Micropropagation and field evaluation of the pear (Pyrus communis L.) 'IGE 2002', a new selection of the cultivar Dr. Jules Guyot

Abstract

A new spontaneous mutation of the pear variety Dr. Jules Guyot, named 'IGE 2002', was selected from a pear growing area in Catalonia. The clone was established in vitro from a 40-year-old tree, a highly recalcitrant material unable to root by cuttings. An in vitro micropropagation protocol, with an average multiplication rate of 5, a 90% rooting, and an acclimation of 79% of the plantlets, was defined. Self-rooted plants were grown in two experimental stations, covering two distinct fruit growing areas. The main agronomic characteristics of the clone 'IGE 2002' were evaluated during six seasons, 1997 to 2002. Blooming and harvest period were at a similar time than 'Dr. Jules Guyot'. Soluble solids concentration and acidity are also similar to 'Dr. Jules Guyot'. However, at the same harvest time, a lower fruit firmness of 'IGE 2002' in comparison to 'Dr. Jules Guyot' indicated an advanced ripening. In addition, a finer flesh texture of 'IGE 2002' than 'Dr. Jules Guyot', distinguished the former from the later variety. Important differences between both plot sites were found on cumulative fruit yield, fruit size, and fruit size distribution, of 'IGE 2002' grown on its own roots. However, the site did not affect the fruit quality parameters. Superior fruit yields were associated with higher vigor and yield efficiency of the self-rooted variety.