Crossing to improve fruit yield and shape characteristics in Chili pepper

Chili pepper (Capsicum annum L.) is a self-pollinating plant from Solanaceae family and one of the most important vegetables for food and medicinal consumption. Iran is one of the regions with the highest production level of this product. Estimates of combining ability are useful in determining breeding value of chili pepper lines by proposing the correct breeding method to produce new hybrids with high yield and quality. This study was conducted to evaluate general and specific combining ability in 7 inbred lines recommended for chili pepper breeding, based on a previous research. Analysis of variance revealed significant differences among genotypes for the studied traits. The highest number of fruit per plant (145) was observed in ‘2×5’ hybrid. For fruit per plant, the highest specific and general combining abilities were observed in ‘1×5’ hybrid and line ‘2’, respectively. The highest mid- and max-heterosis for the number of fruit per plant was observed in ‘2×3’ and ‘1×4’ hybrids. The highest heterosis for fruit length and diameter was observed in ‘2×6’ hybrid. Yield heterosis is the primary target for increasing productivity but the biological complexity of yield as a trait frequently makes it difficult to draw meaningful conclusions in order to track individual causal elements involved in heterosis. Therefore, chili breeders might develop F1 cultivars based on high specific combining ability for yield-related characteristics such as fruit number per plant and fruit length. Crossing lines ‘2’ and ‘6’ are suggested for hybrid production due to high values of this hybrid for many characters related to chili pepper yield and quality.