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Future Scenario Projections of Livestock Carrying Status of Grassland Ecosystem in Kazakhstan

As a country dominated by animal husbandry, the livestock carrying status in Kazakhstan has a prolonged impact on grassland degradation and restoration, and thus on the supply of grassland ecosystem services. Here we predict future conditions of livestock carrying status by modeling change in potential forage supply and consumption from 2020 to 2030, using three alternative scenarios following Representative Concentration Pathways, specifically SSP2 (RCP4.5, MESSAGE), SSP1 (RCP2.6, IMAGE) and SSP3 (RCP7.0, AIM), namely BAU, TSS and SSS respectively. Our future scenarios suggested that from 2020 to 2030, the forage consumption in central and southern regions of Kazakhstan is predicted to increase rapidly, while forage supply will decrease in these regions, especially the northern parts. The livestock carrying status in the southern regions tends to be overloaded to different degrees especially under the SSS and BAU scenarios, whereas the other areas hold surplus status. Our study could serve as a scientific basis for enhancing grassland management and achieving the target of the Sustainable Development Goals 2030

Application of Fall Nitrogen Increased Spring Tall Fescue Yield

Late season nitrogen fertilization is a practice that has long been implemented in turfgrass production. This practice involves applying nitrogen from September through December and results in an extended green period in the fall without stimulating excessive shoot growth. The longer green period results in higher levels of carbohydrate reserves and enhanced root growth compared with a spring-summer fertilization program. In addition to these benefits, sods fertilized in late fall have been shown to green up two to six weeks earlier in the spring. Limited research has considered the impact of late fall nitrogen applications on grass growth in hayfields and pastures. The objective of this study was to evaluate the impact of late fall nitrogen fertilization on dry matter production of an established tall fescue stand. In 2020 and 2021, the study was conducted at the UK Research and Extension Center located in Princeton, KY. The experimental design was a random complete block with four replications. In early December 2020 and 2021, 0, 34, 67, and 101 kg ha-1 was applied as ammonium nitrate, ammonium sulfate, and Anuvia SYMTRX 20S. An additional 90 kg ha-1 was applied as urea to all plots the following spring. Plots were harvested on 13-May-2021 and 24-May-2022 using a self-propelled sickle bar type forage harvester equipped with load cells. Averaged across sources, first harvest yields ranged from 3428 to 5675 and 3929 to 5831 kg ha-1 in 2021 and 2022, respectively. Fall applied nitrogen resulted in a linear increase in dry matter yield of 25.0 and 21.2 kg ha-1 in 2021 and 2022, respectively. Nitrogen sources had no impact on dry matter yield (P \u3e 0.05). Plots receiving fall applied nitrogen also initiated growth earlier in the spring

Cytological and Agronomic Evaluation of Interspecific Hybrids Between \u3cem\u3eTrifolium repens\u3c/em\u3e L and \u3cem\u3eT. Occidentale\u3cem\u3e coombe

Trifolium occidentale is a diploid wild relative of T. repens with adaptation to dry, saline coastal habitats. Transfer of drought and salt-tolerant adaptive traits from this potential source of germplasm to T. repens could be valuable if interspecific hybridization can be achieved efficiently. To achieve hybridisation, 4x plants of T. occidentale were generated through colchicine chromosome doubling. Interspecific 4x F1 plants were achieved without embryo rescue. F2 populations and backcross (BC) hybrids to white clover were also efficiently achieved. Although male and female fertility in primary F1 and F2 hybrids were lower than in white clover, they were adequate to produce large amounts of seed from small numbers of inflorescences. Thus, early generation pre-breeding interspecific hybrid populations can be readily developed, opening the way for transfer of traits from T. occidentale to white clover. For effective introgression (backcross) breeding, it is also essential that interspecific chromosome pairing and recombination occur. In this study, it was apparent that chromosome pairing was occurring not only between T. occidentale and T. repens subgenomes, but also between the ancestral subgenomes of T. repens. Thus, interspecific hybridization has the potential for major genome recombination and opens the way for introgression of traits from T. occidentale into white clover. Eighty hybrid families, comprising backcross one (BC1), backcross two (BC2) and their inter-crosses, were evaluated in the field and compared with eight commercial T. repens cultivars and nine T. repens x T. uniflorum backcrosses under three natural summer droughts. Some hybrid families performed as well as, or better than, elite cultivars and had superior recovery after drought periods. Selected plants were inter-crossed to further reshuffle the inter-specific chromosomes for introgression

