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Soil salinity is a well-known abiotic factor affecting the germination and seedling growth of various plant species. Therefore, we evaluated the effects of different chloride salts (NaCl, KCl and MgCl2) and sulfate salts (Na2SO4, K2SO4 and MgSO4) on the seed germination and early seedling growth of two important ethnomedicinal shrubs of North Africa and the Mediterranean basin (Ballota hirsuta and Myrtus communis). Seeds of these species were subjected to five salinity levels (0–100 mM) and incubated at 20 °C under a light regime (12 h photoperiod). Both species demonstrated their highest germination percentage under control conditions (i.e., without salinity). However, as salinity levels increased, the germination percentages for both species decreased, regardless of the type of salt used. Cations appeared to be more determinative than the anions in regulating the seed germination of both species. M. communis seeds displayed greater sensitivity to sodium (Na+) salts, especially when accompanied with chloride (Cl−) anions. At the higher salt concentrations (75 and 100 mM), Na+ salts had a more pronounced inhibitory effect on M. communis seedling growth compared to potassium (K+) and magnesium (Mg2+) salts. Conversely, Mg2+ salts were more detrimental to seedling growth in B. hirsuta. Based on our results, it can be concluded that both of these species are able to tolerate a moderate level of salinity. Overall, B. hirsuta may be a promising choice for rehabilitating the soils dominated by chloride salts, while M. communis could be utilized for restoring sulfate-dominated soils. [ABSTRACT FROM AUTHOR]

The formation of soil seed banks could be an important survival strategy for desert plant species that determine their persistence under harsh conditions, where temperature is extremely high, and chances of rainfall are low and unpredictable. Therefore, the assessment of the seed viability and germination potential of in-situ stored seeds could be important for understanding their reproductive strategies. Seeds of the studied species were collected in 2017 and divided into two batches. The first batch (fresh seeds) of each species was tested for seed germination within one week after collection. However, the second batch (in-situ stored seeds) was tested for seed germination in the first week of October 2022. In the current study, the germination potential of in-situ stored seeds was investigated in order to determine their ability to remain viable under natural conditions. Stored seeds of studied species showed higher germination percentages (53–89%) than fresh seeds (3–34%), except for Peganum harmala, indicating the presence of seed dormancy at the time of seed maturation. Seed germination percentages of all the species were significantly enhanced by storage, indicating their ability to form persistent soil seed banks, although the extent was species-specific. Fresh seeds of all the species attained higher germination in light as compared to complete darkness, suggesting that the germination of seeds can be restricted if they are buried deep in the soil under natural conditions. However, depending on species, in-situ seed storage changed the light requirement for germination. Additionally, the absence of an increase in the ratio of dead seeds between fresh and stored seeds indicates their ability to remain persistent in a soil seed bank and thus may offer great potential for maintaining and restoring desert ecosystems. [ABSTRACT FROM AUTHOR]

Aerial seed banks facilitate population persistence by extending the temporal range of seed dispersal. Knowing the temporal range of germination will improve our understanding of the relationship between seed germination dynamics and aerial seed bank storage duration. We tested the effects of temperature (12/12 h of 5/10, 10/20, 20/30 and 25/35 °C) and light variation (12 h light/12 h darkness and 24 h darkness per day) on germination of Rumex obtusifolius L. seeds retained in an aerial seed bank for 0, 2, 4, 6, 8 and 10 months. Freshly harvested R. obtusifolius were non-dormant and exhibited germination rates of up to 92%. Overall, seeds of R. obtusifolius germinated reliably at all but the lowest temperature (5/10 °C). Seeds maintained high viability throughout the collection period, indicating that fluctuating weather conditions had little influence on seed germination. Thus, the species can maintain viable seeds in aerial storage for up to 10 months and contribute viable seeds to the soil seed bank year-round. This ability to maintain a renewed soil seed bank contributes to the species' strong resilience in colonizing disturbed areas and makes it a difficult weed to control. [ABSTRACT FROM AUTHOR]

