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脐橙果大美观 ,风味浓郁 ,经济价值高 ,是当今世界重点发展的亚热带果树良种。但由于国内目前普遍采用“幼砧、速生、高密度”繁育脐橙苗木 ,出圃的一年生幼苗大都只有两次梢 ,1～ 2个分枝 ,苗木高度及干径均达不到一级标准 ;定植后成活率低 ,生长缓慢 ,较难定干整形。为此 ,我们在实施农业部脐橙种植项目过程中 ,进行了一系列试验对比 ,采用袋装营养基质假植脐橙苗木 ,取得了较显著的效果和经济效益。采用袋装营养基质培育假植脐橙苗 ,须根数量比传统培育的同龄苗木增加 1 2 4 .7% ;根长增加近两倍 ;新梢抽发次数增加 1～ 2次 ;末级枝梢增… 相似文献
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<正>‘哈密大枣’传统的建园方法为苗木定植建园,其中包括苗圃育苗、起苗、保鲜、运输、假植、定植等一系列工序,每一个环节都不能疏忽,劳动强度大,综合成本高。这种建园方式明显的缺点是起苗过程根系损伤严重,定植成活率不高,当年生长量小,早期产量低。直接播种酸枣,次年嫁接,第3年按预定株行距留苗,多 相似文献
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1996年春，笔者在吉安市兴桥镇罗塘新开发果园，用营养袋假植脐橙苗900株、沙田柚400株、芦柑200株、1997年3月脱袋定植，成活率达100％，且树体长势健壮。要培育好营养袋假植大苗，须把好以下四个关。一、苗木选择关苗木要选品系纯正，无检疫性和其它严重的病虫害，根系发达，干粗的一、二级壮苗。二、营养土配制关配方可参照①1m3肥土加谷壳15kg或发酵锯木屑25kg、钙镁磷肥2kg、过筛垃圾23担、猪牛粪1～2担；②1m3肥土、谷壳15kg或发酵锯木屑25kg、菜籽枯饼5kg、氮磷钾复合肥2～3kg、石灰1kg。充分混合拌匀做堆，外用稀泥糊密封，堆沤30～… 相似文献
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我县大仲村镇1999年春引进丰水梨6年生大苗18500株,东西行向栽植,行株距6米×6米,定植面积66.7公顷,成活17571株,成活率95%。定植后第2年成花株率达80%,第3年总产梨果7.5千克,平均666.7平方米产75千克,第4年(2002年)总产26.36万千克,平均666.7平方米产277.5千克。经过几年的生产观察,该品种具有生长快、结果早、丰产稳产、品质优良等特点,深受消费者青睐。其建园和栽培技术要点如下。1选用优质大苗壮苗所栽梨树全部为6年生大苗,平均树高295厘米,干周24.7厘米,冠径250厘米。起苗前,先行灌足水,上部三大主枝留20厘米左右重短截,适当疏除过密枝… 相似文献
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通过同一品种、相同苗龄、同季定植的裸根苗直栽和营养袋大苗无伤根带土定植的甜橙苗木生长量和成活率的对比试验研究，结果表明：营养袋大苗无伤根带土定植消除了缓苗期，大幅度提高苗木成活率。 相似文献
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柑桔幼苗早春塑料袋盖膜假植１９９４春，笔者将约３０ｃｍ高的纽荷尔脐橙苗采用塑料食品袋假植，并于６月底前定植，取得了较好的效果，当年抽发４～５次梢，形成多个主枝，１５ｃｍ以上的末级梢达２０多条，为第２年生长打下了良好的基础。其具体方法是：１备土土壤用菜... 相似文献
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近年来,因苹果苗木供不应求,半成苗或三当苗已成为建园的主要形式,即便是2年生成苗,也往往苗的高度、粗度及根系的完好程度达不到规定要求,而且起苗时根系受损,加上远距离运输,使栽后成活率不高或成活后生长不良,缺株严重已成为普遍问题.为此建在建园时建立苹果假植区,即苗木运到后先在定植园附近将苗木较高密度栽植,这样不仅有利于建园时苗本的选择,提高成活率,而且有利于以后的缺株补植,使国貌整齐,假植地也应选择土地平整、灌水条件好的地方,假植苗木少时可在定植苗木的同时,将假植苗栽于定植区的株边或园边。假植株行距2m左右,上质较差… 相似文献
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推广种植大叶相思是闽南地区建设速生丰产林的一个重要途径,通过分别采用大田裸根育苗、容器育苗引种对比大叶相思实生苗和优良品质扦插苗造林的生长情况,经造林1年和5年生长调查,大叶相思四种苗木的造林保存率均达到89%以上,造林1年扦插容器苗的平均树高和胸径分别比裸根苗提高19.5%、15.7%,实生容器苗的平均树高和胸径分别比裸根苗提高12.6%、11.9%,造林宜优先考虑用容器苗。造林5年的扦插容器苗平均树高和胸径、单株蓄积量、单位面积蓄积量分别比实生容器苗提高15.2%、19.8%、62.1%、63.6%,没有发现寒害、风害和病虫害,说明大叶相思适应厦门坂头的气候和土壤,可以在厦门坂头种植,在推广造林时宜优先考虑运用优良品种苗木。5年生的实生容器苗与扦插容器苗的优势木树高和胸径分别比平均木提高31.2%、23.4%与23.5%、32.6%,说明林分还有很大的生长潜力,可以通过施肥等措施来促进林木的速生丰产。 相似文献
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Fabrício Packer Gonçalves Eduardo Sanches Stuchi Simone Rodrigues da Silva Eduardo Toller Reiff Lilian Amorim 《Scientia Horticulturae》2011
The production and commercialization of citrus seedlings inspected and produced in protected screenhouses has become mandatory in São Paulo State, Brazil since January 2003. This law was intended to avoid the dispersion of Citrus Variegated Chlorosis (CVC), disease caused by Xylella fastidiosa. Our objective was to compare the yield over 8 years of ‘Natal’ sweet orange trees grafted onto Rangpur lime obtained from healthy nursery plants and from plants artificially inoculated with X. fastidiosa. Yield was evaluated in an orchard planted in February 1999 with two treatments: (i) trees from healthy nursery plant, and (ii) trees from plants artificially inoculated with X. fastidiosa. The mean yield was 21% higher in trees from healthy nursery plants, as compared to trees from inoculated nursery plants. This difference represents a gain of approximately 203 boxes of 40.8 kg each, considering a planting density of 550 plants per hectare. 相似文献
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Climate change, human population growth, the energy crisis, and food insecurity negatively drive livelihoods in developing countries. The trend seems to be severe in arid and semi-arid areas where some livelihood strategies are naturally constrained. Tree planting is one of the mitigation and adaptation approaches applied to climate variability and change for sustainable development in sub-Saharan Africa. The current study assessed the status, determinants, and challenges of tree planting in Nkuhungu, Msalato, and Hombolo villages in the Dodoma district, Tanzania. A