不同疏剪强度对油茶新梢生长和矿质元素分配的影响

为了探明油茶树体对疏剪的反应,为油茶的科学修剪提供理论依据和指导,研究了不同疏剪强度处理对油茶新梢生长及矿质元素分配的影响。结果表明,不同强度的疏剪显著影响了油茶新梢的发枝量,疏剪强度越大,发枝量越小;疏剪处理显著提高了新梢的长度,改变了不同长度新梢的比例,高强度的疏剪提高了长梢(>10cm)的比例,降低了短梢(<5cm)比例;此外,疏剪处理改变了不同组织器官矿质元素的含量和分配,一定程度上提高了新梢和枝干间氮、磷、钾元素含量的比值;1/4强度疏剪对促进新梢萌发、平衡长短梢比例、改善新梢矿质元素含量效果最佳。     

Photosynthetic response to green crown pruning in young plantation-grown Eucalyptus pilularis and E. cloeziana

The loss of foliage through pruning of live branches may reduce tree growth or it may be compensated by photosynthetic up-regulation of the remaining crown. Here, the changes in light-saturated photosynthesis following pruning to remove 50% of green crown length were examined in 4-year-old Eucalyptus pilularis Sm. and Eucalyptus cloeziana F. Muell. trees. The objectives of the study were to: (1) compare leaf-level physiological (light-saturated photosynthesis (A_max), stomatal conductance (g), transpiration (T), dark respiration (R_d), quantum yield (Φ), light compensation point (Γ), water-use efficiency (WUE), nitrogen-use efficiency (NUE)) traits in species with contrasting crown dynamics and structure, (2) examine the effect of crown position on these traits, and (3) examine the effect of pruning on A_max, g, T, WUE, NUE, leaf N and P concentrations and specific leaf area (SLA). Prior to pruning there were no differences in R_d, Γ and Φ between E. pilularis and E. cloeziana but differences in A_max, T, g, leaf N, leaf P, WUE, NUE and SLA. Whereas the rate of physiological processes (A_max, T, and g) and leaf N and P concentrations increased with crown height, R_d, Γ, Φ and SLA declined along this vertical gradient, except in the upper crown of E. cloeziana where A_max, T and g were not different to the lower crown. No up-regulation of photosynthesis or changes in leaf physiology occurred between 6 and 13 months after pruning in either species. The results provide an important basis for modelling pruning effects in process-based tree growth models.     

木荷优质干材培育修枝技术的研究

对木荷林培育优质干材的修枝技术及效应进行了分析研究。结果表明:木荷早期较耐阴,萌芽性强,易发生副梢,分枝较密集,自然整枝能力差。作为用材林培育,应该采取适当的修枝措施。修枝适宜在5 a生左右进行,在休眠季采取中度修枝(修去冠长的2/6)。合理的修枝,有利于树高、树径和立木材积的生长,能够提高其干材质量。     

架式和整枝方式对日光温室葡萄新梢生长的影响

为了研究修剪技术对温室葡萄新梢生长的影响,本试验通过对温室葡萄的不同品种、以及同一品种在不同整枝方式下和不同架式下的枝条生长情况进行了研究,结果表明,①在同一(FI形)整枝方式下,奥古斯特、无核早红、无核白鸡心的新梢生长量极显著高于粉红亚都蜜、早黑宝、京秀、优无核;②FI形整枝方式比F形、扇形更有效控制新梢的徒长;③棚架和篱改棚能明显抑制葡萄新梢徒长。     

整枝方式及留果数对甜瓜叶片发育和果实生产的影响

[目的]为甜瓜的合理整枝提供依据。[方法]以黄河蜜、Tan Dew和玉金香3个品种为材料,研究了2蔓整枝和3蔓整枝对甜瓜叶面积、产量及品质的影响。[结果]3个甜瓜品种在伸蔓期、黄河蜜在开花坐果期,3蔓整枝的单株叶数和叶面积显著多于2蔓整枝。3蔓整枝的黄河蜜的单果重、单株产量,Tam Dew的单果重、单株产量、小区产量,玉金香的单株果数、单株产量、小区产量显著高于2蔓整枝。留2果的黄河蜜、TamDew的单果重、肉厚、糖含量均显著小于留1果的。玉金香留3果的单果重、肉厚、糖含量显著小于留2果的。[结论]黄河蜜2蔓整枝留1果,TanDew3蔓整枝留1果,玉金香2蔓整枝和3蔓整枝留2果较好。     