Microbial exopolysaccharides (EPSs), e.g., xanthan, dextran, gellan, curdlan, etc., have significant applications in several industries (pharma, food, textiles, petroleum, etc.) due to their biocompatibility, nontoxicity, and functional characteristics. However, biodegradability, poor cell adhesion, mineralization, and lower enzyme activity are some other factors that might hinder commercial applications in healthcare practices. Some EPSs lack biological activities that make them prone to degradation in ex vivo, as well as in vivo environments. The blending of EPSs with other natural and synthetic polymers can improve the structural, functional, and physiological characteristics, and make the composites suitable for a diverse range of applications. In comparison to EPS, composites have more mechanical strength, porosity, and stress-bearing capacity, along with a higher cell adhesion rate, and mineralization that is required for tissue engineering. Composites have a better possibility for biomedical and healthcare applications and are used for 2D and 3D scaffold fabrication, drug carrying and delivery, wound healing, tissue regeneration, and engineering. However, the commercialization of these products still needs in-depth research, considering commercial aspects such as stability within ex vivo and in vivo environments, the presence of biological fluids and enzymes, degradation profile, and interaction within living systems. The opportunities and potential applications are diverse, but more elaborative research is needed to address the challenges. In the current article, efforts have been made to summarize the recent advancements in applications of exopolysaccharide composites with natural and synthetic components, with special consideration of pharma and healthcare applications. [ABSTRACT FROM AUTHOR]

Implementing large-scale restoration programs requires in-depth understanding about the salinity tolerance of native species, especially in the Arabian Peninsula where salinity is one of the most serious problems. Seedlings of four native species, namely Vachillea pachyceras, Haloxylon salicornicum, Rhanterium epapposum, and Farsetia aegyptia, were subjected to different salinity treatments (1.6 (control), 3, 5, 7, and 10 dS/m). Survival, growth performance, biomass and proline accumulation were assessed after six months of salinity exposure. Different mineral concentrations in the shoot and root tissues were assessed before and after the salinity exposure. Our results showed that salinity influenced the growth parameters, enhanced proline accumulation and changed the contents of essential elements. However, the effects of salinity stress on the growth and other parameters were largely species-specific. Proline accumulation increased with an increase in the salinity level in all the species. However, the mineral content in the root and shoot tissues showed variation, depending on the species and the level of salinity stress. Overall. H. salicornicum appeared to be the most tolerant species, as its seedling survival (100% at EC 10), and root and shoot biomass were impacted minimally; meanwhile, F. aegyptia (16.7% seedling survival at EC 10) appeared to be highly sensitive to the salinity. Data generated from this study will be helpful in screening the suitable species according to their salinity tolerance in salt-affected areas. [ABSTRACT FROM AUTHOR]

Land degradation is one of the most important environmental problems worldwide, including in the Arabian Peninsula. In arid climatic conditions (i.e., high temperature, high evaporation, scanty rainfall and high salinity), anthropogenic factors (i.e., grazing, camping, infrastructure development, etc.) are the major causes of land degradation. Therefore, restoration of degraded lands is urgently needed to achieve sustainable development goals. Moreover, countries in the Arabian Peninsula are suffering from a lack of natural freshwater resources. Therefore, using halophytes could be an environmentally and economically viable option to overcome limited availability of fresh water by substituting the demand of portable water for irrigation as well as restoring salt-affected lands. Saline soils are common in the Arabian Peninsula, therefore, exploring the ecological and economic potential of halophytes and incorporating them in restoration projects could be a sustainable option. In this study, an attempt was made to document the uses of Arabian halophytes through a survey of the literature and prioritizing them based on their use value. Out of the 107 species studied, 4 species, namely Arthrocnemum macrostachyum (Moric.) K.Koch., Alhagi graecorum Boiss., Bassia muricata (L.) Asch. and Phragmites australis (Cav.) Trin. Ex Steud., were categorized as high priority followed by 36 species under moderate priority. However, when the priority and life form of species was considered for prioritization, three species, namely Alhagi graecorum, Arundo donax L. and Phragmites australis, ranked at the top in the priority list among perennials and Bassia muricata ranked at the top among annuals. This information could be useful for land restoration specialists to use appropriate halophyte species to achieve for different restoration objectives in salt-affected lands. However, there is a need to develop an active monitoring system that strictly concentrates on the recycling of plants that are used in phytoremediation. [ABSTRACT FROM AUTHOR]

