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Three male sheep were fed, throughout three experimental periods, with either only forage, only total mixed ration (TMR) or a mixed diet (TMR + forage). The rich-fibre ingredients of each diet were incubated daily in situ for three days and the ruminal pH was measured every 2 h during the last day of each experimental period. Rumen pH decreased at increased proportion of TMR in diet (P < 0.05). The dry matter (DM) degradability of the grass forage was higher (P < 0.05) in animals receiving only forage than in those receiving the mixed diet whereas the DM degradability of the corn silage was higher (P < 0.05) in animals receiving the mixed diet than in those receiving only TMR. The level of microbial adherence in residues of grass forage was higher (P < 0.05) in animals fed with only forage than in those fed with the mixed diet and, the level of microbial adherence in residue of corn silage was higher (P < 0.05) in animals receiving the mixed diet than in those receiving TMR. The carboxymethylcellulase activity in residues of grass forage was higher (P < 0.05) in sheep fed the mixed diet whereas not significant effect of diet type was observed for this variable in residues of corn silage. In conclusion, increased inclusion of TMR in sheep diet showed a negative impact on microbial adherence and forage degradability in situ , an effect mediated by changes in rumen pH which was not compensated by increased fibrolytic activity. [ABSTRACT FROM AUTHOR]

A novel method for detecting pesticide multi‐residue in grass forage (alfalfa and oat) was established based on the one‐step automatic extraction and purification technology of quick, easy, cheap, effective, rugged, and safe combined with ultrahigh‐performance liquid chromatography quadrupole Orbitrap high‐resolution mass spectrometry. The crushed sample was extracted with acetonitrile with 1% acetate, followed by a cleanup step with a primary‐secondary amine, octadecylsilane, and graphitized carbon black. The extraction and purification were carried out using the one‐step automatic pretreatment equipment. The target pesticides were acquired in positive ion electrospray ionization mode and full scan/data dependent secondary scan mode. The calibration curve shows good linearity over the corresponding concentration range, with the coefficient of determination greater than 0.99. The screening detection limits were 0.5–50 μg/kg, and the limit of quantification for the 206 pesticides was set at 1–50 μg/kg. At the spiking levels of one, two, and 10 times of limit of quantification, more than 95% of pesticides had recovery between 70–120%, with a relative standard deviation ≤20%. The method was proved to be simple, rapid, high‐sensitivity, and could be routinely used for the high throughput screening and quantitative analysis of pesticide residues in alfalfa and oat. [ABSTRACT FROM AUTHOR]

Aims: Monitoring rangeland above‐ground net primary production (ANPP) requires information on the variation of radiation use efficiency (RUE). We studied the spatial and temporal variations of RUE of the herbaceous layer (RUEH) in woodlands and shrublands and its association with grazing regime, environmental, and vegetation variables. Location: We worked in the Arid Chaco (Argentina), an ecotone region between the Chaco and Monte phytogeographic provinces. Woody and herbaceous species coexist in variable proportions in relation to a regional precipitation gradient and local edaphic variations. Methods and results: Over eight growing seasons, we estimated RUEH at 12 sites, each with two contrasting grazing regimes (moderate and severe). To do this, we related estimated ANPPH from biomass harvests and APARH (absorbed photosynthetically active radiation of the herbaceous layer) calculated from the MODIS normalized difference vegetation index (NDVI). Then we linked the RUEH with precipitation, physiognomy, soil, and landscape data. Most of the spatial variability of RUEH was accounted for by the grazing regime. Moderately grazed areas had a three times greater RUEH than severely grazed ones (0.507 and 0.180 g MJ−1 respectively). They also exhibited different proportions of herbaceous functional types. Physiognomic characteristics of the woody layer explained a significant proportion of the spatial variation of RUEH not explained by grazing regime. RUEH was between 30 and 150% greater in woodlands than in shrublands depending on whether the sites were under moderate or severe grazing respectively. Conclusion: Grazing regime and woody physiognomy accounted for most of the variation in herbaceous radiation use efficiency. Our results show that RUEH may be predicted with greater accuracy from a combination of vegetation maps and information on grazing regime. Thus, our models could be incorporated into web platforms that provide ANPPH (forage) monitoring services based on satellite data, in order to improve their estimates in woodlands, shrublands and savanna ecosystems. [ABSTRACT FROM AUTHOR]

