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1.
为了解不同油茶品系的养分利用及土壤养分限制情况,以岑软2号(Camellia oleifera Cenruan 2)、岑软3号(Camellia oleifera Cenruan 3)和香花油茶1号(Camellia osmantha 1)为研究对象,分析不同油茶品系叶片与土壤碳(C)、氮(N)和磷(P)含量及其化学计量特征。结果表明,叶片C和P含量均表现为香花油茶1号>岑软2号>岑软3号,叶片N含量表现为香花油茶1号>岑软3号>岑软2号。不同油茶品系叶片N∶P均为14~16,均受N和P的双重限制。随土层深度增加,土壤C、N和P含量降低,土壤C∶P、N∶P增加。岑软2号、岑软3号叶片C、N和P含量及其化学计量特征与土壤相关指标多呈显著负相关,香花油茶1号叶片N、P含量与土壤N∶P均呈显著正相关。不同油茶品系的生长均受N、P限制;随土层深度增加,植物生长可能受P限制。  相似文献   

2.
为给油茶(Camellia oleifera)果实发育期间的管理和营养调控提供理论依据和实践指导,以岑软3号油茶为研究对象,探索其落果规律与叶片营养元素含量的变化。结果显示,岑软3号油茶3个落果阶段分别为1月上旬-3月上旬、4月上旬-5月下旬和8月上旬-10月上旬,落果率分别为12.99%、40.26%和14.29%;在对油茶林进行营养调控时,建议冬季休眠前的施肥应对本研究测定的全部营养元素进行不同程度的补充,夏季施肥应适当补充氮、磷、钾、铜、钙、锌和镁。  相似文献   

3.
油茶组培苗生根过程中生理生化指标的变化   总被引:1,自引:0,他引:1  
为了探明油茶组培苗生根机理,提高油茶组培苗生根率,以"湘林1号"油茶无性系组培苗为材料,对其生根过程中营养物质、酶活性及内源激素变化规律开展了研究。结果表明:油茶组培苗属皮部生根类型;油茶组培苗生根过程中可溶性蛋白含量一直下降,可溶性糖含量呈现"升高—降低—升高"的趋势;POD活性在根原基诱导和表达期较低,而在不定根诱导和表达期迅速升高,PPO活性呈现先升高后降低的趋势;内源IAA含量呈"M"型变化,总体呈上升趋势,内源ABA含量呈现"W"型变化趋势,ZR含量呈先上升,后下降,再上升的变化趋势,GA含量呈现"上升—下降—上升"的趋势,整体呈现上升趋势。  相似文献   

4.
【目的】为了研究广宁红花油茶中非结构性碳水化合物(可溶性糖、淀粉和总NSC)在果实成熟期的变化趋势及分配规律,【方法】选定临近果实成熟期的4个采样点分别对广宁红花油茶Camellia semiserrata的2个新品种'红羽1号'红羽2号'的叶片、果皮、种壳和种仁4个部位进行测定。【结果】叶片、果皮和种仁中的可溶性糖随着采样时间的延长,其含量整体呈上升趋势,而种壳中的可溶性糖含量则呈下降趋势,可溶性糖含量在2.58~40.40 mg/g之间波动;叶片、果皮和种仁中淀粉含量随着时间延长呈下降趋势,种壳中淀粉含量则呈上升趋势,且淀粉含量在3.11~27.52 mg/g之间波动;叶片和种仁中总NSC含量随着时间延长,呈上升趋势,果皮和种壳中的总NSC含量呈下降趋势,总NSC含量在5.46~64.26 mg/g之间波动,且表现出显著的组织特异性。可溶性糖、淀粉和总NSC含量在种仁中最高,其次为叶片、果皮和种壳;种仁中可溶性糖含量是叶片中可溶性糖含量的1~2倍,而种仁和叶片中的NSC、淀粉含量相当,可溶性糖、淀粉和总NSC在种仁与叶片、种仁与果皮中的比值均保持不变,而可溶性糖、总NSC在种仁与种壳中的比值变化较大,随着成熟期的临近,二者比值逐渐增加,而种仁/种壳淀粉含量的比值是先升高后降低。各组分间的相关性分析表明,叶片NSC与叶片可溶性糖、种壳NSC与种壳可溶性糖、果皮NSC与果皮淀粉含量均呈现极显著正相关(P 0.01),叶片NSC与种壳淀粉含量间呈显著正相关(P 0.05),果皮NSC与种仁可溶性糖间呈极显著负相关(P 0.01)。【结论】在临近采收期,5个组织部位样品中非结构性碳水化合物趋于稳定,且品种间不存在差异性。  相似文献   

5.
以产自广西的4个油茶Camellia oleifera品种‘桂无1号’(桂1)、‘桂无4号’(桂4)、‘岑软2号’(岑2)和‘岑软3号’(岑3)的一年生嫁接苗为试材,通过PEG 6000模拟干旱胁迫,分别对其设置10%、20%和30%共3个浓度梯度,给予持续12、24、36 h以及营养液恢复12 h处理,测定幼苗各处理的生理指标,并用隶属函数分析法综合评价4个油茶品种幼苗的抗旱性。结果表明:干旱胁迫下,4个油茶品种幼苗叶片相对含水量均小于对照,其中桂1和桂4下降幅度最大;相对电导率、丙二醛、可溶性蛋白含量随着胁迫时间延长而呈上升趋势;胁迫处理36 h后,桂1和桂4的叶绿素含量显著降低,而岑2和岑3的叶绿素含量升高且始终维持在较高水平;岑2和岑3的可溶性糖含量增幅较桂1和桂4明显。复水后,岑2和岑3较多生理指标有恢复迹象。隶属函数分析表明,4个油茶品种幼苗的抗旱能力排序为岑软3号岑软2号桂无1号桂无4号。  相似文献   

