“宁杞4号”的选育

宁杞4号是在宁夏枸杞栽培品种一大麻叶的基础上选育出的枸杞优良品系。具有早产、高产、优质等特点。宁杞4号的产量和品质与宁杞1号相当,但抗锈螨、瘿螨和抗黑果病能力强于宁杞1号。于2005年3月由宁夏林木品种审定委员会审定通过为"林木良种"。     

新疆黑果枸杞瘿螨虫瘿发生与螨量的关系

通过测量虫瘿长径、短径、厚度和质量,统计虫瘿内瘿螨(Aceria pallida keifer)数量,分析黑果枸杞(Lycium rathenicum Murr)瘿螨虫瘿与螨量的关系,以期建立虫瘿大小与瘿内螨量关系的数学模型,为科学防治瘿螨危害提供理论依据。结果表明:虫瘿长径在2.1～3.0 mm区间、短径在1.1～2.0 mm区间、厚度在1.6～2.0 mm区间时瘿螨的数量最多。虫瘿的长径、短径、厚度和质量与瘿内螨量均呈显著正相关关系,其中质量与瘿内螨量高度相关。虫瘿质量与瘿内螨量关系的回归方程y=13.86x+8.23,可作为估算瘿内螨量的模型。     

枸杞瘿螨的发生及防治

枸杞是１种多年生观果类小灌木 ,其果枸杞子可入药 ,并具有较高的营养价值 ,但在栽培中较易发生瘿螨 ,影响产量和观赏价值。我校标本园种植的２０棵枸杞 ,枸杞瘿螨危害普遍 ,被害率１００%,且危害严重 ,萌芽开始危害 ,将展叶就可见到螨瘿 ,严重时几乎叶叶有螨瘿。１枸杞瘿螨的形态特征枸杞瘿螨（ＥｒｉｏｐｈｙｅｓｐａｒａｗａｇｎｏｎｉＫａａｕｇ）也叫痣志、虫包子。属蛛形纲、蜱螨目、瘿螨科。成螨、若螨、卵都在螨瘿内。１ .１成螨体长０.１８ｍｍ ,橙黄色 ,体圆锥形 ,足２对 ,爪钩复羽状 ,口器向前下方斜伸 ,胸部背刚毛２对 ,体侧有…     

甘肃祁连山国家级自然保护区杨属林木病害发生现状及防治对策

2015-2018年,通过林业有害生物普查和监测调查,采集记录到祁连山国家级自然保护区杨属林木林木病原63种,其中,真菌界51种、原生生物界9种、植物界1种、动物界2种。近年来,呈块状或大片分布,造成灾害的杨属林木病害主要为杨树污黑腐皮壳腐烂病、杨树马格纳斯栅锈菌锈病、杨树杨绒毛瘿螨毛毡病3种。提出了杨属林木病害防治对策。     

毒死蜱、乙酰甲胺磷、阿维菌素防治枸杞瘿螨药效试验

枸杞生长期长，害虫种类多且危害严重。枸杞瘿螨是危害枸杞的主要螨类，危害广泛而严重。除4月中旬枸杞展叶，5月下旬，6月上旬新枝萌发瘿螨向嫩叶、新枝扩散而暴露于瘿外，其余时间都在瘿内危害，防治难度非常大。该试验在室内就40%毒死蜱、30%乙酰甲胺磷、0.9%阿维菌素3种药剂毒力及其对枸杞瘿螨防治效果进行试验检测，表明这3种药剂对枸杞瘿螨均有显著的防治效果，可以在生产中推广应用。     

枣树锈瘿螨对枣树几项生理指标的影响

枣树锈瘿螨对枣树几项生理指标的影响季延平仝德全侯玉芹杜华兵（山东省林科所，２５００１４）刘爱兴李榜庆崔广华（乐陵市林业局）枣树锈瘿螨（ＥｐｉｔｒｉｍｅｒｕｓｚｉｚｙｐｈａｇｎｓＫｅｉｆｅｒ．）又称枣树锈壁虱，隶属蜱螨目、瘿螨科。该害螨在山东、河北、河...     

