Low Tunnels and Shading Influence Total and Marketable Yield of Bell Pepper Fruit

In Utah, bell pepper fruit losses are often attributed to sunburn, resulting in large numbers of culls that reduce the overall value of the crop. We evaluated biological and mechanical approaches to reduce fruit losses on pepper varieties with superior fruit quality.  The effect of low tunnels and shading on pepper varieties Aristotle and Paladin were evaluated during Summer 2012 in Northern Utah. The varieties were planted in a single bed (north-south orientation), furrow irrigated system, managed using commercial production practices.  Perforated plastic low tunnels (±) were used during plant establishment and after fruit set shade cloth (±) was installed over the west side of each row. Tunnels were tested to improve early season growth (leaf cover) and shade was used to reduce heat load during the afternoon. Total and red marketable yields were higher with Aristotle regardless of treatment. Low tunnels increased total yield in both varieties when compared with the uncovered plots. Shading increased marketable red yield in Paladin but had mixed results with Aristotle. In general, lower total yields were seen in the shade treatments however, the yield of cull fruits decreased significantly with shading for both varieties. In conclusion, low tunnels increased total yield while shading increased marketable yields by reducing the number of culls.