Integrated rice–crayfish (Oryza sativa–Procambarus clarkii) co-culture (RC) systems have gained prominence due to their economic benefits and ecological sustainability; however, the interactions between soil properties and microbial communities in such systems remain poorly understood. This study evaluated the effects of the RC systems on soil physicochemical characteristics and microbial dynamics in paddy fields of southern Henan Province, China, over the 2023 growing season and subsequent fallow period. Using a randomized complete design, rice monoculture (RM, as the control) and RC treatments were compared across replicated plots. Soil and water samples were collected post-harvest and pre-transplanting to assess soil properties, extracellular enzyme activity, and microbial community structure. Results showed that RC significantly enhanced soil moisture by up to 30.2%, increased soil porosity by 9.6%, and nearly tripled soil organic carbon compared to RM. The RC system consistently elevated nitrogen (N), phosphorus (P), and potassium (K) throughout both the rice growth and fallow stages, indicating improved nutrient availability and retention. Elevated extracellular enzyme activities linked to carbon, N, and P cycling were observed under RC, with enzymatic stoichiometry revealing increased microbial nutrient limitation intensity and a shift toward P limitation. Microbial community composition was significantly altered under RC, showing increased biomass, a higher fungi-to-bacteria ratio, and greater relative abundance of Gram-positive bacteria, reflecting enhanced soil biodiversity and ecosystem resilience. Further analyses using the Mantel test and Random Forest identified extracellular enzyme activities, PLFAs, soil moisture, and bulk density as major factors shaping microbial communities. Redundancy analysis (RDA) confirmed that total potassium (TK), vector length (VL), soil pH, and total nitrogen (TN) were the strongest environmental predictors of microbial variation, jointly explaining 74.57% of the total variation. Our findings indicated that RC improves soil physicochemical conditions and microbial function, thereby supporting sustainable nutrient cycling and offering a promising, environmentally sound strategy for enhancing productivity and soil health in rice-based agro-ecosystems.

Background: Luciocyprinus langsoni is a species belonging to the Cyprinidae family. The objective of this study is to gain a comprehensive understanding of its evolutionary history and genetic characteristics. Methods: The complete mitochondrial genome of L. langsoni was determined using overlapping PCR. A phylogenetic analysis was conducted based on 13 protein-coding genes from 48 species. A population genetic diversity analysis using the COI gene and a selection analysis of 13 protein-coding genes were also performed. Results: The mitogenome is 16,586 base pairs long and consists of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and two control regions. It has a high adenine-thymine (A + T) content. The phylogenetic analysis confirms the placement of L. langsoni within the subfamily Cyprininae. The population genetic diversity analysis reveals low variability in the Hechi Longjiang population. The selection analysis shows that all 13 protein-coding genes have evolved under purifying selection with Ka/Ks ratios below 1. Conclusions: These results enhance our understanding of L. langsoni’s evolutionary history and lay a genetic foundation for future studies in population genetics and phylogenetics.

Freshwater ecosystems are increasingly degraded by Cladophora blooms, prompting a need to understand its reproductive characteristics for effective control. We combined continuous microscopical monitoring and single-factor and orthogonal experiments, to characterize the life history and reproductive and growth response to different nutrients, pH, temperature, and light conditions of a bloom-forming Cladophora sp. A novel mode was observed, in which mature sporangia and gametangia rupture to extrude a pyknotic cytoplasmic mass, inside which zoospores and gametes complete maturation and release. The peak zoospore production occurred in Aquatic No. 6 medium at pH 5, 35 °C, and 54 µmol m⁻² s⁻¹, whereas maximum gamete release was recorded in Knop medium at pH 4, 30 °C, and the same irradiance, with temperature being the principal driver for zoospores and nutrient regime for gametes. Growth trials further revealed that low-N and -P conditions sustain growth, whereas nutrient-rich conditions favor reproduction. In addition, pH 4–5, 35 °C, and 54 µmol m⁻² s⁻¹ conditions favored propagule formation, while pH 7–8, 25 °C, and 81 µmol m⁻² s⁻¹ maximized biomass. These findings provide a basis for predicting Cladophora bloom dynamics and offer references for sustainable management of Cladophora in freshwater ecosystems.

Cladophora-dominated filamentous algal blooms constitute a growing threat to aquatic ecosystem stability and aquaculture operations. This study systematically evaluated the algicidal efficacy of sodium hypochlorite (NaClO), both individually and in combination with an organosilicone adjuvant, against Cladophora sp., with particular focus on induced oxidative damage mechanisms. Results demonstrated that NaClO exhibited a dose- and time-dependent inhibitory effect, achieving ≥90% inhibition at 1.20 mmol L⁻¹ within 48 h and >99% by 120 h, significantly surpassing the efficacy of lower concentrations (0.40 mmol L⁻¹) (p < 0.05). Physiological assessment revealed that 1.20 mmol L⁻¹ NaClO significantly suppressed total antioxidant capacity (T-AOC) after 96 h (p < 0.05). Notably, synergistic enhancement was observed with adjuvant co-application: at 0.40 mmol L⁻¹ NaClO, superoxide dismutase (SOD) activity reached its minimum with 0.33 ppm organosilicone adjuvant, showing significant reduction compared to higher adjuvant concentrations (p < 0.05). Furthermore, combinations of 0.80 and 1.20 mmol L⁻¹ with organosilicone adjuvant consistently maintained inhibition rates ≥ 94% across all sampling intervals, achieving control efficacy equivalent to 2.00 and 2.40 mmol L⁻¹ NaClO alone within 48 h. These findings demonstrate that NaClO supplemented with low-dose organosilicone adjuvant constitutes a promising and efficient strategy for mitigating Cladophora blooms.

Background/Objectives: The monotypic genus Araiocypris is currently classified in Xenocyprididae, yet its familial placement has long been controversial and lacks sufficient molecular phylogenetic support. Mitogenomic resources for the family Tanichthyidae remain limited, and the phylogenetic relationship between Araiocypris and tanichthyid species remains unexplored. This study was conducted to re-evaluate the taxonomic status of Araiocypris and characterize the mitogenomic evolution of Tanichthyidae. Methods: The complete mitochondrial genomes of Tanichthys huidongensis and Araiocypris batodes were sequenced, assembled and annotated. Comparative mitogenomic analyses were performed across seven Tanichthyidae species. A maximum-likelihood phylogenetic tree was reconstructed using concatenated sequences of 13 protein-coding genes and 2 ribosomal RNA genes to clarify the phylogenetic position of Araiocypris. Results: Based on mitochondrial phylogenomic evidence, phylogenetic reconstruction strongly supports the reassignment of A. batodes from Xenocyprididae to Tanichthyidae, as it nests within the Tanichthyidae clade and forms a sister group with the genus Tanichthys. Genetic divergence analysis confirms the validity of Araiocypris as a distinct genus. Tanichthyidae mitogenomes display highly conserved architecture with the typical vertebrate gene order. All protein-coding genes undergo strong purifying selection, with cox1 showing the slowest evolutionary rate. Conserved structural domains including CSB-F, CSB-E, CSB-D and CSB1–3 were identified in the control region. Conclusions: This study provides solid mitogenomic evidence for the familial reclassification of Araiocypris and systematically reveals the evolutionary patterns of Tanichthyidae mitogenomes, offering an important reference for further taxonomic and phylogenetic studies of Cypriniformes.