Effects of plant growth regulators on growth, yield characteri̇stics and essential oil biosynthesis of dill (Anethum graveolens l.)

In this research it is aimed to determine the effects of Gibberellic asit (GA3), Metil Jasmonat (MJ), Kinetin and Indol asetik asit (IAA) on some plant characters, fruit yield and essential oil content and composition of dill. The research were conducted at 2018 in ISUBU Tarımsal Araştırma ve Uygulama Merkezi fields at 3 replicates. Different consantrations of plant growth regulators ie; GA3 (100, 200 ppm), MJ (0.25, 0.5 mM), Kinetin (25, 50 ppm) and IAA (100, 200 ppm) were pulverized to dill plants at the beginning of flowering stage. In this study, vegetation period, plant height, main branch number, umbel number per plant, fruity umbel number, main umbel diameter, rays number, fruit number per umbel, thousand fruit weight, fruit yield, essential oil content and composition were examined. Plant growt regulators had a statistically significant effect on all examined parameters in the research. Main branch number and umbel number significantly increased with MJ and IAA applications. MJ and kinetin applications were significantly increased to main umbel diameter, rays number, fruit number and fruit yield of main umbel compared to control. The highest fruit yield were obtained from 0.50 mM MJ applications wich increse the yield by 30% over the control. 200 ppm IAA applications decreased the fruit yield by 21% compared to control. Essential oil content increased with the applications of 100 ppm GA3 and 0.25 mM MJ while 50 ppm kinetin and 200 ppm IAA caused to decrease of essential oil content. While the components of the essential oil were similar in all applications, the proportions of the components showed significant variation depending on the PGR applications. Growth regulators increased the content of limonene, while reduced the carvone content in the essential oil. In this study, it was concluded that fruit yield and essential oil production of dill can be increased especially with MJ applications.