Understanding and overcoming seed dormancy in eggplant (Solanum melongena L.) breeding lines

Abstract

The seed dormancy of six eggplant (Solanum melongena L.) genotypes were studied. Two genotypes (33 and 34) were breeding lines while the other four (1-00261, 2-02619, 7-00568, 12–00823) belonged to the exotic germplasm of the Institute for Vegetable Crops in Smederevska Palanka. In order to break the dormancy, the seed was treated with: (1) low temperature, at 4 0C for 96 hours (4 days), 72 hours (3 days) and 48 hours (2 days), continually; (2) hormones, gibberellic acid (GA3) in three concentrations: 5 ml/100 ml, 15 ml/100 ml, and 25 ml/100 ml for 24 hours and after that seeds were allowed to germinate; (3) chemicals, with potassium nitrate KNO3 solution at concentrations 0.5, 1 and 1.5% for 24 hours. Non-treated seed was the control. The trial was set according to two-factorial ANOVA, with four repetitions. The AMMI model was applied for analyzing the interaction of genotypes and treatments for increasing seed germination (break of dormancy). Genotype 12 reacted most favorably to treatments KNO3 1%, KNO3 1.5%, GA3 15 mg/100 ml and GA3 25mg/100 ml. Three genotypes (33, 7 and 12) represent the least stable genotypes, since they reacted positively to all treatments, and most intensively to treatment with GA3 25 ml/100 ml. The low temperature treatment increased germination but not in the expected range, since the highest impact had the low temperature regime for 48 hours.