弱势苹果树不同程度冬季修剪试验

连续3年对弱势苹果树进行研究,结果表明,采用重剪、回缩更新复壮的修剪方法后,树体通风透光性能改善,叶绿素含量和比叶重提高,光合作用增强,果实着色好,可溶性固形物含量和硬度也得到了提高,改善了果实品质,同时还增加了果实产量。     

不同修剪水平对葡萄叶幕光照微区气候和水分关系的影响

本实验在法国波尔多的生态条件下，从叶幕光照微区气候和植物水分关系的角度，设计比较了四种植株芽眼负载量（修剪水平）和不同的修剪方式后指出，轻修剪水平（重负荷）的葡萄植株，由于生长的“自动调节”，整个叶幕水平上光照微区气候没有出现恶化现象。但是果际的郁蔽也许是造成物质代谢不良的重要原因之一。在水分关系方面，轻修剪水平植株整个叶幕前半天的蒸腾作用较强，但是以较剧烈的“午间低谷”和整个下午的低水平作为代价；伴随着这个现象的是午后叶幕气孔导性和叶面水势的较低水平。轻修剪水平对植株叶幕光照微区气候和水分关系影响的机理以及对葡萄果实品质形成的作用在本文中作了讨论。     

Sooty canker,a destructive disease of banyan (Ficus benghalensis L.) trees in landscapes of Kish Island (Iran)

Ficus benghalensis L (banyan tree) has been planted as ornamental tree in parks, landscapes as well as along roads and streets in many southern cities of Iran. During field surveys conducted in Kish Island (Hormozgān province) an unusual decline was noticed on F. benghalensis. Affected trees exhibited bark necrosis, peeled off bark and cankers on branches and aerial roots, yellowing and defoliation, branch dieback and eventually death. A black sooty mass of fungal spores under the bark as well as wood discoloration in cross sections were also observed on infected parts of trees and pruning wood debris. Samples were collected from all affected parts of trees showing disease symptoms, pruning wood debris as well as rove arthropods in close proximity to the trees for the presence of fungal inoculum. In this study 239 Botryosphaeriaceae-like isolates were obtained from discoloured wood tissues, pruning wood debris and from the bodies of collected arthropods. Based on morphological characteristics and DNA sequence data of ITS and tef-1α gene regions, isolates were identified as Lasiodiplodia theobromae and Neoscytalidium dimidiatum. Pathogenicity of both species was performed on the branches of banyan trees and L. theobromae was more virulent, based on the length of necrotic lesions in the wood, than those of N. dimidiatum. This study is the first report of N. dimidiatum associated with sooty canker and dieback of F. benghalensis worldwide. Our study showed for the first time that L. theobromae and N. dimidiatum can also be associated with some arthropods. Our outcomes can improve the management strategies of trunk diseases caused by Botryosphaeriaceae species on ornamental trees in landscapes.     

桤木采穗圃无性系树体管理试验

通过对桤木无性系采穗圃植株主干定干高度、枝条修剪强度等试验研究表明：无性系植株的嫩枝总芽数与无性系植株定干高度及枝条修剪强度等密切相关.建立桤木无性系采穗圃,无性系植株定干高度以90 cm为宜,且无性系枝条宜采用轻短截,这样既可提高无性系植株嫩枝总芽数,又扩大树冠,增强树势,保证采穗圃插穗的高产稳产.     

修剪强度对不同密度板栗叶片质量与光合特征的影响1）

以13年生‘3113’板栗为试验对象,在河北省迁西县板栗种植园内两种主栽密度下（密度Ⅰ,株行距3 m×4 m;密度Ⅱ,株行距4 m×6 m）分别进行3种修剪强度试验,分别是P1、P2、P3,每平米树冠投影面积留母枝数为8、10、12个;测定了板栗冠层不同部位叶片的叶绿素质量分数、比叶质量和光合特征（净光合速率、蒸腾速率和瞬时水分利用效率）。结果表明：两密度中冠层各部位叶绿素质量分数均随着修剪强度的增加而降低;由小到大的顺序均表现为P1、P2、P3。密度Ⅰ中比叶质量、净光合速率与蒸腾速率均随着修剪强度的增加而增加,由大到小的顺序为P1、P2、P3;密度Ⅱ冠层各部位比叶质量最高值均出现在P2中,达到了140．55 g· m－2,在冠层上部P2净光合速率和蒸腾速率显著高于P1、P3。瞬时水分利用效率差异较小,密度Ⅰ中P1冠层中部与内膛最低,其他部位无差异;密度Ⅱ中,除内膛无差异外,P3显著高于其他两个处理。