Christmas Tree Research Center, Dalhousie Agricultural Campus, Bible Hill, Nova Scotia, Canada, B2N 5E3.
Journal of Applied Horticulture, 2014, volume 16, issue 1, pages 29-31.
Abstract: Balsam fir trees are the most popular choice for Christmas trees in Atlantic Canada and a major export commodity, despite postharvest needle abscission challenging the industry's viability. The objective of this study was to determine if any needle or branch biophysical and/or morphological characteristics may be linked with needle abscission resistance (NAR) in balsam fir. A total of 17 different parameters were measured in branches of clones that belonged to low, medium, or high needle abscission resistant groups. Of the parameters measured, branch diameter, initial mass, needle density, break strength, and needle retention duration were significantly (P < 0.05) different between genotype groups. It was found that high NAR genotypes had a 9.1% smaller diameter, 25.0% lower initial mass, 33.2% lower needle break strength, 32.4% lower needle density, and 91% longer needle retention than low NAR clones. Of these factors, needle density was the best predictor for needle retention duration (R2 = 47%). Identification of these parameters is an important first step to understand physiological and genetic linkage for development of Christmas trees with high NAR.