Comparison among 18 hexyl esters of 1-naphthylacetic acid used on grapevine

Eighteen esters derived from 1-naphthylacetic acid (NAA) and from hexyl iso mer alcohols were synthesized and sprayed on grapevine suckers at 1, 2, 4, and 8% w/w concentrations to test their sucker control efficiency 2, 10, an d 30 days and 1 year after their application. All compounds gave a prompt c ontrol of suckers. After 1 year, sucker growth was inhibited by the derivat ives from primary and secondary alcohols, whereas the number of suckers was reduced only by application of naphthyl acetates of tertiary alcohols.