Yara porfolio approach improves Prune production
Independent trials conducted by the Bureau National Interprofessionnel du Pruneau (BIP) in south west France have shown excellent results from calcium applications to prunes.
In 2007 a Yara programme of 200kg/ha YaraLiva Tropicote applied after flowering and 300 kg/ha Unika Calcium applied at stone hardening was compared to a normal fertilizer programme using 100 kg/ha ammonium nitrate post flowering and 100 kg/ha ammonium nitrate plus 150 kg/ha Unika Kali at stone hardening. The Yara programme gave statistically significant increases in fruit Brix, fresh/dry yield ratio and fruit size. This is important because all these measures affect grower returns from the crop; larger fruit are worth more and higher sugar content means a greater yield of dried prunes from the harvested fresh fruit.
These results come on top of excellent results obtained in 2001 using YaraVita Actiphos Ca (250 g/l P2O5, 420 g/l CaO). Actiphos Ca was applied as a foliar spray at 10 litres/ha on three occasions (4, 8 & 12 leaves). Once again, calcium application gave an increase in fruit size and the fresh/dry yield ratio. There was also gave a significant improvement in the appearance of prunes following their rehydration. The incidence of brown fruit fell from 34% in the control to only 5% in the Actiphos Ca treatment.
The message from these trials is clear: Calcium is a vitally important nutrient for prune production and with YaraLiva and YaraVita products we are uniquely placed to respond and help plum producers maximise their returns.
Author: John Brooks, France
Published: March 2008