Studies on the Importance and Control of Potato Virus X

作者：Frederick Charles Bawden, Basil Kassanis, F. M. Roberts · 发表于：Annals of Applied Biology · 年份：1948 · DOI：10.1111/j.1744-7348.1948.tb07366.x · 被引用次数：58 · 研究领域：Plant Virus Research Studies、Plant Pathogens and Resistance、Plant Disease Resistance and Genetics

The success of seed certification schemes in controlling the aphis‐transmitted viruses that cause leaf roll and rugose mosaic has greatly increased the relative importance of potato virus X, in spite of the value of such schemes in reducing the prevalence of the most virulent strains. Virus X occurs throughout commercial stocks of most varieties and is responsible for many of the uncertainties and difficulties encountered in field inspections, for the production of leaf symptoms by many strains depends on the weather. Also, the predominating virus strain in a stock may change from season to season. Methods of testing for the presence of avirulent strains in potatoes are described. These include transmission to suitable indicator plants, plant‐protection tests, and serological methods. The virus content of different parts of the plant varies widely, but is everywhere high enough for transmission to indicator plants at all times of the year. The virus content of immature tubers is too low to give a precipitin reaction, but extracts from developing sprouts contain nearly as much virus as those from foliage, and can be used reliably. Infection of virus‐free stocks of the varieties Majestic and Arran Banner with four different strains of virus X reduced their yields by amounts varying from 5 to 24%. Scotch Stock Seed Majestic, however, cropped better than the virus‐free seed, and the need for considering additional factors to freedom from viruses when selecting clonal lines for pr...