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Drought is a most prevalent environmental stress affecting the productivity of rainfed wheat and maize in the semiarid Loess Plateau of China. Sustainable agricultural practices such as intercropping are important for enhancing crop performance in terms of better physiological and biochemical characteristics under drought conditions. Enzymatic and non-enzymatic antioxidant enzyme activities are associated with improved abiotic tolerance in crop plants, however, its molecular mechanism remains obscure. A 2-year field study was conducted to evaluate the influence of intercropping treatment viz. wheat mono-crop (WMC), maize mono-crop (MMC), intercropping maize (IM) and wheat (IW) crops, and nitrogen (N) application rates viz. control and full-dose of N (basal application at 150 and 235 kg ha−1 for wheat and maize, respectively) on chlorophyll fluorescence, gas exchange traits, lipid peroxidation, antioxidative properties and expression patterns of six tolerance genes in both crops under rainfed conditions. As compared with their respective monocropping treatments, IW and IM increased the Fo/Fm by 18.35 and 14.33%, PS-11 efficiency by 7.90 and 13.44%, photosynthesis by 14.31 and 23.97%, C-capacity by 32.05 and 12.92%, and stomatal conductance by 41.40 and 89.95% under without- and with-N application, respectively. The reductions in instantaneous- and intrinsic-water use efficiency and MDA content in the range of 8.76–26.30% were recorded for IW and IM treatments compared with WMC and MMC, respectively. Compared with the WMC and MMC, IW and IM also triggered better antioxidant activities under both N rates. Moreover, we also noted that intercropping and N addition regulated the transcript levels of six genes encoding non-enzymatic antioxidants cycle enzymes. The better performance of intercropping treatments i.e., IW and IM were also associated with improved osmolytes accumulation under rainfed conditions. As compared with control, N addition significantly improved the chlorophyll fluorescence, gas exchange traits, lipid peroxidation, and antioxidant enzyme activities under all intercropping treatments. Our results increase our understanding of the physiological, biochemical, and molecular mechanisms of intercropping-induced water stress tolerance in wheat and maize crops. [ABSTRACT FROM AUTHOR]

In dryland farming, maize (Zea mays L.) and peanut (Arachis hypogaea L.) intercropping has been widely practiced to achieve sustainable agriculture goals. However, only a few studies have investigated the effect of reducing nitrogen (N) application on the performance of maize and peanut crops in intercropping system based on rotation of the planting strip. Therefore, a field study was conducted from 2018 to 2020 in Yangling, China, where the treatments comprised peanut monoculture, maize monoculture, maize–peanut intercropping, maize–peanut rotational intercropping, and maize N reduction based on the rotational intercropping system. The N accumulation and yield in maize increased after intercropping, while the N accumulation, yield and N fixation capacity of peanut decreased than other treatments. In addition, soil residual N, ammonia volatilization, N leaching, and N 2 O emissions of maize–peanut intercropping significantly decreased than maize monoculture. The rotation of planting strips in maize–peanut intercropping had increased the land equivalent ratio by 3.06 % and 9.39 % and N recovery efficiency by 15.45 % and 27.37 % in the second and third years of planting, as well as alleviated the continuous cropping barrier for peanuts. N reduction does not affect N fixation capacity and yield of peanut and reduces ammonia volatilization and N leaching from farmland, although it does influence maize yield. The optimal cropping system was a 20 % N reduction in maize planting strip under rotational intercropping because N accumulation and the farmland productivity were not affected significantly, while the N losses to the environment also decreased by an average of 44.17 % and 14.87 % compared with traditional intercropping and monoculture in the second and third years of planting. These results are useful for optimizing cropping systems to promote sustainable development in dryland regions and mitigate N pollution. • Maize-peanut intercropping in dry farming can reduce apparent N loss. • The intercropping N advantage tended to decrease with prolonged experiment duration. • Rotation of planting strips increase the N accumulation and N fixation in peanut. • The marginal benefits were affected by the N application rate. • 20 % N reduction in maize can reduce N-stress of farmland without affecting yield. [ABSTRACT FROM AUTHOR]