household questionnaire survey (HQS) was used to collect data from 213 household respondents. In-depth interviews and focus group discussions were used to supplement data from HQS. Results indicate that tree planting is practiced at household and institutional levels during the wet season and was promoted after the government shifted from Dar es Salaam to Dodoma. Approximately 5111 planted trees were recorded in the study villages, with an average of 24 ± 5 trees planted per household. Fruit and shade trees are widely planted in residential areas, and privately owned nurseries and the Tanzania Forest Services Agency (TFS) are the major sources of seedlings. Level of education (+), type of employment (-), seedling price (-), water availability (+), and the importance of the tree (+) were found to influence the number of trees planted by household respondents. The main challenges of tree planting are inadequate land size, water scarcity, high pricing of seedlings, lack of improved seeds, and insufficient extension services. Knowledge on tree planting determinants would be instrumental in strengthening the current governmental strategies for greening Dodoma. The study suggests increasing water sources such as boreholes and digging wells/ponds for watering trees; improvement of extension services; and provisioning of affordable improved and adaptive seeds to semi-arid areas. 相似文献
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J. W. Grosser J. L. Chandler 《The Journal of Horticultural Science and Biotechnology》2013,88(6):641-644
SummaryIncreasing losses of trees to diseases, expansion of plantings into more marginal production areas and the need to control tree size to reduce harvesting costs have elevated the demand for new improved citrus rootstocks in Florida. A major strategy of the CREC rootstock improvement programme has been to use protoplast fusion to produce allotetraploid somatic hybrids that combine complementary rootstock germplasm. Tetraploid citrus rootstocks have been shown to have a built-in tree size control component due to polyploidy. This report focuses on the incorporation of newly identified superior rootstock germplasm into the somatic hybridization programme. Poncirus trifoliata 50–7, a selection of trifoliate orange selected for superior resistance to Phytophthora nicotianae, was hybridized with sour orange, Changsha mandarin, Navel orange, and a seedy white ‘Duncan’ type grapefruit. High-yielding Benton citrange (Citrus sinensis 3 Poncirus trifoliata) was hybridized with Changsha mandarin and sour orange. More than 200 plants of each of these six new somatic hybrids were propagated via tissue culture and rooted cuttings. To assess their horticultural performance, all the somatic hybrids were budded with commercially important scions and planted in replicated trials representing the two most important soil types in Florida. Seed trees of each somatic hybrid have also been planted in the field to determine fruiting potential and level of polyembryony. 相似文献
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A.P. Preston 《The Journal of Horticultural Science and Biotechnology》2013,88(3):329-335
Trees of Cox's Orange Pippin on M.IXa, M.26 and MM. 106 were planted either normally with roots or without roots to simplify the planting operation. Pruning treatments were superimposed, the trees being cut back at planting, left unpruned the first year and cut back the second year, or left entirely unpruned. All trees survived. After two growing seasons the trees were lifted and weighed. Removal of all roots before planting reduced shoot growth, trunk girth increment, final tree weight and incremental weight. However, on all rootstocks, trees planted without roots and left unpruned were similar in size when lifted to those planted with roots and cut back at planting in the orthodox manner.In a complementary trial lasting one season Cox's Orange Pippin trees on M.26 were planted with or without roots. All trees were cut back at planting, and four times of planting were compared. The mid-April planting included trees that had been stored at 2.8 °C and trees that had been bedded-in outdoors. There were no tree losses attributable to removal of the roots before planting. Removing the roots at planting again reduced growth and weight of tree at lifting. Month of planting had no effect upon shoot growth or trunk girth increment.The results are discussed, together with their practical implications in relation to mechanical tree planting for high density orchards. 相似文献
