Effect of spray combinations of IAA, GA3 and zeatin on berry growth and quality in 'Superior Seedless'
Table grapes must reach standards for marketing, with the equatorial diameter of berries a major quality variable required for 'Superior Seedless'. Growth regulators, gibberellic acid (GA3), are currently used to increase the diameter of berries. However, there is no local information about effects of other growth regulators on berry size. The purpose of this research was to assess the effects of IAA, GA3 and zeatin on quality variables in 'Superior Seedless' in San Juan, Argentina. Treatments were: control, TI, GA3 (20 ppm); TII, IAA (1.5 ppm); TIII, IAA (1.5 ppm plus 1.5 ppm, a week later); TIV, IAA (1.5 ppm) with GA3 (20 ppm); TV, application of a commercial mix containing IAA (2.5 ppm), GA3 (2.5 ppm) and zeatins (8.2 ppm) and TVI, GA3 (20 ppm) plus the commercial mix, applied to berries when they had 8-10 mm of equatorial diameter. Treatment TIV generated the highest growth rate of berries. A synergy effect was observed among regulators in view of the high values obtained in equatorial diameter, weight of berries and bunches after TVI and TIV. The latter showed lower concentrations of soluble solids and higher shattering. TVI gave the best length/equatorial diameter of berries and the lowest percentage of rachis dehydration. TI and TV resulted in higher firmness of berries. Moreover, no significant differences were observed for the variables percentage of stained, watery or rotten berries. To conclude, treatment with IAA, GA3 and zeatins improved the quality variables in 'Superior Seedless'.
Mulet Jalil , M.A., Molinelli Maratta , J.P. and Pugliese, M.B. (2017). Effect of spray combinations of IAA, GA3 and zeatin on berry growth and quality in 'Superior Seedless'. Acta Hortic. 1157, 125-130
auxin (IAA), gibberellic acid (GA3), cytokinins (zeatins), 'Superior Seedless', berry size