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核桃栽植管护的关键技术 总被引：1，自引：0，他引：1
1栽植
1．1适地适树：优质核桃分早实类型和晚实类型，早实核桃如西岭、辽1、辽4等，要求土层厚度在1米以上，并且具备灌溉条件；晚实核桃如清香等，也可以在土壤比较瘠薄、灌溉条件较差的立地条件下生长结果，但在好的条件下，结果和生长会更好。 相似文献
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以罗甸小米核桃苗木为试验材料,采用称取质量控制土壤含水量的方法,设置对照(CK)、轻度水分胁迫(W1)、中度水分胁迫(W2)和重度水分胁迫(W3)4个不同处理,研究罗甸小米核桃幼苗的生长特性。结果表明:水分胁迫下,罗甸小米核桃的生长受到抑制,苗高、地径、叶面积、生物量增长量都呈现出减少的趋势,并且随着水分胁迫强度和胁迫周期的增加而下降。 相似文献
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目前云南大面积栽培的核桃中，树体长势好，生长旺盛，但群体混杂，种性退化严重，出现品种差、产量低、品质劣的问题。采用高接改优方法，早实核桃品种高接后1～2a结果，晚实品种2～3a结果，可显著提高产量和品质。 相似文献
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早实核桃新品种丰产栽培技术 总被引：2，自引：0，他引：2
早实核桃结果早，产量高，营养消耗多，只有在园址选择适宜和管理水平较高的情况下，才能表现出早实、丰产、优质的特性。现将核桃早实密植丰产栽技术简介如下。 相似文献
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扶风早实核桃枝条短截试验初报 总被引：4，自引：4，他引：4
扶风早实核桃由于结实早，结果多，分枝多，养分过度消耗，容易引起树势过早衰弱。通过进行顶梢、秋梢中部、春秋梢交界处、春梢中部短截处理，得出这些短截方法对新生枝条的数量、长度、粗度、时面积、副梢生长和剪口下枝条桔死长度都产生了不同程度的影响。从春梢中部短截修剪，能够刺激扶风早实核桃植株的生长，对增强树势和抑制枝条桔死有明显作用。 相似文献
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核桃嫁接繁殖及丰产栽培技术 总被引：6，自引：0，他引：6
核桃（Jualans regia）属胡桃科油料干果乔木树种，分布较广。核桃的繁殖分种子繁殖和嫁接繁殖两种。根据结实早晚分为早实核桃和晚实核桃，依照果壳的薄厚分为纸皮、薄壳、中壳和厚壳。核桃以果壳薄而美观、核大、易取仁、种仁含油率高（在60％以上）、抗逆性强、早结实、早熟丰产为佳品，如辽核1号、辽核2号、中林5号、元丰、鲁光、温185，都具有良好的市场前景，是核桃产业开发的优良品种。现将其栽培技术介绍如下，以便在生产中应用。 相似文献
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Responses of the endemic leguminous shrub Bauhinia faberi var. microphylla, to various soil water supply regimes were studied in order to assess water stress tolerance of seedlings. Two-month-old
seedlings were grown under water supply regimes of 100, 80, 60, 40, and 20% water field capacity (FC), respectively, in a
temperature and light-controlled greenhouse. Plant height and leaf number were measured monthly over a 4-month period, while
water use (WU), water-use efficiency (WUE), leaf relative water content (RWC), biomass production and its partitioning were
recorded at the end of the experiment. Seedlings exhibited the greatest biomass production, height, basal diameter, branch
number, leaf number, and leaf area when soil content was at 100% FC, and slightly declined at 80% FC. These parameters declined
significantly under 60% FC water supply, and severely reduced under 40 and 20% FC. RWC, WU and WUE decreased, while the ratio
of root mass to stem mass (R:S) increased in response to decreasing water supply. Water stress caused leaf shedding, but not
plant death. The results demonstrated that B. faberi var. microphylla seedlings could tolerate drought by reducing branching and leaf area while maintaining a high R:S ratio. However, low dry
mass and WUE at 40 and 20% FC suggested that the seedlings did not produce significant biomass under prolonged severe water
deficit. Therefore, before introducing B. faberi var. microphylla in vegetation restoration efforts, water supply above 40% FC is recommended for seedlings to maintain growth. 相似文献
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To alleviate the combined effects of water and heat stress prevailing in drylands, the choice and introduction of appropriate plant species to these conditions is essential for the success of planting in rehabilitation projects. The argan tree (Argania spinosa) is a vigorous plant, admirably adapted to dry climates, with indisputable physiological and ecological characteristics that make of this tree an ideal plant to fight against erosion and desertification process, which seriously threaten arid lands. However, the geographical origin of seeds/seedlings represents a determining factor. In this context, we investigated the morphological responses of growth in two provenances of argan, the provenance of Tindouf ‘PT’ from Algeria and that of Agadir ‘PA’ from Morocco; under water stress conditions. The experiment attempts to evaluate the level of drought tolerance of these two provenances for selecting the planting material that copes and adapts better to hot arid lands. Argan seedlings of both provenances (PA and PT) were submitted to a water stress gradient (75, 40, 20, and 10% of field capacity), then morphological parameters (shoot height, number of leaves, number of spines, root collar diameter, length of taproot) were measured after 3, 6, 9 and 12 months of growth. All variables of morphological growth varied significantly (P < 0.001) between water stress levels, seed geographical provenances and seedling growth ages. The