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Objective: The aim of this project was to evaluate the effect of crude glycerin addition in the diet, milk composition and milk yield in dairy milking cows on different stages of lactation.   Theoretical  framework: It is necessary to balance the supply of protein and energy in the diet of  lactating cows. Within this context, a by-product of the Biodiesel industry, called crude glycerin, is low cost and has a high energy value for ruminants, since its main component is glycerol, which ruminants have the capacity to use as a precursor gluconeogenic (Chung et al., 2007).   Methods: The experiment was performed with Holstein cows (n=18), divided in two groups of treatment: 1) Basal diet without crude glycerin addition, 2) Diet with 10% of crude glycerin addition in the dry matter. Individual milk samples were collected for the analysis of the percentage of Fat, Protein, Lactose, Total Solids and Somatic Cell Count (Cs mL-1), as well as milk production (liters -1 and corrected for 4% fat).   Results and conclusion:  It was concluded that the addition of crude glycerin in the diet had no significant effect on the milk production and composition of cows of the Dutch breed.   Originality/value: The study results have crucial implications for cow nutrition strategies. Implication of the research: The study results have crucial implications for strategies in the Nutrition of the cows. O objetivo deste trabalho foi avaliar o efeito da adição de glicerina bruta na dieta, composição do leite e produção de leite em vacas leiteiras em diferentes fases da lactação. O experimento foi realizado com vacas holandesas (n=18), divididas em dois grupos de tratamento: 1) Dieta basal sem adição de glicerina bruta, 2) Dieta com 10% de adição de glicerina bruta na matéria seca. O experimento foi conduzido em 56 dias divididos em quatro períodos de 14 dias. Amostras individuais de leite foram coletadas para análise do percentual de Gordura, Proteína, Lactose, Sólidos Totais e Contagem de Células Somáticas (Cs mL mL-1), bem como produção de leite (litros -1 e corrigido para 4% de gordura). Amostras da dieta dos animais foram enviadas para análise bromatológica. Compilaram-se os dados e avaliou-se o efeito da adição de glicerina bruta na composição do leite e na produção sobre as variáveis e a inter-relação com o tratamento. Concluiu-se que a adição de glicerina bruta na dieta não teve efeito significativo sobre a produção e composição do leite de vacas da raça holandesa.

Different Lolium species, common weeds in cereal fields and fruit orchards in Chile, were reported showing isolated resistance to the acetyl CoA carboxylase (ACCase), acetolactate synthase (ALS) and 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) inhibiting herbicides in the late 1990s. The first case of multiple resistance to these herbicides was Lolium multiflorum found in spring barley in 2007. We hypothesized that other Lolium species may have evolved multiple resistance. In this study, we characterised the multiple resistance to glyphosate, diclofop-methyl and iodosulfuron-methyl-sodium in Lolium rigidum, Lolium perenne and Lolium multiflorum resistant (R) populations from Chile collected in cereal fields. Lolium spp. populations were confirmed by AFLP analysis to be L. rigidum, L. perenne and L. multiflorum. Dose-response assays confirmed multiple resistance to glyphosate, diclofop-methyl and iodosulfuron methyl-sodium in the three species. Enzyme activity assays (ACCase, ALS and EPSPS) suggested that the multiple resistance of the three Lolium spp. was caused by target site mechanisms, except the resistance to iodosulfuron in the R L. perenne population. The target site genes sequencing revealed that the R L. multiflorum population presented the Pro-106-Ser/Ala (EPSPS), Ile-2041-Asn+Asp-2078-Gly (ACCase), and Trp-574-Leu (ALS) mutations; and the R L. rigidum population had the Pro-106-Ser (EPSPS), Ile-1781-Leu+Asp-2078-Gly (ACCase) and Pro-197-Ser/Gln+Trp-574-Leu (ALS) mutations. Alternatively, the R L. perenne population showed only the Asp-2078-Gly (ACCase) mutation, while glyphosate resistance could be due to EPSPS gene amplification (no mutations but high basal enzyme activity), whereas iodosulfuron resistance presumably could involve non-target site resistance (NTSR) mechanisms. These results support that the accumulation of target site mutations confers multiple resistance to the ACCase, ALS and EPSPS inhibitors in L. multiflorum and L. rigidum from Chile, while in L. perenne, both target and NTSR could be present. Multiple resistance to three herbicide groups in three different species of the genus Lolium in South America represents a significant management challenge.

