The effect of temperature pre-treatment, light and plant growth regulators on callus induction in pumpkin (Cucurbita pepo var. Styriaca) anther culture

This study was performed to investigate the effect of various factors on callus induction and haploid embryo production in the anther culture of Pumpkin (Cucurbita pepo var. Styriaca). For experiments, pumpkin seeds were planted in the greenhouse and at the time of flowering, male flower buds with a size of 1.5 cm were selected and sterilized for use in later stages. The experiments were performed as a factorial experiment in a completely randomized design with 3 replications. The first experiment studied the effect of cold pretreatment on three levels of bud cold pretreatment, anther cold pretreatment and without cold pretreatment (control) and the combination of plant growth regulators on callus formation in anther culture. Cold pretreatment of buds and culture of anthers in culture medium containing 1 mgl-1 NAA and 2 mgl-1 2,4-D produced the highest callus formation percentage. In the second experiment, the effect of heat pretreatment on the percentage of callus formation was investigated. In this experiment, the best response was related to 32°C treatment for 7 days. The third experiment consisted of the interaction effectt of light treatments and growth regulators on callus formation in anther culture of Pumpkin. Anthers that cultured in light conditions with a hormonal concentration of 2.5 mgl-1 2,4-D + 1 mg /l BAP showing the highest percentage of callus formation. In the fourth experiment, androgenesis was applied by culturing microspores in E20 medium, which led to the growth of a number of microspores, and in the cytological examination, the symmetric divisions were observed.