为进一步探明陕西省榆林市樟子松人工林的土壤养分变化特征,以5年生樟子松(Pinus sylvestris L. var. mongolica Litv.)纯林和5年生樟子松-胡枝子(Lespedeza bicolor Turcz.)混交林为研究对象,分析土壤有机质、硝态氮、有效磷、速效钾...为进一步探明陕西省榆林市樟子松人工林的土壤养分变化特征,以5年生樟子松(Pinus sylvestris L. var. mongolica Litv.)纯林和5年生樟子松-胡枝子(Lespedeza bicolor Turcz.)混交林为研究对象,分析土壤有机质、硝态氮、有效磷、速效钾等理化指标以及土壤酶活性的变化特征。结果表明,樟子松纯林和樟子松-胡枝子混交林土壤有机质、有效磷和速效钾含量整体上均随着土层深度的增加呈下降趋势,全磷含量均随着土层深度的增加呈先升高后降低的趋势,硝态氮含量则均随着土壤深度的增加而增加,5个指标均表现为樟子松-胡枝子混交林高于樟子松纯林,且樟子松-胡枝子混交林各层土壤有效磷含量均显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤含水率各土层间差异均不显著,樟子松-胡枝子混交林5~15 cm土层土壤含水率含量显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤碱性磷酸酶活性、过氧化氢酶活性、脲酶活性均随着土层深度的增加而降低,且樟子松-胡枝子混交林过氧化氢酶活性和脲酶活性在各土层均显著高于樟子松纯林(P<0.05)。展开更多
[ Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis (Bt) 00-50-5 strain against Trichoplusia ni Hub- ner. [Method] The crystals and spores of B. thuringiensis 00-50-5 s...[ Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis (Bt) 00-50-5 strain against Trichoplusia ni Hub- ner. [Method] The crystals and spores of B. thuringiensis 00-50-5 strain were first isolated and purified, and their insecticidal activities against T. ni were com- pared. [ Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain, or only pure crystals could kill T. n/larvae under the concentration of 100 p.g/mL after 48 h, and the mortality rate reached 100% ; pure spores could not kill the larvae. Determination results of median lethal concentration showed that in- secticidal activity of pure crystal of Bt 00-50-5 strain (LGs0 =0.32 p~/mL) was higher than the mixture of crystals and spores (LCs0 =0.48), but the insecticidal acti^ty of pure spores was very low (LC50 〉 500.00). Therefore, the crystals were primarily responsible for causing death of larvae. [ Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain.展开更多
Pure wheat malt beer (PWMB) with potentially functional properties may attract consumer interest.To explore the functional properties of non-starch polysaccharides (NSPs) in PWMB,NSPs were extracted from PWMB and sepa...Pure wheat malt beer (PWMB) with potentially functional properties may attract consumer interest.To explore the functional properties of non-starch polysaccharides (NSPs) in PWMB,NSPs were extracted from PWMB and separated into PWMB non-starch polysaccharides-1 (PNSP-1) and PWMB non-starch polysaccharides-2 (PNSP-2) by Q-Sepharose Fast Flow column.PNSP-1 exhibited more effects on increasing the viscosity of beers,which had higher purity of 92.58% containing 88.53% arabinoxylan with arabinose/xylose (A/X) 0.60 and 2.78% β-glucan but no glucomannan and mannan;while PNSP-2 showed greater effects on promoting beer haze and foam retention,which had more diverse NSPs including 46.03% arabinoxylan with A/X 1.13,41.47% arabinogalactan,10.26% glucomannan,and 2.70% mannan but no β-glucan.Diversity of sugar composition resulted in a better antioxidant capacity of PNSP-2.NSPs proliferated Lactobacillus casei LC6117 and LC0331,but did not promote L.plantarum LP-28 and L.fermentium LF-2H.PNSP-2 was also utilized by L.rhamnosus SRG.PNSP-2 had better effects on prebiotics activities.PNSP,PNSP-1 and PNSP-2 all exhibited mild inhibitory effects on α-glucosidase and lipase but not on α-amylase,and showed a binding capacity to fat and cholesterol.This work is of great reference significance for improving the viscosity,haze,foam retention and health value of wheat beer.展开更多