Background The availability of chromosome-scale genome assemblies is fundamentally important to advance genetics and breeding in crops, as well as for evolutionary and comparative genomics. The improvement of long-read sequencing technologies and the advent of optical mapping and chromosome conformation capture technologies in the last few years, significantly promoted the development of chromosome-scale genome assemblies of model plants and crop species. In grasses, chromosome-scale genome assemblies recently became available for cultivated and wild species of the Triticeae subfamily. Development of state-of-the-art genomic resources in species of the Poeae subfamily, which includes important crops like fescues and ryegrasses, is lagging behind the progress in the cereal species. Results Here, we report a new chromosome-scale genome sequence assembly for perennial ryegrass, obtained by combining PacBio long-read sequencing, Illumina short-read polishing, BioNano optical mapping and Hi-C scaffolding. More than 90% of the total genome size of perennial ryegrass (approximately 2.55 Gb) is covered by seven pseudo-chromosomes that show high levels of collinearity to the orthologous chromosomes of Triticeae species. The transposon fraction of perennial ryegrass was found to be relatively low, approximately 35% of the total genome content, which is less than half of the genome repeat content of cultivated cereal species. We predicted 54,629 high-confidence gene models, 10,287 long non-coding RNAs and a total of 8,393 short non-coding RNAs in the perennial ryegrass genome. Conclusions The new reference genome sequence and annotation presented here are valuable resources for comparative genomic studies in grasses, as well as for breeding applications and will expedite the development of productive varieties in perennial ryegrass and related species.

The objective of this paper was to review the reproductive biology, herbicide-resistant (HR) biotypes, pollen-mediated gene flow (PMGF), and potential for transfer of alleles from HR to herbicide-susceptible grass weeds including barnyardgrass, creeping bentgrass, Italian ryegrass, johnsongrass, rigid (annual) ryegrass, and wild oats. The widespread occurrence of HR grass weeds is at least partly due to PMGF, particularly in obligate outcrossing species such as rigid ryegrass. Creeping bentgrass, a wind-pollinated turfgrass species, can efficiently disseminate herbicide resistance alleles via PMGF and movement of seeds and stolons. The genus Agrostis contains about 200 species, many of which are sexually compatible and produce naturally occurring hybrids and hybrids with species in the genus Polypogon. The self-incompatibility, extremely high outcrossing rate, and wind pollination in Italian ryegrass clearly point to PMGF as a major mechanism by which herbicide resistance alleles can spread across agricultural landscapes, resulting in abundant genetic variation within populations and low genetic differentiation among populations. Italian ryegrass can readily hybridize with perennial ryegrass and rigid ryegrass due to their similarity in chromosome numbers (2n = 14), resulting in interspecific gene exchange. Johnsongrass, barnyardgrass, and wild oats are self-pollinated species, so the potential for PMGF is relatively low and limited to short distances; however, seeds can easily shatter upon maturity before crop harvest, leading to wider dispersal. The occurrence of PMGF in reviewed grass weed species, even at a low rate, is greater than that of spontaneous mutations conferring herbicide resistance in weeds and thus can contribute to the spread of herbicide resistance alleles. This review indicates that the transfer of herbicide resistance alleles occurs under field conditions at varying levels depending on the grass weed species. Nomenclature: Barnyardgrass; Echinochloa crus-galli (L.) Beauv.; creeping bentgrass; Agrostis stolonifera L.; Italian ryegrass; Lolium perenne ssp. multiflorum (Lam.) Husnot; johnsongrass; Sorghum halepense (L.) Pers.; perennial ryegrass; Lolium perenne L.; rigid (annual) ryegrass; Lolium rigidum Geud.; sterile oat; Avena sterilis L.; wild oat; Avena fatua L.

