Spatial Structure and Genetic Variation of a Mangrove Species (Avicennia marina (Forssk.) Vierh) in the Farasan Archipelago

Avicennia marina (Forssk.) Vierh is distributed in patches along the Farasan archipelago coast and is the most common mangrove species in the Red Sea. However, to date, no studies have been directed towards understanding its genetic variation in the Farasan archipelago. In this investigation, genetic variations within and among natural populations of Avicennia marina in the Farasan archipelago were studied using 15 microsatellite markers. The study found 142 alleles on 15 loci in nine populations. The observed (Ho) and expected (He) heterozygosity values were 0.351 and 0.391, respectively, which are much lower than those of earlier studies on A. marina in the Arabian Gulf. An inbreeding effect from self-pollination might explain its heterozygote deficiency. Population genetic differentiation (FST = 0.301) was similar to other mangrove species. Our findings suggest that the sea current direction and coastal geomorphology might affect genetic dispersal of A. marina. The more isolated populations with fewer connections by sea currents exhibited lower genetic variation and differentiation between populations. The genetic clustering of populations fell into three main groups—Group 1 (populations of Farasan Alkabir Island), Group 2 (populations of Sajid Island), and Group 3 (mix of one population of Farasan Alkabir Island and a population of Zifaf Island). More genetic variation and less genetic differentiation occurred when the population was not isolated and had a direct connection with sea currents. Both of these factors contributed to limited propagule dispersal and produced significant structures among the population. It is expected that the results of this research will be useful in determining policy and species-conservation strategies and in the rehabilitation of A. marina mangrove stands on the Farasan islands in an effort to save this significant natural resource

Taxonomic revision of Ceropegia sect. Huernia (Asclepiadoideae, Apocynaceae) in Saudi Arabia with three new combinations

This study provides a taxonomic revision for Ceropegia sect. Huernia in the flora of Saudi Arabia. Forty-six quantitative and qualitative morphological characters were analysed using principal component analysis (PCA), principal coordinates analysis (PCoA) and the unweighted pairs group using mean average (UPGMA) to separate and help delimit taxa. We propose to reduce the number of species reported in Saudi Arabia from 11 to four: C. khalidbinsultanii comb. nov., C. laevis, C. lodarensis and C. macrocarpa. This study also suggested reducing two names to varietal level under C. lodarensis (var. foetida comb. nov. and var. rubrosticta comb. nov.). A key to the species, detailed morphological descriptions, illustrations, distribution maps, ecology, etymology and preliminary conservation assessments are provided that follow IUCN criteria

Gene Losses and Plastome Degradation in the Hemiparasitic Species Plicosepalus acaciae and Plicosepalus curviflorus: Comparative Analyses and Phylogenetic Relationships among Santalales Members

The Plicosepalus genus includes hemiparasitic mistletoe and belongs to the Loranthaceae family, and it has several medicinal uses. In the present study, we sequenced the complete plastomes of two species, Plicosepalus acaciae and Plicosepalus curviflorus, and compared them with the plastomes of photosynthetic species (hemiparasites) and nonphotosynthetic species (holoparasites) in the order Santalales. The complete chloroplast genomes of P. acaciae and P. curviflorus are circular molecules with lengths of 120,181 bp and 121,086 bp, respectively, containing 106 and 108 genes and 63 protein-coding genes, including 25 tRNA and 4 rRNA genes for each species. We observed a reduction in the genome size of P. acaciae and P. curviflorus and the loss of certain genes, although this reduction was less than that in the hemiparasite and holoparasitic cp genomes of the Santalales order. Phylogenetic analysis supported the taxonomic state of P. acaciae and P. curviflorus as members of the family Loranthaceae and tribe Lorantheae; however, the taxonomic status of certain tribes of Loranthaceae must be reconsidered and the species that belong to it must be verified. Furthermore, available chloroplast genome data of parasitic plants could help to strengthen efforts in weed management and encourage biotechnology research to improve host resistance

Comprehensive analysis and implications of Veronica persica germination and growth traits in their invasion ecology

