Beneficial Effect of Ethephon on Yield and Sucrose Productivity of Sugarcane Cultivars in Thailand

Abstract

Experiments were conducted to determine the effect of the growth regulator “Ethephon” on germination and initial growth of four sugarcane cultivars (pot trial) and yield and sugar content of five sugarcane cultivars (field trial). The pot trial was replicated five times, with each replicated treatment containing 12 three-budded setts. The field trial was conducted using five Thai commercial cultivars with each planted in six rows x 5 m long, replicated thrice. Three concentrations of Ethephon ( 100, 250, and 400 mg/L) were used. Ethephon was sprayed when the plant cane was five months old. A plant and two ratoon crops were evaluated for the effect of treatment on yield and sugar content. Improved germination of treated plants was observed following treatment with 100 mg Ethephon/L resulting in increased germination in all cultivars (pot trial). Treatment resulted in increased lengths of shoots and roots. Increased fresh and dry weight in the treated setts also was observed. Differential response of the cultivars to the treatments was observed. Ethephon at 400 mg/L significantly increased yield in all cultivars except K 87-17 (plant cane) with a maximum of 83.06 t/ha in K 88–92. Positive response of sucrose accumulation to Ethephon in plant cane was seen with maximum effect at 400 ppm. Maximum increase of 2.5 units CCS was observed in variety K 84-69. Overall, on ratoon crops, Ethephon at 100 mg/L increased total sugar yield (K 86–161 recorded 10.13 t/ha in first ratoon and K 88–92 recorded 10.88 t/ha in second ratoon). Based on the present study, we found spraying Ethephon was beneficial in increasing CCS, cane, and sugar yield of sugarcane cultivars with 100 mg Ethephon/L producing the best effect.