梨枣枣吊生长与结果习性观察初报

枣吊是枣树结果的基本单位。我们对嫁接后的第３年幼龄枣树，结合夏季管理，对主枝上新发出的枣头和二次冬季修剪后新发的枣头，按不同的用途和要求进行了摘心，发现摘心后的枣头上及二次枝上长出的枣吊生长较快，长度和粗度均大于已形成枣股上发出的脱落性枣吊，且叶片肥...     

老枣树更新复壮技术

交城县林科所开展的“骏枣老树更新复壮技术研究”,经过几年的试验,增产效果明显。初步掌握了老枣树更新后隐芽萌发和枣头枝生育的规律,提出了根据树龄、树势,分别采用轻、中、重更新方法,为改变老枣树低产面貌提供了经验。从试验中观察到,枣树结实力以3—6年生枣股最强,比10年生以上的高3—4倍。并对更新后植株生育规律,产量的构成因子进行了统计分析,认为要提高老枣树产量,首先要提高3—6年生枣股比例。具体更新标准是:当树体内10年生枣股占枣股量35—40％左右、树龄在50—100年生的枣树,宜采用轻更新;树体内10年生枣股占枣     

幼龄灵武长枣摘心试验初报

灵武长枣是宁夏地方乡土良种。截止2005年底,全市有4年生以下灵武长枣幼龄园5.16万亩。怎样使幼龄枣树实现早果早产是生产中亟待解决的难题。笔者通过试验得出,对灵武长枣幼龄枣树采取枣头摘心和二次枝摘心,可促进二次枝增粗,提高座果率。     

阜平大枣树体状况与坐果的关系

通过对阜平大枣丰产园不同修剪程度树体状况与枣树结果关系的调查表明，阜平大枣丰产园叶系数以２．４－２．５为宜，３－１１ａ生枣股坐果率最高，２－１０ａ生枣股上着生的枣果单果重较大。同时将阜平大枣结果母枝分为１－２ａ生过度结果母枝，３－１０ａ生旺盛结果母枝，１１ａ生以衰老结果母枝。过渡结果母枝枣果成熟期晚，旺盛结果母枝枣果成熟期适中，衰老结果母枝枣果成熟期最早。通过分析提出，阜平大枣的理化修剪指标为每平     

灰枣枣树枣股生育规律的初步观察

本文探讨了枣树研究中尚未涉及的问题———枣股的生长发育规律。作者通过观察 ,发现影响枣股生长发育的主导因子———股龄等因子及其间的相互关系 ;首次提出枣股龄级的划分依据和标准 ,及对结果的影响 ,为枣树丰产、稳产栽培提供了科学依据。     

幼龄枣树枣头强化摘心技术研究

对幼龄枣树枣头强化摘心技术研究表明 ,摘心能提高枣树座果率 ,对新生枣头 ,5月中旬到 6月上旬摘心 ,当年可形成产量 ;枣头摘心除去顶端优势 ,导致二次枝粗壮 ,脱落性枝木质化。一般枣木质化枣吊结果数是正常枣吊结果数的 10倍左右 ,半木质化枣吊结果数是正常枣吊结果数的 5倍左右。     

红枣枣股的培育方法探讨

枣股是枣树上最基本的结果部位,是枣树上特有的一种缩短型结果母枝。保持一定数量壮龄枣股和尽量延长壮龄枣股的结果年限,是保证枣树连年丰产稳产的关键。     

绿盲蝽成虫对枣树叶片、花蕾、幼果危害能力测定

为进一步了解绿盲蝽对枣树危害的严重性,在枣产区沧县高川乡朴寺村3 a生金丝小枣苗圃对其成虫危害枣叶、花蕾、幼果的能力进行了测定,结果为:绿盲蝽成虫每头每天平均危害枣叶2.46片,花蕾2.74个,幼果1.59个。     

枣树花期管理

同其它水果树相比 ,枣树花期的特点是 :花芽分化与抽生结果枝同步进行 ,花期长、花量大 ;落果重 ,座果率低。因此 ,做好枣树花期管理 ,提高座果率 ,减少落果 ,是枣树丰产的一项重要措施。枣树花期管理 ,除做好枣园土、肥、水管理外 ,还必须做好以下工作。1　调节树体营养(1 )修剪　枣树花期应及时疏除无利用价值的新枣头 ,并及时疏除结果枝基部萌生的徒长枝 ,交叉枝和重迭枝。对枣股上萌生的新枣头 (足芽 )从基部 3 cm处剪除。对萌发可利用的新枣头 ,除缓放的外 ,及时根据生长势、生长位置及空间大小摘心。一般弱枝轻摘心 ,强枝重摘心 ;空间…     