Human papilloma virus type 16 seroprevalence among men living with HIV

Objectives: Individuals living with HIV are at a higher risk for developing human papillomavirus-driven oropharyngeal cancer (HPV-OPC). There are no methods for early detection; however, HPV16 E6 antibodies have been identified as a promising early marker. The objective of this study was to evaluate seroprevalence and predictors of HPV16 E6 seropositivity among men living with HIV. Methods:2,334 men aged 40+ living with HIV with blood specimens banked within the Tennessee Center for AIDS Research (TN-CFAR) biorepository were evaluated using HPV multiplex serology. Seroprevalence of HPV16 antibodies was calculated for all HPV16 proteins analyzed (L1, E1, E2, E4, E6, E7). Based on mean fluorescence intensity (MFI), HPV16 E6 seroprevalence was further evaluated by moderate (MFI ≥484 and Results: Seroreactivity against HPV16 L1 was most common (23.01%), followed by HPV16 E4 (10.58%), HPV16 E6 (5.79%), HPV16 E2 (5.01%), and HPV16 E7 (4.11%). Of the 135 men with HPV16 E6 antibodies, 55 (2.36%) had moderate antibody levels and 80 (3.43%) had high antibody levels. HPV16 E6 seropositive men were more likely to be seroreactive against at least one other HPV16 protein (OR: 2.44 [95% CI: 1.72-3.47]; PPP Conclusions: This is the largest study to date to evaluate HPV antibodies among men living with HIV and the only centered in the southeastern region – an area with the highest incidence of HPV-OPC in the nation. HPV16 E6 seroprevalence was elevated compared to prior studies in both in the general and HIV populations, likely reflecting the high incidence of HPV-OPC in this region

Canopy Characteristics and Growth Rate of Bahiagrass Monoculture and Mixtures with Rhizoma Peanut

Understanding relationships among canopy light interception (LI), canopy height and structure, and leaf area index (LAI) informs management decisions and can improve efficiency of forage-livestock systems. In a long-term experiment in Florida, USA, we assessed the LI, LAI and sward height relationships of rhizoma peanut (Arachis glabrata Benth., RP)-bahiagrass (Paspalum notatum Flügge) mixed swards compared with bahiagrass monoculture to determine whether changes in canopy structure affect herbage accumulation (HA) rate due to changes in radiation use. Treatments were arranged in a semi-factorial, split-plot design (r=4). Bahiagrass monoculture and bahiagrass-RP mixtures were whole-plot treatments. Sub-plot treatments were an undefoliated control, forage clipped to 5 cm when LAI \u3e 3, and forage clipped to 5 cm when LAI \u3e 3 and fertilized immediately after with 20 kg N ha-1. During 2021, LI, LAI and canopy height were measured weekly using a LiCOR LAI-2200 and a rising plate meter (platemeters g1000), respectively. The proportion of bahiagrass and RP in total herbage mass was determined for each treatment in July 2021. Herbage accumulation rate was calculated as HA during the regrowth period divided by days between clipping events. The relationship of LI and LAI was assessed with a negative exponential model. Relationships of cumulative LAI and sward height and days after clipping were determined using regression analysis. Incorporating RP into bahiagrass increased LI at shorter sward height compared with bahiagrass monoculture due to a greater LAI mm-1 of sward height (190-220 vs. 150-160 mm). Fertilized mixtures achieved LAI95 faster than bahiagrass monoculture, however, changes in mixture canopy structure did not result in greater radiation-use efficiency compared with fertilized bahiagrass monoculture. Herbage accumulation rate decreased for mixtures containing more than 30% RP. Application of this information can improve the efficiency of grazing systems and maximize HA of bahiagrass-RP mixtures, either under rotational or continuous stocking

