EFFECT OF PACLOBUTRAZOL AND PROHEXADIONE-CALCIUM ON SHOOT GROWTH RATE AND GROWTH CONTROL IN ´BLANQUILLA´ AND ´CONFERENCE´ PEAR

The aim of this study was to evaluate the efficacy of applying Cultar and Regalis foliar applications in pear orchards to reduce tree vigour or shoot growth.
Cultar was applied once 15-20 days after full-bloom and Regalis was applied 4 times every 3-4 weeks, commencing when shoots had 2-4 expanded leaves.
Cultar was the more effective for reducing shoot growth because final shoot length was shorter than with Regalis and because growth rates were slightly inferior for Cultar trees.
Prohexadione-Calcium inhibited shoot growth within a few days and it was more rapid than Cultar, which took at least 7 days to reduce shoot growth rate.
The fact that Regalis was quicker at reducing shoot growth rate and that Cultar produced greater reductions in shoot length and shoot growth rate may indicate that the best option would involve combining the use of these two bioregulators to reduce tree vigour.
The combined use of these two bioregulators would be dependent upon orchard vigour and shoot growth evolution.

X International Symposium on Plant Bioregulators in Fruit Production

L. Asin, P. Vilardell

paclobutrazol, prohexadione-calcium, shoot growth, pear

https://doi.org/10.17660/ActaHortic.2006.727.14