Effect of different shading levels on growth and yield parameters of a hot pepper (Capsicum annuum L.) cultivar 'Beldi' grown in Tunisia. (Special Issue: Tunisian fruit and vegetables.)

摘要

Pepper is one of the main vegetable crops grown and consumed in Tunisia and is therefore of economic importance. In Tunisia, 19400 ha were dedicated to this crop and its production amounted to 304000 t in 2010. Pepper production (crop yield and quality) in some Mediterranean regions is negatively affected by the high radiation, temperature and relative humidity particularly during spring-summer harvesting period. The use of shading screen is thought to be an efficient solution to overcome this problem and to improve pepper growth and yield. Therefore, the aim of this study was to evaluate the effect of different levels of shading on growth and yield parameters of the hot pepper (Capsicum annuum L.) cv 'Beldi'. For this reason, two shading levels were evaluated in order to attain 50% and 100% shading which compared to open field conditions (control 0% shading). The 50% and 100% shading levels, respectively increased total plant height by 15% and 30%, internode length by 31% and 47%, leaf area by 30% and 40%, and plant yield by 5% and 24% relative to non-shaded conditions. However, 50% and 100% shading decreased the incidence of blossom end rot by 30% and 69%, respectively relative to non-shaded pepper plants. A microclimate may have been created by the shading conditions, particularly under 100% shading, during the hottest summer period (June, July and August), has improved the vegetative growth and by extending plant physiological activity.