Authors: Ross Cameron Richard HarrisonMurray Michael Fordham Heather Judd Yannick Ford Tim Marks Rodney Edmondson
Publish Date: 2003/03/06
Volume: 17, Issue: 5, Pages: 451-462
Abstract
The relationship between shoot growth and rooting was examined in two difficultto root amenity trees Syringa vulgaris L cv Charles Joly and Corylus avellana L cv Aurea A range of treatments reflecting severity of pruning was imposed on fieldgrown stock prior to bud break To minimise variation due to the numbers of buds that developed under different treatments bud number was restricted to 30 per plant Leafy cuttings were harvested at different stages of the active growth phase of each species With Syringa rooting decreased with later harvests but loss of rooting potential was delayed in cuttings collected from the most severe pruning treatment Rooting potential was associated with the extent of postexcision shoot growth on the cutting but regression analyses indicated that this relationship could not entirely explain the loss of rooting with time nor the effects due to pruning Similarly in Corylus rooting was promoted by severe pruning but the relationship between apical growth on the cutting and rooting was weaker than in Syringa and only at the last harvest did growth play a critical role in determining rooting Another unusual factor of the last harvest of Corylus was a bimodal distribution of roots per cutting with very few rooted cuttings having less than five roots This implies that for this harvest at least the potential of an individual cutting to root is probably not limited by the number of potential rooting sites
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