Identifying agrichemical alternatives to hydrogen cyanamide in 'Zesy002' ('Gold3') kiwifruit

G. Hernández, R.L. Craig
Zespri International Limited has supported the research of alternative bud break enhancers to hydrogen cyanamide (HC), given the potential for this chemical to be de-registered for use in the kiwifruit industry and the serious risks of production loss from current kiwifruit cultivars should this occur. Erger® (ER) was tested as an alternative commercial bud break enhancer in field conditions using equipment that mimicked commercial air blast spraying technology, with a tractor mounted boom sprayer and Air Inclusion (AI) nozzles purpose designed to apply 800 L of water ha-1. ER and HC were applied at three timings 6-8 days apart ranging from 53 to 31 days before natural bud break. The year 2013 had low winter chill with 279 h below 7°C compared to the 19 year mean of 388 h. The optimal timing tested for HC application to 'Gold3' was 38 days before natural bud break, which is consistent with a cane painting study conducted in the same season, where the optimum was 31-45 days before natural bud break. ER induced flower production was 62.4% above the control but 24.4% below HC in terms of king flowers winter bud-1. The successful use of bud break enhancers has proved to be important for the commercial production of 'Gold3'.
Hernández, G. and Craig, R.L. (2016). Identifying agrichemical alternatives to hydrogen cyanamide in 'Zesy002' ('Gold3') kiwifruit. Acta Hortic. 1130, 123-130
DOI: 10.17660/ActaHortic.2016.1130.18
Actinidia, budbreak, flowering, Hi-Cane®, Dormex®, Erger®, boom sprayer

Acta Horticulturae