Background and aims Low nutrient soil is a major limiting factor for normal growth and high yield of plants. Epichloë endophyte infection has been shown to increase host growth, nutrient uptake and balance. This study was done to determine the impact of Epichloë endophyte on growth, survival and elemental nutrient content of perennial ryegrass ( Lolium perenne ) under low fertility conditions. Methods endophyte-infected and endophyte-free plants of L. perenne were grown without fertilization in a greenhouse environment. Plant survival rate, dry weight of leaves and roots, root metabolic activity and nutrient element (C, N, P, Na, K, Ca, Mg, Cu, Fe, Zn, Mn) contents were determined after 0 d, 45 d, 90 d, 135 d and 180 d. Results The presence of Epichloë endophyte relieved the withering and yellowing of plants in the short term (0 to 90 d). The possible mechanisms by which E. festucae var . lolii infection enhances survival of plants includes improved root growth and metabolic activity (i.e., cellular metabolism), increased biomass production, and increased concentration of many nutrient elements in leaves and roots. The endophyte had positive direct and indirect effects on plants in multiple ways, including: increased organic carbon, total nitrogen, total phosphorus and Mn content in leaves, increased K content in leaves and roots, and improved root growth and activity. Conclusions The presence of endophyte E. festucae var . lolii played a key role in improving the survival of L. perenne plants by increasing root growth and metabolic activity, promoting plant biomass and altering nutrient content.

Cadmium (Cd) and arsenic (As) exist simultaneously in soil environment, which poses a serious threat to the safety of agricultural products and forage production. Four Perennial Ryegrass ( Lolium perenne L.) cultivars with different accumulation characteristics (ʻNicaraguaʼ, ʻVenusʼ, ʻExcellentʼ and ʻMonroʼ) were selected as the material for pot experiment. The coupled responses of key components and related enzyme activities under combined stresses of Cd and As were investigated. key components contents include Non protein sulfhydryl (NPT), glutathione (GSH) and phytochelatins (PCs). The related enzyme includes (superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), γ-glutamylcysteine synthetase (γ-ECS), glutathione synthetase (GSS), phytochelatin synthetases (PCSase) and arsenate reductase (AR). The results showed that Cd contents of perennial ryegrass were higher than those of As contents with TF Cd/As  < 1. Cd and As contents in roots were in the higher proportion than those in shoots. Compared to control, POD activities increased by 2.72 folds under 120 mg kg −1 As treatment. The contents of PCs increased by 5.68 folds under 120 mg kg −1 As treatment. Under combined Cd and As stress, the MDA contents and antioxidant enzyme activities of ʻVenusʼ were higher than those of ʻNicaraguaʼ. ʻNicaraguaʼ, a high accumulation cultivar. Under the combined stresses of Cd and As, the enzyme activities and the key components were significantly correlated ( P  < 0.05) with the contents of Cd and As. The tolerance to Cd and As was improved with increase in GSH and PCs contents and γ-ECS, GSS, PCSase and AR activities. In conclusion, the antioxidant enzyme system and key resistant substances of perennial ryegrass have important and antagonistic effects on Cd and As stresses.

