Tomato (Lycopersicon esculentum Mill.) is among the most widely consumed vegetables worldwide and an important source of certain antioxidants (AO) including lycopene, β-carotene, and vitamin C. Improvement of tomato for content of AO and overall antioxidant activity (AOA) could potentially benefit human health in many countries. We evaluated 50 L. esculentum and three L. pimpinellifolium (L.) Mill. entries for contents of lycopene, β-carotene, ascorbic acid, total phenolics, and two assays for antioxidant activity [anti-radical power (ARP) and inhibition of lipid peroxidation (ILP)] for 2 years during the same period in south Taiwan. We detected high levels of genetic diversity for the AO and AOA measured in this study. Group means of the L. pimpinellifolium entries were significantly higher than L. esculentum group means for ARP, ILP, lycopene, ascorbic acid, phenolics, and soluble solids concentration, suggesting that introgression of alleles from L. pimpinellifolium may have potential to improve cultivated tomato for these traits. Ranking of entries for ILP and ARP were consistent between years, particularly for those entries with the highest means and these assays could be adopted by tomato breeders. Results from ILP and ARP assays were highly correlated (r = 0.82**) and it would be unnecessary to use both assays for tomato. Lycopene, β-carotene, ascorbic acid, soluble solids, and total phenolics were all positively correlated with ARP. Among AO, total phenolics content was most closely associated with ARP (r = 0.90**) and ILP (r = 0.83**); this suggests that phenolics make a major contribution to AOA in tomato fruit. Fruit size was negatively correlated with ARP (r = -0.74**) and ILP (r = -0.71**), indicating that combining large fruit size and high AOA will be challenging.

Pepper (Capsicum sp.) is important in human diets in many parts of the world and a major source of several antioxidants, including carotenoids, ascorbic acid, tocopherols and phenolics. More information on genetic diversity within Capsicum for antioxidant (AO) content and antioxidant activity (AOA) could contribute to improved human health. We evaluated 46 Capsicum accessions from AVRDC-the World Vegetable Center Capsicum core collection for content of nine AO (five carotenoids, ascorbic acid, tocopherols a and g, and total phenolics) and two AOA assays for 2 years in south Taiwan. Ample genetic diversity exists within C. annuum to increase AO content. Based on dry weight values, non-pungent C. annuum entries as a group were significantly greater than pungent entries for contents of b-cryptoxanthin (36%), ascorbic acid (65%), total phenolics (36%) and a-tocopherol (11%). Group means of the brown-fruited entries exceeded the means of red-fruited entries for capsanthin (34%), zeaxanthin (37%), lutein (36%), b-cryptoxanthin (71%), b-carotene (82%), ascorbic acid (19%) and a-tocopherol (40%). Red-fruited C. annuum entries 'Verdano Poblano' and 'Guajillo Ancho' from Mexico ranked among the entries highest for all carotenoids, ascorbic acid and a-tocopherol. The inhibition of lipid peroxidation (ILP) assay could be adopted for AOA characterization or selection because of high variation among entries and consistent entry performance over years. ILP was positively correlated with phenolics (r ¼ 0.72**) and ascorbic acid (r ¼ 0.58**) contents. Significant positive correlations were detected between most carotenoids as well as a significant positive correlation between ascorbic acid and total phenolics contents (r ¼ 0.78**).

ABSTRACT. Fruit lycopene content and total soluble solid content are important factors determining fruit quality of tomatoes; however, the dynamic quantitative trait loci (QTL) controlling lycopene and soluble solid content have not been well studied. We mapped the chromosomal regions controlling these traits in different periods in F 2:3 families derived from a cross between the domestic and wild tomato species Solanum lycopersicum and S. pimpinellifolium. Fifteen QTLs for lycopene and soluble solid content and other related traits analyzed at three different fruit ripening stages were detected with a composite interval mapping method. These QTLs explained 7-33% of the individual phenotypic variation. QTLs detected in the color-changing period were different from those detected in the other two periods. On chromosome 1, the soluble solid content QTL was located in the same region during the color-changing and full-ripe periods. On chromosome 4, the same QTL for lycopene content was found during the colorchanging and full-ripe periods. The QTL for lycopene content on chromosome 4 co-located with the QTL for soluble solid content during the full-ripe period. Co-location of lycopene content QTL ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (4): 3696-3710 (2012) QTL analysis in S. lycopersicum x S. pimpinellifolium cross 3697and soluble solid content QTLs may be due to pleiotropic effects of a single gene or a cluster of genes via physiological relationships among traits. On chromosome 9, the same two QTLs for lycopene content at two different fruit ripening periods may reflect genes controlling lycopene content that are always expressed in tomato fruit development.