Cultivation of dandelion (Taraxacum erythropodium) on coastal saline land based on the control of salinity and fertilizer

Abstract

Dandelion (Taraxacum spp.) is a widely distributed weed; in China, however, dandelion has been considered to be a kind of medicinal and edible vegetable in recent years. This transition from weed to vegetable requires corresponding cultivation and management. Thus, the production of dandelion on saline land was conducted based on the evaluation of dandelion salt tolerance. Low soil salt content (< 0.3%) did not significantly affect dandelion growth, and the salt tolerance threshold of dandelion ranged from 0.4% to 0.43% according to the correlation between salt content and morphological and physiological parameters, which was for guiding the preparation of saline land for dandelion field cultivation. Different fertilizer treatments significantly affected the leaf yield of dandelion, and the maximum fresh leaf yield of ~10.5 t ha−1 was obtained when urea was applied in batches at a ratio of 2:2:1 in the sowing, seedling and flowering stages, respectively. This research provided the theoretical and technical support for the cultivation on saline land, laying the foundation for further study of quality control for the cultivation of dandelion on saline land.

Impact of Salinity on the Growth and Chemical Composition of Two Underutilized Wild Edible Greens: Taraxacum officinale and Reichardia picroides

“…Available data on the salinity tolerance of the tested species are scarce in the literature. However, in agreement with our results, high salt content in soil (>0.7%) significantly reduced plant growth in Taraxacum erythropodium, whereas at salt content below 0.7% the declining trend weakened [45]. On the other hand, there is evidence that R. picroides is resistant to high salinity levels, as its natural habitats include saline sand dunes in the coastal areas of the Mediterranean [75], while other reports indicate the effectiveness of the species to withstand saline irrigation water of 8 dS m −1 without significantly compromising plant growth [46].…”

“…Moreover, the increased leaf K concentration (7.04% DW) determined in R. picroides compared to the leaf K (5.48% DW) of T. officinale (Table 3) could be related to the higher proline biosynthesis in R. picroides, since Chou et al [114] mentioned that proline accumulation depends on the availability of potassium. As mentioned before, in both species, proline content in EC-6 treatment did not differ from the control; however, the increase in T. officinale was more profound than that in R. picroides, a finding which is in agreement with the results of Wu et al [45], who reported that Taraxacum erythropodium plants exhibited a rapid response to the increased salinity by increasing leaf proline content. Similar results were reported by Slabbert and Krüger [115] for Amaranthus sp., Xue et al [113] for Brassica napus and Saleh [116] for Vigna radiata plants.…”

“…In general, the effect of salinity on the content and function of photosynthetic pigments in green vegetables is related to the salt tolerance of the species, the severity of the stress, the plant growth stage, the duration and the method of stress application [117]. In agreement to our results, the photosynthetic pigments content in Cichorium spinosum leaves was not affected by 20 and 40 mM NaCl [118], whereas total chlorophyll content of Taraxacum erythropodium decreased when soil salt content exceeded 0.4% [45]. The fact that the chlorophyll content was not affected even when both plants were grown under high salinity (EC-10) indicates that despite the reduced plant growth, the harvested leaves retained their greenness and thus their visual quality [119,120].…”

“…Other adaptation mechanisms include the biosynthesis of bioactive compounds (e.g., phenolic compounds) and osmoprotectants such as glutames and γ-aminobutyric acid [11]. Several studies have confirmed the tolerance of wild edible greens under environmental constraints, and species such as Reichardia picroides, Cichorium spinosum, Sonchus oleraceus and Urospermum picroides have been identified as salt tolerant and should be suggested as alternative/complementary crops or for the phytoremediation of saline soils [25,[45][46][47].…”

Allelopathic effect of marigold (Tagetes erecta L.) leaf extract on growth of Chlorella vulgaris

“…It is a kind of edible medicinal plant, and people often extract lutein from its flowers due to very high carotenoids. However, marigold leaf extract can inhibit the growth of cancer cells and bacteria mainly because of chemical compounds like flavones, chlorogenic acid, and coffee acid which functioned as antibacterial, anti-inflammatory, and antioxidant effects [10,11]. After the extraction of carotenoids from the flowers, the flower remains are discarded leading to a waste of resources.…”