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Suaeda edulis (Flores Olvera & Noguez) is a halophile species that grows in saline environments, with concomitant difficulties to germinate and reproduce. Once a null germination under a salinity gradient or fresh water was observed, a plant-growth bioregulator (BioR) was applied to interrupt dormancy and improve germination in vitro. This BioR is composed of gibberellins and adjuvant regulators; and 12.5, 25.0, and 37.5 mg L−1 of gibberellins with immersion at 24, 48, and 72 h were assayed. Most of the normality and homoscedasticity tests were favorable, except in three of 24 cases. On the germination percentage (transformed values), the dose 25.0 mg L−1 reflected the highest values of 5.5 and 6.0 units at 48 and 72 h. For the mean germination time, the highest level of 37.5 mg L−1 at 24 h reflected the best response. For the germination rate, the best one was 25 mg L−1 at 48 h, reaching 12% per day, but for the germination speed coefficient, the best value was observed with 25.0 mg L−1 at 24 h. It was concluded that to improve germination of S. edulis seeds, it is necessary to assess a dose-gradient of gibberellins, starting at 25.0 mg L−1, with higher values to break dormancy.

Halophytes are capable of growing in saline environments. However, this attribute results from a wide genetic variability, making it difficult to approximate halophytes’ agroecological management. We examined the hydro-climatological attributes associated with the distribution of species of the genus Suaeda in NW Mexico and SW USA, and for S. edulis in central México. The analysis focused on the introduction of the semi-domesticated species Suaeda edulis as a new crop, from central regions of México, reaching an average yield of 8 Mg ha−1 of biomass, to arid NW México. The list of Suaeda species was elaborated from the eHALOPH and Calflora databases, and the NW México Herbarium Network. According to the Hydro-Environmental Availability Index (HEAI), the central regions of Mexico reflect a greater water availability, suitable for S. edulis. In such a humid region, HEAI varied from 6 to 18, indicating sufficient moisture for crops. In contrast, other Suaeda species, including S. nigra, S. esteroa, and S. californica, spread in NW Mexico and SW United States, where the water availability is null during the year, with HEAI scoring from 0 to 4. Under such dryness, S. edulis in NW Mexico will require water through optimized irrigation and plant breeding strategies to ensure its viability as a new crop.

The objective of this study was to compare the morphology of M. spicata and R. officinalis plants, and the relative abundance quantification, colony-forming units, ribotypes, and biofilm former bacteria under an inorganic fertilizer and the use of vermicompost leachate in the rhizosphere under a closed hydroponic system. In mint (Mentha spicata) plants treated with the vermicompost leachate, growth increase was determined mainly in root length from an average of 38 cm in plants under inorganic fertilizer to 74 cm under vermicompost leachate. In rosemary (Rosmarinus officinalis), no changes were determined between the two treatments. There were differences in the compositions of microbial communities: For R. officinalis, eight ribotypes were identified, seven for inorganic fertilizer and four for vermicompost leachate. For M. spicata, eight ribotypes were identified, three of them exclusive to vermicompost leachate. However, no changes were observed in microbial communities between the two treatments. Otherwise, some changes were observed in the compositions of these communities over time. In both cases, the main found phylum was Firmicutes, with 60% for R. officinalis and 80% for M. spicata represented by the Bacillus genus. In conclusion, the use of vermicompost leachate under the hydroponic system is a viable alternative to achieve an increase in the production of M. spicata, and for both plants (mint and rosemary), the quality of the product and the microbial communities that inhabited them remained unaltered.

Attenuators of salt-stress favor the use of effluents, being a low-cost organic product. The present study aimed to evaluate the effect of vermicompost leachate (VL) added to shrimp-culture effluent on seeds and seedlings of Salicornia bigelovii (Torr.) under salt-stress, evaluating germination, water relations variables, and biomass. Seeds were irrigated with distilled water (DW) (CE: 0.0027 dS m−1), freshwater (FW) (CE: 1.36 dS m−1), seawater (SW) (CE: 55.83 dS m−1), shrimp residual water (SRW) (CE: 59.85 dS m−1), and with the same water sources but adding VL in 1:20 v/v. The means for the index of germination rate (IGR), germination energy (GE), and germination time (MGT) were higher with DW, DWVL, FW, and FWVL, decreasing with the others (p ≤ 0.05). In seedlings, the lowest water potential (Ψw) and osmotic potential (Ψs) were observed with SW, SWVL, SRW, and SRWVL (p ≤ 0.05), evidencing higher stress but the highest relative water content (RWC). The fresh and dry biomass increased and showed significant differences with SRW, and adding VL (DWVL, FWVL, SWVL, and SRWVL) acted as an effective attenuator of salt-stress. The response of water relations variables suggested an osmotic adjustment for mitigating the salt-stress in seedlings, lowering the Ψw and Ψs but increasing the RWC.

In the present study, the following was investigated: (a) The effect of ulvan on in vivo and in vitro biocontrol of Debaryomyces hansenii and Stenotrophomonas rhizophila against Fusarium proliferaum and (b) the effect of ulvan on in vivo and in vitro growth of D. hansenii and S. rhizophila and muskmelon quality parameters. The results showed that the biocontrol activity of D. hansenii and S. rhizophila could be enhanced by ulvan (5 g/L). The combination of ulvan and S. rhizophila resulted in a more effective control of fruit rot in comparison to fungicide benomyl. On in vitro growth of F. proliferatum, individual treatments of D. hansenii and S. rhizophila inhibited spore germination and mycelial growth with no statistical difference with the combined treatments. Ulvan does not have a direct effect on the in vivo and in vitro growth of D. hansenii and S. rhizophila. Furthermore, the combined treatments improve the natural disease incidence and quality parameters like weight, firmness, total soluble solids (TSS), and pH. These results suggest that the use of ulvan may be an effective method to improve the biological activity of D. hansenii and S. rhizophila.