EFFECT OF POTASSIUM CHLORATE ON FLOWERING, TOTAL NITROGEN, TOTAL NONSTRUCTURAL CARBOHYDRATE, C/N RATIO, AND CONTENTS OF CYTOKININ-LIKE AND GIBBERELLIN-LIKE SUBSTANCES IN STEM APEX OF ‘DO’ LONGAN

The effect of potassium chlorate (KClO₃) on flowering, total nitrogen (TN), total nonstructural carbohydrate (TNC), carbohydrate/nitrogen (C/N) ratio, and contents of cytokinin-like and gibberellin-like substances in stem apices of ‘Do’ longan were studied in CRD, with four treatments of KClO₃ at 0, 200, 500, and 800 g/tree by soil application.
There were three replications with one tree/replication.
The results revealed that all KClO₃-treated trees were flowering before the untreated trees.
TN of all KClO₃-treated trees tended to be higher than untreated ones.
TNC of all KClO₃-treated trees tended to decrease before flowering (1^st-3^rd week) then increase after flowering, while the untreated trees tended to decrease gradually.
During flowering period (2^nd-5^th week), C/N ratios of all KClO₃ treated and untreated trees were not significant different (P = 0.05). The contents of cytokinin-like and gibberellin-like substances were determined by soybean hypocotyl and rice secondary-leaf-sheath bioassays.
The results revealed that the stem apices from all potassium-chlorate treatments had higher contents of cytokinin-like substance and lower gibberellin-like substance than the untreated trees.

II International Symposium on Lychee, Longan, Rambutan and other Sapindaceae Plants

N. Wangsin, T. Pankasemsuk

soybean-hypocotyl bioassay, rice secondary-leaf-sheath bioassay, flowering process, leaf flushing, nutrients, hormonal balance

https://doi.org/10.17660/ActaHortic.2005.665.29