石楼县枣树种质资源调查研究

从枣树植物学特征、生长结果习性、果实特性、物候期及立地条件等方面对石楼县枣树资源进行了调查研究,收集保存了枝、叶、花、果实标本和树体特征、结果性状照片,初步查清了该县现有枣树品种19个,其中主栽品种有木枣、灰枣、团枣、芽枣和脆枣。     

云南甜龙竹矮化密植技术及其经济效益分析

在新平县进行云南甜龙竹矮化密植试验：利用定植当年幼林林中空地进行竹农间作;通过合理留笋齐竹,留笋长成的竹秆,实施竹秆矮化控制处理,促发竹主枝,作为空中诱根育苗的种源培育竹苗;采收所有除留笋养母竹后的竹笋出售;竹林郁闭后,逐年间移竹丛分蔸苗处理,得到竹子蔸苗．定植后5年内每年可得经济收入35047元／hm^2．     

毛竹主秆人工造型研究

在毛竹竹笋长成新竹的过程中,利用正方型的铁制模具套住笋体,强制毛竹主秆形状由圆形变方形。试验结果表明：竹笋高度超出模具5cm以上、竹笋粗度周长等于或略小于模具周长的竹笋,套上模具后竹笋既可成活,毛竹主秆又可形成方型;竹笋粗度周长大于模具周长的,上模后须适时对模具放松竹笋才能成活成型;套模后成活成型的新竹胸围、枝下高、全竹高只有对照的80％、53．8％、56．4％。研究表明在毛竹竹笋长成新竹的过程中,其主秆形状有可塑性,但对新竹的胸围、枝下高、全竹高生长有严重影响,会导致毛竹主秆矮化。     

Within-crown structural variability of dwarfed mature Abies mariesii in snowy subalpine parkland in central Japan

We investigated mature dwarf Abies mariesii trees growing in conifer thicket–meadow parklands on a snowy subalpine plateau, where these dwarf trees are buried in the accumulated snow in winter. We focused on structural variation in the needles, shoots, and branchlets within different crown positions (leader crown vs lower crown) of the dwarf trees. In the leader crown, which appears above the snow surface earlier than the lower crown, current-year shoots and branchlets had greater total biomass, and foliage was more closely packed along the stem axis than in the lower crown, whereas current-year shoots in the leader crown had a lower needle mass ratio than in the lower crown. These results suggest that current-year shoots and branchlets in the leader crown have a specific structure that allows them to harvest more light, although construction and maintenance costs would be higher. In contrast, the structural characteristics of current-year shoots and branchlets in the lower crown efficiently concentrate incoming light by avoiding mutual shading within foliage, thus leading to increased biomass of photosynthetic needles within shoot and branchlet biomass. Such within-crown variability at various hierarchical levels from needles to branches in mature, but very dwarf, A. mariesii trees maintains the crown and allows survival within conifer clumps in areas of subalpine parklands that receive heavy snowfall.     

An in vitro method for screening Colletotrichum gloeosporioides as a biological control agent for western hemlock dwarf mistletoe

An in vitro system using detached western hemlock branches infected with dwarf mistletoe was developed to screen the virulence of five isolates of Colletotrichum gloeosporioides, a hyperparasite of dwarf mistletoe shoots and berries. Detached branches infected with dwarf mistletoe were placed in nutrient‐saturated rock‐wool blocks and mistletoe shoots were inoculated with a conidial suspension of C. gloeosporioides. One month after inoculation, lesions on mistletoe stems and berries were well developed. Infection levels for individual isolates varied from 40% to 60% of shoots and 60% to 80% of berries. Significant differences were found between the isolates and control (p = 0.02 and 0.001, respectively) while no differences were noted between the isolates for both the shoots and berries. Parallel inoculation of mistletoe shoots detached from hemlock branches on moist filter paper and in rock‐wool blocks failed because these shoots deteriorated rapidly, fragmenting into segments within a week. This in vitro test may provide an alternative method for rapid screening of potentially virulent C. gloeosporioides isolates.     

Relationships between the number of dwarf shoots of<Emphasis Type="Italic"> Larix decidua</Emphasis> Mill. damaged by different insect species in the Ojców National Park in southern Poland

A study was conducted on the interrelationships between the number of dwarf shoots of Larix decidua Mill. damaged by insects: Adelges laricis Vall. Coleophora laricella Hbn., Spilonota laricana Hein. and Dasineura kellneri (Hensch.). The study made use of dwarf shoots collected at three sites in the Ojców National Park, southern Poland during 2002–2003. A total of 240 branches with 19,239 dwarf shoots, collected from 60 larches were designated to the study. The data obtained were subjected to statistical analysis using the Spearman rank correlation coefficient and the Students t-test at the 0.05 level. No unequivocal correlation was found between the relationships.     

