Semra Kilic

Pulse timing control for LED plant growth unit and effects on carnation

The effects of LED with different modulations on the carnation plant are investigated.Control of the pulse timing between red and blue light in PWM dimming was examined.Stomata and chlorophyll content of the carnation are examined and compared to control. In this study, the effect of LED plant growth units at different working modes on carnation is examined. The applications are performed in a tunnel-type full-automatic greenhouse environment. LED plant growth units involving red and blue LEDs at different wavelengths (Mod1, Mod2, Mod3, Mod4) are fed at different modes and their effects on carnation are observed in comparison with the control. Thus, applications are performed with four different working modes. Control of the pulse timing (phase of wave pattern) between red and blue light in PWM light dimming has been examined. Morphological and physiological changes in carnation development, growth and blooming stages have been compared among different treatments. In different light application, several changes in stomatal responses, leaf area, chlorophyll content and flowers in carnation have been observed when compared with control. We have obtained the best results in all studied parameters, especially in Mod 2 while we have obtained relatively worse results in Mod 3 implementation than the control implementation. Chlorophyll quantities in carnations are measured by the pedicle lengths of the flowers and the flower quantities and the results are compared with the carnations grown under sun in a greenhouse. The changes on growth and development of carnation exposed to different light have been determined as more sensitive parameters to detect its effects.

Response of maize (Zea mays L. saccharata Sturt) to different concentration treatments of deltamethrin.

The aim of this study was to investigate the effect of the deltamethrin pesticide on the biological properties of maize (Zea mays L. saccharata Sturt). Maize seeds were exposed to environmentally relevant dosages (0.01, 0.05, 0.1 and 0.5 ppm) of deltamethrin. On the 7th day of germination, morphological, anatomical and physiological responses were determined. All seedling growth characters were decreased with increasing deltamethrin levels. The most negative effect on the radicle length of maize was observed by the highest deltamethrin concentration with a 61% decrease (P <0.05). Both stomatal density and stomatal dimension reduction were caused by increasing concentrations of deltamethrin. Moreover, the pigments like chlorophyll a, chlorophyll b, total chlorophyll and caretonoids decreased with the increase in deltamethrin concentration. Conversely, anthocyanin and proline content increased in parallel with deltamethrin concentration. As a result, all morphological traits and pigments except for proline and anthocyanin were significantly reduced with an increase in pesticide concentration, compared to control (P <0.05).