The effect of growth regulators on sex expression in melon (Cucumis melo L.)

• Published in: Crop breeding and applied biotechnology 2013-10, Vol.13 (3), p.165-171
• Main Authors: Girek, Zdenka, Prodanovic, Slaven, Zdravkovic, Jasmina, Zivanovic, Tomislav, Ugrinovic, Milan, Zdravkovic, Milan
• Format: Article
• Language: English
• Subjects: AGRONOMY; Andromonoecious; BIOTECHNOLOGY & APPLIED MICROBIOLOGY; ethrel; flower; gibberellic acid; Growth regulators; monoecious; Regulators
• ISSN: 1984-7033; 1518-7853; 1984-7033
• DOI: 10.1590/S1984-70332013000300003

Seven traits related to flowering and sex expression in melon were studied and their reaction to application of two growth regulators (ethrel and gibberellic acid) was observed. Four monoecious genotypes (Sesame, ED-3, ED-4, Pobeditel) and four andromonoecious genotypes (Chinese muskmelon, Anannas, Fiata, A2-3lb) had been used for experiments. According to the results, ethrel had higher effects on the investigated traits than gibberellic acid. Ethrel increased the number of perfect flowers per plant for 7.18 (31.42%), reduced the number of male flowers per plant for 21.47 (17.98%), affected earlier appearance of the first pistillate/perfect flower for 3.68 days, and delayed the appearance of the first staminate flower for 16.07 days. Changes in the last two traits caused an extension of the period from the emergence of the first pistillate/perfect to the first staminate flower from 0.1 to 21.57 days, which represents the strongest effect of ethrel. Gibberellic acid had generally opposite effects on the studied traits. Foram selecionadas sete características relacionadas ao florescimento e expressão do sexo no melão e, em seguida, observada a reação de dois reguladores de crescimento (Ethrel e ácido giberélico). Quatro genótipos de flores monóicas (Gergelim, ED-3, ED-4, Pobeditel) e quatro genótipos andromonóicos (Melão chinês, Anannas, Fiata, A2-3lb) foram ensaiados durante dois anos. Ethrel teve um efeito mais forte do que o ácido giberélico, aumentando o número de flores femininas/hermafrofitas por planta para 7,18 (40,61%) e reduzindo o número de flores masculinas para 21,47 (17,98%). Ethrel adiantou o aparecimento da primeira flor feminina/hermafrofita em 3,68 dias, e atrasou o aparecimento da primeira flor masculina em 16.07 dias. Como consequência, percebe-se que Ethrel prolonga o período entre o aparecimento da primeira flor fêmea/hermafrodita até a primeira flor masculina de 0,1 dia para 21,57 dias, sendo este o efeito mais forte (99,49%).