Breeding eastern white pine for blister rust resistance: A review of progress in Ontario

Abstract

White pine blister rust (caused by Cronartium ribicola J.C. Fisch.) is a primary cause of poor survival and growth of eastern white pine (Pinus strobus L.) and has contributed to the species' decline across its range. Genetic resistance to C. ribicola is generally weak in eastern white pine, possibly owing to the absence of meaningful resistance alleles. Integrating major resistance genes from Eurasian 5-needle pine species to P. strobus has been demonstrated to be effective through traditional plant breeding approaches. This paper provides a review of progress after more than half a century of breeding and testing in Ontario.Key words: Pinus strobus, white pine blister rust, genetic resistance, interspecific hybridization RÉSUMÉ La rouille vésiculeuse du pin blanc (provoquée par Cronartium ribicola J.C. Fisch.) constitue la cause principale de la grande mortalité et de la faible croissance chez le pin blanc de l'Est (Pinus strobus L.) et a contribué au déclin de l' espèce dans toute son aire de distribution. La résistance génétique au C. ribicola est généralement faible chez le pin blanc de l'Est, possiblement suite à l'absence d'allèles pouvant offrir une résistance significative. L'intégration de gènes de résistance importante tirés d'une espèce eurasienne de pin à cinq aiguilles par le P. strobus s' est avéré être efficace selon les approches habituelles d'hybridation des plantes. Cet article présente une révision des progrès réalisés après plus d'un demi-siècle d'hybridation et d' essai en Ontario.Mots clés : Pinus strobus, rouille vésiculeuse du pin blanc, résistance génétique, hybridation interspécifique

Genetic Resistance to Fusiform Rust in Southern Pines and White Pine Blister Rust in White Pines—A Contrasting Tale of Two Rust Pathosystems—Current Status and Future Prospects

“…Very few studies have evaluated field performance of resistance in eastern white pine and results have been inconsistent [80] with resistant stock both performing better and worse than controls. Larger field trials are underway, but so far progress has been far less promising than with other species [81,82].…”

New hosts and differential susceptibility of five-needle pine species to Dooks needle blight (Lophophacidium dooksii)

“…Strong resistance to white pine blister rust was found in interspecific hybrids between P. strobus and P. parviflora (Lu & Derbowka, 2009). Because this species was not infected, using P. parviflora as a major blister rust resistance gene donor may also enhance resistance to needle blight.…”

“…Pinus peuce is often planted as an ornamental tree worldwide (Lines, 1985;Merrill et al, 1996;Mortenson & Mack, 2006). This pine hybridizes easily with P. strobus and P. monticola and usually produces abundant viable seed (Lu & Derbowka, 2009); therefore, it has been used in genetic trials to provide blister rust resistance to these white pine species (Kriebel, 1983;Blada, 2000;Sniezko et al, 2008). Few diseases and little related damage are reported for P. peuce in its native range (Lines, 1985); however, this pine from the Balkans appears highly susceptible to infection and damage from this needle blight.…”

“…Fisch.) using an introgressive hybridization approach (Lu & Derbowka, 2009). The archive, consisting of nine fiveneedle pine species from Eurasia and North America and a number of interspecific hybrids among 11 five-needle pine species, comprised 457 trees at 3 × 3 m spacing.…”

“…Pinus wallichiana is capable of producing viable hybrid seeds with P. strobus or P. monticola, although it is less successful than P. peuce (Critchfield, 1986). Because of proven strong resistance to white pine blister rust in some of its interspecific hybrids with P. strobus in the past (Heimburger, 1972;Lu et al, 2005), P. wallichiana trees were selected and used as major resistance gene donors to P. strobus (Lu & Derbowka, 2009). Interestingly, a number of selected individuals in the genetic archive that stemmed from backcrosses of P. strobus with P. wallichiana at various degrees of introgression to P. strobus did not show symptoms of this needle blight.…”