overall of results concerning morphological parameters indicated that the increase of water stress induced in both argan provenances: a decrease in shoot height associated with an increase in length of taproot that resulted in the reduction of leaf numbers and radial growth but the increase the number of spines. The argan plantlets of Agadir have completely failed to tolerate water stress of 10% FC. Under water stress (40, 20, 10% FC), argan seedlings of Tindouf revealed higher growth results than those of Agadir. PT seedlings offset the water deficit by root elongation to ensure growth of the various components of the aerial part. PT seedlings were more resilient to drought stress as compared to those of PA. The highest growth results were obtained with 40% FC in PT seedlings, and with 75% FC among PA seedlings. It is recommended to use the PT seeds in planting projects under drought conditions, while PA seeds are more suitable under conditions of non-water deficit. 相似文献
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The adaptation responses to different water conditions and the drought tolerance of Sophora davidii seedlings were assessed in a greenhouse experiment. Two-month-old seedlings were subjected to the following water supplies
for 95 days: 100, 80, 60, 40 and 20% of field water capacity. The seedlings at 100% FC had the greatest productivity, height,
basal diameter, branch number, leaf number and leaf area. Water supply <80% FC was the threshold of drought-initiated negative
effects on seedling growth, yield and physiological processes; these parameters were severely reduced at 20% FC, however,
there was no plant death during the experiment. Moreover, water stress decreased leaf relative water content, specific leaf
area, leaf area ratio, and water-use efficiency (WUE), whereas it increased the biomass allocation to roots, which resulted
in a higher root:stem mass ratio under drought. The S. davidii seedlings tolerated drought by maintaining high leaf relative water content and by reducing branching and leaf expansion.
However, low productivity and WUE at 20% FC suggested that seedlings did not produce high biomass under severe drought. Therefore,
prior to introducing S. davidii in forestation efforts, a water supply >40% FC is recommended for seedlings to maintain growth and productivity. These results
provide insights into limitations and opportunities for establishment of S. davidii in arid regions. 相似文献
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Seedlings of Betula pendula Roth were grown with their root systems separated between two soil compartments. Four treatments were imposed: (i) adequate irrigation in both compartments (WW, controls); (ii) adequate irrigation in one compartment and drought in the other compartment (WD); (iii) drought in both compartments (DD); and (iv) half of the root system severed and the remainder kept well-watered (root excision, RE). Predawn leaf water potential, stomatal conductance, soil-to-leaf specific hydraulic conductance, and root and leaf growth decreased in DD-treated seedlings, which also displayed severe leaf shedding (30% loss in leaf area). The DD treatment also resulted in increased concentrations of abscisic acid (ABA) and its glucose ester in the xylem sap of roots and shoots compared to concentrations in control seedlings (about 200 versus 20 nM). Despite the difference in xylem sap concentrations, total ABA flux to the shoots was similar in the two treatments (1-2 pmol ABA m(-2) leaf area s(-1)) as a result of reduced transpiration in the DD-treated seedlings. Compared with root growth in control plants, root growth increased in the RE-treated plants and decreased in the drying compartment of the WD treatment; however, the RE and WD treatments only slightly reduced leaf expansion, and had no detectable effects on shoot water relations or ABA concentrations of the root and shoot xylem sap. We conclude that short-term soil water depletion affecting only 50% of the root system does not cause a measurable stress response in birch shoots, despite root growth cessation in the fraction of drying soil. 相似文献
