Quince is used as a dwarfing rootstock for pear, depending on the scion desired and characteristics of the production area. Regarding pear production in Europe, Wertheim, a plant breeder in the Netherlands, discusses the use of quince as a dwarfing rootstock in high-density European-pear (Pyrus communis) plantings where small trees are desired. He characterizes good dwarfing rootstocks as those which induces early, regular cropping, good fruit size and quality, are easily propagated, and sufficiently cold hardy (2002). In a discussion of canopy management in European pear orchards, Sansavini and Musacchi (1994) indicate that quince rootstocks are highly suited to high-density pear  plantings of cv. Doyenne du Comice and ‘Blanquilla’, inducing the desired qualities of early cropping and reduced vigor.

In the US, quince susceptibility to fireblight, winter injury and low tolerance for alkaline soils have limited its use as a pear rootstock. However, as indicated above, quince is a good rootstock for the Comice pear, demonstrating high yield efficiency and vigor. In the UC Pear Production and Handling Manual (2007), Reil reports that Comice pear on Quince BA-29  rootstock produces a favorable short wide fruit with a large diameter, while scions of cv. Winter Nelis, Bartlett and the Old Home crosses produce a less desirable long narrow fruit. He characterizes rootstock Quince BA-29 as tolerant of heavy soils, wet soil, and root lesion nematode, with good resistance to crown gall and moderate tolerance to pear decline. Less desirable traits of the rootstock include low susceptibility to chlorosis and fire blight, and a fair anchorage rating, due to the quince shallow root system. (Reil et al. 2007).

A factor which limits the broad use of quince as a pear rootstock in the US  is poor compatibility with the popular scions Bartlett and Bosc, necessitating an interstem graft with a compatible pear cultivar such as Comice or Hardy. (Elkins and DeJong  2002).

Quince Rootstock Cultivars & Breeding Programs

Early in the 1900s, researchers at East Malling in England collected quince rootstocks from a number of nurseries throughout Europe, including those from the Angers region of France where quince had been used as a pear rootstock for centuries. The East Malling group designated rootstock clones with letters of the alphabet: Quince A through G. Quince rootstock clones now available in the United States include ‘EM  Quince A’ and ‘EM Quince C’  from East Malling (EM) and ‘Provence Quince’ (=Quince BA 29-C) from France (Postman 2009), typically paired with scion cv Comice.

Breeding programs continue in the research and development of quince rootstocks compatible with various pear scions and pear production areas.  In the US, breeding programs are associated with Washington State University., Oregon State University, the USDA-ARS National Clonal Germplasm Repository, the University of California, and  the USDA-ARS Appalachian Fruit Research Station, WV. Pear Genomics is a new website associated with these breeding programs.

References

Elkins, R.B. and DeJong, T.M. 2002. Effect of training system and rootstock on growth and productivity of Golden Russet®Bosc pear trees. Acta Hort. (ISHS) 596:603-607.

Postman, Joseph. 2009. Cydonia oblonga: The Unappreciated Quince. 2009 - Arnoldia 67(1):2-9.

Reil, W.O., Ireland, J., Elkins, R.B. 2007. Propagation and Rootstock Selection. Pages 33-44. Pear Production and Handling Manual. University of California Agriculture and Natural Resources Publication 3483..

Sansavini, S. and Musacchi, S. 1994. Canopy architecture, training, and pruning in the modern European pear orchards: An Overivew. Acta Hort. (ISHS) 367:152-172.

Wertheim. 2002. Rootstocks for European Pear: a Review. Proc.8th Internat’l Symposium on Pear
Eds. L. Corelli-Grappadelli et al. Acta Hort 596, ISHS 2002: 299-309.