Thinning is one of the major cultural practices influencing yield and fruit quality in pome fruit production. While there are recommendations available for chemical thinning of many apple cultivars, there is little information available on chemical thinning programs for pears.
In this research, Dr Sally Bound from TIA conducted trials at Nubeena in Tasmania over a two year period to develop chemical thinning programs for the European pear cultivar 'Packham's Triumph' and to assess the impact of thinning chemicals on fruit quality.
The results will give growers increased options when determining their thinning programs.
The study demonstrated that the post-bloom thinner BA is a consistent thinner of 'Packham's Triumph' providing weather conditions are suitable, and it can be applied as early as 10 dAFB to as late as 40 dAFB, several days later than previously reported. While BA can be used as a standalone thinner of 'Packham's Triumph', it is risky to rely on one spray application in case weather conditions are unsuitable for application. Two applications of BA did not increase the thinning effect.
The blossom thinner ATS proved to be an effective thinner, and two applications during the flowering period would be recommended. It can also be effectively combined in a program with the post-bloom thinner BA.
Citation: Bound, SA, Optimising crop load and fruit quality of 'Packham's Triumph' pear with ammonium thiosulfate, ethephon and 6-benzyladenine, Scientia Horticulturae, 192 pp. 187-196. ISSN 0304-4238 (2015) [Refereed Article]
View the full paper (PDF)
Published on: 17 Dec 2015 10:18am