Effect of biochar application on the development of some edible flowers and melatonin application on storage performance

ABSTRACT THE EFFECT OF USE BİOCHAR AMENDMENT ON THE DEVELOPMENT OF SOME EDİBLE FLOWERS AND THE EFFECT OF MELATONİN ON THEİR STORAGE PERFORMANCES. Yılmaz Vural, Güzella PhD Thesis, Horticulture Department Supervısor: Prof. Dr. Kenan Yıldız March 2024, x 101 Pages (*) This study was carried out by Tokat Gaziosmanpaşa University Scientific Research Projects (Project number: 2021/99). In the study, it was aimed to determine the effects of biochar application on plant development and phytochemical properties of edible flowers, which are increasingly included in gastronomy and whose commercial value is increasing day by day, as well as the effects of melatonin application on the quality losses that occur during the storage processes of these flowers. Red Nasturtium (Tropaeolum majus L.), Yellow Nasturtium (Tropaeolum majus L.), Calendula (Calendula officinalis L.) and Electric Flower (Spilanthes oleracea) were used in the study. Plants were produced from seeds, and seed emergence rates were also determined within the scope of the study. It has been determined that the highest seed emergence rate among edible flowers is in calendula seeds, and the lowest emergence rate is in electric flower seeds. Plants propagated by seeds were transplanted into pots containing soil, peat or biochar-added soil. As a result of the measurements made to determine plant development, it was determined that plants in pots containing peat or biochar showed better development compared to plants grown in pots containing only soil. Biochar application significantly increased the number of flowers per plant and therefore the yield in all four edible flowers used in the study. While the phenol content and antioxidant capacity of flowers differed depending on the plant species, the effect of growing mediums was found to be insignificant in all flowers. When the vitamin C content of edible flowers was examined, it was seen that nasturtiums had higher vitamin C compared to the other two edible flowers in all three growing mediums. The obtained flowers were stored after being immersed in 0 and 100 mM melatonin solution, and the effects of melatonin applications on the storage life were evaluated. Significant increases in total phenol, vitamin C, SSC and antioxidant contents in all flowers was determined as the storage time progress. It was observed that melatonin applications did not make any difference on the phytochemical properties and color parameters of the plants compared to the control group. According to the results of the sensory analysis, Red Nasturtium received the highest scores among the four flowers in terms of taste, aroma, chewiness and color. Keywords: Edible Flowers, Development Performances, Storage