Effect of Ethrel and Gibberelic Acid on Growth, Flowering, Sex Ratio and Yield to Luffa Plant

The present field experiment was consummated throughout two successive seasons (2016/2017 and 2017/2018) at the nursery of Horticulture Research Institute, Agriculture Research Center, Giza, Egypt on Luffa cylindrical. The aim to study the effect of some growth regulators (ethrel and gibberellic acid) at different levels on growth, flowering and sex ratio of Luffa cylindrical on February 28 in both seasons at 4 m distance between plants. After planting, the plants were treated with the first spray after two leaves grown, and the second spray was received after 4 leaves grown, then after that the plants were treated with spraying every 21 days until June 16. The experiment was incorporated in randomized complete design with three replications and nine treatments viz 4 concentrations each of ethrel (50, 100, 150 and 200 ppm) and GA3 (100, 150, 200 and 250 ppm) and control i.e. tap water spray were investigated. The results emphasized that, ethrel treatments especially at 100 ppm showed beneficial effect on improving most plant traits in both seasons (stem length, stem diameter, No. of leaves/plant, No. of branches/plant, fruit length, fruit circumference and its yield). Meanwhile, GA3 gave was less effect on plant quality and in some instances caused a decrement on some plant parameters. The obtained results exert also the great effect of treating plants with ethrel at 100 ppm for raising number of female flowers/plant, besides raising sex ratio. Also, the growth regulators used (ethrel and GA3) caused an improvement in chemical constituents of the newly formed plants (N, P and K and chlorophyll a, b and carotenoids in both seasons). On the other hand, an economic feasibility study was made that was inferred through the economic evaluation of some economic indicators (total revenue per feddan, gross profit margin, ratio of total revenue to costs), which was calculated to evaluate the ethrel treatment at a concentration of 100 ppm and found it was achieved positive results at the level of the indicators mentioned and also it was found that it achieved high productivity per acre compared to control and other transactions. From the results, it could be recommended to foliar spraying plants with ethrel at the level of 100 ppm as such treatment proved its mastery in most cases on plant traits.