Articles
THE INFLUENCE OF CALCIUM CHLORIDE RATE AND SPRAY METHOD ON THE CALCIUM CONCENTRATION OF APPLE FRUITS
Treatments in the experiment included a non-treated check, three treatments involving the application of 234 l ha-1 in each of twelve alternate ‘row-middle’ sprays (half sprays) and two treatments at 93.5 1 ha-1. Calcium chloride was sprayed at the higher volume of water at 31.7, 42.3 and 52.8 kg ha-1 year-1. At the lower volume of water, calcium chloride was applied at 31.7 and 42.3 kg ha-1 year-1.
Based on fruit analyses at harvest, none of the treatments significantly influenced the calcium concentration of the peel, the shallow flesh or the conventional flesh sample (peel to vascular bundles). In addition, none of the treatments significantly influenced the N/Ca ratio in any of the fruit analyses.
All of the spray treatments, applied at either 234 or 93.5 l ha-1, significantly reduced the mean number of cork spots per fruit below 0.37 found in the control and were not different from each other.
The highest level found in the treatments was 0.13 while the lowest was 0.04. All of the treatments significantly increased the percentage of fruits with no corking.
Thus, while the control had 75.6 per cent, the treatments resulted in between 92.8 per cent and 97.2 per cent clean fruits.
In addition, the sprays reduced the percentage of fruits that had one or two cork spots per fruit.
While the control treatment had 20 per cent, the sprayed fruit had between 2.6 and 6.7 per cent with one or two cork spots per fruit.
Although none of the sprays influenced fruit weight there was a significant effect of weight on the calcium concentration of the peel and shallow flesh sample and on the N/Ca ratio of the shallow flesh sample.