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Effects of soil water availability on seedling growth, dry matter production and allocation were determined for Gympie (humid coastal) and Hungry Hills (dry inland) provenances of Eucalyptus cloeziana F. Muell. and for E. argophloia Blakely (dry inland) species. Seven-month-old seedlings were subjected to well-watered (100% field capacity, FC), moderate (70% FC) and severe (50% FC) soil water regimes in a glasshouse environment for 14 wk. There were significant differences in seedling growth, biomass production and allocation patterns between species. E. argophloia produced twice as much biomass at 100% FC, and more than three times as much at 70% and 50% FC than did either E. cloeziana provenance. Although the humid provenance of E. cloeziana had a greater leaf area at 100% FC conditions than did the dry provenance, total biomass production did not differ significantly. Both E. cloeziana provenances were highly sensitive to water deficits. E. argophloia allocated 10% more biomass to roots than did E. cloeziana. Allometric analyses indicated that relative biomass allocation patterns were significantly affected by genotype but not by soil water availability. These results have implications for taxon selection for cultivation in humid and subhumid regions. 相似文献
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Effects of soil moisture and light intensity on ecophysiological characteristics of Amorpha fruticosa seedlings 总被引：1，自引：0，他引：1
We investigated the combined effects of soil moisture and light intensity on the growth, development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings. Soil moisture and light intensity influenced the ecophysiological characteristics of Amorpha fruticosa seedlings. Soil moisture resulted in the decreases of growth rate, individual size, net photosynthetic rate, transpiration rate, leaf water loss rate (WLR), and biomass accumulation of plant parts, and led to increased leaf water saturation deficit (WSD). Under water stress, more photosynthetic products were allocated to root growth. With decreasing light intensity, net photosynthetic rate, transpiration rate, chla/b, water saturation deficit, water use efficiency, water loss rate and biomass accumulation declined, while Chla, Chlb, Chla+b and carotenoids (Car) increased and more photosynthetic products were allocated to stem and leaf growth. Maximum growth vigor, net photosynthetic rate and total biomass accumulation in Amorpha fruticosa seedlings was recorded at 75 80% soil water-holding capacity and 100% light density in greenhouse environments. 相似文献
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Bilas Singh 《Journal of Sustainable Forestry》2013,32(6):480-495
We assessed interactive effects of varying levels of applied phosphorus fertilizer and water stress on growth, productivity, and mineral accumulation in container-grown Dalbergia sissoo L. seedlings. Height, collar diameter, leaf size and area, root volume and total biomass were reduced, and dry matter allocation to root was increased with increasing levels of soil water stress. The reduction was >32% in growth, >50% in leaf, and >77% in biomass when seedlings were grown with <50% of soil field capacity. Phosphorus application at the level of 10 mg kg?1 soil enhanced stems and leaf biomass and nutrient accumulation at all irrigation levels, and thus tolerance to drought. Phosphorus responses to growth and biomass production increased with irrigation levels. Thus, 20 mg P kg?1 soil is beneficial at sufficient soil water availability and a lower dose (i.e., 10 mg P kg?1) is recommended under high soil water stress conditions to benefit growth and productivity of D. sissoo. 相似文献
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杉木营养平衡与苗木干物质的分配关系 总被引：6，自引：3，他引：6
详细研究了不同营养 (N、P、NP)条件下杉木苗木干物质在根冠的分配规律 ,结果表明 ,不同的营养条件可导致苗木光合产物在根冠发生明显再分配 ,苗木的营养状态和根冠干物质分配的关系规律可应用异速生长模型y =axk 来描述和刻划。基于营养与光合产物在根冠的再分配规律及异速生长模型参数k值对营养胁迫反应的敏感性变化规律 ,提出了新的营养平衡理论和营养诊断方法 (称之为苗木群体营养诊断法 )。营养诊断法则为 :(1)在某一营养条件下 ,如果苗木异速生长模型参数k <1时 ,表明根系相对生长速率高于冠层相对生长速率 ,苗木处于营养亏缺状态 ;(2 )当k >1时 ,表明苗木冠层相对生长速率高于根系 ,苗木处于营养过剩状态 ,一般在自然条件下 ,k >1是不会出现的 ;(3)当k =1时 ,表明根系和冠层相对生长速率相等 ,苗木处于营养平衡状态。根据新的营养诊断方法 ,制定了杉木叶片和土壤营养诊断标准 ,并通过大量的杉木幼、中、近熟林施肥试验结果验证了营养平衡理论的正确性。 相似文献
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在温室内用盆栽法栽植了1年生茶条槭、山梨和山桃苗木,并采用4种土壤水分处理,土壤相对含水量分别为75.0%、61.1%、46.4%和35.4%。结果表明:随土壤含水量降低,3树种苗木净光合速率,蒸腾速率和气孔导度均下降,土壤含水量最低时,茶条槭苗木各生理指标降低幅度最大,山梨和山桃次之。茶条槭和山梨水分利用效率随土壤含水量的减少呈降低趋势,山桃水分利用效率呈升高趋势。水分胁迫下,3树种苗木根分配生物量显著增加。茶条槭在水分胁迫下,根冠比增加幅度最大,山梨次之,山桃最小。此外,茶条槭叶形态可塑性强,随土壤含水量降低,茶条槭单叶叶面积和总叶面积显著减小,叶厚度增加。山梨和山桃在水分胁迫下单叶叶面积及总叶面积无显著变化。综合3树种苗木在水分胁迫下的生理和形态指标及生物量分配的变化,茶条槭对水分胁迫的适应能力强于山桃和山梨。表3参31。 相似文献