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《林业与环境科学》2021,(2)
研究通过对比不同硒源处理中竹荪Dictyophora echinovolvata硒子实体营养成分含量差异,探讨不同硒源对竹荪子实体中营养成分含量的影响。试验设置纳米硒、富硒氨基酸液肥、螯合硒3种硒源,每种硒源选择5、10 mg/L 2种施用浓度。结果表明:施用5 mg/L的富硒氨基酸液肥利于促进竹荪子实体中蛋白质的合成,施用5 mg/L的富硒氨基酸液肥、10 mg/L螯合硒利于竹荪子实体中粗多糖的合成,施用10 mg/L纳米硒利于竹荪子实体中硒元素的吸收存储,施用10 mg/L的螯合硒和纳米硒竹荪子实体中氨基酸总量较大,施用5 mg/L纳米硒可以有效提高竹荪子实体中风味氨基酸占氨基酸总量的比例,施用10mg/L螯合硒、5 mg/L纳米硒后可以有效提高竹荪的抗氧化功能。 相似文献
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把3种金属同时制成纳米级的粉末,每小时能生产500克纳米金属,所研制的自修复剂产品添加到润滑油中,可以显著降低润滑油的摩擦系数,这是前不久通过国家级科技鉴定的"纳米金属粉体连续制备技术"和"高性能纳米金属/陶瓷复合润滑自修复剂产品"两个项目的三大优势. 相似文献
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芦苇浆纳米纤维素的制备工艺条件优化及形貌分析 总被引：3，自引：1，他引：2
采用硫酸水解芦苇浆制备纳米纤维素,并用正交试验优化了工艺参数,分析了硫酸质量分数、反应温度和水解时间对芦苇浆制备纳米纤维素得率的影响.用透射电镜表征了芦苇浆制备的纳米纤维素的形貌.结果表明硫酸水解芦苇浆制备纳米纤维素的3个工艺参数对其得率的影响为硫酸质量分数的影响最大,反应温度的影响次之,而水解时间的影响较小;硫酸水解芦苇浆制备纳米纤维素的优化工艺条件为硫酸质量分数52％,反应温度47℃,水解时间4h,此条件下纳米纤维素得率最高(82.81％).芦苇浆制备的纳米纤维素经透射电镜观察呈棒状,纤维素长度达到纳米级. 相似文献
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为探究光周期在异色瓢虫雌虫卵巢和脂肪体发育过程中的作用以及明确二者之间关系,研究了20℃条件下异色瓢虫雌虫在13个光周期组合下卵巢和脂肪体发育情况,结果表明:在光照时间多于14h(包括14h)时,76%以上的雌虫卵巢发育集中在Ⅳ级、Ⅴ级,全部脂肪体发育为1级或2级,此时卵巢管长度为962.42~1 095.76μm,显著长于短光照下的卵巢管长度;在光周期为10L∶14D时,94.12%雌虫卵巢发育为Ⅰ级、Ⅱ级,卵巢管长度最短,为213.33μm,88.2%的脂肪体发育等级为3级,脂肪体发育水平最高;在光周期为2L∶22D、4L∶20D、6L∶18D、8L∶16D、12L∶12D时,卵巢的5个发育等级同时出现,且发育为Ⅲ级的个体占到了总体的40%;卡方检验显示,异色瓢虫雌虫卵巢与脂肪体发育呈负相关。 相似文献
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Chemical control of mistletoe (Viscum album L.) . Spraying or trunk injection of phytohormones has given promise of control of mistletoe (Viscum album L.) on silver fir. Definlte results were obtained some months after spring treatment, and autumn treatments appear equally promising. If these results are confirmed, the infection rate in low-elevation silver firs stands could be reduced. 相似文献
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Many bottomland tree species are tolerant of compacted soil and perform well in urban environments; however, the mechanism underlying this tolerance is unknown. Increased soil water content has been shown to alleviate some of the effects of soil compaction on plant growth, presumably because increasing soil water reduces soil strength. We hypothesized that tree species tolerant of very wet soils would have opportunities for root growth in compacted soil when high soil water contents reduced soil strength, whereas species intolerant of bottomland conditions would not. We tested this hypothesis on flowering dogwood (Cornus florida L.), a mesic species intolerant of inundation, and silver maple (Acer saccharinum L.), a bottomland species. Seedlings of both species were grown in pots for 21 and 30 days, respectively, in a growth chamber in native loam soil maintained at various combinations of soil strength and soil water tension. Downward root growth rate decreased in response to increasing soil strength in both species. At low soil strength (0.6 MPa), downward root growth rate of dogwood seedlings slowed when soil was either excessively wet or dry, whereas root growth rate of silver maple seedlings increased linearly with soil water content. In moderately compacted soil (1.5 g cm(-3) bulk density), silver maple seedlings had greater root growth rate, root length per plant, and ratio of root length to root dry weight in wet soil (0.006 MPa soil water tension) than in moist and dry soils (0.026 and 0.06 MPa, respectively), even though mean oxygen diffusion rate (ODR) was only 0.28 &mgr;g cm(-2) (SE = 0.05). No such effect was detected in highly compacted soil (1.7 g cm(-3) bulk density) in either species. Mean ODR showed a weak positive correlation with soil water tension (r = 0.40, P = 0.07), but was unrelated to soil strength. We conclude that silver maple roots can grow in moderately compacted soil when high soil water content decreases soil strength, whereas dogwood is unable to take advantage of this opportunity. 相似文献
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Marjamaa K Kukkola E Lundell T Karhunen P Saranpää P Fagerstedt KV 《Tree physiology》2006,26(5):605-611
