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381.
Perivaldo de Carvalho Leandro Ferreira Domiciano Mircia Angele Mombach Hemython Luis Bandeira do Nascimento Luciano da Silva Cabral Lynn E. Sollenberger Dalton Henrique Pereira Bruno Carneiro Pedreira 《Grass and Forage Science》2019,74(4):650-660
To meet the global demand for animal protein, sustainable intensification of existing livestock systems may be possible, especially through integration of livestock with crops or forestry. Thus, our objective was to compare forage production and animal performance in grass monoculture and integrated systems in the Brazilian Amazon biome. The four systems were (a) livestock (L) with Marandu palisadegrass {Brachiaria brizantha (Hochst. ex A. Rich.) R. D. Webster} as monoculture, (b) palisadegrass pastures integrated with eucalyptus trees (Eucalyptus urograndis; hybrid of Eucalyptus grandis W. Hill ex Maiden and Eucalyptus urophylla S. T. Blake) arranged in three‐row groves with groves spaced 30 m apart (livestock–forestry; LF), (c) palisadegrass after two years of crops (crop–livestock; CL) and (d) palisadegrass after two years of crops with single rows of eucalyptus trees spaced 37 m apart (crop–livestock–forestry; CLF). From July 2016 to July 2017, all experimental units were continuously stocked using a variable stocking rate. Greater herbage accumulation (HA) occurred in CL and CLF in comparison with L and LF (21,310, 24,050, 19,500 and 18,890 kg DM/ha respectively). The gain per hectare of L, LF and CL (average of 932 kg ha–1) was less than CLF (1,190 kg ha–1). Average daily gain was similar among systems (0.69 kg/day). We conclude that integrated systems can support similar (LF or CL) or greater (CLF) levels of animal production than palisadegrass monocultures while increasing diversity of outputs, thereby providing a greater range of viable systems for livestock production in the Brazilian Amazon biome. 相似文献
382.
Chemical characterization of the essential oil from patchouli accessions harvested over four seasons
Arie Fitzgerald Blank Tricia Cavalcanti Pergentino Sant’anaPriscilla Santana Santos Maria Fatima Arrigoni-BlankAna Paula do Nascimento Prata Hugo Cesar Ramos JesusPericles Barreto Alves 《Industrial Crops and Products》2011,34(1):831-837
The genus Pogostemon of the Lamiaceae family includes several species known for their medicinal and aromatic properties. The species P. cablin is especially notable because the essential oil extracted from its leaves is internationally important and valuable, principally for the perfume and cosmetic industries. Because multiple factors can affect the chemical composition of the essential oil, the aim of this work was to evaluate the chemical variations in the essential oils of nine Pogostemon accessions harvested over four seasons. Two Pogostemon accessions (P. heyneanus, but received as P. cablin) and seven P. cablin accessions from different sources were evaluated. The transplants were planted in January 2008, and the harvests were conducted in May, August, and November 2008 and February 2009. The chemical composition of the essential oils was evaluated quantitatively and qualitatively. Patchoulol was the major compound from the four harvests of all of the P. cablin accessions. The principal compound from the accessions POG-001 and POG-006 was β-pinene. Two clusters were detected by multivariate analyses of the four harvests. Cluster I was formed by the accessions POG-001 and POG-006 (P. heyneanus), and Cluster II was formed by the accessions of P. cablin (POG-002, POG-014, POG-015, POG-016, POG-019, POG-021, and POG-022). 相似文献
383.
Ingrid Silva Barberino do Nascimento Jane Sélia dos Reis Coimbra João Paulo Martins Luis Henrique Mendes da Silva Renata Cristina Ferreira Bonomo Mônica Ribeiro Pirozzi Aline Cinquini 《Journal of Cereal Science》2010
The partitioning behavior of the glutenin proteins was evaluated in aqueous two-phase systems (ATPSs) formed by sulfate salts (lithium or sodium) and poly(ethylene glycol) (PEG) with average molar mass of 1500 g mol−1 or 4000 g mol−1. The partition coefficients for the glutenin proteins in each ATPS were investigated as a function of the temperature (278.2 K–318.2 K), tie line length (TLL) and electrolyte nature. In all ATPS, the majority of glutenin proteins spontaneously concentrate in the polymer-rich phase (Kp > 1). The partition coefficient is very dependent on the salt nature and the ATPS formed by PEG + lithium sulfate presents higher Kp values as compared with the ATPS formed PEG + sodium sulfate. An increase of molar mass of polymer promotes a decrease of Kp. Thermodynamic parameters of transfer (ΔtrG, ΔtrH and ΔtrS) were obtained by the application of the Van’t Hoff equation (VHE). The values obtained by VHE indicate that the transfer of glutenin proteins to the polymer-rich phase has an enthalpic origin. 相似文献
384.
