Unpublished flow cytometry results (October 1997) suggest that PYR 1090.001 may be diploid. -- J. PostmanNotes from February, 2003 regarding ploidy:
Richard Bell (the source of this accession) in Kearneysville, WV wrote to Anna Voordeckers: We received budwood of the pear cultivar Ewart from Fred Hough in 1963. The clone was marked as a tetraploid (4x). Do you ... know how the ploidy level was determined. Was the original Ewart cultivar a tetraploid, or just this one clone
Response: From Cream Ridge Fruit Research and Extension, Wednesday, February 12, 2003 to Richard Bell: The only reference I can find for 'Ewart' was that we received scions on 3/17/47 from the NY Fruit Testing Association. It did not mention anything about tetraploid. It was used as a female in a cross in 1960. -- Anna Voordeckers (had been Frederic Hough's technician at Rutgers).