文摘为进一步探明陕西省榆林市樟子松人工林的土壤养分变化特征,以5年生樟子松(Pinus sylvestris L. var. mongolica Litv.)纯林和5年生樟子松-胡枝子(Lespedeza bicolor Turcz.)混交林为研究对象,分析土壤有机质、硝态氮、有效磷、速效钾等理化指标以及土壤酶活性的变化特征。结果表明,樟子松纯林和樟子松-胡枝子混交林土壤有机质、有效磷和速效钾含量整体上均随着土层深度的增加呈下降趋势,全磷含量均随着土层深度的增加呈先升高后降低的趋势,硝态氮含量则均随着土壤深度的增加而增加,5个指标均表现为樟子松-胡枝子混交林高于樟子松纯林,且樟子松-胡枝子混交林各层土壤有效磷含量均显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤含水率各土层间差异均不显著,樟子松-胡枝子混交林5~15 cm土层土壤含水率含量显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤碱性磷酸酶活性、过氧化氢酶活性、脲酶活性均随着土层深度的增加而降低,且樟子松-胡枝子混交林过氧化氢酶活性和脲酶活性在各土层均显著高于樟子松纯林(P<0.05)。
基金supported by Project for Introduced Talents in Environment and Plant Protection Institute of Chinese Academy of Tropical Agriculture(HZS1101)Fundamental Research Special Project for Central Public-interest Scientific Institutes(2012hzs1 J038,2012hzs1 J016)
文摘[ Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis (Bt) 00-50-5 strain against Trichoplusia ni Hub- ner. [Method] The crystals and spores of B. thuringiensis 00-50-5 strain were first isolated and purified, and their insecticidal activities against T. ni were com- pared. [ Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain, or only pure crystals could kill T. n/larvae under the concentration of 100 p.g/mL after 48 h, and the mortality rate reached 100% ; pure spores could not kill the larvae. Determination results of median lethal concentration showed that in- secticidal activity of pure crystal of Bt 00-50-5 strain (LGs0 =0.32 p~/mL) was higher than the mixture of crystals and spores (LCs0 =0.48), but the insecticidal acti^ty of pure spores was very low (LC50 〉 500.00). Therefore, the crystals were primarily responsible for causing death of larvae. [ Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain.
基金supported by the Key Technology Research and Development Program of Shandong(grant no.2016GNC110015).
文摘Pure wheat malt beer (PWMB) with potentially functional properties may attract consumer interest.To explore the functional properties of non-starch polysaccharides (NSPs) in PWMB,NSPs were extracted from PWMB and separated into PWMB non-starch polysaccharides-1 (PNSP-1) and PWMB non-starch polysaccharides-2 (PNSP-2) by Q-Sepharose Fast Flow column.PNSP-1 exhibited more effects on increasing the viscosity of beers,which had higher purity of 92.58% containing 88.53% arabinoxylan with arabinose/xylose (A/X) 0.60 and 2.78% β-glucan but no glucomannan and mannan;while PNSP-2 showed greater effects on promoting beer haze and foam retention,which had more diverse NSPs including 46.03% arabinoxylan with A/X 1.13,41.47% arabinogalactan,10.26% glucomannan,and 2.70% mannan but no β-glucan.Diversity of sugar composition resulted in a better antioxidant capacity of PNSP-2.NSPs proliferated Lactobacillus casei LC6117 and LC0331,but did not promote L.plantarum LP-28 and L.fermentium LF-2H.PNSP-2 was also utilized by L.rhamnosus SRG.PNSP-2 had better effects on prebiotics activities.PNSP,PNSP-1 and PNSP-2 all exhibited mild inhibitory effects on α-glucosidase and lipase but not on α-amylase,and showed a binding capacity to fat and cholesterol.This work is of great reference significance for improving the viscosity,haze,foam retention and health value of wheat beer.