This could occur because of the wounding-induced ethylene (Kato et al.,2000). The earlier fragrance of Kradang Nga Chin flower was also perceptibly observed after treated with ethephon (ethylene releasing agent) in the current experiment. Our results revealed that 1000 ppm ethephon was capable to initiate the detached mature green (light green) Kradang Nga Chin flower for earlier scenting from 3 PM (Table1). This enhancement was obviously found in greenish yellow stage of detached Kradang Nga Chin flower which emitted the fragrant volatiles from 3 PM in 200 ppm ethephon treatment and earliest from 2 PM by applying 1000 ppm ethephon (Table1). The treated petal of greenish yellow stage released strong smell in cooperation with blooming in advance. Besides, high concentration of ethephon induced enormously open of flower petal (Figure 1) that similar to the response of ethylene in leaf epinasty (Ursin and Bradford, 1989). Nevertheless, this acceleration was ineffective for early-mature (dark green) stage and 1-MCP could exterminate the effect of ethephon (Table 1). Thus, the stage of floral development in Kradang Nga Chin showed different response to various ethylene concentrations. This phenomenon resembles the ripening behavior of climacteric fruit which ethylene can trigger the ripening process in mature green fruit. Therefore, from our results, we can conclude that the blooming and scenting of Kradang Nga Chin flower was similar to those ripening of climacteric fruit.