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1.
Environ Manage ; 53(2): 266-73, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24158269

RESUMO

Proper grazing management practices can generate corresponding compensatory effects on plant community production, which may reduce inter-annual variability of productivity in some grassland ecosystems. However, it remains unclear how grazing influences plant community attributes and the variability of standing crop. We examined the effects of sheep grazing at four stocking rate treatments [control, 0 sheep ha(-1) month(-1); light (LG), 0.15 sheep ha(-1 )month(-1); moderate (MG), 0.30 sheep ha(-1) month(-1); and heavy (HG), 0.45 sheep ha(-1) month(-1)] on standing crop at the community level and partitioned by species and functional groups, in the desert steppe of Inner Mongolia, China. The treatments were arranged in a completely randomized block design over a 9-year period. Standing crop was measured every August from 2004 to 2012. Peak standing crop decreased (P < 0.05) with increasing stocking rate; peak standing crop in the HG treatment decreased 40 % compared to the control. May-July precipitation explained at least 76 % of the variation in peak standing crop. MG and HG treatments resulted in a decrease (P < 0.05) in shrubs, semi-shrubs, and perennials forbs, and an increase (P < 0.05) in perennial bunchgrasses compared to the control. The coefficients of variation at plant functional group and species level in the LG and MG treatments were lower (P < 0.05) than in the control and HG treatments. Peak standing crop variability of the control and HG community were greatest, which suggested that LG and MG have greater ecosystem stability.


Assuntos
Ecossistema , Poaceae/crescimento & desenvolvimento , Ovinos/fisiologia , Animais , Conservação dos Recursos Naturais , Herbivoria , Mongólia , Chuva
2.
Plants (Basel) ; 13(18)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39339599

RESUMO

Winter rapeseed (Brassica rapa) has a good chilling and freezing tolerance. inducer of CBF expression 1 (ICE1) plays a crucial role in cold signaling in plants; however, its role in Brassica rapa remains unclear. In this study, we identified 41 ICE1 homologous genes from six widely cultivated Brassica species. These genes exhibited high conservation, with evolutionary complexity between diploid and allotetraploid species. Cold stress induced ICE1 homolog expression, with differences between strongly and weakly cold-tolerant varieties. Two novel ICE1 paralogs, BrICE1 and BrICE2, were cloned from Brassica rapa Longyou 6. Subcellular localization assays showed that they localized to the nucleus, and low temperature did not affect their nuclear localization. The overexpression of BrICE1 and BrICE2 increased cold tolerance in transgenic Arabidopsis and enhanced reactive oxygen species' (ROS) scavenging ability. Furthermore, our data demonstrate that overexpression of BrICE1 and BrICE2 inhibited root growth in Arabidopsis, and low temperatures could induce the degradation of BrICE1 and BrICE2 via the 26S-proteasome pathway. In summary, ICE1 homologous genes exhibit complex evolutionary relationships in Brassica species and are involved in the C-repeat/DREB binding factor (CBF) pathway and ROS scavenging mechanism in response to cold stress; these regulating mechanisms might also be responsible for balancing the development and cold defense of Brassica rapa.