Abstract Invasive alien species implications in ecological threats are attributed to their unique characteristics that are linked to their invasion. Veronica persica (Plantaginaceae family) is an alien weed species in Egypt. Regardless of its widespread globally in various regions, the growth traits and behavior of V. persica remain poorly understood. The comprehensive analysis, reveals the optimal germination (Gmax) was detected at 10/20 °C, 15/20 °C, and 20/25 °C at the moderate temperature regimes. The rapid germination rate (G rate) peaked at 10/20 °C regime, with a rate of 0.376 per day. Furthermore, under stress conditions, V. persica has 50% germination inhibition (G50) and 50% of growth inhibition occurred at − 0.91 MPa and 0.75 MPa of osmotic pressure and 3225.81 ppm and 2677.1 ppm of salt stress (NaCl) respectively. The germination ranged from 6 to 9 pH, with the highest germination percentage occurring at a pH of 7 & 8, reaching 88.75% compared to the control group. There is a strong interaction effect between habitats and plant stages, the plant stages and habitats have significant effects (p ≤ 0.00) on V. persica growth. There was high and moderate plasticity in the response of morphological and growth features between stages. During the seedling-juvenile interval and the juvenile-flowering stages, respectively, there was a noticeable increase in both Relative Growth Rate and Net Assimilation Rate. Demographic surveys identified approximately 24 species across 11 families associated with V. persica in invaded areas. The Sorenson indices of qualitative index exhibited high similarity values in the invaded sites by (82.35%) compared to (72.72%) in non-invaded sites. However, interactions with native communities were reflected in lower richness, diversity, and evenness, displaying slightly higher Simpson index 1 (λ) values compared to invaded and non-invaded sites (0.043 and 0.0290) vs. (0.0207 and 0.268), in rangelands and F. carica orchards respectively. These results emphasize the substantially higher adaptability of V. persica to variable environmental conditions and abilities to invade a new community. This knowledge about invasive V. persica weeds germination and growth is itemized as the consistent predictive base for future invasion and informs strategic management priorities

Seasonal environmental cooling benefits of urban green and blue spaces in arid regions

Green and blue spaces are vital for mitigating urban heat island impacts but are poorly studied in arid regions. In this study, we quantify monthly and seasonal cooling for five contrasting types of green and blue infrastructure (GBI): rivers, lakes, "captured" agricultural areas, urban parks, and golf courses in the Cairo and Giza provinces of Egypt. Using Landsat-8 images of Land Surface Temperature (LST) we assessed change in LST along bisecting transects and in circle plots for three replicates of each GBI type, in each of four seasons. Cooling was greatest in summer for all GBI types. Cooling differentials of LST were greater for water bodies than for green spaces. Ordered by increasing cooling potential (May LST cooling) they were: Agricultural areas (3.3 °C), Golf courses (4.3 °C), Parks (4.4 °C), Lakes (8.2 °C) and Rivers (12.2 °C). The cooling effects extending into adjacent buffer areas were greatest for blue spaces like rivers and lakes. This paper provides the first data for cooling by less-studied GBI types in arid regions, such as golf courses and urban agriculture. It provides information to support city planners to embrace green and blue spaces within metropolitan areas and to protect them from urban sprawl

Assessing the suitability of pitaya plant varieties for cultivation in the arid climate of Saudi Arabia

Pitaya, sometimes called dragon fruit, is a tropical fruit crop that has become more well-known recently because of its distinct flavor and beneficial properties. However, it has only been cultivated in tropical and subtropical areas, and nothing is known about whether it can thrive in arid climates. This study considers various pitaya plant types' morphological, physiological, and agronomic aspects to assess their viability for cultivation in desert regions. This study investigated the growth and development of two cultivars of pitaya plants, S. undatus and S. costaricensis, in the Asir region of Saudi Arabia. Different fertilisation treatments were applied to determine the most effective approach for promoting growth and productivity. Results showed that the Klebak fertiliser, which contains marine algae rich in auxins and amino acids, was the most effective treatment for S. undatus. For S. costaricensis, the Klebak fertiliser was also effective, but treating tree leaves with volcanic stone was also beneficial. The volcanic stone helped to preserve moisture in the soil and promote good drainage, while the leaves provided important organic nutrients for growth. In addition, S. costaricensis was found to be more resistant and responsive to cultivation, likely due to its original habitat in the temperate climate of Mexico. These findings can help inform the cultivation of pitaya plants in similar climatic conditions. They may have implications for other areas seeking to promote the growth and productivity of this important crop

Preparation and Characterization of Super-Absorbing Gel Formulated from κ-Carrageenan–Potato Peel Starch Blended Polymers