Systemic signaling in plants: Role of cuticle, salicylic acid, RNA, and vitamins

Systemic acquired resistance (SAR) is a form of broad-spectrum resistance induced in response to local infection that protects uninfected parts against subsequent secondary infections. Several diverse chemical signals contributing to SAR have been isolated and characterized, including glycerol-3-phosphate (G3P) and pipecolic acid (Pip), both of which play an important role in human and plant disease physiologies. In addition to these, salicylic acid (SA) also regulates SAR and normal transport of SA and G3P is required for de novo biosynthesis of Pip in the distal leaves. Pip is catabolized via multiple pathways, and this in turn regulates vitamin homeostasis. A normal SAR also requires a normal cuticle, which in turn regulates water potential and thereby apoplastic transport of SA. Both SA and G3P regulate the stability of trans-acting small interfering RNA (tasi-RNA), which function as an early mobile signal in SAR. Conversely, knock-out mutations in tasi�RNA or RNA silencing components required for tasi-RNA biogenesis compromise SAR without altering levels of SA or G3P. Together, these results highlight a novel relationship between plant cuticle, SA, G3P, Pip vitamins and RNA-mediated signaling in SAR

Regeneration of Somatic Hybrids Between Festuca Arundinacea var. glacescens and Lolium multiflorum LAM.

Protoplasts derived from ten suspension cultures of tetraploid Festuca arundinacea var. glaucescens (2n = 4x = 28) and diploid Lolium multiflorum Lam. (2n = 2x =14) were fused to produce somatic hybrids. Regenerated green plants in three fusion combinations were identified as somatic hybrids because they showed characters that were peculiar to both Festuca arundinacea var. glaucescens (hairs on auricle) and Lolium multiflorum Lam. (root-fluorescence). Moreover, the hybrids also had a chromosome number of about forty two

Evaluating Cultivars of Subterranean Clover in Monoculture or with Perennial Ryegrass

Over four years, sowing perennial ryegrass (Lolium perenne) with a range of subterranean clover (“sub clover”, Trifolium subterraneum) cultivars was found to reduce the yield of clover per se by 31% and increase pasture yield by 11%. For one high-producing experimental variety, the presence of grass did not reduce clover yield (P\u3c0.001). Clover yield in monoculture plots was poorly correlated with that measured in mixed swards (r = 0.44), but clover yield (± grass) was correlated with total herbage yield (r = 0.94). Clover seed yield was not reduced by the presence of grass. However, in year 2 - but not in the establishment year - grass reduced seed weight. Irrespective of grass treatment, the new late maturing cultivar, Leura outyielded the other commercial cultivars (P\u3c0.05). Enfield and Enfield x Daliak crosses set the most seed and regenerated with a greater density than other cultivars (P\u3c0.05) - apart from Leura. It was concluded that the winter-active, late maturing cultivar, Leura, will compete most successfully with perennial ryegrass

Effects of Intrinsic Tannins on Metabolome During Sainfoin Ensiling

Condensed tannins (CT) from sainfoin have a high capacity to inhibit proteolysis. The objective of the present study was to investigated the effects of CT (following supplementation of deactivated CT with polyethylene glycol [PEG]) on metabolome during sainfoin ensiling. As results, in total, 510 metabolites were identified after 60 d of sainfoin ensiling, with 33 metabolites were annotated in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Among those metabolites, phospholipids were the most abundant (72.7% of total 33 metabolites). In addition, 10 up-regulated and 23 down-regulated metabolites, respectively, were identified in the PEG treated group when compared with the control group, after 60 d of ensiling (p \u3c 0.05). Pediococcus (correlated with 20 metabolites, R2 \u3e 0.88, p \u3c 0.05) and Lactobacillus (correlated with 16 metabolites, R2 \u3e 0.88, p \u3c 0.05) were the bacteria most correlated with metabolites. The results suggested antagonistic effects between Lactobacillus and Pediococcus during ensiling. The proteolysis decreased partly due to CT inhibiting Pediococcus activity during ensiling, with Pediococcus being significantly and positively correlated with dopamine after 60 d of ensiling (R2=0.8857, p \u3c 0.05)