乌桕害虫名录

通过大量的野外调查及文献信息查询,查明了乌桕Triadica sebifera害虫种类及分布,整理出较为全面的乌桕害虫名录,共包括8目53科189种昆虫及1种隶属于真螨目瘿螨科的瘿螨——乌桕皱叶刺瘿螨Phyllocoptruta sapii KuangZhuo。     

梨上瘿螨田间发生与消长规律研究

梨上瘿螨在甘肃省陇西县梨树上发生普遍,主要以成螨为害嫩叶,受害叶片明显皱缩,叶肉细胞组织结构发生病变。调查发现梨上瘿螨主要以成螨在树皮裂缝、芽鳞下越冬,分别占越冬种群总量的41.79%和37.20%;其次,有少量在介壳虫的死介壳下和剪锯口越冬。梨上瘿螨于4月下旬开始为害,为害高峰期分别在6月上旬和9月上旬,10月瘿螨的种群数量逐渐降低,并寻找越冬场所越冬。     

木樨瘤瘿螨生物学特性的观察

木樨瘤瘿螨Acenis osmanthis Kuang为害桂花,一年发生2～3,代以成螨在虫瘿内越冬,翌年3月下旬至4月初,从老叶爬出侵害幼叶。每头雌螨一般产卵5～7粒于瘿内。夏季高温,该螨呈蛰伏状态。秋天有部分瘿螨从瘿内爬出,但未见为害秋梢或别的越冬场所。桂花不同品种间受害程度差异明显,地势背阴、郁闭的桂花园和苗圃受害重。     

精河县枸杞瘿螨和枸杞木虱病的防治技术

<正>1枸杞瘿螨1.1发生规律枸杞瘿螨主要危害枸杞叶片、嫩枝、花蕾及幼果,刺激受害组织形成虫瘿,螨在虫瘿内寄生、繁殖和为害。花蕾、萼片、嫩枝、果实上的虫瘿形态和叶上的相同。虫瘿在嫩枝上危害性更大,对新抽出的嫩枝条、嫩叶危害尤为严重,可导致枝条不能正常生长、叶小,不能开花结果,直到干枯。枸杞瘿螨可在枸杞的整个生长期内持续发生。精河县枸杞受瘿螨为害十分严重,代数不清。枸杞瘿螨以老熟雌成螨在枸杞的当年生枝条及2年生枝条     

Canopy management possibilities for arboreal Leucaena in mixed sorghum and livestock small farm production systems in semi-arid India

A major problem for small farmers in the semi-arid tropics is the chronic shortage of fodder for draft animals. Leucaena leucocephala has improved productivity in many places in India and in various cropping systems, usually as either a pure crop or in a hedgerow alley-cropping configuration. Mixed cropping with arboreal forms is seldom seen. For off-season fodder production, hedgerows have the disadvantage of being open to unmanaged browsing when unfenced (as is usual). Arboreal forms are generally far less vulnerable. In this paper, the components of production of sorghum and arboreal Leucaena are measured under different intensities of canopy lopping. The most productive management system of those examined was pollarding of the Leucaena at the time of under-sowing with sorghum. In a year with less than 50% of average seasonal rainfall, this system gave a yield of 4.6 tonnes/ha/yr fresh wt fodder and 3.8 tonnes/ha/yr dry wt. of fuel harvests, while increasing the standing crop of wood by 1.8 t/ha/yr and retaining a yield of sorghum grain equivalent to 46% of pure sorghum cropping; the LER of this system was 1.35. Cash values of the alternative management systems were estimated, including the discounted Net Present Value of the standing crop of timber. Maximum value was attained with unlopped pure crop Leucaena followed by pollarded Leucaena with sorghum; pure crop sorghum achieved a lower value. These results demonstrate both the high productivity of Leucaena/sorghum based systems, and the stability of production even in poor rainfall conditions. Pollarding transferred the high future value of Leucaena timber to the present value of sorghum grain and fuelwood.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Modeling spatial variability and pattern of rust and brown eye spot in coffee agroecosystem

The advent of Precision Agriculture has made possible the analysis of complex spatial patterns of plant disease epidemiology considering statements of integrated disease management. The objective of this work was to use geostatistics, statistics and geographical information systems to characterize the structure and magnitude of spatial dependency of rust (Hemileia vastatrix) and brown eye spot (Cercospora coffeicola) incidence and severity in coffee agroecosystem cultivated with Catuai Vermelho IAC-99 (Coffea arabica L.). Evaluations of incidence and severity of rust and brown eye spot were accomplished at 67 georeferenced points arranged in 6.6202 ha of coffee crop, in the years of 2005, 2006 and 2007. Exponential models of covariance enabled the characterization of the magnitude and structure of rust and brown eye spot spatial variability in the evaluated dates. Ordinary block kriging presented satisfactory performance to map rust and brown eye spot outbreaks based on kriging error coefficients. Kriged maps enabled the visualization of intensity of rust and brown eye spot in each evaluation date. Assessments of incidence and severity presented highly statistical correlation based on linear regression models, also confirmed by the spatial variability of kriging maps. Kriging maps of rust and brown eye spot enabled to observe that intensity of disease was dispersed in foci patterns along the coffee plantation, indicating that the current strategy of disease control based in total area may be replaced by site specific disease management, with less environmental impact and sustainability of coffee crop, according to statements of integrated disease management and precision agriculture.     

