In this article:
This work continues from an earlier study on pruning and the findings of the earlier paper are extended with particular regard to the level of cropping which can be considered overcropping.
When sultana vines were pruned to from three to eight 14-bud canes each year for 14 years there was in every season a linear relation between number of canes retained and weight of fruit harvested.
There were some departures from the relationship between weight per cane and mean yield for the season that are suggestive of a slight biennial bearing effect.
Smaller experiments on three sites comparing pruning to 6, 8, 10 and 12 canes per vine showed that a Iinear relation between number of canes and weight of fruit also held over this range for the four seasons studied, with no interaction between pruning treatment and site.
In both cases there were significant differences in yield between individual vines within the pruning treatments over the period of the trials and these appeared to be at least partly due to internal factors in the vines.
The main conclusion drawn is that the danger of overcropping of sultanas in the Murray Valley is not as serious as was previously thought.
A Comparison of Cropping Levels in the Sultana
1965, Vitis, vol 5, pages 1 – 9
Please note accessing PDF may be slow, thank you.