## 4 Discussion
Clearly, in the red fruit, the conversion of chloroplast into chromoplast is related to both chlorophyll degradation and the increase in carotenoid biosynthesis, as already in pepper formerly by other authors [72; 73]. Grafting led to no changes in chlorophyll and carotenoid contents, despite the significant interaction found for the total chlorophyll amount in the green fruit and the carotenoid levels in the red fruit. The highest total chlorophyll level was recorded in the green fruit produced by the ungrafted \"Cuerno\" compared to the other thesis, as with the fruit produced by the grafted plants of this landrace. Conversely, for \"Sueca\" and \"Valencia\", no differences were observed in the total chlorophyll between the fruit produced by the grafted and ungrafted plants. Antioxidant capacity was negatively influenced by grafting, and was higher in both colored peppers produced by the ungrafted plants, whereas a strong influence of genotype was recorded with landrace \"Valencia\", which produced fruit with the highest antioxidant capacity (both green and red). These results evidenced that grafting did not improve fruit antioxidant capacity as reported by other authors [74] in tomato cultivar Cecilia F1, grafted onto He-man and Spirit. Our results contrast with those reported by [PERSON] et al. [18] in fruit from grafted bell peppers. What our results evidence is that red fruit, independently of landrace or grafting, had a higher antioxidant capacity compared to green ones in accordance with the data reported by [PERSON] et al. [66] in the red fruit of cultivar \"Mazurca.\"  
The correlation analysis revealed that antioxidant capacity was related only to the phenols compound in the green fruit of all the grafted landraces, but another picture appeared for the red fruit. In fact, a significant correlation between antioxidant capacity and phenols was found only for the grafted plants, but a significant contribution to antioxidant capacity was made in the red fruitby ascorbic acid. In the red fruits, an inverse correlation between antioxidant capacity and lycopene was noted as reported by [PERSON] et al. [30]. The analytical technique to analyze VOCs identified 51 different compounds. The terpenoid class includes a wide diversity of compounds with significant differences between fruit stage maturity and landraces. Most terpenids are mono- and sesquiterpenes, of which 3-carene and \(\beta\)-linaool are mainly responsible for sweetness and fresh flowery aroma, and are typical in the fruit of peppers [75] and other fruit, vegetables and food aromas [76]. These compounds were significantly present in the green fruit, with no differences among landraces for 3-carene, but a higher concentration was observed in \"Valencia\" and \"Sueca\" compared to \"Cuerno.\" Among sesquiterpenes, large amounts of copaene, \(\alpha\)-bergamotene, and \(\beta\)-farnesene appear. \(\beta\)-farnesene is involved in sweet pepper fruit flavor andappeared in large amounts in the green fruit, but with no differences among landraces. Even aldehydes, ketone, alcohols, and acids were recorded in pepper fruit and, once again, with the highest level in the green fruit as compared to the red ones. Within acids, nonanoic acid is prevalent, nonenal was the prevalent aldehyde and 2-octen-1-ol (E) and _cis_ -3 nonel -1- ol were the prevalent alcohols. Many of these compounds derive from lipids such as linolenic and linoleic acid through the action of the lipoxygenase pathway, as reported by [PERSON] et al. [77]. No differences among landraces were found for acids, but differences were noted for ethanol (higher in \"Cuerno\") among alcohols, for aldehyde nonenal (higher in \"Cuerno\" and \"Sueca\"), and also for ketones 2-heptanone (higher in \"Valencia\") and 5,5-dimethyl-1,3-dithian-2-one, which was higher in \"Cuerno\" and \"Sueca\". As formerly reported, numerous esters are found in pepper fruit [78] that typically improve fruity flavor and floral aroma in different _Capsicum_ species.