With the rising interest in digestate use as a fertilizer on permanent cultures, there is a need to examine its effects on food and feed quality. This study is focused on the use of digestate in grassland fertilization and its effects on nutritive value parameters such as mycotoxin contamination (deoxynivalenol, aflatoxin, and T-2 toxin) and nutrient content (crude protein, crude fat, crude fiber, ash, nitrogen-free extract, digestibility of organic matter, acid detergent fiber, and ash-free neutral detergent fiber). The experiment was carried out in the Czech Republic, and the effects of fertilization regime, year, and harvest date (summer and fall cuts) on nutritive value were observed. An effect of the year on DON, AFB1, and T-2 contamination levels was observed. An effect of the harvest or fertilization regime on mycotoxin contamination was not observed. Significant differences were observed in the content of all nutrients, except ash, depending on the year. Differences were found only in the case of ADF levels, depending on the harvest date, as well; however, no differences were found between fertilization regimes. Our findings suggest that digestate does not negatively affect fodder in terms of nutritive value nor safety.

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Tetraploid Brachiaria ruziziensis genotypes which reproduce sexually are essential for the breeding of other species of the Brachiaria genus which reproduce by apomixis. Aiming at studying the available phenotypic and genetic variability in the breeding population of B. ruziziensis, it was estimated the parameters heritability and genetic and phenotypic correlations between the traits associated with flowering, and the traits responsible for forage yield and nutritional quality. Seventeen traits in 1180 individuals from 59 open pollinated families were studied, and the data were analyzed by mixed model methods. Individuals with sparse flowering presented higher breeding values for total dry matter, yield, and total number of panicles per plant than individuals with early or late flowering. Considering breeding population differences on flowering behavior, on individual narrow sense heritability and on genetic correlations between flowering, agronomic quality and nutritional quality traits have to be considered in intrapopulation breeding and in intrapopulational recurrent selection.

Nitrogen and K deficiency are among the most yield limiting factors in Brazilian pastures. The lack of these nutrients can hamper the chlorophyll biosynthesis and N content in plant tissues. A greenhouse experiment was carried out to evaluate the relationship among N and K concentrations, the indirect determination of chlorophyll content (SPAD readings), nitrate reductase activity (RNO3-) in newly expanded leaf lamina (NL) and the dry matter yield for plant tops of Mombaça grass (Panicum maximum Jacq.). A fractionated 5² factorial design was used, with 13 combinations of N and K rates in the nutrient solution. The experimental units were arranged in a randomized block design, with four replications. Plants were harvested twice. The first harvest occurred 36 days after seedling transplanting and the second 29 days after the first. Significance occurred for the interaction between the N and K rates to SPAD readings and to RNO3- assessment taken on the NL during the first growth. Besides, RNO3- and SPAD readings increased only with the NL N concentration, reaching the highest values of both variables up to about 25 g kg-1, but were ratively constant at higher leaf N. Significant relationships either between SPAD readings or RNO3- activity and shoot dry mass weight were also observed. The critical levels of N concentration in the NL were, respectively, 22 and 17g kg-1 in the first and second harvest. Thus, SPAD instrument and RNO3- assessment can be used as complementary tools to evaluate the N status in forage grass.As deficiências de N e K são um dos principais fatores limitantes para a produção das pastagens brasileiras. Essas deficiências podem comprometer a biossíntese de clorofila e o conteúdo de N nos tecidos vegetais. Realizou-se um experimento com o objetivo de avaliar a relação entre as concentrações de N e K, a determinação indireta do teor de clorofila, a atividade da RNO3- nas lâminas das duas folhas recém-expandidas (LR) e a produção de massa de matéria seca da parte aérea do capim-mombaça, cultivado em solução nutritiva. Utilizou-se o esquema fatorial 5² fracionado, com 13 combinações de N e K. As parcelas foram distribuídas em delineamento experimental de blocos casualizados, com quatro repetições. As plantas foram colhidas duas vezes. Ocorreu significância na interação entre as doses de N e K para as leituras SPAD e para a avaliação da RNO3- efetuadas nas LR durante o primeiro crescimento. A atividade da RNO3- e os valores SPAD elevaram-se somente com o aumento da concentração de N nas LR, atingindo um patamar próximo a 25 g kg-1, permanecendo constante acima desta concentração. Observaram-se relações significativas entre as leituras SPAD, a atividade da RNO3-, a concentração de N nas LR e a produção de massa de matéria seca da parte aérea. Os níveis críticos para N nas LR foram de 22 e 17 g kg-1, respectivamente para o primeiro e segundo cortes. As avaliações com o clorofilômetro SPAD e da atividade da RNO3- podem ser utilizadas como ferramentas complementares para monitorar o estado nutricional em N do capim-mombaça.