With the intensification of crop production pressure and the urgency of mitigating greenhouse gas emissions, semi-arid regions have increasingly become one of the key areas of research. However, due to the relatively low indigenous soil organic matter (SOM), it is worth pondering whether the long-term introduction of cropland management measures will affect the soil organic carbon (SOC), greenhouse gases (GHGs) and global warming potential (GWP) in the semi-arid areas. This long-term fertilization experiment was conducted for four years during 2017–2021 to assess fertilization impacts on net global warming potential (NGWP) including estimation of SOC change, N 2 O and CH 4 emissions and indirect emissions (IE), and the greenhouse gas intensity (GHGI) on the winter wheat in a semi-arid region of China. The treatments included five levels of N application including non-N-fertilized control (N0), 75 kg N·ha−1 (N75), 150 kg N·ha−1 (N150), 225 kg N·ha−1 (N225) and a traditional N application rate, 300 kg N·ha−1 (N300). In comparison with N300, N225 caused a significant increase in SOC content and SOC sequestration rates and reduced the N 2 O and CH 4 emissions and N 2 O emission factor (EF N2O) followed by N150, N75 and N0. Indirect emissions from farm inputs were highest in the N300 treatment due to excessive N application. The higher grain yield, during all study years, was recorded in N225 treatment and there was no significant difference between N150 and N300 treatments. However, the lowest grain yield was recorded from N0, followed by N75. The lowest mean NGWP and net greenhouse gas intensity (NGHGI) were recorded from the N150 and N225 treatments than all other treatments. The results of this study suggested that N application at 150–225 kg·ha−1 is an effective method to enhance SOC sequestration and grain yield and to reduce the GHGI. • Net ecosystem carbon and greenhouse gas budgets are evaluated for four years. • Soil organic carbon (SOC) content and N 2 O emissions were increased and CH 4 absorption decreased with increasing N rates. • Compared with N300, N150 and N225 has the highest NGWP and GHG emissions. • N150 and N225 treatments can record maximum SOC sequestration than low and higher N rates. [ABSTRACT FROM AUTHOR]

Genus Thermus is the main focus of researcher among the thermophiles. Members of this genus are the inhabitants of both natural and artificial thermal environments. We performed phylogenomic analyses and comparative genomic studies to unravel the genomic diversity among the strains belonging to the genus Thermus in geographically different thermal springs. Sixteen Thermus strains were isolated and sequenced from hot springs, Qucai hot springs in Tibet and Tengchong hot springs in Yunnan, China. 16S rRNA gene based phylogeny and phylogenomic analyses based on concatenated set of 971 Orthologous Protein Families (supermatrix and gene content methods) revealed a mixed distribution of the Thermus strains. Whole genome based phylogenetic analysis showed, all 16 Thermus strains belong to five species; Thermus oshimai (YIM QC-2-109, YIM 1640, YIM 1627, 77359, 77923, 77838), Thermus antranikianii (YIM 73052, 77412, 77311, 71206), Thermus brokianus (YIM 73518, 71318, 72351), Thermus hydrothermalis (YIM 730264 and 77927) and one potential novel species 77420 forming clade with Thermus thalpophilus SYSU G00506 T . Although the genomes of different strains of Thermus of same species were highly similar in their metabolic pathways, but subtle differences were found. CRISPR loci were detected through genome-wide screening, which showed that Thermus isolates from two different thermal locations had well developed defense system against viruses and adopt similar strategy for survival. Additionally, comparative genome analysis screened competence loci across all the Thermus genomes which could be helpful to acquire DNA from environment. In the present study it was found that Thermus isolates use two mechanism of incomplete denitrification pathway, some Thermus strains produces nitric oxide while others nitrious oxide (dinitrogen oxide), which show the heterotrophic lifestyle of Thermus genus. All isolated organisms encoded complete pathways for glycolysis, tricarboxylic acid and pentose phosphate. Calvin Benson Bassham cycle genes were identified in genomes of T. oshimai and T. antranikianii strains, while genomes of all T. brokianus strains and organism 77420 were lacking. Arsenic, cadmium and cobalt-zinc-cadmium resistant genes were detected in genomes of all sequenced Thermus strains. Strains 77,420, 77,311, 73,518, 77,412 and 72,351 genomes were found harboring genes for siderophores production. Sox gene clusters were identified in all sequenced genomes, except strain YIM 730264, suggesting a mode of chemolithotrophy. Through the comparative genomic analysis, we also identified 77420 as the genome type species and its validity as novel organism was confirmed by whole genome sequences comparison. Although isolate 77420 had 99.0% 16S rRNA gene sequence similarity with T. thalpophilus SYSU G00506 T but based on ANI 95.86% (Jspecies) and digital DDH 68.80% (GGDC) values differentiate it as a potential novel species. Similarly, in the phylogenomic tree, the novel isolate 77,420 forming a separate branch with their closest reference type strain T. thalpophilus SYSU G00506 T ., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

We describe the seroprevalence of severe fever with thrombocytopenia syndrome virus (SFTSV) and the association of antibody occurrence with location, sex, and age among the human population in Pakistan. Our results indicate substantial activity of SFTSV and SFTSV-related viruses in this country.