Marine microorganisms play a crucial role in biogeochemical cycles, especially in the surface microlayer (SML), which differs from adjacent subsurface waters (SSW). In this study, we sampled the SML and SSW at 20 sites along the western Antarctic Peninsula during the summers of 2015 and 2019, examining microbial, viral and environmental differences. We focused on phototrophic protists, specifically Phaeocystis-like species, known for their high dimethylsulphoniopropionate (DMSP) contents, which can be released through viral lysis. DMSP is a precursor to dimethylsulphide (DMS), a gas influencing Earth’s climate. We hypothesized a significant relationship between Phaeocystis-like abundance and DMSP concentration, with strong interactions with their specific viruses (V4) in the SML. Most biotic variables showed higher mean values in the SML, although these differences often were not statistically significant. DMSP concentrations correlated with Phaeocystis-like species abundance in both layers (R2 = 0.482, P ≤ 0.01; R2 = 0.532, P ≤ 0.01, respectively), whereas V4 abundance significantly correlated with Phaeocystis-like species only in the SML (R2 = 0.572, P ≤ 0.01). These results suggest stronger interactions between viruses and DMSP-rich hosts in the SML, potentially increasing DMS emissions to the atmosphere and impacting climate regulation.

The Southern Ocean remains one of the most data-deficient ocean basins despite its crucial role in global climate regulation. This study uses racing sailboats from the Barcelona World Race (2010/2011 and 2014/2015) and the Vendée Globe Race (2020/2021) as vessels of opportunity to collect sea-surface temperature and salinity measurements, offering a unique dataset for assessing oceanographic variability in this remote region. We conducted an inter-annual analysis of surface temperature and salinity anomalies relative to ARMOR-3D reanalysis and World Ocean Atlas 2023 climatological datasets, identifying regional patterns of change and variability. The results reveal a warming trend and general freshening of the Southern Ocean surface over the last decade, with the highest anomalies observed in the Indian and Atlantic sectors, whereas the Pacific sector showed the lowest anomalies in absolute terms. Notably, El Niño-Southern Oscillation (La Niña) and Southern Annular Mode phases played a significant role in modulating these temperature and salinity anomalies. This study underscores the scientific value of non-research vessels in monitoring climate-driven changes in Antarctic and sub-Antarctic waters, highlighting their potential to complement traditional observation networks in data-sparse regions.

This study evaluated the effects of combining Bacillus species with hydrolysed and inactive Torula yeast on rumen fermentation of tropical forages in vitro. Exp. 1 assessed different combinations of direct-fed microbials (DFM) and hydrolysed/inactive yeast on the ruminal fermentation of Urochloa brizantha hay in a randomised block design (3×3 factorial scheme). Treatments included: 1) Negative control, no DFM inclusion (NC); 2) B. subtilis and B. licheniformis (SL); 3) B. subtilis, B. licheniformis, B. amyloliquefaciens and B. coagulans (SLAC); 4) Hydrolysed Torula yeast (HY); 5) dry inactive Torula yeast (IY); 6) B. subtilis, B. licheniformis and dry inactive Torula yeast (SL+IY); 7) B. subtilis, B. licheniformis and hydrolysed Torula yeast (SL+HY); 8) B. subtilis, B. licheniformis, B. amyloliquefaciens, B. coagulans and dry inactive Torula yeast (SLAC+IY) and 9) B. subtilis, B. licheniformis, B. amyloliquefaciens, B. coagulans and hydrolysed Torula yeast (SLAC+HY). Bacillus and yeast interaction affected the total short-chain fatty acids (SCFA) and SCFA profile. In treatments without Bacillus, IY resulted in higher isovalerate compared to treatments without yeast (NC). The no yeast treatment also had lower isovalerate concentration than other treatments (HY, IY). Exp. 2 and Exp. 3 evaluated NC, SL, SLAC, SL+HY and SLAC+IY plus SLAC+HY in low- and medium-quality forage. For low-quality forage, SLAC+IY + SLAC+HY had the highest NH3-N concentration, while SL+HY yielded the highest total SCFA. In medium-quality forage, SL+HY showed the highest total SCFA. The combination of Bacillus species and HY may enhance total SCFA and NH3-N in the rumen, improving nutrient utilisation in grazing beef cattle.