6.
为了解油茶(Camellia oleifera)扦插生根过程中营养物质含量的动态变化及其与插穗生根的关系,以清水为对照,用IBA、ABT6、NAA生根粉处理插穗,并对油茶嫩枝扦插生根过程中部分营养指标的含量进行了测定.结果表明:外源生长激素提高了插穗生根率,改善了生根性状,其中以IBA处理为最优;处理组与对照插穗的可溶性总糖质量分数、淀粉质量分数随时间变化趋势一致,均呈"下降—升高—下降"趋势,处理组出现的峰值均比对照早且高;总氮质量比变化呈"升高—下降—升高"趋势,处理组全氮含量在根的表达期均低于对照,但生根率均高于对照; C/N值呈现"下降—升高—下降"变化趋势,处理组C/N值变化曲线的峰值显著高于对照,C/N值越高的处理,其生根率越高.  相似文献   

7.
以7年生长林4号、40号、53号普通油茶为试材,研究油茶春梢发育期叶片和果实中主要矿质元素的变化规律。结果表明,不同品种的叶片和果实矿质元素含量存在差异,同一品种的叶片(新叶、老叶)和果实中主要矿质元素含量也显著不同,总体趋势为氮、钾元素含量显著高于磷元素,叶片中氮元素含量最高,果中钾元素含量最高。在春梢发育期,新叶中氮、磷、钾元素的含量高于老叶,并且随着春梢的生长发育,新叶中氮、磷、钾含量呈现出明显的下降趋势。三种元素的含量变化表现出极显著正相关关系,老叶中氮磷钾含量变化趋势则不明显,新叶与老叶中氮元素含量变化呈极显著正相关关系。与叶片中氮磷钾元素含量的变化趋势不同,果实氮元素含量总体呈下降趋势,磷、钾元素含量的变化不明显。果实矿质元素含量的变化与新叶矿质元素含量变化呈现出较强的相关性,而与老叶矿质元素含量变化相关性较弱。  相似文献   

8.
油茶不同无性系叶片营养元素吸收情况评价   总被引:3,自引:0,他引:3  
对油茶不同无性系叶片营养元素含量的测定,研究结果表明:油茶叶片营养元素N含量最高,其次是Ca和K,Cu含量最低;油茶不同无性系叶片营养元素差异均达到极显著水平;通过主成分分析结果,综合评价油茶不同无性系营养元素吸收情况,按综合得分排序依次是桂软3号、桂软2号、湘林A5、湘林70号、桂软1号、桂软11号、桂软22号、桂软24号、桂软23号。  相似文献   

9.
黎凤金 《绿色科技》2024,(5):144-147
为探究不同品种油茶耐盐性生理机制,以广西壮族自治区武鸣区为试验地点,设置“岑软2号”“岑软3号”“赣兴48”3个品种油茶处理,对不同品种油茶叶片色素含量、MDA含量和SOD活性3个方面进行评估,比较了不同品种油茶耐盐性生理机制。结果表明:不同品种油茶盐碱胁迫下叶片色素含量、MDA含量和SOD活性均存在显著差异,盐碱胁迫会导致油茶叶绿素a和叶绿素b的含量降低,其中,“岑软3号”油茶叶绿素a和叶绿素b含量下降幅度最大;“岑软2号”“岑软3号”油茶会增加类胡萝卜素的合成以抵御胁迫,而“赣兴48”油茶会减少类胡萝卜素的含量;“赣兴48”油茶更易受到氧化胁迫,从而产生更高的MDA含量;“岑软2号”“岑软3号”油茶具有更强的抗氧化能力,能够更有效地对抗盐碱胁迫导致的氧化伤害,其SOD活性上升幅度最大。研究可为油茶种植业的可持续发展和盐碱土壤治理提供科学依据。  相似文献   

10.
为了解涝渍胁迫下白桦体内可溶性糖和淀粉含量的变化,以2a生白桦实生苗为材料,研究了涝渍胁迫对白桦叶片和茎中可溶性糖和淀粉含量的影响及其之间的相关性。结果表明:在渍水处理条件下,叶片中可溶性糖和淀粉含量呈上升趋势,处理到第60天,可溶性糖和淀粉含量显著高于对照,分别比对照升高了27.1%和41.6%;在淹水处理条件下,叶片中可溶性糖和淀粉含量呈先升高后下降趋势,处理到第60天,淀粉含量显著高于对照,比对照升高了34.1%,而可溶性糖含量与对照差异不显著。在渍水处理条件下,茎中可溶性糖含量呈升高趋势,而淀粉含量呈先下降后升高趋势,处理到第60天,可溶性糖和淀粉含量都与对照差异不显著;在淹水处理条件下,茎中可溶性糖和淀粉含量都呈先上升后下降趋势,处理到第60天,可溶性糖含量显著低于对照,比对照降低了19.5%,而淀粉含量与对照差异不显著。在涝渍胁迫下,叶和茎中可溶性糖含量与淀粉含量均呈显著的正相关,其相关系数分别为0.790和0.623,并且叶片可溶性糖含量与茎中可溶性糖含量也呈显著的正相关,相关系数为0.674。以上结果表明,糖和淀粉的存储和消耗对提高白桦耐涝能力有着积极的生理作用。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

14.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

16.

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.  相似文献   

17.
18.

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.  相似文献   

19.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

20.
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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