Annual ryegrass toxicity (ARGT) is an often-fatal poisoning of livestock that consume annual ryegrass infected by the bacterium Rathayibacter toxicus. This bacterium is carried into the ryegrass by a nematode, Anguina funesta, and produces toxins within seed galls that develop during the flowering to seed maturity stages of the plant. The actual mechanism of biochemical transformation of healthy seeds to nematode and bacterial gall-infected seeds remains unclear and no clear-cut information is available on what type of volatile organic compounds accumulate in the respective galls. Therefore, to fill this research gap, the present study was designed to analyze the chemical differences among nematode galls (A. funesta), bacterial galls (R. toxicus) and healthy seeds of annual ryegrass (Lolium rigidum) by using direct immersion solid-phase microextraction (DI-SPME) coupled with gas chromatography–mass spectrometry (GC-MS). The method was optimized and validated by testing its linearity, sensitivity, and reproducibility. Fifty-seven compounds were identified from all three sources (nematode galls, bacterial galls and healthy seed), and 48 compounds were found to be present at significantly different (p < 0.05) levels in the three groups. Five volatile organic compounds (hexanedioic acid, bis(2-ethylhexyl) ester), (carbonic acid, but-2-yn-1-yl eicosyl ester), (fumaric acid, 2-ethylhexyl tridec-2-yn-1-yl ester), (oct-3-enoylamide, N-methyl-N-undecyl) and hexacosanoic acid are the most frequent indicators of R. toxicus bacterial infection in ryegrass, whereas the presence of 15-methylnonacosane, 13-methylheptacosane, ethyl hexacosyl ether, heptacosyl acetate and heptacosyl trifluoroacetate indicates A. funesta nematode infestation. Metabolites occurring in both bacterial and nematode galls included batilol (stearyl monoglyceride) and 9-octadecenoic acid (Z)-, tetradecyl ester. Among the chemical functional group, esters, fatty acids, and alcohols together contributed more than 70% in healthy seed, whereas this contribution was 61% and 58% in nematode and bacterial galls, respectively. This study demonstrated that DI-SPME is a valid technique to study differentially expressed metabolites in infected and healthy ryegrass seed and may help provide better understanding of the biochemical interactions between plant and pathogen to aid in management of ARGT.

Background and aims Mine tailings often contain high concentrations of metals that may lead to serious environmental concerns. Phytoremediation by suitable plant species, coupled with organic amendments, represents an intriguing way of improving the quality of mine tailings. Methodology We conducted a glasshouse pot study to assess the impact of biochar derived from wheat straw (BC) and wheat straw (WS) at different application rates (w/w: 0%, 1%, 2%, 5%, 10%) in enhancing physicochemical and biological attributes of iron ore mine tailings. Perennial ryegrass ( Lolium perenne L.) growth and uptake of metals (Co, Cu, Fe, Mn, Zn, Cr, Ni, Pb) and As were assessed. Results The pH (H2O) of iron mine tailings (6.62 with 0% amendment) significantly increased to 8.01 in BC 10% but decreased to 5.33 in WS 10%. However, electrical conductivity, total carbon, total nitrogen and cation exchange capacity increased significantly with application of either amendment. Improvement in physicochemical parameters of tailings by amending with WS was associated with significantly greater plant growth compared with BC amendment. Shoot As and Pb accumulation by perennial ryegrass was low (below detection limit), whereas that of Co, Cu, Fe, Mn, Zn, Cr and Ni increased with an increase in both BC and WS application. Microbial biomass carbon and respiration were enhanced more in the WS than in BC treatments. Conclusion This study suggests wheat straw is a better amendment than biochar for the iron ore mine tailings.

Aims Phosphorus resources have to be managed sustainably and therefore the recycling of P from waste streams is essential. A thermo-chemical recycling process has been developed to produce a P fertilizer from sewage sludge ash (SSA) but its plant availability is unknown. Methods Two SSA products prepared with either Ca[Cl.sub.2] (SSACa) or Mg[Cl.sub.2] (SSAMg) as chemical reactant during the thermal treatment were mixed with three soils previously labeled with [sup.33]P. Reference treatments with water-soluble P added at equal amounts of total P were included. The transfer of P from SSACa and SSAMg to Lolium multiflorum or P pools of sequentially extracted soil-fertilizer incubations were quantified. Results The shoot P uptake from SSAMg was higher than from SSACa. For SSAMg the relative effectiveness compared to a water-soluble P fertilizer was 88 % on an acidic and 71 % on a neutral soil but only 4 % on an alkaline soil. The proportion of P derived from the fertilizer in the plant and in the first two extraction pools of soil-fertilizer incubations were strongly correlated, suggesting that it is sufficient to conduct an incubation study to obtain robust information on plant P availability. Conclusions We conclude that under acidic to neutral conditions SSAMg presents an appropriate alternative to conventional P fertilizers and the dissolution of P from SSAMg seems to be governed by protons and cations in the soil solution. Keywords Sewage sludge ash * [sup.33]P labeling * Recycling fertilizer * Radioisotopes * Italian ryegrass * Sequential extraction