Applying Calcium Carbide Solution Affect Sex Expression and Increases Yield of Monoicous Cucumber

Sex expression in cucumber is influenced by hormonal and environmental factors such as day length and temperature. Increasing female flowers that will develop to fruit is a trick for increasing yield, hence it’s importance. Likewise, it would help breeders through hybridizing process. Ethylene as a plant hormone is known to increase female flowers of most members of Cucurbitaceae family but as an exception increase in watermelon’s female flowers reported under the effect of gibberlic acid. Ethylene is a gaseous ubiquitous phyto-hormone that is known to influence sex expression in cucumber. As acetylene’s chemical structure with a minor difference is almost similar to gaseous hormone ethylene, in higher concentrations it is expected to retain the same physiological effects as ethylene. This experiment evaluated the effect of foliar application of different concentration of liquid solution of acetylene (0, 50, 250, 500, 750 and 1000 ppm) released from calcium carbide on cucumber sex expression and other physiological traits of cucumber. Results showed that number of female flowers and some vegetative traits of cucumber affected by different concentration of acetylene solution. Maximum number of female flowers obtained by applying 500 ppm of acetylene solution. The maximum leaf area and chlorophyll content of fruit achieved by application of 250 ppm and the maximum number of internodes obtained by 500 ppm acetylene solution. In conclusion, using acetylene as the solution form has not been reported until now. Foliar spraying of acetylene increased the female flowers in cucumber. The highest yield linked with 250 ppm of acetylene solution.