The Effect of Silicon and The Status of Phenolic Compounds On The Germination of Cowpea (Vigna unguiculata L. Walp.) Under Temperature Stress

The aim of the study was to evaluate the elevated temperature on germination and seedling growth and the ameliorative effect of silicon on the phenolic compounds of black-eyed cowpea. The seeds were allowed to germinate at 30 (control), 36 and 44°C temperatures, under controlled conditions, silicons were with concentrations of 0.0 (control) and 1.5 mM. In the second phase of the experiment, some of the seeds were grown in plastic cups with sieved soil at 30 °C, 36 °C and 44 °C for phenolic compounds. Among the temperature treatments, plant deaths occurred at 44 °C. The raise in temperature importantly reduced germination and related traits. Except for SL, the seeds showed good germination at 30 °C after Si application. In high temperatures, silicon applications had a positive effect on germination and seedling growth, except for the germination rate. Results showed that an increase in GA, PA, Q, CAM, CA, PCA, SA, VA, CAF as temperatures increased. But chlorogenic acid and Q values were higher at 30 °C. This study clearly observed that the growth of cowpea seedlings decreased with temperature increase, but silicon attenuated these effects.