Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2006
Publication Date: 9/20/2007
Citation: T.K. Matsumoto, M.A. Nagao and B. Mackey. 2007. Off-season flower induction of longan with potassium chlorate, sodium chlorite and sodium hypochlorite. HortTechnology 17(3): 296-300. Interpretive Summary: Off-season flowering and fruiting of longan is readily achieved by application of potassium chlorate, a common ingredient in fireworks, to the soil or foliage of longan trees. However, the explosive nature of chlorate makes it difficult to purchase, transport, and store. Here we show that hypochlorite, the active ingredient in household bleach, is able to induce off-season flowering and fruiting of longan similar to chlorate treated trees. Chlorate in the bleach solution is likely to contribute to the off-season flowering of bleach treated trees.
Technical Abstract: Flower induction of longan with potassium chlorate has improved availability of longan fruit, but potassium chlorate is potentially explosive and often difficult to purchase, transport, and store. Previous reports suggested that hypochlorite enchances natural flower induction. This study is the first to demonstrate that chlorite and hypochlorite (bleach) induced off-season longan flowering similar to chlorate treated trees. Hypochlorite induction of flowering with bleach was likely due to chlorate in the bleach solution. Chlorate was present in the leachate from potted longan trees treated with bleach and was detected in bleach prior to soil application. The quantity of chlorate found in bleach induced flowering to the same or greater extent as equivalent quantities of potassium chlorate, suggesting chlorate is an active ingredient responsible for longan flowering.