厚朴年生育规律的研究

厚朴是我国特有、珍稀药用树种。厚朴枝、叶生长的特殊性是构成厚朴特有生长规律的生理基础;“厚朴叶片簇生枝基” 的发现,纠正了自厚朴新种发表以来,近80年的错误记载;厚朴年生育规律主要决定于其生物学特性,同时受气候因素影响.     

苹果抗寒矮化砧木71-3-150茎尖培养快繁体系建立

以苹果抗寒矮化砧木71-3-150的茎尖为外植体,通过研究培养基中不同植物生长调节剂配比对芽苗诱导、增殖和生根的影响,筛选出适合71-3-150砧木茎尖组培快繁的培养基配方。结果表明,以MS为基本培养基,附加蔗糖30 g／L、琼脂6 g／L,适宜启动培养的植物生长调节剂为6-BA 1.0 mg／L＋NAA 0.05 mg／L;适宜增殖培养的植物生长调节剂为6-BA 1.0 mg／L＋NAA 0.05 mg／L,增殖系数可达到每4周4.75倍。以1／2MS （蔗糖15 g／L,琼脂6 g／L）为基本培养基,适宜组培苗生根的植物生长调节剂为IAA 1.0 mg／L＋IBA 0.6 mg／L,生根率达100％,每株苗平均生根9.6条,移栽成活率达90％以上。     

Variation in rooting behavior of stem cuttings in relation to their origin in Taxus wallichiana Zucc.

The present study investigates optimal conditions for the vegetative propagation of Himalayan yew Taxus wallichiana Zucc., an important medicinal tree, during spring. Effect of four treatments: (a) sex of donor plant (male and female), (b) age/type of shoot (1, 2, 3 year old, long and dwarf shoots), (c) auxin treatment (IBA and NAA at 0, 0.5, 1.25, 5.0 & 50.0 mM) and (d) rooting environment (raised beds/polythene bags) on percentage rooting in stem cuttings was studied. Randomized complete block (RBD) designs were used for experimentation. Rooting ability of cuttings was significantly influenced by all these treatments. The overall rooting response was higher in long shoot cuttings taken from female tree. Age of shoot also influenced the rooting response and was highest in 1 year old long shoot cuttings of female tree. Exogenous application of auxin, α-naphthalene acetic acid (NAA) and indole-3 butyric acid (IBA), had significant positive effect on the percentage rooting. IBA significantly enhanced the rooting percentage in 1 year old long and dwarf shoots at lower doses and 2 and 3 year old long shoots from female tree at higher doses. Maximum percent rooting (90% ± 2.8) was obtained with interactive effect of 0.5 mM, NAA (22 h) × 1 year old long shoot from female tree; followed by the interactive effect of 50 mM IBA (5 s) × 3 year old long shoot from female tree (83% ± 4.1). Cuttings planted in soil: sand medium in polythene bags showed earlier rooting response (12 weeks) than cuttings planted in raised nursery beds (24 weeks). Overall, the findings of this study suggest that 0.5 mM IBA treatment is suitable for enhancing adventitious rooting in 1 year old long and dwarf shoots of male and female trees. IBA at higher doses is suitable for enhancing the rooting percentage of 2 and 3 year old long shoots from female tree. This study provides a significant lead towards the development of a simple and inexpensive technique for large scale propagation, aforestation of elite genotypes and raising of bush type plantation under ex-situ conditions.     

SH系砧木及对应中间砧红富士苹果枝条水分输导阻力研究

为进一步揭示砧木的矮化机理 ,以SH系矮化砧木及相应中间砧红富士苹果为试材 ,在生长季测定砧木枝条及嫁接部位的水分输导阻力。结果表明 ,SH系砧木枝条及嫁接部位的水分输导阻力 ,随砧木矮化程度的升高而增大 ,表明水分输导阻力的增加 ,是导致嫁接树矮化的原因之一。     

落矶山圆柏幼树生长节律研究

落矶山圆柏直径生长期270 d,树高生长期240 d,生长盛期在4月,其次为5、6月,与春梢、二、三梢相对应,是高生长的主要季节。在生产中应根据上述的生长规律,合理安排松土、除草和施肥等措施。