R. V. Silva R. D. L. Oliveira K. J. T. Nascimento F. A. Rodrigues 《Plant pathology》2010,59(3):586-593
Coffea arabica cultivars Catuaí 44 and IAPAR 59, susceptible and resistant, respectively, to the root knot nematode Meloidogyne exigua, were grown in pots containing Si‐deficient soil amended with either calcium silicate (+Si) or calcium carbonate (?Si). There was an increase of 152 and 100%, respectively, in Si content of root tissue of cvs Catuaí 44 and IAPAR 59 in the +Si compared to the ?Si treatment, but no significant difference between Si treatments for calcium content. Plants, assessed 150 days after inoculation (d.a.i.) showed that the number of galls (NG) and number of eggs (NE) significantly decreased by 16·8 and 28·1% respectively, for susceptible cv. Catuaí 44 in the presence of Si, whilst both NG and NE were significantly lower for cv. IAPAR 59 compared to the susceptible cultivar regardless of Si treatments. In a separate experiment, biochemical assays were carried out 5 and 10 d.a.i. There was no significant difference between Si treatments and cultivars for concentration of total soluble phenolics. The concentration of lignin‐thioglycolic acid (LTGA) derivatives significantly increased by 11·5% in roots of nematode‐inoculated plants of susceptible cv. Catuaí supplied with Si. In roots of inoculated plants of resistant cv. IAPAR 59, the increase was 23 and 10%, respectively, for treatments with and without silicon. Peroxidase (POX), polyphenoloxidase (PPO) and phenylalanine ammonia lyase (PAL) activities significantly increased in roots of inoculated plants compared with roots of non‐inoculated plants, regardless of cultivar or Si treatment. In +Si treatments at 10 d.a.i., POX activity in roots of nematode‐inoculated plants of cvs Catuaí 44 and IAPAR 59 increased by 39·9 and 31·3%, respectively; PPO increased by 54·9 and 56·1%; and PAL activity was also higher at 26·6 and 62·9%. It was concluded that supplying Si to coffee plants increases root resistance against M. exigua by decreasing its reproductive capacity. 相似文献
385.
AE Jackson 《Australian veterinary journal》2017,95(7):221-222
386.
AE Jackson 《Australian veterinary journal》2017,95(8):263-264
387.
388.
389.
José Aldo Teixeira da Silva Erika Valente de Medeiros Jéssica Morais da Silva Dyana de A. Tenório Keila Aparecida Moreira Talita Camila Evaristo da Silva Nascimento Cristina Souza-Motta 《Phytoparasitica》2017,45(2):219-225
Trichoderma spp. are used as antagonists against different pathogens. Despite many possibilities of using Trichoderma as an antagonist, there are gaps in the knowledge of the interaction between Trichoderma, cassava and Scytalidium lignicola. This fungus causes cassava black root rot and is an inhabitant of the soil, so it is difficult to control. Antagonists may contribute to the possible induction of resistance of plants because, when exposed to such pathosystems, plants respond by producing antioxidative enzymes. The test for potential inhibition of growth of S. lignicola CMM 1098 in vitro was performed in potato-dextrose-agar with two Trichoderma strains T. harzianum URM3086 and T. aureoviride URM 5158. We evaluated the effect of the two selected Trichoderma to reduce the severity of cassava black root rot and shoots. Subsequently, the production of enzymes (ascorbate peroxidase, catalase, peroxidase and polyphenol oxidase) was evaluated in cassava plants. All two Trichoderma strains show an inhibition of the growth of S. lignicola CMM 1098. The most efficient was T. harzianum URM 3086, with 80.78% of mycelial growth inhibition. T. aureoviride URM 5158 was considered the best chitinase producer. All treatments were effective in reducing severity, especially treatments using Trichoderma. Cassava plants treated with T. aureoviride URM 5158 had the highest enzyme activity, especially peroxidase and ascorbate peroxidase. Trichoderma harzianum URM3086 and Trichoderma aureoviride URM 5158 were effective in reducing the severity of cassava black root rot caused by S. lignicola CMM 1098. 相似文献
390.
Alice Maria Nascimento de Araújo Lêda Rita D’Antonino. Faroni José Vargas de Oliveira Daniela Maria do Amaral Ferraz Navarro Douglas Rafael e Silva Barbosa Mariana Oliveira Breda Solange Maria de França 《Journal of pest science》2017,90(2):589-600
The present study aimed to assess the lethal and sublethal responses of five populations of S. zeamais to the essential oils of Ocimum basilicum and Piper hispidinervum, through toxicity, locomotor behavior (flight and walking activities) and physiological (respiration rate and body mass) evaluations. The populations of S. zeamais were obtained from Machado—MG, Paracatu—MG, Piracicaba—SP, Recife—PE and Tunápolis—SC. To estimate the LC50 of each oil for each population, fumigation tests were performed. The population from Recife exhibited the lowest instantaneous rate of increase (ri) as well the lowest consumption of grain mass. However, Piracicaba was considered the susceptibility pattern, presenting the lowest LC50 for both essential oils, no statistical difference was observed among populations or treatments in the flight activity bioassays. The essential oils effect on walking activity and respiration rates varied among populations. The population from Recife presented the highest walked distance and walk speed, with the lowest resting time and number of stops, as well as the lowest respiration rate and body mass. The present study highlights the importance of the study on population responses, as the five populations of S. zeamais exhibited different patterns of toxic and behavioral effects when subjected to the essential oils of P. hispidinervum and O. basilicum. 相似文献