Use of Ethephon and Monopotassiumphosphate Combined with Potassium Chlorate to Induce Off-season Flowering of Longan cv. Daw in Rainy Season

Abstract

Study on using ethephon and monopotassiumphosphate combined with potassium chlorate to induce off-season flowering of longan cv. Daw in rainy season was carried out during 12 May 2010 to 15 December 2010. The experiment was designed base on completely randomized design (CRD) with 4 treatments and 5 replications as followed; 1) control (no potassium chlorate and no foliar spray with fertilizer) 2) soil drench with potassium chlorate at 15 g /m² of canopy diameter  3) foliar spray with fertilizer 0-52-34 1% and ethephon 400 mg/L and 4) soil drench with potassium chlorate at 15 g /m² combined with foliar spray with fertilizer 0-52-34 1% and ethephon 400 mg/L. The result revealed that longan plants treated with potassium chlorate at 15 g /m² as soil drench combined with 1% of 0-52-34 and ethephon 400 mg/L was induced off-season flowering in rainy season and flowered ealier 7 days than only potassium chlorate treatment up to 7 days. Moreover, this treatment gave the highest percentage of flowering (86%), flower panicle type (100%), perfect flower (15%) and fruit setting (92%), while as only potassium chlorate treatment had the percentage of flowering (66%), flower panicle type (46%) and fruit setting (52%). However, the control treatment and only foliar spray with 1% of 0-52-34 and ethephon 400 mg/L treatment were not produced flower at all.