竹柳覆盖地膜扦插育苗技术

竹柳为杨柳科(Salicaceae)柳属植物,落叶乔木,覆地膜扦插育苗效果好。文章从整地施肥、种条采集与插穗处理、扦插、苗期管理、病虫害防治方面总结了竹柳覆膜扦插育苗技术。     

竹柳持续淹水后的生长状况及耐水性调查研究

本文研究了江洲地、湖滩地当年新造竹柳成活率、生长量、病虫害等情况。结果表明,竹柳在持续2～3月的水淹情况下,对造林成活率影响不大,淹水过顶高度50cm以下、持续时间20d以内,成活率仍可达到造林验收合格标准;淹水过顶50cm以上,成活率将难以保证。淹水高度在林冠层以下,即离地面150cm,林木光合作用能正常进行,对竹柳的高径生长影响不大。林地淹水高度越高、淹水持续时间越长,其高、径生长量越小。     

雪柳的引种栽培

雪柳既具有很高的观赏和商业价值,又具有很强的生存适应能力,其在园林绿化中的作用已日益明显,但东北地区将雪柳作为绿化树种还比较少见。介绍了雪柳的属性特点、生长环境及其用途,提出了"南柳北移"的设想,并对其进行了简要分析。     

柳树癌肿病初步研究

柳树癌肿病是一种新的危险性枝干病害,典型症状是溃疡部凹陷,本质部裸露,溃疡斑边缘隆起肿大,使病部呈梭形,后期凹陷部长出桔红色于实体,子实体常呈同心环状排列。经分离鉴定,病原为瘤座孢属的真菌(Tubereularia sp.).在河北廊坊地区,4月底至5月初开始发病;病菌可从各种伤口侵染寄主,病害潜育期约26d.病害发生与林龄,立地条件、经营水平有关。     

西宁地区柳树细菌性枯萎病的研究

近年来西宁市行道树柳树出现大量死亡 ,均由柳欧文氏杆菌 Erwinia salicia危害所致。该病在西宁市 4～ 10月持续发病 ,不断引起树木死亡。在防治方法上 ,应加强养护管理 ,提高树木的抗病能力 ,及时清理病枝、病株 ,以控制病害蔓延     

保水剂载内吸农药防治杨十星吉丁初报

用 4 0 %氧化乐果乳油与 XJ- X型保水剂原粉按 1∶ 4比例混配 ,树干刮皮涂药或打孔注药防治杨十星吉丁 Melanophila decastigma Fabricius,防效可达 95%以上。     

覆膜对滨海盐渍土水盐分布和竹柳生长的影响

通过野外定点监测试验研究了覆膜对滨海盐渍土水盐分布和竹柳生长的影响。结果表明：与不覆膜对照相比,覆膜处理土壤含水量和土壤含盐量都有减少的趋势,土壤含盐量减少的趋势更加明显,但两种处理相同土层土壤含水量和土壤含盐量都无显著差异（P〉0．05）。对照和覆膜的土壤含水量和土壤含盐量在土壤剖面上的分布规律也基本一致,土壤含盐量随着土壤深度的增加而减少,与土壤含水量分布的趋势相反。覆膜明显促进了竹柳茎的生长,而对竹柳的主枝数和主枝生长无明显影响,覆膜处理显著增加了竹柳的侧枝数和侧枝生长量。     

Mendelian inheritance of rust resistance to Melampsora larici‐epitea in crosses between Salix sachalinensis and S. viminalis

Two F₁, two F₂ and two backcross (BC) full‐sib families of Salix sachalinensis × S. viminalis were tested for resistance to two pathotypes of Melampsora larici‐epitea in leaf‐disc inoculation experiments. Two single‐pustule isolates, VM and ST, belonging to pathotypes LET1 and LET5, respectively, were used in the tests. Disease was scored based on the number of uredinia, uredinial diameter and inoculum densities. Both F₁ families were completely resistant to both VM and ST. Resistance to VM segregated at a 9:6:1 ratio in the F₂ families and at a 1:2:1 ratio in the BC families, suggesting that two independently segregating genes controlled rust resistance, with resistance dominant over susceptibility. This also indicates incomplete dominance of the resistance alleles over the susceptibility to VM. For ST, the equivalent ratios were 3:1 and 1:1, showing that a single dominant gene was responsible for rust resistance. The broad sense heritabilities were >0·91 for uredinial diameter and 0·1–0·33 for the number of uredinia. There were significant overall correlations between data from inoculations with VM and those from inoculations with ST in the number of uredinia, uredinial diameter and disease scores (Spearman’s rank correlation coefficients = 0·31–0·75).     

Occurrence of watermark disease of willows in Japan

The watermark disease of willows was recently identified in Japan for the first time, in the northern island of Hokkaido. During spring and summer, the leaves and branches of affected trees suddenly wilted and some trees died. When affected branches or trunks were cut, a distinct, watery, reddish-brown or brownish-black stained zone (watermark) was seen in the sapwood. The causal bacterium was isolated from the watermark and identified as Erwinia salicis by its bacteriological characteristics. Inoculation tests confirmed its pathogenicity to willows.     

基于叶、枝特性的柳树苗期观赏性评判

[目的]建立基于叶、枝特性的柳树观赏性评判模型,快速评判柳树无性系的观赏性。[方法]以在北京地区适应性良好的20个柳树无性系1年生苗为试验材料,确立与叶、枝特性相关的13个评价指标,利用层次分析法建立快速评判柳属树种观赏性的结构模型。据柳树的观赏特性并结合专家意见,拟定评分准则。构造判断矩阵并进行一致性检验,确定各指标对总目标的权重。柳树无性系性状的分值乘以对应权重得出综合分值,根据综合分值对其进行聚类,根据聚类结果划分等级。[结果]评价模型的准则层中,叶片所占权重为0.75,枝干所占权重为0.25。因子层中各指标对总目标的权重排序为:成叶颜色F2(0.255 9)叶片形状F3(0.152 7)幼叶颜色F1(0.127 3)侧枝颜色F11(0.080 2)小枝颜色F10(0.074 0)叶片密度F4(0.066 7)叶长F6(0.052 6)叶面积F5(0.047 1)主干颜色F12(0.039 2)发枝角度F9(0.031 5)叶宽F7(0.029 9)发枝数量F13(0.025 3)托叶F8(0.017 9)。成熟叶色、叶片形状、幼叶颜色、侧枝颜色和小枝颜色是影响柳树观赏性的主要因子。根据综合得分和聚类结果,将20个柳树无性系划分为4个等级:第Ⅰ等级包括红叶腺柳、SH31、绵毛柳、旱柳、垂109、苏柳J799、金丝垂柳,观赏价值最高;第Ⅱ等级包括银柳、毛枝柳、竹柳、黑柳19,观赏价值较高;第Ⅲ等级包括圆头柳、DQ1、漳河柳、垂爆柳、G7、朝鲜柳、杞柳,观赏价值中等;第Ⅳ等级包括沙柳、蒿柳,观赏价值较低。[结论]利用层次分析法建立的柳树观赏性评价模型可以有效地从叶、枝特性方面快速评判出观赏价值高的柳树无性系,为柳树的进一步选育和园林应用提供参考。