Establishment and growth of sandalwood (Santalum spicatum) in south-western Australia: the influence of host species.

摘要

The performance was examined of sandalwood (Santalum spicatum) parasitizing 2 N2-fixing woody hosts (Acacia acuminata and Allocasuarina huegeliana) and a non N2-fixing host (Eucalyptus loxophleba subsp. loxophleba) on farmland at Kwobrup, WesternAustralia. The host seedlings were planted in 1991, and the S. spicatum was direct sown at host age 5 years. Survival and growth of the S. spicatum were assessed at age 3 years. S. spicatum survival was significantly higher when planted next to Acacia acuminata (86%) than Allocasuarina huegeliana (29%), and all seedlings next to E. loxophleba subsp. loxophleba died within 2 years of establishment. Mean height and stem diameter of S. spicatum parasitizing Acacia acuminata were significantly greater thanthose parasitizing Allocasuarina huegeliana. The initial presence of S. spicatum did not reduce host survival or growth. The foliar N and K concentrations, and the K:Ca ratio were significantly higher in S. spicatum parasitizing Acacia acuminata than Allocasuarina huegeliana. However, the S. spicatum attached to Allocasuarina huegeliana had significantly higher concentrations of foliar P, Ca and Mg. The leaf and stem water potentials (PSIleaf, PSIstem) of S. spicatum trees were the same or significantlylower than those of their paired hosts, at pre-dawn and midday. In February-March 1999, the stem water potential of the S. spicatum-Acacia acuminata pairing were significantly lower than that of the S. spicatum-Allocasuarina huegeliana pairing.