We partially purified peroxidase isoform fractions from xylem extracts of a gymnosperm, Norway spruce (Picea abies (L.) Karst.), and an angiosperm, silver birch (Betula pendula Roth.), to determine the participation of xylem-localized peroxidases in polymerization of different types of lignin in vivo. Several peroxidase fractions varying in isoelectric point values from acidic to basic were tested for their ability to catalyze the oxidation of the monolignols coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol in vitro. All of the xylem peroxidases extracted from Norway spruce and most of those from silver birch showed the highest rate of oxidation with coniferyl alcohol in the presence of hydrogen peroxide. The exception was an acidic peroxidase fraction (pI 3.60-3.65) from silver birch that exhibited higher oxidation activity for sinapyl alcohol than for coniferyl alcohol. For the xylem enzyme fractions extracted from silver birch, the ability to oxidize the artificial phenolic substrate syringaldazine coincided with high specific activity for sinapyl alcohol. Therefore, we conclude that the acidic, neutral and basic xylem peroxidases of Norway spruce all function in the synthesis of guaiacyl-type lignin, whereas in silver birch the acidic peroxidases preferentially oxidize sinapyl subunits. The latter provides a mechanism for synthesis of guaiacyl-syringyl lignin typical of tracheid cell walls in angiosperm trees. 相似文献
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生长素IBA对核桃室内嫁接愈合率的影响 总被引：1，自引：0，他引：1
核桃室内劈接或切接时,应用不同浓度的生长素IBA快蘸辽核一号接穗1~3 s,并采用500 mg/L的生长素IBA分品种进行生产应用,研究结果表明:最高愈合率100%,平均91%,较对照提高25%,因此,用500 mg/L的IBA溶液对核桃室内劈接或切接的愈合率有显著的促进作用。 相似文献
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非洲菊切花保鲜剂的研究 总被引：15，自引：0，他引：15
本文研究由蔗糖、硝酸银、8-HQ(8-羟基喹啉)配制的不同保鲜剂对非洲菊切花插瓶寿命、水分平衡、鲜重变化及观赏值等指标的影响。结果表明：4％蔗糖 200mg／L硝酸银 200mg／L硫酸铝 320mg／L8-HQ的保鲜效果最好。 相似文献
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外源激素对银杏高位嫁接及其枝梢生长的影响 总被引：2，自引：0，他引：2
用正交试验方法L9(34)研究了3种植物生长调节物质(IAA、GA3、NAA)以及3种浓度(50、100、200 mg/L)和3种处理时间(浸沾1 s、浸泡1 min、10 min)对银杏高位嫁接成活率与枝梢生长的影响.结果表明:采用IAA和NAA能够提高银杏嫁接成活率,最好组合是A3C2D1,成活率达99.3%,枝梢生长达128.3 cm,而GA3则对嫁接成活率有一定的抑制作用;在银杏嫁接时,IAA对银杏嫁接成活率和枝梢生长影响较大;不同时间的处理,激素对嫁接的效果也不同. 相似文献
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We investigated whether timing and rate of growth are related to the life strategies and fitness of three conifer species. Intra-annual dynamics of wood formation, shoot elongation and needle phenology were monitored over 3 years in five Norway spruces (Picea abies (L.) Karst.), five Scots pines (Pinus sylvestris L.) and five silver firs (Abies alba Mill.) grown intermixed. For the three species, the growing season (delimited by cambial activity onset and cessation) lasted about 4 months, while the whole process of wood formation lasted 5-6 months. Needle unfolding and shoot elongation followed the onset of cambial activity and lasted only one-third of the season. Pines exhibited an 'extensive strategy' of cambial activity, with long durations but low growth rates, while firs and spruces adopted an 'intensive strategy' with shorter durations but higher growth rates. We estimated that about 75% of the annual radial increment variability was attributable to the rate of cell production, and only 25% to its duration. Cambial activity rates culminated at the same time for the three species, whereas shoot elongation reached its maximal rate earlier in pines. Results show that species-specific life strategies are recognizable through functional traits of intra-annual growth dynamics. The opposition between Scots pine extensive strategy and silver fir and Norway spruce intensive strategy supports the theory that pioneer species are greater resource expenders and develop riskier life strategies to capture resources, while shade-tolerant species utilize resources more efficiently and develop safer life strategies. Despite different strategies, synchronicity of the maximal rates of cambial activity suggests a strong functional convergence between co-existing conifer species, resulting in head-on competition for resources. 相似文献