Given the important medicinal and nutritional value of wild edible greens, the last few years there is an increasing interest for their domestication and commercial exploitation. However, information concerning their adaptation to environmental conditions and their response to modern agricultural systems are scarce. In the present study, the effect of nutrient solution pH (4.0, 5.5 and 7.0) on the growth, chemical composition and inorganic nutrition of Taraxacum officinale and Reichardia picroides plants grown indoors in a floating hydroponic system was evaluated. Both species performed better at pH 5.5 and were slightly affected by pH 7.0, whereas pH 4.0 was not prohibitive for growth for both species, although R. picroides was less tolerant than T. officinale at low pH. Moreover, pH 4.0 did not severely affect nutrients uptake and transport within the plant tissues, suggesting that R. picroides susceptibility to low pH should not be attributed to nutrients imbalance. Nevertheless, low pH positively enhanced the content in total soluble solids, total phenolics, chlorophylls (a, b and total) and carotenoids, and decreased nitrates in both species. In conclusion, the studied species could be successfully grown in soilless systems with nutrient solutions of varied pH. Moreover, low pH levels (pH = 4.0) seemed to be beneficial to nutritional and dietary value in both species highlighting the potential of commercial cultivation under adverse conditions, especially in sustainable farming systems.

Lupinus mutabilis is an important source of protein in different Andean countries, and its use in diets, particularly those of less wealthy individuals, has been observed for thousands of years. There is an increasing demand for protein crops suitable for Europe and this species is a potential candidate. Assessment of Lupinus mutabilis genetic material in European conditions started more than 40 years ago, with the characterization of a vast number of accessions from the Andean region. In this review, abiotic and biotic constraints to L. mutabilis cultivation in European soil and climatic conditions are discussed, and cultivation management practices are suggested. The beneficial interaction of L. mutabilis with Bradyrhizobium strains in the soil and various pollinator species is also discussed, and the effect of abiotic stresses on these interactions is highlighted. Prospects of alternative uses of L. mutabilis biomass in Northern Europe and opportunities for breeding strategies are discussed. In conclusion, the different approach to crop modeling for Southern and Northern European climatic conditions is highlighted.

Soil salinization is one of the major environmental factors responsible for limited crop production throughout the world. Therefore, there is urgent need to find tolerant/resistant species to exploit in commercial cultivation systems. In this context, the valorization of wild edible greens for human consumption and/or medicinal purposes is gaining more and more interest. The aim of the present work was to study the effect of salinity, e.g., electrical conductivity: 2 mS cm⁻¹ (nutrient solution EC), 6 mS cm⁻¹ and 10 mS cm⁻¹ on plant growth and chemical composition of Reichardia picroides and Taraxacum officinale plants grown in a floating hydroponic system. The results showed that R. picroides is a moderately salt-tolerant species, as the majority of plant growth parameters determined were not negatively affected under the treatment of 6 mS cm⁻¹. On the other hand, the growth parameters of T. officinale plants were severely affected under the same conditions. Moreover, high salinity levels (EC at 10 mS cm⁻¹) impaired the growth of both species. The content of leaves in chlorophylls (a, b and total), carotenoids+xanthophylls and total soluble solids was not significantly affected by the tested EC levels in both species, whereas the titratable acidity increased under the treatment of 10 mS cm⁻¹. Moreover, R. picroides exhibited a more effective adaptation mechanism against saline conditions than T. officinale, as evidenced by the higher accumulation of osmolytes such as proline and the higher shoot K content, probably through a more efficient K/Na selectivity. In conclusion, both species were severely affected by high salinity; however, R. picroides showed promising results regarding its commercial cultivation under moderate salinity levels, especially in regions where resources of high-quality irrigation water are limited.

Sea daffodil is a perennial medicinal plant with several beneficial health properties that is enlisted as an endangered and protected species. For the exploitation and conservation of such valuable species, sustainable propagation is a key factor. For this purpose, the establishment of in vitro cultures using botanical seeds is an effective way to produce a large number of microplants which can be used as propagating material and/or bulblets with further uses for the isolation–production of biocactive substances. In this work, we performed two separate experiments where we studied (a) the effect of temperature (10 °C, 15 °C, 20 °C, 25 °C, and 30 °C) on seed germination in vitro and (b) the effect of temperature (10 °C, 20 °C, and 30 °C) and sucrose concentration (40 and 80 g/L) in growth medium on microplant development and the production of bulblets. Seed germination rates were high (over 70%) at a wide range of temperatures (15–30 °C), although the fastest and the most uniform germination was observed at 20–25 °C. Regarding the effect of temperature on microplant development and bulblet production, low temperatures (10 °C) had a negative effect on the number of leaves, bulb diameter, and fresh weight (F.W.) and dry weight (D.W.) of leaves, roots, and bulblets. The best growth of microplants (number of leaves, F.W. and D.W. of leaves, roots) and bulblet production (diameter, F.W., and D.W.) were observed in culture media with sucrose concentration 40 g/L and temperature of 30 °C. In culture medium with a sucrose concentration of 80 g/L the production of bulbs (diameter, F.W., and D.W.) was not inferior to culture media with a sucrose concentration of 40 g/L, although microplants had less root growth. It is concluded that the best treatment for the production of well-rooted microplants with large bulblets that could be used as propagating material or for the production of bulblets as a source for twin scales explants or pharmaceutical substances was the culture at 30 °C in culture medium with sucrose concentration 40 g/L. On the other hand, culture medium with a sucrose concentration of 80 g/L at 30 °C or 20 °C could be also used for the production of bulblets.

The cultivation of tolerant species with low-quality irrigation water is one of the main strategies to address the lack of availability of irrigation water. In this work, the effect of salinity on plant growth, nutritional composition, and quality features of Hedypnois cretica and Urospermum picroides was tested. Fresh yield of leaves and roots of both species were severely decreased under high salinity, while the mineral profile of leaves and roots also showed a decrease in most minerals. The recorded values of K/Na and Ca/Na ratios indicate that H. cretica has a higher susceptibility to salt stress due to a higher decrease in the values of the respective ratios compared to U. picroides. Leaf pigments and total phenolic compounds content were not significantly affected by salinity, while total soluble solids and titratable acidity increased under increasing salinity in most cases. Moreover, free proline content increased with increasing salinity, while the opposite trend was recorded for nitrates’ content. In conclusion, our findings indicate that tailor-made nutrient solutions could allow the use of irrigation water of a low quality for the commercial cultivation of H. cretica and U. picroides, thus allowing their domestication and integration in cropping systems where the cultivation of conventional crops is compromised.