The modification of the sex expression in melon (Cucumis melo L.) by the ethrel treatment

Abstract

In this study, eight melon genotypes belonging to two groups of cultivars according to flowering type (monoecious and andromonoecious) were treated with the plant growth regulator ethrel with the aim to induce the modification of their sex expression. Experiments with treated and control plants were set up in the fields of the Institute for Vegetable Crops at Smederevska Palanka, Serbia, during two years (2010 and 2011). Effects of ethrel were observed on three traits in individual plants: 1) total number of flowers, 2) the percentage of pistillate and perfect flowers and 3) the percentage of staminate flowers per plant. Results showed that exogenous application of ethrel affected decreasing of the total number of flowers, as well as, the change in frequency of flower types within individual melon plants. Ethrel stimulated the formation of pistillate and perfect flowers followed by the deformation of anthers within the perfect flowers. Additionally, ethrel affected decreasing of percentage of staminate flowers in all eight studied melon genotypes. These results are important for the improvement of the F1 melon hybrid seed production in Serbia. It was found that simple spraying of young melon plants with ethrel, eliminated the need for emasculation of flowers in mother plants in crosses.

U ovom radu, osam genotipova dinje koje pripadaju dvema grupama sorti prema tipu cvetanja (monoecijskim i andromonoecijskim) je tretirano etrelom u cilju indukovanja modifikacija u ekspresiji pola. Ogledi sa tretiranim i kontrolnim biljkama postavljeni su na poljima Instituta za povrtarstvo u Smederevskoj Palanci, Srbija, tokom dve godine (2010. i 2011). Efekat etrela posmatran je na tri svojstva individualnih biljaka: 1) ukupan broj cvetova, 2) procenat ženskih i hermafroditnih cvetova i 3) procenat muških cvetova. Rezultati su pokazali da primena etrela izaziva smanjenje ukupnog broja cvetova, kao i promene u zastupljenosti tipova cvetova kod individualnih biljaka dinje. Etrel je stimulisao formiranje ženskih i hermafroditnih cvetova, uz deformisanje antera unutar hermafroditnih cvetova. Takođe, etrel je uticao na smanjenje učešća muških cvetova kod svih osam proučavanih genotipova dinje. Ovi rezultati značajni su za unapređenje proizvodnje semena F1 hibrida dinje u Srbiji. Utvrđeno je da obično prskanje mladih biljčica dinje etrelom, eliminiše potrebu za emaskulacijom cvetova majčinskih biljaka u ukrštanjima.