κ-carrageenan is useful for its superior gelling, hydrogel, and thickening properties. The purpose of the study was to maximize the hydrogel properties and water-absorbing capacity of κ-carrageenan by blending it with starch from potato peels to be used as safe and biodegradable water-absorbent children’s toys. The prepared materials were analyzed using FTIR and Raman spectroscopy to analyze the functional groups. Results showed that there was a shift in the characteristic peaks of starch and κ-carrageenan, which indicated their proper reaction during blend formation. In addition, samples show a peak at 1220 cm−1 corresponding to the ester sulfate groups, and at 1670 cm−1 due to the carbonyl group contained in D-galactose. SEM micrographs showed the presence of rough surface topology after blending the two polymers, with the appearance of small pores. In addition, the presence of surface cracks indicates the biodegradability of the prepared membranes that would result after enzymatic treatment. These results are supported by surface roughness results that show the surface of the κ-carrageenan/starch membranes became rougher after enzymatic treatment. The hydrophilicity of the prepared membranes was evaluated from contact angle (CA) measurements and the swelling ratio. The swelling ratio of the prepared membranes increased gradually as the starch ratio increased, reaching 150%, while the water-uptake capacity increased from 48 ± 4% for plain κ-carrageenan to 150 ± 5% for 1:2 κ-carrageenan/starch blends. The amylase enzyme showed an effective ability to degrade both the plain κ-carrageenan and κ-carrageenan/starch membranes, and release glucose units for up to 236 and 563, respectively. According to these results, these blends could be effectively used in making safe and biodegradable molded toys with superior water-absorbing capabilities

Data_Sheet_1_Environment predicts seagrass genotype, phenotype, and associated biodiversity in a temperate ecosystem.pdf

Coastal vegetative ecosystems are among the most threatened in the world, facing multiple anthropogenic stressors. A good example of this is seagrass, which supports carbon capture, coastal stabilization, and biodiversity, but is declining globally at an alarming rate. To understand the causes and consequences of changes to these ecosystems, we need to determine the linkages between different biotic and abiotic components. We used data on the seagrass, Zostera marina, collected by citizen scientists across 300 km of the south coast of the United Kingdom as a case study. We assembled data on seagrass genotype, phenotype, infauna, and associated bathymetry, light, sea surface temperature, and wave and current energy to test hypotheses on the distribution and diversity of this temperate sub-tidal ecosystem. We found spatial structure in population genetics, evident through local assortment of genotypes and isolation by distance across a broader geographic scale. By integrating our molecular data with information on seagrass phenotype and infauna, we demonstrate that these ecosystem components are primarily linked indirectly through the effects of shared environmental factors. It is unusual to examine genotypic, phenotypic, and environmental data in a single study, but this approach can inform both conservation and restoration of seagrass, as well as giving new insights into a widespread and important ecosystem.</p

Silicon nanoparticles alleviate cadmium toxicity in rice (Oryza sativa L.) by modulating the nutritional profile and triggering stress-responsive genetic mechanisms

This study investigated the physiological and molecular responses of rice genotype ‘9311’ to Cd stress and the mitigating effects of silicon oxide nanoparticles (SiO NPs). Cd exposure severely hindered plant growth, chlorophyll content, photosynthesis, and Cd accumulation. However, SiO NPs supplementation, particularly the SiONP100 treatment, significantly alleviated Cd-induced toxicity, mitigating the adverse effects on plant growth while maintaining chlorophyll content and photosynthetic attributes. The SiONP100 treatment also reduced Cd accumulation, indicating a preference for Si uptake in genotype 9311. Complex interactions among Cd, Si, Mg, Ca, and K were uncovered, with fluctuations in MDA and H2O2 contents. Distinct morphological changes in stomatal aperture and mesophyll cell structures were observed, including changes in starch granules, grana thylakoids, and osmophilic plastoglobuli. Moreover, following SiONP100 supplementation, genotype 9311 increased peroxidase, superoxide dismutase, and catalase activities by 56%, 44%, and 53% in shoots and 62%, 49%, and 65% in roots, respectively, indicating a robust defense mechanism against Cd stress. Notably, OsNramp5, OsHMA3, OsSOD-Cu/Zn, OsCATA, OsCATB, and OsAPX1 showed significant expression after SiO NPs treatment, suggesting potential Cd translocation within rice tissues. Overall, SiO NPs supplementation holds promise for enhancing Cd tolerance in rice plants while maintaining essential physiological functions