Effects of Spermidine and Putrescine Applications on Haploid Plant Obtention Via Ovule Culture in Sak？z and Dark Green Squashes (Cucurbita pepo L.)

In this study, the effects of spermidine and putrescine on the haploid plant obtention via ovule culture were investigated in Sak？z and dark green squashes. As plant material, 3 different cultivars of Sak？z and 3 different cultivars of dark green squashes were used. 5 mg L-1 2.4-D added MS medium was used for embryo stimulation in ovule culture applications. To determine the effects of polyamines, spermidine (Spd) and putrescine (Put) were used with the concentrations of 40, 80 and 160 μM L-1. Furthermore, spermidine and putrescine were used together with concentration of 80, 160 and 320 μM L-1 (1:1, v/v), respectively. The control group included only 5 mg L-1 2.4-D. According to the results of the research, it was determined that ovule development and callus formations were at different levels for each cultivar. When the ovule development results were examined, it is found that the ovule development rates obtained in all cultivars were generally more successful than the control group. According to the result of callus formation; the best culture medias were only Put and Spd for Elida F？ cultivar, Put+Spd-containing media for Roni F？ cultivar, Spd and Put+Spd-containing medias for Shakila F？, Put and Put+Spd-containing medias for Briallante F？, and only Put in Chivas F？. Generally, the best callus growth rate was found in 40 μM L-1 Put containing media, but plant was not obtained from these callus. In order to obtain haploid plants, it is recommended to use polyamines in higher doses