2013 ASHS Annual Conference

Growth and physiological disorders caused by abnormally high temperatures were evaluated in an important pepper field crop. In addition, chemical treatment for reducing the damages from high temperature was tested and its effect was verified using 'Binnari' (diniconazole). Shoot growth of pepper was improved as the temperature increased from 25 °C, an optimum temperature for growth, while its spasticity was low and plants cultivated at 30 °C showed relatively weak growth and development. However, root growth was not affected by the different temperatures. The number of leaf, leaf area, fresh weight, and dry weight were increased at the tempratures higher than 25 °C. Whereas, yield was decreased by 17% at 30 °C in comparison to 25 °C. Falling blossom rate was different depending on the growth temperature, and the rate of 28% at 25 °C, 33.5% at 27.5 °C, and 52.3% at 30 °C was observed, indicating that falling blossom rate increased as temperature rose. Calcium deficiency did not appeared at the optimum growth temperature, but slightly increased as the temperature goes up. Different growth temperatures did not affected on disease rate of phytopathora blight. Falling blossom was severe at abnormal temperatures higher than 30 °C, but the treatment of 'Binnari' reduced falling blossom rate and increased the yield by 10% as compared to control. The optimum concentration for 'Binnari' treatment was 10 mg/L.