Multifarious plant growth-promoting Bacillus strains recovered from rhizospheric soils of the Indo Gangetic plains (IGPs) were identified as Bacillus licheniformis MNNITSR2 and Bacillus velezensis MNNITSR18 based on their biochemical characteristics and 16S rDNA gene analysis. Both strains exhibited the ability to produce IAA, siderophores, ammonia, lytic enzymes, HCN production, and phosphate solubilization capability and strongly inhibited the growth of phytopathogens such as Rhizoctonia solani and Fusariun oxysporum in vitro. In addition, these strains are also able to grow at a high temperature of 50 °C and tolerate up to 10–15% NaCl and 25% PEG 6000. The results of the pot experiment showed that individual seed inoculation and the coinoculation of multifarious plant growth promoting (PGP) Bacillus strains (SR2 and SR18) in rice fields significantly enhanced plant height, root length volume, tiller numbers, dry weight, and yield compared to the untreated control. This indicates that these strains are potential candidates for use as PGP inoculants/biofertilizers to increase rice productivity under field conditions for IGPs in Uttar Pradesh, India. [ABSTRACT FROM AUTHOR]

Understanding responsible functional traits for promoting plant invasiveness could be important to aid in the development of adequate management strategies for invasive species. Seed traits play an important role in the plant life cycle by affecting dispersal ability, formation of the soil seed bank, type and level of dormancy, germination, survival and/or competitive ability. We assessed seed traits and germination strategies of nine invasive species under five temperature regimes and light/dark treatments. Our results showed a considerable level of interspecific variation in germination percentage among the tested species. Both cooler (5/10 °C) and warmer (35/40 °C) temperatures tended to inhibit germination. All study species were considered small-seeded, and seed size did not affect germination in the light. Yet, a slightly negative correlation was found between germination in the dark and seed dimensions. We classified the species into three categories according to their germination strategies: (i) risk-avoiders, mostly displaying dormant seeds with low G%; (ii) risk-takers, reaching a high G% in a broad range of temperatures; (iii) intermediate species, showing moderate G% values, which could be enhanced in specific temperature regimes. Variability in germination requirements could be important to explain species coexistence and invasion ability of plants to colonize different ecosystems. [ABSTRACT FROM AUTHOR]

Biomass gasification produces syngas, mainly comprised of CO and H2 along with H2S, CO2, N2, and tar compounds. Inorganic carbon present in syngas as CO and CO2 can be utilized for the production of several value-added chemicals including ethanol, higher alcohols, fuels, and hydrogen. However, chemical sequestration operates at a high temperature of 300–500 °C and pressure of 3–5 MPa in the presence of heavy metal catalysts. Catalyst regeneration and the maintenance of high temperature and pressure increased the cost of operation. Microorganisms like algae and bacteria including Acetobacterium and Clostridium also have the potential to sequester carbon from the gas phase. Research has emphasized the production of microbial metabolites with a high market value from syngas. However, scale-up and commercialization of technology have some obstacles like inefficient mass transfer, microbial contamination, inconsistency in syngas composition, and requirement for a clean-up process. The current review summarizes the recent advances in syngas production and utilization with special consideration of alcohol and energy-related products along with challenges for scale-up. [ABSTRACT FROM AUTHOR]