3.
Front Microbiol ; 13: 1013913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36452921

RESUMO

Sweet sorghum is an important forage in arid and semi-arid climatic regions. This study aimed to reveal the fermentation weight loss (FWL), fermentation quality, and bacterial community of ensiling of sweet sorghum with lactic acid bacteria LAB; (Lactiplantibacillus plantarum and Lentilactobacillus buchneri) at different silo densities. For this study, sweet sorghum was harvested at the first spikelet of inflorescence stage and ensiled without or with LAB (CK or L) in polyethylene laboratory-scale silos (diameter, 20 cm; height, 30 cm) at densities of 650 (CK_650 and L_650), 700 (CK_700 and L_700), and 750 kg/m3 (CK_750 and L_750), respectively. The FWL, fermentation quality, microbial counts, and bacterial community of the silage were assessed after 100 days of ensiling. L_750 had a lower FWL than CK_650, _700, and _750 after 100 days of ensiling (P < 0.005), and the FWL was affected by silo density and inoculating LAB (P < 0.005). All silages had low pH (<4.0) and ammonia nitrogen content (<50 g/kg total nitrogen) and did not contain propionic and butyric acids; moreover, inoculating LAB increased lactic and acetic acids (P < 0.005). Bacterial communities in inoculated and uninoculated silages were clustered together, respectively, and clearly separated from each other. The total abundance of Lactiplantibacillus and Lentilactobacillus in fresh forage was <1%. Lactiplantibacillus had the highest abundance in all silages (from 71.39 to 93.27%), followed by Lentilactobacillus (from 3.59 to 27.63%). Inoculating LAB increased the abundance of Lentilactobacillus in each silo density (P < 0.005) and decreased Lactiplantibacillus in the silage in densities of 700 and 750 kg/m3 (P < 0.005); moreover, increasing silo density decreased Lactiplantibacillus abundance and increased Lentilactobacillus abundance in inoculated silages (P < 0.005). Overall, sweet sorghum silage showed satisfactory fermentation quality, with a density of no <650 kg/m3, and inoculating LAB improved fermentation quality and reduced FWL. Lactiplantibacillus and Lentilactobacillus presented as minor taxa in fresh sweet sorghum and dominated the bacterial community of all silages. Inoculating LAB was the main factor affecting the bacterial community of sweet sorghum silage. Moreover, inoculating LAB and increasing silo density can contribute to the decreasing Lactiplantibacillus abundance and increasing Lentilactobacillus abundance.

4.
Artigo em Inglês | MEDLINE | ID: mdl-25435607

RESUMO

BACKGROUND: Chaihu Guizhi has the effects of treating exogenous wind-cold; alternating episodes of chills and fever; noisy nose and retching; strong headache; chest and rib-side pain, and fullness, in clinical practice, it can also be used for the treatment of depression. The objective of this paper was to study the anti-depressant effect of Chaihu Guizhi decoction and its mechanism. MATERIALS AND METHODS: The anti-depressant effect of Chaihu Guizhi decoction was investigated by forced swimming test, tail suspension test and antagonism of reserpine hypothermia test in mice. RESULTS: Chaihu Guizhi decoction could significantly shorten immobility time of mice in the forced swimming test, and dose-dependence significantly shorten immobility time of mice in the tail suspension test, after administration of 50, 100, and 200mg/kg, Chaihu Guizhi decoction, a significant dose-dependent antagonism of reserpine-induced hypothermia was observed in mice of each treatment group. CONCLUSION: Chaihu Guizhi decoction has an antidepressant effect.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Animais , Depressão/fisiopatologia , Modelos Animais de Doenças , Elevação dos Membros Posteriores , Humanos , Masculino , Camundongos , Natação
5.
Artigo em Inglês | MEDLINE | ID: mdl-25435609

RESUMO

BACKGROUND: Chai Hu has the hepato-protective, choleretic, anti-tussive, analgesic, anti-inflammatory, anti-viral, hypotensive, hypolipidemic, and anti-tumor pharmacological effects. In this study, the objective of this paper was to study the anti-depressant effect of total saikosaponins. MATERIALS AND METHODS: Total saikosaponins were extracted by reflux method, and were identified by thin layer chromatography (TLC). The anti-depressant effect of total saikosaponins was investigated in vitro by tail suspension test, forced swimming test, and reserpine antagonism test in mice. RESULTS: Two times of reflux extraction, temperature of 70°C, and extraction time of 4hrs, for each extraction could improve the yield of saikosaponins. Each treatment group (100, 200, and 300 mg/kg), could significantly shorten the immobility time of mice in the tail suspension test in a somewhat dose-dependent manner. The total saikosaponins antagonized the reserpine-induced akinesia, and ptosis in mice. CONCLUSION: Total saikosaponins have an anti-depressant effect.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Ácido Oleanólico/análogos & derivados , Saponinas/administração & dosagem , Animais , Comportamento Animal/efeitos dos fármacos , Depressão/psicologia , Modelos Animais de Doenças , Elevação dos Membros Posteriores , Humanos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Ácido Oleanólico/administração & dosagem
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