Warwick Crop Centre www.warwick.ac.uk/go/wcc

1. Exploiting Next Generation Sequencing to investigate the genetics of parsnip root disease and develop a marker assisted breeding strategy Lauren Chappell (L.H.K.Chappell@Warwick.ac.uk) Superivsors: Dr Guy Barker1, Dr John Clarkson1, Dr Graham Teakle1, Mrs Sue Kennedy2 1Warwick Crop Centre, School of Life Sciences, University of Warwick, Wellesbourne, CV35 9EF 2Elsoms Seeds Ltd, Spalding, Lincolnshire, PE11 1QG • Aims • This project aims to develop genetic marker technologies to identify and exploit these sources of resistance. • Rapid resistance screening methods and a better understanding of canker pathogens is also to be investigated. • Introduction • Pastinaca sativa (parsnips) are a speciality crop in the UK, covering an area of 3100ha and a value of £64M annually. • Major constraint to production is crop losses associated with root canker diseases caused by fungal pathogens such as Itersonilia and Mycocentrospora spp. • Itersonilia pastinacae(I.pastinacae) is a seed borne pathogen that produces ballistospores and chlamydospores that results in both foliar and root symptoms. • Mycocentrosporaacerina (M. acerina) is a soil borne pathogen that produces long living chlamydospores that result in liquorice rot root symptoms. • Some resistance to parsnip canker exists but is difficult to select for using traditional breeding methods. • Symptom Data • Diseased roots collected from UK locations and classified by symptom appearance. • Isolations of tissue made from each root and mycelial colonies identified through spore morphology and ITS sequencing Itersonilia infected parsnip leaf Itersonilia infected parsnip seedlings Parsnip canker • Itersonilia pastinacaeresistance assay • P. Sativa lines were artificially inoculated with Itersonilia and. • Developing lesions were measured to assess current resistance. • Results indicate range of resistance across P. sativa lines. • Identification of number (%) and types of pathogens isolated from diseased P. sativa roots. Symptom examples L-R: Itersonilia, Pythium, Other, Mycocentrospora, Fusarium, Cylindrocarpon. • Future Work • Further P. sativa lines will be screened for resistance to other canker pathogens such as Mycocentrospora. • Itersonilia pathogenicity assays will be developed • Whole Genome Sequencing will be carried out on Itersonilia isolates to develop a DNA-based diagnostic test. • Develop genetic markers for QTL mapping based on genotypic and phenotypic data from P.sativa line resistance screening. Resistance Itersonilia inoculated parsnip root Susceptible Itersonilia inoculated parsnip root Warwick Crop Centre www.warwick.ac.uk/go/wcc