The 2011 ASHS Annual Conference

Bell pepper (Capsicum annuum) production in Central America and the Caribbean has become one of the main agricultural commodities for exporting into the U.S. and the European Union. To guarantee constant supply and quality, small and medium-size growers use passively-ventilated protective structures like greenhouse and high tunnels. The main goal of those structures is to controlling the growing environment, reduce pests, and improve fruit quality and yields. Nevertheless, small and medium-size growers cannot afford using electric or diesel fans and cooling systems to lower temperatures and relative humidity, which causes increased fruit sun-scalding, lowered fruit number and size, and thus increased postharvest losses (as high as 35% in some colored peppers). For this reason, two experiments were carried out at the Dominican Republic. The first study sought to determine the effects of planting densities and flower pruning programs on yield and postharvest quality in indeterminate bell pepper grown under protected environment. The distances were 20, 25, and 30 cm between plants combined with two flower pruning programs: one flower per node (Dutch pruning), and no flower removal on each node (Spanish pruning). There was no interaction between both factors. Marketable and non-marketable fruit number and weight were the highest at 30 cm between plants, whereas the Dutch pruning showed the highest marketable fruit weight and number. For fruit quality traits, the combination of Dutch pruning and 25 cm between plants and the combination of Spanish pruning and 30 cm between plants resulted on the highest fruit weight, length, diameter, and thickness. The second study dealt with the effects of flower pruning and number of stems on yield and postharvest quality of indeterminate bell pepper under protected environment. Three pruning levels were used for this experiment: pruning up to the 10^th, 15^th, and 20^th node in combination with one and two stems.  The number of fruit, fruit yield, and number and weight of non-commercial fruit were the highest for plants with two stems. The combination of one stem and pruning either to the 10^th or 15^th node resulted on the highest fruit weight, length, diameter and thickness.