PT - JOURNAL ARTICLE AU - Astrid Forneck AU - Kevin S. Powell AU - M. Andrew Walker TI - Scientific Opinion: Improving the Definition of Grape Phylloxera Biotypes and Standardizing Biotype Screening Protocols AID - 10.5344/ajev.2016.15106 DP - 2016 Oct 01 TA - American Journal of Enology and Viticulture PG - 371--376 VI - 67 IP - 4 4099 - http://www.ajevonline.org/content/67/4/371.short 4100 - http://www.ajevonline.org/content/67/4/371.full SO - Am J Enol Vitic.2016 Oct 01; 67 AB - Grape phylloxera biotypes are defined by their specific performance on, or preference for, a particular host (e.g., feeding on a particular rootstock). Numerous studies have phenotyped phylloxera biotypes, particularly with regard to their performance on various hosts, but the results are difficult to compare because there is neither a homogenous nomenclature nor a standardized protocol for phenotyping. To improve communication within the scientific community, we offer a simplified phylloxera biotype classification to allow clear data interpretation and effective communication. We also introduce the standard techniques employed for phylloxera phenotyping and discuss their advantages and disadvantages.