrophsphorylase genes; Control of carbohydrate metabolism in potato tubers; Transgenic potatoes changed in carbohidrate partitioning and allocation; Control of sugar balance in potato tubers; Post-harvest regulation of sucrose accumulation in transgenic potatoes: role and properties of potato tuver UDP-glucose pyrophosphorylase; Post-harvest potato tuver glycerolipid; Functionality of semi-artificial trasnit peptides encoded by gene constructs derived form hte potato gene for granule-bound starch synthase; Potato alternative oxidase: detection of mRNA by PCR and tissue-specific differences in the protein levels; Polyphenol oxidase in potato tubers; Gene expression during early tuber development; Use of ubiquitin promoters for transgene; Regulation of translation in potato tubers in response to environmental stress; Expression of the Brasil nut methuibube-rich protein in transgenic potato plants; Strategies towards introducing resistance to bacterial pathogens in transgenic potatoes; Field performance of transgenic potatoes; Analysis of containment and food safety issues associated with the release of transgenic potatoes.

This book provides a comprehensive look at the field of plant virus evolution. It is the first book ever published on the topic. Individual chapters, written by experts in the field, cover plant virus ecology, emerging viruses, plant viruses that integrate into the host genome, population biology, evolutionary mechanisms and appropriate methods for analysis. It covers RNA viruses, DNA viruses, pararetroviruses and viroids, and presents a number of thought-provoking ideas.

This volume of Advances in Virus Research focuses on mycoviruses. The authors and reviews represent the most current and cutting-edge research in the field. A broad range of research is presented from research experts. Contributions from leading authorities Informs and updates on all the latest developments in the field

Potato (Solanum tuberosum L.) is a staple food in the world. Potato virus Y (PVY; Potyvirus: Potyviridae ) is an important virus that affects yield and quality of potatoes. PVY exists as biologically distinct strains: PVY-N induces systemic veinal necrosis in tobacco, PVY-O causes hypersensitive response (HR) in potato cultivars carrying the Ny gene and PVY-NTN produces necrotic rings on the tubers of sensitive potato cultivars. The vsiRNA profiles of three distinct PVY strains, ordinary (PVY-O), tobacco-veinal necrotic (PVY-N) and tuber-necrotic (PVY-NTN) strains were determined in potato cv. Russet Burbank. The frequency and distribution of vsiRNAs varied among different strains. PVY-NTN infected plants accumulated the highest population of PVY-vsiRNAs in comparison to plants infected with PVY-O and PVY-N. In PVY-infected plants, the 21 nt class was predominant whereas in healthy potato plants 24 nt class had the maximum population. VsiRNAs were derived from every nucleotide position of the PVY genome and certain hotspots were identified which produced relatively more vsiRNAs. Additionally, six novel microRNAs were found in PVY-infected plants. Potato virus S (PVS; Carlavirus: Betaflexiviridae) is another important potato virus distributed worldwide. The outcome of mixed infection of PVS and PVY was studied under controlled conditions in three potato cultivars, Defender, Desiree and Russet Burbank. Results showed that PVS has an antagonistic effect on PVY replication in mixed infection. The antagonistic effect was associated with less severe symptoms in dual infections as well as reduced PVY multiplication. Symptoms of PVS were not visible in Desiree and Russet Burbank plants except Defender which showed bronzing spots on the leaves. PVY symptoms included mosaic, mottling and leaf drop. It was found that the antagonistic effect of PVS on the replication of PVY is independent of host genetic background as the same pattern was found in all three potato cultivars. Potato cultivars such as Desiree carrying the Ny gene show HR to infection with the ordinary strain of PVY. In comparison to Russet Burbank, PVY levels in Desiree decreased with increasing number of days post-inoculation. The HR was found to be specific to PVY-O and was not elicited by infection by PVY-N or PVY-NTN.

This book is open access under a CC BY 4.0 license. This book provides a fresh, updated and science-based perspective on the current status and prospects of the diverse array of topics related to the potato, and was written by distinguished scientists with hands-on global experience in research aspects related to potato. The potato is the third most important global food crop in terms of consumption. Being the only vegetatively propagated species among the world’s main five staple crops creates both issues and opportunities for the potato: on the one hand, this constrains the speed of its geographic expansion and its options for international commercialization and distribution when compared with commodity crops such as maize, wheat or rice. On the other, it provides an effective insulation against speculation and unforeseen spikes in commodity prices, since the potato does not represent a good traded on global markets. These two factors highlight the underappreciated and underrated role of the potato as a dependable nutrition security crop, one that can mitigate turmoil in world food supply and demand and political instability in some developing countries. Increasingly, the global role of the potato has expanded from a profitable crop in developing countries to a crop providing income and nutrition security in developing ones. This book will appeal to academics and students of crop sciences, but also policy makers and other stakeholders involved in the potato and its contribution to humankind’s food security.