Investigation of the effects of priming treatments on naturally aged anatolian black pine (Pinus nigra subsp. pallasiana) seeds

The present study was carried out to reverse the effects of natural aging due to storage by priming applications in black pine (Pinus nigra subsp. pallasiana) seeds. Total of 9 different black pine seeds, which were collected from Gölhisar, Eğirdir, Isparta and Dinar locations between 2008-2019, were obtained from Eğirdir Forest Nursery Directorate. The study was carried out in the laboratories of Faculty of Forestry and Faculty of Agriculture of Isparta University of Applied Sciences. Germination percentage, mean germination time, normal and abnormal seedling percentages, seedling and root lengths were determined during the germination studies. To determine the effects of storage time on germination and seedling characteristics, pine seeds were germinated at 25 °C for 14 days, three of which (2008, 2015, 2019) were chosen based on their germination percentages, and used for priming studies. Priming applications consisted of 3 applications (ascorbic acid, calcium chloride, potassium chloride) with 2 doses (2%, 3%) applied for 6, 12 and 24 h. Among the application times, 24 h application time was found to be more effective than 6 and 12 h application times. Among the priming applications, ascorbic acid and calcium chloride applications were more effective than potassium chloride application based on germination results. Between the application doses, 3% ascorbic acid and 2% calcium chloride applications were more effective than other doses. To determine the effects of priming applications on seeds, total soluble protein, tocopherol, free fatty acids, malondialdehyde, hydrogen peroxide contents, and superoxide dismutase and peroxidase enzyme activities were investigated. All investigated parameters were significantly affected by the storage time and priming applications, and it was also found that the effects of ascorbic acid and calcium chloride applications were different.