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991.
红松种子园树木整形丰产技术的研究 总被引:4,自引:0,他引:4
近年来,东北三省营造了相当数量的红松(Pinus koraiensis Sieb.et Zucc.)无性系种子园,目前普遍存在结实偏低的问题。我所于1981—1986年在草河口红松无性系种子园进行了整形修剪实验,1986—1990年分别在草河口红松无性系种子园和本溪县清河城实验林场的红松无性系种子园,对促进结实效果明显的整形修剪技术进行了中试,取得了显著的增产效果。一、试验地概况试验地设在辽宁省本溪县草河口山城沟。位于东经123°51′,北纬40°53′,海拔200 相似文献
992.
质膜内在蛋白作为水通道蛋白的一种存在类型,在跨膜水分运输中起着重要作用。本研究以本实验室获得的水通道蛋白基因的EST序列为模板设计引物,利用RACE技术扩增得到1 174 bp的PsPIP2全长cDNA,其中,包括3'UTR 191 bp,5'UTR 137 bp和846 bp的编码区,共编码281个氨基酸,分子量为29.79 kD。PsPIP2包括8个可能的磷酸化位点,其中7个位于丝氨酸(S),1个位于酪氨酸(Y),推测这些磷酸化修饰位点可能与PsPIP2蛋白通道的开启与闭合相关。二级结构预测显示,PsPIP2含无规卷曲和α-螺旋较多。同源性分析结果表明,PsPIP2与木薯PIP2同源性最高。本研究结果可为研究该基因的生物学功能和牡丹花衰老调控机制提供理论基础。 相似文献
993.
板栗叶片过氧化物酶活性与树体生长发育的关系 总被引:9,自引:0,他引:9
对7个品种的板栗叶片过氧化物酶研究结果表明,板栗不同品种叶片的过氧化物酶活性存在着差异,矮化型品种的过氧化物酶活性明显高于一般品种.所测品种叶片的过氧化物酶活性均与冠经、树高、干周、新梢长度呈负相关.因此,可以把叶片过氧化物酶活性作为矮化型板栗品种早期预选的生化指标. 相似文献
994.
该试验以桃红颈天牛(Aromia bungii Faldermann)为试材,对大连市1~15年生桃园桃红颈天牛的发生规律、幼虫平均密度和桃树受害率进行系统调查。结果表明,大连市桃园桃红颈天牛二三年发生1代,羽化期从7月初开始,发生高峰期为7月末,幼虫为害桃树主干。随着树龄的增长,桃树受害率和桃红颈天牛虫口密度显著增加,其中17~20年生的桃树受害程度最重,受害率达到88%~96%。 相似文献
995.
Koranda M Schnecker J Kaiser C Fuchslueger L Kitzler B Stange CF Sessitsch A Zechmeister-Boltenstern S Richter A 《Soil biology & biochemistry》2011,43(3):551-558
Plant roots strongly influence C and N availability in the rhizosphere via rhizodeposition and uptake of nutrients. This study aimed at investigating the effect of resource availability on microbial processes and community structure in the rhizosphere. We analyzed C and N availability, as well as microbial processes and microbial community composition in rhizosphere soil of European beech and compared it to the bulk soil. Additionally, we performed a girdling experiment in order to disrupt root exudation into the soil. By this novel approach we were able to demonstrate that enhanced resource availability positively affected N mineralization and hydrolytic enzyme activities in the rhizosphere, but negatively affected nitrification rates and oxidative enzyme activities, which are involved in the degradation of soil organic matter. Both rhizosphere effects on N mineralization and oxidative enzyme activities disappeared in the girdling treatment. Microbial community structure in the rhizosphere, assessed by phospholipid fatty acid analysis, differed only slightly from bulk soil but was markedly altered by the girdling treatment, indicating additional effects of the girdling treatment beyond the reduction of root exudation. Differences in oxidative enzyme activities and nitrification rates between rhizosphere soil and bulk soil, however, suggest considerable differences in the (functional) microbial community composition. 相似文献
996.
Dissolved organic matter (DOM) derived from the humus layer under silver birch (Betula pendula Roth), Norway spruce (Picea abies (L.) Karst.), and mixed stands, and from senescent birch leaves and from spruce needles of the four oldest year-growth were characterized microbiologically and chemically. Samples were collected in the autumn and the solutions were obtained by centrifugation-drainage technique. The degradability of DOM, the availability of DOM to bacteria and fungi, concentrations of phenolic compounds and carbohydrates, and the distribution of carbon and nitrogen into fractions according to the chemical nature and the molecular size were studied. DOM derived from leaves and needles was clearly more labile than DOM derived from the humus layer indicating the importance of studying the DOM originating from fresh litter when assessing the turnover of DOM.DOM derived from spruce needles appeared to differ chemically greatly from all other samples. It had very high concentrations of carbohydrates, probably due to the sampling time, and phenolic compounds. The chemical composition of DOM derived from humus layer did not reflect the composition of DOM derived from needles and leaves. DOM derived from birch leaves degraded more than DOM derived from spruce needles and DOM derived from humus layer collected at the birch sites degraded more than DOM derived from humus layer collected at the spruce sites. The degradability of different compound groups of DOC and DON was studied in a short-term incubation (20 d) of DOM solutions by characterizing the solutions initially and after the incubation. Almost all compound groups appeared to degrade but weak hydrophobic acids, bases, hydrophilic neutrals, the smallest molecular size compounds, carbohydrates, and phenolic compounds degraded the most. 相似文献
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安徽淮河流域耐水湿树种的聚类分析及布局研究 总被引:4,自引:2,他引:4
1992年4至5月,对安徽省淮河流域前一年遭受特大水灾的8个县市树木生长情况进行了调查,并按所调查各县市的树种在受淹1一2月、水淹1一2m和受淹部位达到树干部的存活率,进行聚类分析,将其分别归入极耐水湿、较耐水湿、微耐水湿和不耐水湿4个等级。本文最后对治淮绿化工程耐水湿树种的选择和布局提出了建议。 相似文献