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Novel approaches to the characterization of medicinal plants as biofactories have lately increased in the field of biotechnology. In this work, a multifaceted approach based on plant tissue culture, metabolomics, and machine learning was applied to decipher and further characterize the biosynthesis of phenolic compounds by eliciting cell suspension cultures from medicinal plants belonging to the Bryophyllum subgenus. The application of untargeted metabolomics provided a total of 460 phenolic compounds. The biosynthesis of 164 of them was significantly modulated by elicitation. The application of neurofuzzy logic as a machine learning tool allowed for deciphering the critical factors involved in the response to elicitation, predicting their influence and interactions on plant cell growth and the biosynthesis of several polyphenols subfamilies. The results indicate that salicylic acid plays a definitive genotype-dependent role in the elicitation of Bryophyllum cell cultures, while methyl jasmonate was revealed as a secondary factor. The knowledge provided by this approach opens a wide perspective on the research of medicinal plants and facilitates their biotechnological exploitation as biofactories in the food, cosmetic and pharmaceutical fields.

Phenolic compounds constitute an important family of natural bioactive compounds re-sponsible for the medicinal properties attributed to Bryophyllum plants (genus Kalanchoe, Crassu-laceae), but their production by these medicinal plants has not been characterized to date. In this work, a combinatorial approach including plant tissue culture, untargeted metabolomics, and machine learning is proposed to unravel the critical factors behind the biosynthesis of phenolic compounds in these species. The untargeted metabolomics revealed 485 annotated compounds that were produced by three Bryophyllum species cultured in vitro in a genotype and organ-dependent manner. Neurofuzzy logic (NFL) predictive models assessed the significant influence of genotypes and organs and identified the key nutrients from culture media formulations involved in phenolic compound biosynthesis. Sulfate played a critical role in tyrosol and lignan biosynthesis, copper in phenolic acid biosynthesis, calcium in stilbene biosynthesis, and magnesium in flavanol biosynthe-sis. Flavonol and anthocyanin biosynthesis was not significantly affected by mineral components. As a result, a predictive biosynthetic model for all the Bryophyllum genotypes was proposed. The combination of untargeted metabolomics with machine learning provided a robust approach to achieve the phytochemical characterization of the previously unexplored species belonging to the Bryophyllum subgenus, facilitating their biotechnological exploitation as a promising source of bio-active compounds.

Maintaining natural resources on western military installations has received increasing attention in recent years. Of special interest are training ranges where the environmental impact of tracked and wheeled vehicles is significant. Revegetation and soil stabilization on the arid and semi-arid regions of these western installations require special techniques. This report identifies key plant species that may be useful to installation land managers seeking to maintain or rehabilitate training lands in these areas. The plant species are described in terms of their regional and environmental adaptations, limitations, uses, establishment requirements, and availability. In addition, recommendations for short- and long-term revegetation efforts have been made for selected western installations. Keywords: Arid land; Training ranges; Vegetation; and Semi-arid land.

During the Dredged Material Research Program, six wetland and three upland habitat development projects were established at seven sites to demonstrate the feasibility of creating productive habitat on dredged material deposits. Wetland sites were Windmall Point in the James River, Virginia; Buttermilk Sound near the Altamaha River, Georgia; Drake Wilson Island in Apalachicola Bay, Florida; Bolivar Peninsula in Galveston Bay, Texas; Salt Pond Number 3 in South San Francisco Bay, California; and Miller Sands Island in the Columbia River, Oregon. Sites were also located in upland areas at Nott Island in the Connecticut River, Connecticut; Bolivar Peninsula; and Miller Sands. These sites have continued to be monitored since their construction (1975-77) until the present time. In addition, three natural marsh upland reference sites have been selected for comparison to the man-made sites. Data and research results are presented in this report. Results over an 8-year period indicate that all of the sites have developed and stabilized, and that they have all been highly successful. Despite a complete lack of management since construction, the sites maintain plant communities generally comparable to or more productive than those on the reference areas. Wildlife use exceeds that occurring on reference areas, and the sites are compatible with and contributing to the ecosystems of which they are a part. (Author)

A field and laboratory study was conducted to establish the extent of heavy metal absorption and uptake by marsh plant species from dredged material and to develop a technique using chemical extraction of heavy metals from dredged material to predict the concentration of heavy metals in marsh plants subsequently grown on the dredged material. Extensive field sampling of marsh plants and dredged material from U.S. Army Corps of Engineers (CE) disposal sites was donducted along the East and Gulf Coasts of the United States. Marsh plant species studied included Spartina alterniflora, Spartina patens, and Distichlis spicata. Four procedures for the extraction of heavy metals from soil were evaluated including water soluble, ammonium acetate exchangeable, dilute acid extractable, and DTPA extractable. Results indicated that most marsh plants colonizing dredged material disposal sites sampled in this study contained relatively low concentrations of Zn, Cu, Cd, Pb, Cr, Ni, and Hg. These concentrations were very similar to those reported for natural coastal marshes. There were a few location, however, in which the concentrations of Zn, Cu, Dc, and Pb in the marsh plants were an order of magnitude greater than the concentrations measured in the majority of marsh plants. The occurrence of these elevated concentrations of heavy metals emphasizes the need for a method to predict heavy metal availability from dredged material to plants. DTPA extraction of heavy metals gave the best correlations with actual heavy metal concentrations in marsh plants., Report on Dredged Material Research Program.