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A. D. Webster S. P. Vaughan A. S. Lucas J. E. Spencer 《The Journal of Horticultural Science and Biotechnology》2013,88(5):680-688
SummaryThe apple cultivar Queen Cox on M.9 rootstock cropped more precociously when planted as two year old trees than when planted as one year old trees, even though there were no significant differences in the sizes (leader height and branch length) of the trees at the time of planting. However, the two year old trees had larger root systems at planting. As the trees aged, those planted as one year olds grew more vigorously and bore higher cumulative yields than those planted as two year olds. Annual root pruning of the trees, commencing 15 months after planting, reduced extension shoot growth, crown volume and grubbing weights (final fresh weights of scions) severely. In some seasons root pruning increased the number of spur and terminal floral buds produced and also the final sets and yield efficiencies on the treated trees. Planting trees within semi-permeable fabric membranes also reduced extension shoot growth and tree size, but less severely than the root-pruning treatment. Root restriction increased the efficiency of fruit set and yields and also improved the grades of fruits produced. Trickle irrigation treatments increased shoot growth and tree fresh weight at the time of grubbing, but had inconsistent and small effects on fruit set and yields. Interactions between tree age at the time of planting and the root manipulative treatments were significant. 相似文献
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苹果苗木类型和栽植时间对幼树生长特性的影响 总被引：1，自引：0，他引：1
【目的】为了研究不同栽植时间下不同苗木类型的生长特性,【方法】以3 a生‘长富2号’/‘M26’/八棱海棠为试材,测定3个栽植时间(2010年3月10日、4月10日和5月10日)下分枝苗、去分枝苗和单干苗生长特性相关指标。【结果】5月份栽植植株的生长势弱于3、4月栽植的植株;单干苗生长势弱于分枝苗和去分枝苗。栽植后第2年,3、4月栽植植株的株高、主干粗度显著大于5月栽植的植株。去分枝苗和单干苗株高显著大于分枝苗。3种苗木类型主干粗度依次为分枝苗>去分枝苗>单干苗,且相互差异显著。分枝苗和去分枝苗冠径显著大于单干苗。栽植后第3年,分枝苗的花芽数显著高于去分枝苗和单干苗。【结论】苹果苗木在冷藏条件下,4月栽植是可行的,本试验中3月份栽植较为适宜。分枝苗有利于促进幼树提早开花结果。 相似文献
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David J. Nowak 《Urban Forestry & Urban Greening》2012,11(4):374-382
Field data from randomly located plots in 12 cities in the United States and Canada were used to estimate the proportion of the existing tree population that was planted or occurred via natural regeneration. In addition, two cities (Baltimore and Syracuse) were recently re-sampled to estimate the proportion of newly established trees that were planted. Results for the existing tree populations reveal that, on average, about 1 in 3 trees are planted in cities. Land uses and tree species with the highest proportion of trees planted were residential (74.8 percent of trees planted) and commercial/industrial (61.2 percent) lands, and Gleditsia triacanthos (95.1 percent) and Pinus nigra (91.8 percent). The percentage of the tree population planted is greater in cities developed in grassland areas as compared to cities developed in forests and tends to increase with increased population density and percent impervious cover in cities. New tree influx rates ranged from 4.0 trees/ha/yr in Baltimore to 8.6 trees/ha/yr in Syracuse. About 1 in 20 trees (Baltimore) and 1 in 12 trees (Syracuse) were planted in newly established tree populations. In Syracuse, the recent tree influx has been dominated by Rhamnus cathartica, an exotic invasive species. Without tree planting and management, the urban forest composition in some cities will likely shift to more pioneer or invasive tree species in the near term. As these species typically are smaller and have shorter life-spans, the ability of city systems to sustain more large, long-lived tree species may require human intervention through tree planting and maintenance. Data on tree regeneration and planting proportions and rates can be used to help determine tree planting rates necessary to attain desired tree cover and species composition goals. 相似文献
