Bell pepper (Capsicum annuum L.) plant growth and fruit yield as affected by colored shade nets

Recent research in Georgia has shown that under heat stress conditions black shading nets improve bell pepper marketable fruit yield and quality. Use of colored shading nets has shown benefits in some crops although there is little information in the US on bell pepper responses to colored shade nets. The objective was to determine the effects of colored shade nets on fruit yield of bell pepper ('PS 09979325'). Experimental design was a randomized complete block with four replications and five treatments (5 shade treatments (black, red, silver, white, and uncovered) (Green-tek, Janesville, Wisconsin)). Results showed that mean and maximal air temperature and midday root zone temperature were highest in the unshaded treatment. Plant height and stem diameter were reduced in the unshaded treatment, although plant growth was unaffected by the shade net color. Chlorophyll index was lowest under the black net. The incidence of soil borne diseases was greatest in the unshaded treatment. Marketable and total fruit number and yield and individual fruit weight were reduced under unshaded treatment compared to all shading nets. There were no differences in fruit numbers and fruit yields among colored shading nets. In conclusion, bell pepper plant growth, leaf gas exchange, and fruit yield were reduced under unshaded conditions, and there were no differences in plant growth and fruit yields among colored shading nets.