Screening Chili and Sweet Pepper Lines for Drought Tolerance and Hybrid Vigor for Leaf, Stem, and Fruit Quality Traits

Pepper (Capsicum annuum) is an important vegetable commodity grown in Florida. We are focused on developing improved pepper cultivars adapted to field production. For this purpose, we needed quick and efficient methods to screen large number of breeding lines for plant and fruit quality traits. Loss of water from leaves through transpiration is one aspect of whole plant tolerance to drought. To test variation in this trait, we screened 8 inbred lines grown in a greenhouse for the rate of water loss from excised leaves. In a 30-minute incubation period under light, excised leaves from the lines lost 13% (‘Georgia Flame’) to 19% (‘Corno di Toro’) of the initial water suggesting that this screen could be an efficient way to identify germplasm to test for whole plant tolerance to drought. To understand the degree of hybrid vigor of F1 peppers for leaf size, stem branching and fruit quality traits, controlled pollinations between pairs of plants selected from three sweet pepper inbred lines and four chili pepper inbred lines were made. Distinctly different traits in these lines for leaf size, stem branching and fruit size and shape characteristics were recorded. We expect that the methods developed in this research will improve the efficiency in pepper breeding.