Performance of Inter- and Intraprovenance Crosses of Jack Pine in Central Wisconsin

1991

S. 124-130

2 Abb., 4 Tab., 28 Lit. Ang.

Unselbständiges Werk

200051269

Inter- und intraprovenance crosses of jack pine (Pinus banksiana Lamb.) from six provenances across the natural range were planted in central Wisconsin and evaluated at age nine for height and pine-oak gall rust caused by Cronartium quercum. Survival was greater than 88% for all inter- and intraprovenance combinations except the intraprovenance cross from Big River, Saskatchewan (77% survival). Interprovenance hybrids showed no increased resistance to pine-oak gall rust infection. Trees representing provenances from Fife Lake Michigan, and Petawawa Plains, Ontario, had higher rates of rust infection than trees representing other provenances. Trees representing provenances far from the planting site: Durell Island (Nova Scotia), Fort Smith (Northwest Territories), Big River (Saskatchewan); were shorter than provenances from the Lake States region: Mosinee (Wisconsin), Fife Lake (Michigan), Petawawa Plains (Ontario). Interprovenance hybrids had heights similar to the respective midparent values. No evidence of heterosis was found, suggesting that directional dominance in gene actions is lacking. Variance component analysis revealed some large provenance effects but little or no family effect. The lack of family effect found is likely due to the mating design being insufficient to detect family differences. Interprovenance hybridization may be a useful technique for broadening the genetic base to increase population size, but heterosis is uncommon and adaptability imposes limits on the extent to which distant provenances can be used without sacrificing yield.