Timothy ( Phleum pratense L.) is an important forage grass used for pasture, hay and silage in regions with cool and humid growth seasons. Harvesting conditions could reduce its nutritive value, particularly with extended wilting periods. To understand how daytime or night-time wilting influences the nutritive value of timothy, this study investigated the metabolism of non-structural carbohydrates, including fructan and starch, together with total soluble protein and amino acid patterns in timothy plants harvested at two maturity stages (heading and anthesis) and wilted under controlled conditions for 24 h at two temperatures (15°C, 20°C) and two light regimes (darkness, light) by simulating different wilting management practices. Correlation analysis with the whole dataset showed that soluble protein, glucose and starch contents declined in plant tissues concomitantly with water loss, while amino acid, sucrose and fructose contents increased. Transient increase in amino acid content suggests that the decrease in protein content was due to proteolysis during wilting. Sucrose and fructose contents generally increased in plant tissues harvested at anthesis and wilted in light whereas they were unaffected in plants wilted in darkness. Fructan content remained stable. Fructan exohydrolase ( FEH) and soluble acid invertase ( INV) activities were well preserved during the first 12 h of wilting and might facilitate the fermentation process at the beginning of ensiling by supplying fructose from fructans and hexoses from sucrose to the fermentive bacteria. [ABSTRACT FROM AUTHOR]

With the aimed to evaluate the arbuscular mycorrhizal fungi (AMF) (R. intraradices) and FitoMas-E® effect in production of biomass Pennisetum purpureum Sch. cv. Cuba CT-115, this study was carried R. intraradices strain was reproduced in arbuscular mycorrhizal laboratory and plant growth stimulator FitoMas®-E from Research Institute derivatives Sugarcane was uced. Five treatments were used: T1 (Control), T2 [Production (50 kg ha-1 of urea)], T3 (R. intraradices), T4 (FitoMas-E®) and T5 (R. intraradices + Fitomas -E® + 25 kg ha-1 of urea). A design randomized block with five replications was used. Fungal indicators, leaf contents of N, P and K, fresh and dry biomasses and yield in dry biomass were evaluated. Results showed significant differences between treatments in studies. It was found that treatment with R. intraradices and FitoMas-E® + 25 kg ha-1 of urea reached values of 5,7 t ha-1. With these products application, biomass production can be increased. [ABSTRACT FROM AUTHOR]

The objective of our study was to assess the effect of soil application of sulfur in ammonium sulfate and gypsum and of either soil or foliar application of elemental sulfur on yield of grass forage and its qualitative parameters. The effect of various forms of sulfur on the yields of grass forage and its qualitative parameters was explored in the form of a small plot experiment in the Bohemian-Moravian Uplands in 2004-2006 involving the following variants: 1) sulfur unfertilised control; 2) ammonium sulfate; 3) elemental sulfur; 4) gypsum; 5) foliar elemental sulfur. Sulfurous fertilisers and foliar elemental sulfur were applied to the soil in doses of 40 kg and 8 kg S per ha, respectively. Nitrogen applied in ammonium sulfate was added to all the other variants in the form of ammonium nitrate. Application of the fertilisers was repeated at the beginning of each vegetation season. The stand was cut twice in the course of vegetation. In the harvested biomass we assessed the content of sulfur, nitrogenous substances, and net energy of lactation. The effect of various forms of sulfur on the grass biomass yields was not significant in either of the two cuts. Yields increased after sulfur fertilisation only in the 1st cut, especially after the application of sulfate sulfur and gypsum, and/or after foliar application of elemental sulfur. In the individual years the sulfur content in the biomass gradually increased significantly (0.17-0.23-0.29%). In the first year the sulfur content did not reach the critical deficiency limit (0.2%). Sulfur fertilisation increased the S concentration in grass forage in all the fertilised variants; the highest S content was detected in the variant where gypsum was applied (0.27%). No significant correlation was established between the values of water-soluble sulfur in the soil and the sulfur content in grass forage. Sulfur fertilisation had no significant effect on the N/S ratio, but was the highest in the variant not fertilised with sulfur and the lowest in the gypsum variant. The content of nitrogenous substances and net energy of lactation were significantly the highest after fertilisation with elemental sulfur and was related, among others, to the lowest yields of this variant. Sulfurous fertilisers did not significantly affect the exchangeable soil reaction and the highest content of water-soluble sulfur after the 2nd cut was seen in the gypsum-applied variant. [ABSTRACT FROM AUTHOR]

