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1.
欧洲栓皮栎种子催芽试验   总被引:1,自引:1,他引:0  
欧洲栓皮栎 (Quercus rariabilis Bl.)是一种重要的软木工业原料。 6 0年代从苏联引种我省 ,由于疏于管理 ,目前 ,全省仅存 10 0株 ,濒于绝迹。为了拯救优良物种 ,加大欧洲栓皮栎种质资源收集 ,加速物种繁殖。实生繁殖时 ,为了确定合理的播种量以及改进种子贮藏方法 ,对种子进行不同药剂催芽处理 ,测定发芽率 ,平均发芽速 ,根的生长量 ,比较不同药剂对种子发芽的影响效果。表 2 种子发芽率表 (% )处理 4/ 1 2 1 3/ 1 2 2 2 / 1 2 31 / 1 2 9/ 1 1 8/ 1 (日 /月 )A12 46 381 82 86 932 6 70 80 8488902 96 5 80 8486 88A241 76 85 90 92 9…  相似文献   

2.
为了解栓皮栎种子虫蛀率的年际变化,及虫蛀率对林木种子出苗率及幼苗生长的影响,于2010年和2011年秋季,在国有济源市愚公林场,收集成熟栓皮栎种子,调查两年的虫蛀率;于2010年9月,分别种植完好和虫蛀的栓皮栎种子各50枚,定期观察记录其发芽和生长状况。结果表明:1)栓皮栎的虫蛀率在2010年为47%,在2011为50%,二者差异不显著;2)虫蛀栓皮栎种子的发芽率为52%,完好栓皮栎种子的发芽率为88%,二者差异较为显著;3)虫蛀栓皮栎苗的生物量为1 968±400 mg,而完好栓皮栎苗的生物量为2 920±300 mg,二者差异较为显著。由此可见,栓皮栎种子虫蛀率的年际变化不大,但虫蛀对种子的发芽和出苗率有直接影响,因此,在采用种子直播造林时,应尽可能选择完好种子,以减少虫蛀对建苗的影响,提高造林成活率。  相似文献   

3.
为研究栓皮栎的天然更新状况,进一步揭示其更新规律,以促进该地区栓皮栎林建康经营,采用典型样地调查法对小陇山林区栓皮栎的更新密度进行调查,通过灰色关联法对影响栓皮栎林天然更新的林窗、郁闭度、种子产量等因子进行关联性分析。结果表明:(1)栓皮栎针阔混交林下更新状况最好,更新密度为10 653株/hm~2;其中栓皮栎针叶混交林,更新密度为6 015株/hm~2;栓皮栎纯林林下更新密度最小,为5 458株/hm~2。(2)优势树种栓皮栎更新状况明显优于其他树种,更新密度最高可达6 100株/hm~2,频度可达80%。(3)影响栓皮栎更新的15个环境因子关联度排序为:林窗林分密度种子产量土壤厚度年龄结构郁闭度林木健康程度林分长势物种多样性坡度成层性啮齿动物数量灌草盖度海拔枯枝落叶层厚度。(4)在15个因子中不可控制因子包括土壤厚度、种子产量、年龄结构、坡度、海拔;可控制因子包括林窗、林分密度、郁闭度、林木建康程度、林分长势、物种多样性、成层性、啮齿动物数量、灌草盖度、枯枝落叶层厚度。为促进栓皮栎林天然更新,可通过营造栓皮栎针阔混交林以及对可控因子的调整来促进其天然更新,促进该地区栓皮栎林建康稳定生长。  相似文献   

4.
脱水敏感的栓皮栎种子贮藏方法研究   总被引:1,自引:0,他引:1  
栓皮栎为我国重要的造林树种和经济树种,但其种子贮藏对水分和温度要求比较苛刻,造成了栓皮栎种子贮藏困难.针对栓皮栎种子的脱水敏感性,对种子进行ABA浸种和清水浸种2种处理,以及采取室内沙藏、室外坑藏、控温冷藏等贮藏方法进行贮藏试验.研究得出自然风干条件下水分降低是栓皮栎种子生活力降低的主要因素,二者相关性高达0.925;栓皮栎种子的半致死含水量即安全含水量为46.31%;ABA对于提高栓皮栎种子的贮藏效果有显著的提升作用;栓皮栎种子在贮藏过程中需要适度低温,以略高于0℃为宜.  相似文献   