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Street trees are important foundations of urban sustainability due to the ecosystem services that they provide society and the environment. However, street trees are vulnerable to vandalism and damage, especially when small, which constraints the flow of benefits they provide and also increases the costs of planting programmes. Despite being a common phenomenon, there is limited knowledge regarding the extent of vandalism and the reasons for it. Here we seek to understand the causes and extent of street tree damage in eleven small Eastern Cape (South Africa) towns and to assess the perceptions of residents and officials. The condition of newly planted street trees was assessed in each town and residents were interviewed in the two towns with the highest number of newly planted street trees. Almost half (42%) of recently planted street trees were totally snapped, ranging between 0% and 63% per town. There was no difference in the prevalence of trees being snapped between those with protective structures and those without. Each town used different structures around newly planted street trees, but in only two towns were all the structures intact. The prevalence of damage declined with increasing trunk thickness and increasing town size. According to residents, boredom, misbehaviour, lack of appreciation of trees and collection for wood were the main factors for tree vandalism by people along with damage by livestock. Ward councillors recognised the presence of vandalism, but indicated that it was not a priority topic in their ward meetings. Suggestions by residents to prevent vandalism included: planting in sensible areas, re-designing the protective structures, re-locating livestock and engendering community participation and ownership in all aspects of street tree planting. 相似文献
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Urban trees are frequently planted with their root collars and structural roots buried well below soil grade, either because of planting practices, nursery production practices, or both. These deeply planted structural roots can impair tree establishment and are thought to reduce tree growth, lifespan, and stability, although research has provided few and contradictory results on these questions to date. This study examines container-grown (55 L) Turkish hazel trees (Corylus colurna L.), planted either at grade, 15 cm below grade, or 30 cm below grade into a well-drained silt loam soil, over nearly 8 years. Five years after planting, in 2004, remediation treatments (root collar excavations) were performed on two replicates of each below-ground treatment. Subsequently, all trees were subjected to flooding stress by being irrigated to soil saturation for approximately 6 weeks. In 2006, flooding stress was repeated. Trees root systems were partially excavated in 2007, and root architecture was characterized. Deep planting did not affect trunk diameter growth over 8 years. Survival was 100% for the first 5 years; however, one 30 cm below grade tree died after flooding in 2004 and another died after the 2006 flooding. Photosynthesis was monitored during the 2004 flooding and all trees experienced decline in photosynthetic rates. There was an apparent slight delay in the decline for trees with excavated root collars and those planted at grade. Girdling roots reduced trunk taper and occurred primarily on unremediated trees planted 30 cm below grade.
Selected individual roots were excavated and followed from the root ball and were observed to gradually rise to the upper soil regions. Analysis of roots emerging from excavation trench faces indicated that vertical root distribution at approximately 1.25 m from the tree trunks was the same regardless of planting depth. Longterm consequences of planting below grade are discussed. 相似文献