THE USE OF RAPESEED OIL TO REDUCE PREMATURE DEFOLIATION IN SWEET CHERRY SPRAYED WITH BORDEAUX MIXTURE FOR CONTROL OF BACTERIAL CANKER

Abstract

Premature defoliation in sweet cherry trees sprayed with Bordeaux mixture for bacterial canker control was reduced by amending sprays with rapeseed oil. The time of 50% leaf drop was delayed with amended sprays by 10–14 days on the cultivars Venus, Vista, and Hedelfingen. Vegetable oils similar to rapeseed oil are recommended for use with Bordeaux mixture to prevent possible long-term effects on growth and winter injury resistance due to premature defoliation.