5.
不同种源栓皮栎种子形态和营养成分差异分析   总被引:1,自引:0,他引:1  
以28个栓皮栎种源种子为试验材料,对不同种源间栓皮栎种子的形态特征和营养成分含量差异进行比较分析。结果表明,不同种源间栓皮栎种子的长度、宽度和种子千粒质量以及可溶性糖、淀粉和蛋白质含量差异极显著。栓皮栎种子的长度和宽度变化幅度分别为1.56~2.38 cm和1.22~1.96 cm;种子千粒质量的变化幅度为1.45~5.45 kg;种子可溶性糖、淀粉和蛋白质含量的变幅分别为1.817%~6.325%、42.461%~80.274%和2.699%~9.694%。栓皮栎种子千粒质量与种子长度、宽度间呈极显著正相关,种子长度与宽度也极显著正相关;主成分分析表明,不同种源栓皮栎的差异主要是由种子千粒质量、宽度和长度决定。初步选出云南勐海、湖南城步1、安徽金寨1、重庆酉阳、山东蒙阴1、安徽旌德、安徽绩溪和安徽金寨2种源为优异种质资源。  相似文献   

6.
造林种子发芽率低一直是太行山干旱山区植被恢复过程中的一个难题。以该地区植被恢复中典型树种侧柏、栓皮栎种子为研究对象,通过控制试验,研究了不同土壤水分条件下不同保水剂包衣用量对侧柏、栓皮栎种子发芽率及生长发育的影响。结果表明,(1)盆栽用土为褐土,土壤含水率为5%时,保水剂包衣对侧柏种子发芽率及生长发育有显著的促进作用,并随用量的增加而增加,以施用保水剂比例1︰3时最佳;土壤含水率为8.5%时,保水剂用量过高则促进作用不明显,出芽率随用量增加而减小,施用保水剂比例1︰1及1︰2时能较好地提高侧柏种子出芽率;土壤湿度过高时,施用保水剂反而会抑制侧柏种子生长发育。(2)盆栽用土为砂页岩,土壤含水率为12%时,保水剂包衣能增加栓皮栎种子出芽率,施用保水剂比例1︰3时最佳;土壤含水率为20%时,保水剂包衣会抑制栓皮栎种子出芽率。  相似文献   

7.
栓皮栎种子及苗期种源变异分析   总被引:3,自引:1,他引:2  
收集了栓皮栎主要分布区12个种源的种子,对种子及播种苗进行了测定分析.结果表明,栓皮栎种子的大小、质量、发芽率及苗期的生长,在种源间均存在显著差异.栓皮栎中心分布区域种源的种子相对较大,发芽率较高,来自这些区域的种源苗期生长亦较旺盛.苗期生长的显著差异表明,栓皮栎种源间及种源内优良类型选育具有很大潜力.  相似文献   

8.
[目的]探讨水热条件变化后不同种源栓皮栎幼苗光合生理性状的差异,为栓皮栎优良种源的引种栽培提供理论参考。[方法]收集5个地理种源(北京平谷PG、河南内乡NX、湖北秭归ZG、江西永修YX和湖南城步CB)的栓皮栎种子,选择在其自然分布南缘以南的生境(广东鹤山,HS)下进行培育,测定不同种源栓皮栎的光合生理指标。[结果]表明:低纬度CB种源栓皮栎的潜在最大净光合速率(Pmax)显著高于中高纬的ZG和PG种源(P0.05);YX种源的表观量子效率(AQY)最高,而ZG种源的最低;NX和CB种源的叶绿素相对含量(SPAD)显著高于YX种源。PSⅡ原初光能转换效率(Fv/Fm)和PSⅡ潜在活性(Fv/F0)在各种源间均差异不显著,表明各种源栓皮栎均能较好地适应水热丰沛的新生境。同时,各种源栓皮栎在暗呼吸速率(Rd)、光饱和点(LSP)、光补偿点(LCP)、Rubisco酶最大羧化速率(Vcmax)、最大电子传递速率(Jmax)、光呼吸速率(Rp)、生长参数以及叶绿素荧光参数如电子传递速率(ETR)、光化学淬灭系数(qP)和非光化学淬灭系数(NPQ)等均差异不显著。[结论]各种源栓皮栎光合生理性状的异同与其自身遗传因素和较强的生态适应性有关。  相似文献   

