Analyzing the effects of different GA3 applications on plant root architecture and above-ground properties in tulip cultivars

In the study, the effects of 0, 100, 200 and 400 ppm spray applications of GA3 on root and above-ground parts of 'Jan Reus', 'Bloody Mary' and 'Yokohama' tulip cultivars were determined. According to the results, on the development of plant upper part properties, 200 ppm in 'Jan Reus' and 'Yokohama' and 100 ppm in 'Bloody Mary' were the most effective applications. Again, the least increases in upper part properties were obtained from the control plants in 'Jan Reus' and 'Bloody Mary', and from the 100 ppm application in 'Yokohama'. While 100 ppm was the most effective application in 'Jan Reus' and 'Yokohama' in terms of root development, the effect of the applications in 'Bloody Mary' was lower than the control. The application that least increased root development was determined as 400 ppm in 'Jan Reus' and 200 ppm in 'Bloody Mary' and 'Yokohama'. Root growth was found to be negatively related to GA3 content. High GA3 is thought to negatively affect overall root growth, possibly by suppressing the effect of auxin. It is assumed that GA3 produced by the plant itself may be sufficient for root development or may be effective at much lower dose applications. On the other hand, it has been determined that the effects of GA3 application vary depending on the variety. According to these results, it is recommended to apply it at a dose of 200 ppm to ensure flowering by providing cooling in tulip cultivars and cut flower cultivation. High doses of GA3 are not recommended for root development.