The subfamily Salicornioideae (Amaranthaceae) comprises taxa with a notoriously complex taxonomy due to limited diagnostic characters, high phenotypic plasticity, and frequent hybridization. This study aims to provide a practical tool for supporting the identification of Salicornioideae taxa in Sardinia (Italy), with a particular focus on seed traits as diagnostic taxonomic characters. Mature seeds from seven taxa belonging to the genera Salicornia, Arthrocaulon, and Halocnemum were collected across Sardinia and examined using a digital microscope. Seed traits, including shape, size ratios, colour, surface ornamentation, and the presence and morphology of hairs, were analysed quantitatively and qualitatively. Morphological data were organized into a character matrix and assessed to identify diagnostic features. A Factor Analysis of Mixed Data (FAMD) was used to evaluate the discriminatory power of quantitative and qualitative seed traits and to support the selection of characters for a seed-based dichotomous identification key. The resulting key enables the discrimination of Sardinian annual and perennial taxa, as well as closely related species and subspecies. The results demonstrate that, within the set of taxa examined, seed traits are consistent and easily observable characteristics that can distinguish Salicornioideae taxa at genus, species, and subspecies levels. Improving taxonomic discrimination of Salicornioideae taxa supports floristic, ecological, and conservation studies of halophytic vegetation in Mediterranean regions.
Salinity limits early rice establishment by imposing osmotic stress, ionic imbalance, and poor early seedling growth. Magnetic-field seed treatment has been explored mainly using static magnetic fields (SMFs), whereas low-intensity pulsed electromagnetic fields (PEMFs) remain less defined as physical seed-treatment inputs under salinity. Here, we directly compared SMF and 10 Hz PEMF under matched low-intensity conditions to determine whether PEMF can function as an effective physical seed treatment in rice. Seeds of Oryza sativa L. cv. Phitsanulok 2 were exposed to SMF (2.0 mT) or PEMF (10 Hz, approximately 2.0 mT peak) using three protocols—1 h before sowing, 10 min daily after sowing, or a combined schedule—followed by germination under 150 mM NaCl. Magnetic exposure had limited effect on final germination percentage, but a single 1 h pre-sowing treatment with either SMF or PEMF significantly increased the germination rate index under salinity. This protocol also improved root length, seedling dry weight, and seedling vigour, whereas repeated daily exposure produced less consistent benefits. Redox analysis showed that PEMF increased H2O2 at 48 h but reduced H2O2 at 96 and 120 h compared with the untreated saline control at the corresponding sampling time. PEMF also produced the clearest increase in extractable DPPH radical-scavenging activity at 120 h. Ion analysis showed that the 1 h pre-sowing treatment improved tissue ion balance, as reflected by lower Na+ accumulation, improved K+ status, and a reduced Na+/K+ concentration ratio, particularly in roots. Overall, this study identifies a timing-specific low-intensity magnetic-treatment window for improving early rice establishment under salinity and positions 10 Hz PEMF as a testable non-chemical physical treatment associated with redox remodeling and improved ion homeostasis.
The use of cattle manure wastewater for microalgae cultivation is beneficial, as it contains nutrients such as N, P, K, Mg, Zn, and Fe. Therefore, different species of algae were isolated and cultivated, and nutrient analyses were conducted, including microalgae Watanabea sp., which resulted in higher biomass production (1.5 g L−1), 36% protein, and 40% carbohydrates, although the ash fraction was only 8%, the lowest. In a TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) analysis, this species was selected from among the isolates because it demonstrated the best performance for use as a biostimulant for chili germination. After that, optimal conditions were established for cultivating Watanabea sp. microalgae in six polypropylene photobioreactors with a capacity of 2.9 L were used and tested at pH values of 7.0, 7.5, 8.0, 8.5, 9.0, and 9.5, at T = 25 °C, under constant light at 850 µE∙m−2∙s−1, and different dilution rates from 0.1 until 0.9%. The highest biomass production was achieved at pH 7.5 and a dilution rate of 0.1%, indicating that slightly alkaline conditions favored biomass accumulation. These conditions were associated with enhanced nitrate and phosphate assimilation. Furthermore, the effect of Watanabea sp. biomass on stimulating the germination of agricultural chili (Capsicum annuum L.) seeds was evaluated. Three methods of application (grounding and ungrounding freeze-lyophilized and fresh biomass) and concentrations of microalgal biomass (0.5, 1.0, and 1.5 g L−1) and a control (distilled water) were used at two temperatures (25 and 35 °C). The microalgae Watanabea sp. grounding freeze-lyophilized and treated chili seeds increased the final germination percentage and slightly earlier with better vigor and root growth at both temperatures. Further studies are needed to evaluate its effects on seedling establishment and field performance.
Increasing demand for eco-friendly biopolymers requires expanding species’ genotype bases through targeted breeding and detailed screening. The amount and quality of mucilage depend on environmental conditions and on genotype. This study aimed to evaluate the influence of nine oil-type flax varieties, seed fractionation (seeds sorted according to their thickness), and cultivation year on the yield of fresh (FLSM) and lyophilised (LLSM) linseed mucilage. Agram and Astella were characterised by low production of FLSM and LLSM. Lola, Agriol, and Raciol had high levels of LLSM and FLSM production. Libra had high production of FLSM and low production of LLSM. A statistically significant difference in the amount of FLSM and LLSM between the small and large seed fractions was not observed. The results confirmed that the growing season influenced the weight of FLSM but not LLSM. However, differences in the growing season were observed between varieties. The results highlight that some morphological traits in linseeds (solidity, small size of seed, and area of seed) can serve as indicators of lyophilised mucilage production. Differences in the morphological structure of the lyophilised mucilage on macro- and microscopic levels were observed. Our study highlights the need for detailed screening of the flax genetic resources, given the enormous potential of linseed mucilage and its properties.
Climatic variability and recurrent drought increasingly threaten rainfed sunflower production in south-eastern Europe, highlighting the need for practical adaptation strategies. This study evaluated the effects of two sowing dates, early sowing on 24 March (SD1) and conventional sowing on 14–15 April (SD2), corresponding to the common sowing practice in the region, on sunflower productivity and seed quality during three consecutive growing seasons (2023–2025) under rainfed no-till conditions in the Dobrogea Region of Romania. A randomized complete block design with three replications was used, while all agronomic practices remained identical except for sowing date. Crop performance was assessed through yield, oil content, plant density, plant height, seed weight per capitulum, thousand-grain weight (TGW), test weight, and seed moisture, and data were analyzed using ANOVA, Student’s t-test, Pearson correlation, and redundancy analysis (RDA). Early sowing resulted in higher mean values than conventional sowing, increasing seed yield by 25.4% (1341.65 vs. 1070.20 kg ha−1), oil content from 44.80% to 45.90%, TGW from 47.39 to 53.96 g, test weight from 37.46 to 41.64 kg hL−1, and seed weight per capitulum from 34.45 to 38.72 g. The magnitude of the sowing-date response varied among growing seasons, highlighting the importance of considering naturally occurring interannual variability when interpreting treatment effects. RDA indicated that precipitation showed the strongest association with variation in agronomic performance. Advancing sowing by approximately three weeks was associated with improved crop performance across the three growing seasons, which were characterized by naturally occurring interannual meteorological variability. These findings provide site- and hybrid-specific evidence to inform sowing-date decisions for rainfed no-till sunflower production.
