Benzyladenine and other Benzyladenine and other Chemicals for Thinning Chemicals for Thinning ‘Empire’ Apple Trees‘Empire’ Apple Trees

Diego Revilla PascualBasilio Berisa PradoManuel Palacios CallejaAndrtes Bozal Andres

Index Index

The objectThe object

Methodology of the experimentMethodology of the experiment

ResultsResults

ConclusionConclusion

The objectThe object

BenzyladenineBenzyladenine

Benzyladenine + gibberellins Benzyladenine + gibberellins

Naphthaleneacetic Naphthaleneacetic Acid(NAA) Acid(NAA)

Carbaryl (CB) Carbaryl (CB)

Vs

MethodologyMethodology

Experiment 1: Compared BA Experiment 1: Compared BA vs NAA. vs NAA. – 1) Control (no treatment).1) Control (no treatment).– 2) BA at 50, 100, or 150 mg 2) BA at 50, 100, or 150 mg

active ingredient (a.i.)/liter. active ingredient (a.i.)/liter. – 3) NAA at 5, 10, or 15 mg 3) NAA at 5, 10, or 15 mg

a.i./litera.i./liter

MethodologyMethodology

Experiment 2: Compared BA Experiment 2: Compared BA and NAAand NAA – 1) BA at 0, 50, 100, or 150 mg 1) BA at 0, 50, 100, or 150 mg

a.i./liter;a.i./liter;– 2) NAA at 0, 5, or 10 mg 2) NAA at 0, 5, or 10 mg

a.i./liter. a.i./liter. – The control (BA 0 + NAA 0) was The control (BA 0 + NAA 0) was

untreateduntreated

MethodologyMethodology

Experiment 3: Compared BA, Experiment 3: Compared BA, NAA, and CB. NAA, and CB. – 1) Control (no treatment).1) Control (no treatment).– 2) BA at 50 or 100 mg a.i./liter.2) BA at 50 or 100 mg a.i./liter.– 3) NAA at 5 or 10 mg a.i./liter.3) NAA at 5 or 10 mg a.i./liter.– 4) CB at 500 or 1000 mg 4) CB at 500 or 1000 mg

a.i./litera.i./liter

MethodologyMethodology

Experiment 4: Compared BA and Experiment 4: Compared BA and PR vs. application timing. PR vs. application timing. – 1) BA 75 or 150 mg a.i./liter.1) BA 75 or 150 mg a.i./liter.– 2) PR 75 or 150 mg a.i./liter. 2) PR 75 or 150 mg a.i./liter. – BA and PR treatments were applied BA and PR treatments were applied

of on 15 May (6 Days after flower of on 15 May (6 Days after flower bloom, mean fruit diameter 3.6 ± 0.9 bloom, mean fruit diameter 3.6 ± 0.9 mm), 29 May (20 DAFB, mean fruit mm), 29 May (20 DAFB, mean fruit diameter 10.2 ± 2.4 mm), or 7 June diameter 10.2 ± 2.4 mm), or 7 June (29 DAFB, mean fruit diameter 17.1 (29 DAFB, mean fruit diameter 17.1 ± 3.9 mm)± 3.9 mm)

ResultsResults

BA consistently reduced ‘Empire’ fruit set BA consistently reduced ‘Empire’ fruit set and increased fruit weight to the same or and increased fruit weight to the same or a greater extent than NAA or CBa greater extent than NAA or CB

Effects of BA and NAA were not influenced Effects of BA and NAA were not influenced when they were applied of together in a when they were applied of together in a tank mixtank mix

BA reduced yield in the three of four trialsBA reduced yield in the three of four trials BA treatment suggest significant BA treatment suggest significant

improvement in the fruit-size distribution improvement in the fruit-size distribution in the cropin the crop

ResultsResults

BA applied of as a thinner stimulated BA applied of as a thinner stimulated increased shoot growth in three of the four increased shoot growth in three of the four trialstrials

BA applications at or shortly after bloom BA applications at or shortly after bloom have been shown to stimulate lateral buds have been shown to stimulate lateral buds to form shoots. to form shoots.

PR:PR:– Was not as effective as BA for thinning Was not as effective as BA for thinning – Reduced the number of seeds per fruit in two Reduced the number of seeds per fruit in two

of the three application of the three application

ConclusionConclusion

BA displayed the reliability in BA displayed the reliability in thinning associated with CBthinning associated with CB

BA thinner responses were BA thinner responses were concentration-dependent concentration-dependent

BA has considerable promise as a BA has considerable promise as a thinner for mature “Empire” apples thinner for mature “Empire” apples treestrees