Waste rice straw biomass and its burning in open fields have become a serious issue of greenhouse gases emission and air pollution, which has a negative impact on public health and the environment. However, the environmental impact of burning this agro-waste can be mitigated by diverting it towards green biorefinery through the sustainable production of energy, biofuels, organic chemicals, and building blocks for various polymers. This will not only help to reduce the reliance on limited fuels and various chemicals derived from petroleum, but also help in the restoration of the environment in a sustainable manner through its complete utilization. To maximize the inherent conversion potential of rice straw biomass into valuable products, this agriculture waste biomass requires a comprehensive analysis and a techno-economic review for its sustainable management. This review article focuses on the sustainable management of rice straw waste biomass via innovative valorization approaches, as well as the opportunities and challenges encountered in this sector for meeting the demand of current and future green biorefineries. [ABSTRACT FROM AUTHOR]

Continuous urbanization and modernization have increased the burning of fossil fuels to meet energy needs across the globe, emanating environmental pollution and depleting fossil fuels. Therefore, a shift towards sustainable and renewable energy is necessary. Several techniques to exploit biomass to yield energy are trending, with pyrolysis one of them. Usually, a single feedstock is employed in pyrolysis for anoxygenic generation of biochar together with bio-oil at elevated temperatures (350–600 °C). Bio-oil produced through pyrolysis can be upgraded to crude oil after some modification. However, these modifications of bio-oil are one of the major drawbacks for its large-scale adoption, as upgradation increases the overall cost. Therefore, in recent years the scientific community has been researching co-pyrolysis technology that involves the pyrolysis of lignocellulosic biomass waste with non-biodegradable waste. Co-pyrolysis reduces the need for post-modification of bio-oil, unlike pyrolysis of a single feedstock. This review article discusses the recent advancements and technological challenges in waste biomass co-pyrolysis, the mechanism of co-pyrolysis, and factors that affect co-pyrolysis. The current study critically analyzes different recent research articles presented in databases such as PubMed, MDPI, ScienceDirect, Springer, etc. Hence, this review is one-of-a-kind in that it attempts to explain each and every aspect of the co-pyrolysis process and its current progress in the scientific field. Consequently, this review also compiles the remarkable achievements in co-pyrolysis and recommendations for the future. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the utilization of various agro-industrial wastes such as wheat bran, wheat husk, wheat straw, peanut powder, pomace, corn cobs, rice straw, sawdust and sugarcane bagasse for the cost-effective production of xylanase by Bacillus safensis XPS7 using the one-variable-at-a-time approach. A number of bacterial strains were isolated from different locations in the cold desert region of Himachal Pradesh, India. Among these, the hyperproducing strain designated as XPS7 was selected for optimized production of xylanase and identified as B. safensis based on 16S rDNA gene analysis. B. safensis XPS7 produced the maximum xylanase (141.28 U/mL) at 45 °C, pH 9, 24 h incubation time, 2% (w/v) wheat straw and wheat bran mixture as carbon source and 1.5% (w/v) ammonium nitrate as the nitrogen source in modified Riviere's medium. The results showed that the combination of wheat straw and wheat bran proved to be a cheap and abundant source for the hyper production of xylanase and can be used as an inexpensive base (carbon source) for large scale industrial production of enzymes. In addition, the use of waste for the economic production of enzymes will also help to minimize the environmental problems associated with the disposal of agro-industrial waste. [ABSTRACT FROM AUTHOR]

This paper is the first report on the development of a protocol that allows rapid and simplified extraction of total RNA from Artemisia annua L., an aromatic medicinal plant. This innovative protocol ensures a consistently high quantity and good quality of total RNA without any contamination of polyphenols, polysaccharides and proteins. The total RNA obtained is also free of fungal RNA even when extracted from fungal infested plants. The extraction buffer used in the proposed modified protocol was made up of non-hazardous chemicals. High concentrations of polyphenols of A. annua L. could be successfully eliminated and the prepared total RNA could be used for downstream reactions. [ABSTRACT FROM AUTHOR]