Effect of AVG application on fruit set, yield and fruit size in ‘Abate Fetel’ and ‘Packam’s Triumph’ pears in a semi-commercial statistical trial

Abstract

Fruit set in pear (Pyrus communis L.) can be low and unpredictable. The aim of this study was to increase fruit set and subsequently yield in ‘Abate Fetel’ (AF) and ‘Packham’s Triumph’ (PT) pears. The influence of aminoethoxyvinylglycine (AVG) application was investigated in a semi-commercial statistical trial in Río Negro, Argentina in the 2009-2010 season. The applications were randomly performed on eight rows at two stages of growth (full bloom and 14 days after full bloom) and two rates (125 and 250 mg L-1) with an untreated control. Application volume was set at 500 L ha-1 in order to make the application economically affordable for growers. Fruit drop, fruit set 60 DAFB, number of fruit per cm2 branch cross sectional area, fruit size (weight, width, height), number of seeds per fruit and yield were evaluated. AVG 250 mg L-1 treatment at full bloom reduced yield in both cultivars (12% in PT and 8% in AF). However, treatments at 14 days after full bloom improved fruit set in both cultivars, but only the higher rate was effective in PT. In this cultivar, a 22% increase in fruit set and a 33% increase in yield were recorded with AVG application at 250 mg L-1. In AF, AVG 14 days after full bloom reduced fruit drop at 30 DAFB, improved fruit set (65%) and yield (16%), especially during the first harvest. We conclude that AVG at 250 mg L-1 applied two weeks after full bloom can increase fruit set and yield in the cultivars PT and AF.