The knowledge of ecology and epidemiology of rhizomania is particularly useful to understand the means and practices able to limit or avoid its further diffusion. Some promising methods of biological control using coexisting and non-pathogenic organisms could potentially help improve the action of the not completely effective genetic resistances. This integrated protection would be valuable, especially in the even more frequent development of resistance-breaking strains in the BNYVV, where the known types of resistance, alone or in combination, seem to have lost part of their original ability to protect the crop. Therefore, further efforts will be needed to discover new traits likely still present in the wild species of the genus Beta. The availability of large collections of germplasm stored in the International Beta gene-banks should ensure the enhanced efficiency of genetic resistance by means of conventional and marker-assisted selection methods. Some almost immune transgenic varieties seem already to be waiting for release where and when it will be possible. The introduction chapter describes briefly the sugar beet crop, the more common diseases, and the damage caused by rhizomania. The following chapters discuss biological properties of the causal virus, BNYVV, and its vector, Polymyxa betae, and their interactions with the environment and the host-plant. In particular, the great advances in research of the molecular biology of BNYVV should be noteworthy, which have been established by a wide range of the most modern methods. Recent work focused on the genetic diversity and evolution of BNYVV is moving forward our understanding of the dramatic worldwide epidemics of rhizomania. Newly developed molecular techniques also lead to practical applications, such as quantification of inoculum in ecological and epidemiological research.
This book, now in its second edition, provides researchers and operators a complete description of all aspects regarding the wild ancestor of sugar beet. The possibility of crossing modern crops with the ancestors from which they are derived in order to recover some traits lost through domestication is increasingly attracting interest. The selective process implemented by the first growers led to the elimination of features not considered useful at the time. Yet some of these lost traits have now become very important. In fact, in many areas sugar beet cultivation would now be impossible without the transfer of some genetic resistances from Beta maritima, the crop's ancestor. Moreover, the isolation of such traits is becoming increasingly critical with regard to current and future environmental and economic considerations on e.g. the use of pesticides. This second edition replaces certain photographs and has been updated to reflect the latest advances and findings. One chapter and several sections have been rewritten, and significant revisions have been made throughout the text. The new techniques provide breeders with massively improved analytical means for the safest and fastest selection procedures. Not only will these techniques allow Beta maritima to take on a far greater role as a source of favorable traits; the relative ease with which these characteristics can be transferred will also make it possible to use the germplasm of the whole genus Beta and Patellifolia, which to date has been highly complex, if not impossible, due to the difficulties of hybridization.
Along the undisturbed shores, especially of the Mediterranean Sea and the European North Atlantic Ocean, is a quite widespread plant called Beta maritima by botanists, or more commonly sea beet. Nothing, for the inexperienced observer's eye, distinguishes it from surrounding wild vegetation. Despite its inconspicuous and nearly invisible flowers, the plant has had and will have invaluable economic and scientific importance. Indeed, according to Linnè, it is considered "the progenitor of the beet crops possibly born from Beta maritima in some foreign country". Recent molecular research confirmed this lineage. Selection applied after domestication has created many cultivated types with different destinations. The wild plant always has been harvested and used both for food and as a medicinal herb. Sea beet crosses easily with the cultivated types. This facilitates the transmission of genetic traits lost during domestication, which selection processes aimed only at features immediately useful to farmers and consumers may have depleted. Indeed, as with several crop wild relatives, Beta maritima has been successfully used to improve cultivated beet's genetic resistances against many diseases and pests. In fact, sugar beet cultivation currently would be impossible in many countries without the recovery of traits preserved in the wild germplasm. Dr. Enrico Biancardi graduated from Bologna University. From 1977 until 2009, he was involved in sugar beet breeding activity by the Istituto Sperimentale per le Colture Industriali (ISCI) formerly Stazione Sperimentale di Bieticoltura (Rovigo, Italy), where he released rhizomania and cercospora resistant germplasm and collected seeds of Mediterranean sea beet populations as a genetic resource for breeding and ex situ conservation. Retired since 2009, he still collaborates with several working breeders, in particular, at the USDA Agricultural Research Stations, at the Chinese Academy of Agricultural Science (CAAS), and at the Athens University (AUA). He has edited books, books chapters and authored more than 150 papers.Dr. Lee Panella is a plant breeder and geneticist with the USDA-ARS at Fort Collins, Colorado. He earned his B.S. in Crop and Soil Science from Michigan State University, an M.S. in Plant Breeding from Texas A&M University, and a Ph.D. in genetics from the University of California at Davis. His research focus is developing disease resistant germplasm using sugar beet wild relatives. He is chairman of the USDA-ARS Sugar Beet Crop Germplasm Committee and has collected and worked extensively with sea beet. Dr. Robert T. Lewellen was raised on a ranch in Eastern Oregon and obtained a B.S. in Crop Science from Oregon State University followed by a Ph.D. from Montana State University in Genetics. From 1966 to 2008 he was a research geneticist for the USDA-ARS at Salinas, California, where he studied the genetics of sugar beet and as a plant breeder, often used sea beet as a genetic source to produce many pest and disease resistant sugar beet germplasm and parental lines, while authoring more than 100 publications.