Abstract: This is the second of two papers presenting the data from an experiment on the application of aerobically-digested sewage sludge (AES), anaerobic lagoon septic wastes (ANS), sewage sludge compost and fertilizer to soils for grass forage and feed corn production at two different sites in Nova Scotia. Crop yields, plant tissue and Mehlich-1 extractable soil nutrients were evaluated; 15 elements were analyzed in the plant tissue and 9 elements in the soil extracts. This paper describes the Ca, Mg, S, Fe, Mn, Cu, Zn and B content of the crops and the Mehlich-1 extractable content of the soils. The response to the amendments was not consistent at the two sites with the two different crops. We found that the septic sludge (ANS) produced the highest forage Fe, Cu and Zn levels and was equal to compost in elevating corn stover and forage S and the forage B content. The compost produced the highest forage Ca and corn Zn, the AES produced the highest corn Mn, and fertilizer produced the highest forage Mn. None of the amendments produced excessive levels of the above nutrients; rather, the amendments improved the feed quality of the forage and corn stover. Lastly, it was noted that the Mehlich-1 extract only had a significantly positive correlation with forage Cu content. [Copyright &y& Elsevier]

Abstract: This paper presents the data from two years of experiments concerned with the application of aerobically-digested sewage sludge, anaerobic lagoon septic sludge, sewage sludge compost or fertilizer to soils for grass forage and feed corn (Zea mays L.) production at two different sites 45km from Truro, Nova Scotia. Crop yields, plant tissue and Mehlich-1 extractable soil nutrients were evaluated; 15 elements were analyzed in the plant tissue and nine elements in the soil extracts. This paper describes the results of crop yields, plant N, P and K content and Mehlich-1 extractable P and K. The research demonstrated the fertilizer produced higher yields of grass forage than the sludge and the compost but equivalent to the sludge in corn yields. Forage and corn N, P and K contents, however, varied with treatment, crop and year, while the compost-amended soils were highest in extractable nutrients. Both sludges and the compost, therefore, could be effective sources of N, P and K for crop production. Compared to the conventional fertilizer, the nutrient availability from the organic amendments (especially N and P) was considerably lower than the 50% assumed at the start of the experiment; the sludges however, provided higher nutrient availability than the compost. [Copyright &y& Elsevier]

ABSTRACT This study aimed to verify the efficiency of multivariate analysis in the identification of promising vigor tests for the evaluation of the physiological quality of seed lots of Brachiaria decumbens cv. Basilisk. Seeds of B. decumbens cv. Basilisk were tested for the following parameters: water content, germination, first germination count, cold test, electrical conductivity, seedling growth, seedling dry mass, first count and emergence percentage of seedlings in laboratory substrate, and seedling emergence in the field. The data obtained in each test-all completely randomized experimental designs-were analyzed separately by means of analysis of variance, Scott-Knott’s test, and multivariate analysis. Principal component analysis is efficient to discriminate vigor and seed germination tests capable of identifying the top performance batch in the field. Germination, first germination count, emergence of seedlings in sand, first seedling emergence count in sand, shoot length, and the cold test are promising in the evaluation of the physiological quality of seed lots of B. decumbens cv. Basilisk, providing similar information to that from the emergence of field seedlings.