REFINING AVIGLYCINE TREATMENTS TO IMPROVE CONTROL OF NATURAL INDUCTION OF 'MD-2' PINEAPPLE
Natural induction of inflorescence development (NI) of pineapple is a serious problem in pineapple fields in many areas where sensitive pineapple cultivars are grown in subtropical environments. In Hawaii, NI begins in late November and continues through February. Experiments to test the efficacy of AVG (aviglycine hydrochloride, AVG HCL) in controlling NI were installed in irrigated fields of MD-2 pineapple on Oahu, Hawaii at elevations of 145 m (2008-09) and 275 m (2009-2010). There were 67,925 plants ha-1 and plant weights when first treated were about 2.0 kg in 2008-2009 and 1.9 kg in 2009-2010. Plots were sprayed with ReTain® (15% AVG soluble powder), at the equivalent of 2337 L ha-1. NI in control plots exceeded 40% in both years. Weekly sprays of 100 mg L-1 AVG significantly reduced NI to about 1.0% in 2008-2009 and to about 15% in 2009-2010. Plots sprayed biweekly with 100 mg L-1 AVG had significantly less NI than the control but significantly more than plots sprayed weekly. When the first four and last six of 17 weekly sprays were at concentrations of 50 or 75 mg L-1, control of NI was comparable to results obtained with 17 weekly sprays at 100 mg L-1. Sprays of AVG had no significant effect on average fruit weight. When sprays were begun after NI had occurred, serious fruit deformity resulted in the loss of almost all such fruit. Sprays of AVG to control NI must begin before NI begins or losses could exceed those associated with NI in untreated fields.
Bartholomew, D.P., Uruu, G., Lopez, J.A. and Leep, D. (2011). REFINING AVIGLYCINE TREATMENTS TO IMPROVE CONTROL OF NATURAL INDUCTION OF 'MD-2' PINEAPPLE. Acta Hortic. 902, 211-219
aviglycine hydrochloride, flower induction, deformed fruit, average fruit weight