Interest in the cultivation of lettuce landraces is increasing because native varieties, as high-quality products, are particularly attractive to consumers. Lettuce is a popular leafy vegetable worldwide, and interest in the consumption of first leaves (microgreens) and seedlings (baby leaves) has grown due to the general belief that young plants offer higher nutritional value. The content of some bioactive compounds and antioxidants (chlorophylls, carotenoids, anthocyanins, ascorbic acid, phenols, antioxidant activity) was monitored in six lettuce landraces and five commercial varieties, and compared across three development stages: microgreen, baby, and adult. Ascorbic acid and phenolic contents were 42% and 79% higher, respectively, in the early stages than in adult lettuces, and red-leaf varieties (CL4 and L11) stood out. This finding agrees with lettuce’s marked antioxidant capacity and correlates with its pigment contents, especially anthocyanins. The nutritional value of adult lettuce is conditioned by its size, shape, and head structure as phytochemical concentrations are regulated by light. The low content of ascorbic acid, phenolics, and anthocyanins in crisphead lettuce (CL5) is a clear example (49, 67%, and 27% lower, respectively, than the adult mean). Our results indicate the wide variability of lettuces’ nutritional characteristics and emphasize that traditional varieties are a helpful source of agricultural biodiversity.

Solanum pimpinellifolium and Solanum lycopersicum var. cerasiforme represent a valuable tool for tomato breeding, particularly for tolerance to abiotic stresses. Water stress and salinity are major constraints to tomato’s cultivation, and for which limited genetic variability has been reported within the cultivated species. We evaluated four accessions of S. pimpinellifolium and four of S. l. var. cerasiforme for their adaptation to water deficit and salinity. The CO₂ assimilation rate, stomatal conductance, substomatal CO₂ concentration, transpiration rate, and leaf chlorophyll concentration were evaluated, as well as morphological and agronomic traits. The accessions showed a remarkable inter- and intra-species response variability to both stresses. Two S. pimpinellifolium accessions and one S. l. var. cerasiforme showed unaltered physiological parameters, thus indicating a good adaptation to water deficit. Two S. l. var. cerasiforme accessions showed an interesting performance under salt stress, one of which showing also good adaptation to water stress. In general, both stresses showed a negative impact on leaf size and fruit fresh weight, especially in the big-sized fruits. However, flowering, fruit setting and earliness remained unaltered or even improved when compared to control conditions. Stressed plants yielded fruits with higher ° Brix. Response to stresses seemed to be linked to origin environmental conditions, notwithstanding, variability was observed among accessions of the same region.

Sweet pepper is one of the most important economic fruits with nutritional attributes. In this sense, the nutraceutical value of consumed products is a major concern nowadays so the content of some bioactive compounds and antioxidants (phenols, ascorbic acid, lycopene, carotenoids, chlorophylls, and antioxidant activity) was monitored in 18 sweet pepper landraces at two maturity stages (green and red). All the traits except chlorophylls significantly increased in red fruits (between 1.5- and 2.3-fold for phenols, ascorbic acid, and 2-2-diphenyl-1-picrylhydrazyl (DPPH) inhibition activity, 4.8-fold for carotenoid and 27.4-fold for lycopene content), which suggests that ripening is key for obtaining desired fruit quality. Among landraces, P-44 in green fruits is highlighted for its content in carotenoids, chlorophylls, phenols, and ascorbic acid, and P-46 for its antioxidant capacity and lycopene content. Upon maturity, P-48, P-44, and P-41 presented higher levels of phenols and lycopene, and P-39 of phenols, carotenoid, and DPPH. This work reflects a wide variability in the 18 pepper landraces at bioactive compounds concentration and in relation to fruit ripeness. The importance of traditional landraces in terms of organoleptic properties is emphasized as they are the main source of agricultural biodiversity today and could be helpful for breeders to develop new functional pepper varieties.

Nowadays the cultivation and consumption of traditional lettuce varieties are growing as they are particularly appealing to consumers for their diversity, and high nutraceutical quality. However, lettuce is a highly perishable product, which results in significant nutritional loss from harvest to final consumers. In this work, the content of some bioactive compounds (chlorophylls, carotenoids, anthocyanins, ascorbic acid, phenols), overall antioxidant capacity and mineral content was monitored in five landraces and four commercial lettuce varieties to compare their variation during the storage period. Visual characterization was conducted during the postharvest period, as was the determination of the parameters indicative of oxidative stress, to establish the preservation capacity of their physico-chemical attributes. As a general trend, lettuce varieties showed individualized behavior during the postharvest period, which was not necessarily better in the commercial varieties compared to the landraces. Of all the varieties, landrace L10 stood out for not showing excessive variations in its general appearance or nutritional quality throughout its life cycle. However, in terms of initial concentration of bioactive compounds, the reddest varieties (CL4 and L11) stand out. These results indicate variability among varieties, which emphasizes the potential of lettuce landraces in postharvest practices.

Traditional vegetable varieties constitute an important reservoir of biodiversity, so recovering, cultivating, and correctly classifying these landraces is part of key global heritage for the future of food security. In this study, 17 traditional pepper varieties from the Valencian Community (Spain) were characterized using 14 quantitative and 30 qualitative conventional morphological descriptors, including plant, flower, and fruit traits, in two ripening stages: green and red. As a result, landraces were grouped based mainly on their fruit morphology (G1: thin and elongated; G2: thick and robust; P-49: ball pepper). During a second trial, the preservation of the described characteristics was checked, and the number of fruit produced per plant was determined. From the acquired information, the most desirable traits that could be of interest for cultivation and harvesting practices were established, including erect growth habit, dense branching, big leaves, and uniformity and low persistence of fruit. Additionally, based mainly on fruit size and fruit wall thickness traits, the varieties with the highest potential to be marketed as fresh, P-37 (from G2), P-41, and P-72 (from G1), were determined. The ungrouped P-49 variety is an optimal candidate for industry processes because of its small size and robust fruit wall. The importance of phenotyping studies for preserving plant varieties is emphasized.