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1.
为探讨低干矮冠多主枝开心树形对板栗产质性能的影响,以10年生‘金丰’板栗为试材,采用将整树冠层分层的方法,研究了低干矮冠多主枝开心树形的树体结构参数及不同冠层间板栗总苞的分布特征。结果表明:在垂直方向上,结果枝和总苞的分布主要集中在树体的中上部,下部有少量分布,其中结果枝和总苞均在1.0~1.5 m层间最多,而每果枝总苞数量在冠层两端最多。在水平方向上,发育枝、结果枝和总苞数量随冠层外移逐渐增多,集中分布于0.5~2.5 m的冠层范围,分别占总量的87.9%、89.9%和88.2%,其中结果枝和总苞在1.5~2.0 m的层间数量最多,体现了该树形立体结果的效果。该树形在保证坚果品质的同时,产量较自然开心形和自然圆头形提高30%以上。 相似文献
2.
《经济林研究》2014,(2)
为揭示板栗总苞、坚果等表型性状的变异程度及不同表型性状间的相关关系,分别采用描述性统计分析法、方差分析法、Duncan多重比较法和相关分析法对部分板栗种质的总苞与坚果的10个表型指标进行了分析。研究发现:板栗总苞长度、宽度、高度及坚果高度、宽度、厚度6个性状的变异较小,变异系数均在5%~10%之间;总苞体积、总苞质量以及坚果质量、坚果体积4个性状的变异较大,变异系数多在10%~25%之间,表型多样性丰富,处于较高水平;不同种质间存在不同程度的表型差异;板栗总苞质量与总苞长度、宽度、高度及坚果高度、厚度、质量呈正相关,坚果质量与总苞质量及坚果长度、宽度、厚度呈正相关,与总苞长度、宽度、高度无显著相关关系;总苞发育与其内部坚果发育在质量上互呈正相关。 相似文献
3.
粘底板板栗是安徽舒城绿化公社常院一带的主栽品种,因其总苞内茸层较厚,坚果底座大而深嵌在总苞内,以致坚果成熟后总苞开裂,坚果不落;即使过熟(总苞落地)坚果仍附着于总苞内不掉,所以被当地群众称之为“粘底板”。粘底板幼树较直立,结果大树树形开张呈半圆形或圆头形。主干褐色,有灰白斑,枝条粗壮,黄褐色,芽大。新梢密被黄色茸毛,老熟枝条只有顶部有茸毛。叶片中等大小,为披针状椭圆形,先端渐尖,基部楔形。幼叶背面密被白色长茸毛,叶面沿叶脉有白色短茸毛,叶色深绿,叶面皱,具光泽。混合芽大而饱满,多着生干结果母枝顶端以下数芽(一般是1—4芽)。每一结果母枝能萌发2—4个结果枝(混合花枝),每一结果枝上有雌花穗 相似文献
4.
<正>1良种1.1燕山红栗又名燕红。原株为40多年生的实生树,生长在北京市昌平县北庄村,故又称北庄一号。该品种树形中等偏小,树冠紧凑,结果枝比例高,早产丰产。总苞椭圆形,壳薄,刺束较稀,出籽率高。坚果果面茸毛少;果皮红棕色,富光泽,平均果重8.9g,果肉甜,糯性,含糖20.25%,含蛋白质 相似文献
5.
用 BR、GA3 、PP3 3 3 、KH2 PO4 、H3 BO3 共 5种化学调节物质进行了叶面喷布试验 ,观察它们在板栗开花结果上的效应。结果表明 ,不同药剂、浓度及药剂组合对板栗母枝平均结果枝数、长度、每结果枝雌花序数 ,母枝平均雄花枝数 ,单果质量 ,三果率和空苞率的影响有明显的差异。综合考虑化学调节物质在提高板栗雌花量和果实产量 ,以及降低空苞率上的试验效果 ,最佳的化学处理为 BR0 .0 1mg· L-1 PP3 3 3 1g· L-1 KH2 PO4 7.5g· L-1 H3 BO3 5.0 g· L-1,可使板栗结果枝数目平均由 1.2个增加至 2 .833个 ,结果枝平均雌花数由 1.56 7个增加到 1.8个 ,平均空苞率由 30 .70 %降至 9.0 3% 相似文献
6.
通过实地调查,对湖北省20个板栗地方品种的10个性状,利用SAS软件进行了板栗品种的Q型聚类及其10个性状的R型聚类分析.Q型聚类将20个板栗品种分成3组,每组都存在着明显的特点①油栗型品种,坚果小、晚熟、耐贮藏,适于炒食或贮藏保鲜,延后上市.②大果型品种,坚果特大,适于菜用或加工,中熟或中晚熟.③中果型品种,坚果中等大,成熟上市较早,适于鲜食.R型聚类分析揭示了性状之间的相对关系,把10个性状分成了3组,8个形质性状最先聚合在一起成为一组,2个数量性状彼此独立.坚果平均质量、总苞平均质量是不稳定的数量性状.根据总苞和坚果性状编制了湖北省板栗品种检索表,就湖北省板栗品种结构调整提出了建议. 相似文献
7.
通过实地调查，对湖北省20个板栗地方品种的10个性状利用SAS软件进行了板栗品种前Q型聚类及其10个性状的R型聚类分析，Q型聚类将20个板栗品种分成3组，每组都存在着明显的特点：（1）油栗型品种，坚果小，晚熟，耐贮藏，适于炒食或贮藏保鲜，延后上市，（2）大果型品种，坚果特大，适于菜用或加工，中熟或中晚熟，（3）中果型品种，坚果中等大，成熟上市较早，适于鲜食，R型聚类分析揭示了性状之间的相对关系，把10个性状分成了3组，8个形质性状最先聚合在一起成为一组，2个数量性状彼此独立，坚果平均质量，总苞平均质量是不稳定的数量性状，根据总苞和坚果性状编制了湖北省板栗品种检索表，就湖北省板栗品种结构调整提出了建议。 相似文献
8.
板栗空苞形成原因及控制对策 总被引：1，自引：0，他引：1
板栗空苞,俗称空蓬、“哑苞”,即球苞中的坚果不发育或仅留种皮。经过对河南桐柏县板栗产区的调查发现,板栗的空苞现象非常普遍,平均达到25%左右,有些高达40%以上,是影响板栗产量的重要因素,给栗农造成了极大损失。根据多年的实践和探索,笔者总结出了板栗空苞形成的原因及其一些控制措施。 相似文献
9.
通过对板栗总苞在树冠中分布规律和结果母枝不同部位芽抽生结果枝能力的研究提出：板栗的总苞集中分布在树冠表面０～５０ｃｍ的冠层内,存在着严重的结果表面化现象;其主要原因是内光照严重不足,结果母枝中部无芽和随着芽位的增加芽抽生结果枝能力逐渐减弱,改善树冠内膛光照条件和培养粗壮的结果母枝是板栗修剪的主要任务,在板栗修剪中的不宜采用短截的修剪方法。 相似文献
10.
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
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.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
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.
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 > Tithonia ≥ Euphatorium > 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
14.
《Scandinavian Journal of Forest Research》2012,27(2):118-130
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
15.
Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
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
16.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
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
17.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
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
18.
Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
19.
《Wood material science & engineering》2013,8(2):76-84
Abstract Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists. 相似文献
20.
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