The purpose of this study was to explore the possibilities of improving chilling stress tolerance of eggplant seedlings through exogenous melatonin (MEL) application. Eggplant (Hadrian F1) seedlings were treated with various concentrations (0, 1, 5 or 25 μM) of MEL via soil drench after which they were subjected to chilling stress at 5°C/10°C (night/day) for 3 days. Following stress imposition, the efficacy of MEL applications on enhancing chilling stress tolerance was determined by several physical and physiological measurements and biochemical analyses. The results demonstrated that exogenous application of MEL alleviated the adverse effects of chilling stress in eggplant seedlings. Among the MEL concentrations tested, 5 µM was determined as the most effective concentration since antioxidant enzyme (CAT, POX and APOX) and photosynthetic activities increased while visual and membrane damage decreased in 5 µM MEL-treated seedlings. Also, these results are the first experimental evidence that exogenous application of MEL could improve chilling stress tolerance in eggplant, but further detailed studies are necessary to better understand the mechanism in acquiring chilling tolerance.

The most important factors those are limiting the production of eggplant in Turkey and the world are soil borne fungal diseases and pests. Fusarium and Verticillium as fungal diseases and nematodes as pests cause significant yield losses. Those pathogens cause significant yield losses both in open field and greenhouse cultivation. The most efficient way to avoid those diseases is using resistant varieties or rootstocks. Although resistant genes to all these three pathogenes do not exist in eggplant cultivars, wild eggplant, Solanum torvum Sw can contain them. . However interspecific crosses cannot be achieved because of the sexual incompatibility between Solanum torvum and Solanum melongena. Thus resistant genes cannot be transferred by classical breeding. For this purpose, in order to understand the reasons of the failure in interspecific crosses, polen viability and germination percentage should be determined as a priority. For this purpose, pollen viability and germination levels of Aydın siyahı and Kemer eggplant cultivars and one wild form (Solanum torvum) were determined. Pollen viability and polen germination percentage were determined by TTC and ‘agar in Petri’ methods, respectively. In vitro reciprocal crosses were made between Kemer and Aydın Siyahı cultivars in order to obtain hybrids. In this study, in vitro embryo rescue technique was used in 25, 30 and 35 days after pollination. The embryo number obtained and plants regenerated were recorded.