Spodoptera frugiperda is a notorious pest that has been recorded attacking over 353 crop species worldwide. Excessive insecticide exposure can lead to resistance and has adverse impacts on the environment and beneficial organisms. Long-lasting pest control methods like entomopathogenic fungi may be used to prevent the negative impact of synthetic insecticides. In the current research, effectiveness of Cordyceps fumosorosea was analysed by applying a sub-lethal dose (LC15 = 2.09 × 106 spores mL−1) and a lethal dose (LC50 = 2.17 × 107 spores mL−1) on filial (F0) and first filial (F1) generations of S. frugiperda to estimate both lethal and sub-lethal effects. The LC15 was used to keep a significant proportion of larvae alive to permit determination of sublethal effects on S. frugiperda. After treatment with the LC15 and LC50, S. frugiperda progeny displayed shorter larval duration, lower fecundity, and shorter adult female and male longevities relative to untreated controls. Likewise, the adult pre-oviposition period, total pre-oviposition period, oviposition days (Od), net reproductive rates (Ro), and mean generation times (T) were reduced in fungal-infected groups. Furthermore, activities of key detoxifying enzymes, i.e. acetylcholinesterase (AChE), glutathione S-transferases (GST), and esterases (EST), were also evaluated. Substantial differences of AChE, GST, and EST (24.3, 18.34, and 10.09 µmol/min/mg protein), respectively, were observed at the LC50 in contrast to the LC15 and controls. The current study showed pathogenicity of C. fumosorosea, which negatively affected insect development and changed the activities of detoxifying enzymes, thereby increasing the effectiveness and eco-friendly management of S. frugiperda.

Epidemiological studies have reported an association between the planetary health diet (PHD), diet-related greenhouse gas emissions (GHGEs), and mortality. However, data from individuals from non-Western countries was limited. Therefore, we aimed to examine this association among Japanese individuals using a cross-sectional ecological study of all 47 prefectures in Japan. Prefecture-level data were obtained from government surveys. The dietary amount was estimated based on the weight of food purchased (211 items) from the 2021–2023 Family Income and Expenditure Survey. Adherence to PHD was scored using the EAT-Lancet index (range, 0 [worst] to 42 [best]) and categorised into four groups: ≤ 24 (n = 14, low), 25 (n = 17, medium-low), 26 (n = 10, medium-high), and 27 points (n = 6, high). Diet-related GHGEs were estimated using previously developed GHGE tables for each food item. Mortality data were obtained using the 2022 Vital Statistics. Mortality rate ratio (RR) was calculated using a multivariate Poisson regression model. After adjusting for confounders, compared to the prefecture in the medium-low group of adherence score, those in the low and high groups were associated with a higher mortality RR for all-cause (low group: RR = 1.03 [95% CI (confidence interval) = 1.01–1.05]; high group: RR = 1.03 [95% CI = 1.00–1.07]) and pneumonia. Moreover, although a higher adherence score was inversely associated with GHGE, it was linked to an increased mortality risk from heart disease and stroke. Our findings indicate a reverse J-shaped association between adherence to PHD and mortality.

The spatial competition in the White Sea’s Halichondria panicea sponge was studied through a field experiment assessing growth in isogeneic and allogeneic sponge fragments of equal or different sizes. After 3 months and 1 year in seawater, growth was evaluated using ImageJ software on photographs. Intraspecific competition among allogeneic H. panicea individuals led to a decrease in relative growth, with the size of interacting individuals influencing competitive strategy. Optimal growth occurred when competitors were larger, minimal when sizes were equal, suggesting an alternative competitive strategy in the latter case. Competition between isogeneic individuals of H. panicea was weak or even absent; fusion of isogeneic fragments increased the growth intensity and substrate coverage by the sponge. Analysing the growth directions of sponges, we have found a phenomenon that may be interpreted as an attempt to ‘avoid’ physical contact with a competitor. In the neighbourhood with an allogeneic individual of larger or smaller size, the growth towards the competitor was lower than in other directions, regardless of whether the neighbouring individuals reached contact with each other or not. This may indicate that growth was redirected due to some distant communication mechanisms. The growth of allogeneic and isogeneic explants before contact occurred in a similar manner. Apparently, H. panicea cannot recognize the genetic nature of a competitor at a certain distance.

The use of sodium channel blocker insecticides (SCBIs) has been one of the tools for managing the resistance of fall armyworm Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) to insecticides. In this study, we selected resistant strains of S. frugiperda to the SCBIs indoxacarb (Indoxacarb-R) and metaflumizone (Metaflumizone-R), under laboratory conditions, to evaluate the inheritance of resistance, cross-resistance to insecticides targeting voltage-gated sodium channels, and verify the absence of the F1845Y and V1848I mutations. The LC50 values of the susceptible (SUS) and the Indoxacarb-R strains to indoxacarb were 3.72 and 114.43 µg mL−1 respectively, and for the SUS and the Metaflumizone-R strains to metaflumizone were 4.57 and 3,141.96 µg mL−1, respectively, with resistance ratios of approximately 30-fold to indoxacarb and >600-fold to metaflumizone. The resistance of S. frugiperda to both insecticides was characterised as autosomal, incompletely recessive, and polygenic. Cross-resistance between indoxacarb and metaflumizone was detected. Moreover, Indoxacarb-R and Metaflumizone-R strains showed lower susceptibility to the pyrethroid insecticide lambda-cyhalothrin, possibly due to multiple resistance. The partial sequencing of the S. frugiperda sodium channel gene did not confirm the association of F1845Y and V1848I mutations with S. frugiperda resistance to indoxacarb and metaflumizone. These results will be important for implementing proactive insect resistance management programmes to preserve the lifetime of SCBIs in controlling S. frugiperda.