9.
【目的】栓皮栎秋季子叶丢失与翌年春季出苗后子叶丢失是自然界的普遍现象,本试验旨在模拟2种丢失现象的交互发生,探究其叠加效应对种子营养物质转移及苗木生长状况的影响,揭示动物取食对栓皮栎幼苗更新的作用机制。【方法】以栓皮栎种子为试验材料,采用双因素裂区试验设计。播种前切除子叶远端,模拟秋季未取食(完整种子)、1/3(轻度)、2/3(重度)3个子叶丢失强度(主因素);出苗后,动态移除子叶,模拟翌年春季出苗后子叶丢失时间(副因素)(出苗后4、8、12、16、20、25、30天移除子叶),同时设置不移除对照组,模拟春季子叶未被取食。测定种子氮和碳水化合物动态含量变化,分析出苗过程中种子向苗木的物质转移规律;生长季末测定苗木成活率、生长、养分积累、非结构性碳水化合物等,分析子叶丢失强度与丢失时间对苗木生长状况的影响。【结果】1)春季出苗30天时,种子中淀粉向苗木的转移率最大(72.4%~89.36%),可溶性糖次之(66.61%~72.72%),氮最小(30.64%~59.45%)。2)秋季未丢失子叶的完整种子翌年春季种子向苗木的氮转移在出苗25天后完成,而秋季丢失子叶的种子春季向苗木转移氮的时间大幅缩短(8天)。3)主效应表明,秋季丢失2/3子叶导致苗高、地径分别降低30%、18%;副效应表明,翌年春季出苗20天前丢失子叶抑制苗木生长。4)交互效应表明,秋季未丢失子叶的完整种子,翌年春季出苗4天丢失子叶成活率仅为36.3%,生物量降低78.2%,25天前丢失子叶抑制养分和碳水化合物积累。秋季丢失1/3子叶的种子,翌年春季出苗4天后丢失子叶成活率降低65.2%,萌发25天后丢失子叶对苗木生长和营养物质积累几乎无影响。秋季丢失2/3子叶的种子,翌年春季无论子叶是否丢失,都会显著抑制苗木生长。【结论】翌年春季出苗后子叶丢失对苗木生长状况的作用不仅取决于丢失时间的早晚,而且受秋季子叶丢失程度的影响。因此,应充分考虑秋季子叶丢失强度和翌年春季子叶丢失时间的叠加效应,对于揭示栓皮栎更新机制具有重要意义。  相似文献   

10.
肖黄掌舟蛾Phalera assimilis(Bremer et Grey),又名栎掌舟蛾、栎黄掌舟蛾、彩节舟蛾、麻栎毛虫。属鳞翅目,舟蛾科,掌舟蛾属。我省各地均有发生,危害麻栎、栓皮栎、白栎、锥栎等栎属植物。在东至县国有梅城林场主要危害栓皮栎,大发生年份由于虫口密度大,短期内可将叶片吃光,严重抑制栎树生长。该场有栓皮栎林四千余亩,并被省林业厅定为栓皮栎种子园。为了保护栎类资源,生产更多的优良种子,探索经济有效的防治肖黄掌舟蛾方法,本人于2003年在该虫大发生期间,对此虫的生活习性及防治作了的观察研究,现报道如下。  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.
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.  相似文献   

14.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > TithoniaEuphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

15.

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   

16.

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   

17.
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   

18.

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.  相似文献   

19.

Mean age, mean and top heights and yield were studied in 20 mixed stands of birch ( Betula pubescens Ehrh. and B. pendula Roth) and Picea abies (L.) Karst. and nine mixed stands of birch and Pinus sylvestris L. in south-eastern Norway. Each mixed stand and the adjacent pure coniferous stand (control) were growing under the same site conditions and had not been commercially thinned. There were no significant differences in mean age at breast height or in top heights between birch and conifers in the mixed stands, while mean height was significantly higher for birch than for spruce. A growth index was calculated based on total volume and age at breast height. For the spruce sites the growth in young mixed stands (birch < 17 m) was superior to that of pure spruce, while the difference was insignificant in older stands. The growth index correlated positively with the ratio between generatively and vegetatively regenerated birch trees, and negatively with the age of the oldest species in the mixture and with site quality. For the pine sites there was no significant difference in the growth index between mixed birch-pine and pure pine stands. A mixture effect of birch on the volume yield of spruce or pine could not be demonstrated.  相似文献   

20.

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.  相似文献   

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