Nutrient cycling and growth in forest ecosystems of south western Australia: Relevance to agricultural landscapes

Nutrient and hydrologic cycles in harvested native forests in southern Australia are largely balanced. For example, we have little or no evidence of any decline in nutrient capital or availability in harvested forests. Short-term and small-scale reductions in evapotranspiration due to loss of leaf area after harvesting are adequately balanced at the landscape scale by large areas of regenerating or older-age forest. In contrast, agricultural systems on similar soils are a) dependent on large inputs of fertilisers to maintain growth and b) frequently subject to increasing salinity and waterlogging or other forms of degradation. The large-scale replacement of long-lived communities of perennial and often deep- rooting native species with annual crops or other communities of shallow-rooting species might be better managed within the framework of knowledge developed from studies of native plant communities. However, application of such a mimic concept to systems of low natural productivity is limited when agricultural systems require continued high productivity. Nonetheless, the mimic concept may help in developing sustainable management of agriculture on marginal lands, and contribute to the nutritional resilience of agroecosystems. Relevant characteristics for mimic agroecosystems in south western Australia include: high species diversity, diversity of rooting attributes, utilisation of different forms of nutrients (especially of N and P) in space and time, and the promotion of practices which increase soil organic matter content. This revised version was published online in June 2006 with corrections to the Cover Date.     

Native woody species regeneration in exotic tree plantations at Munessa-Shashemene Forest,southern Ethiopia

Regeneration of native woody species was studied in the plantations and the adjacent natural forest at Munessa-Shashemene Forest Project Area, Ethiopia. The aim of the study was to test the hypothesis that tree plantations foster regeneration of native woody species. A total of 60 plots, having 10 × 10 m area each, were studied in monoculture plantations of 4 exotic species (Cupressus lusitanica, Eucalyptus globulus, E. saligna, Pinus patula) and an adjacent natural forest. Ages of the plantations ranged between 9 and 28 years. Soil seed bank analysis was also undertaken from soil samples collected in each of the 60 plots to examine the similarity between the soil seed flora and aboveground vegetation. A total of 56 naturally regenerated woody species were recorded beneath all plantation stands with densities ranging between 2300 and 18650 individuals / ha in different stands. There was a significant difference among plantation stands with regard to understorey density (standard deviation: 4836 ± 1341). Vegetation diversity was assessed through analyses of floristic composition, species richness and abundance. Generally, seedling populations were the most abundant components of the regeneration in most of the plantation stands, forming 68 % of the total regeneration count in all stands. A total of 77 plant species represented by 44 herbs, 13 woody species, 8 grasses and 12 unidentified species were recorded in the soil seed bank from all stands. Similarity between the soil seed bank and aboveground flora was very low implying that the role of soil seed banks is negligible rather dispersal plays an important role in the process of regeneration. These results support the concept that forest plantations can foster the regeneration of native woody species, thereby increasing biological diversity, provided that there are seed sources in the vicinity of the plantations.     

Measurement of Green Plank Shape for Prediction and Elimination of Compression Wood

The objective of this study was to predict the amount and the distribution of compression wood (CW) within a Norway spruce [ Picea abies (L.) Karst.] plank based on green plank curvature. The findings indicated a possibility of predicting the longitudinal distribution of CW from the green plank curvature. Areas free from CW showed a typical concave shape in relation to the centre of the log, while CW was present when a convex shape was shown. The larger the magnitude of convex curvature, the higher the concentrations of CW that could be found, and a larger fraction of dried planks was rejected due to excessive warp. This study also determined what information can be used to eliminate areas of high concentrations of CW by cutting and how cutting affects the grading results with respect to warp. Over 50% of the plank length showing a high concentration of CW (>30% of the cross-cut volume) was successfully cut off. Cutting strategies based on predicted CW concentrations resulted in a 10-40% increase in accepted plank length.     

闽南山地木荷林套种南方红豆杉的试验

为了解南方红豆杉在闽南山地生长所需的环境条件,开展了木荷林下套种南方红豆杉的试验研究,结果表明,在较高郁闭度的木荷林中套种南方红豆杉,随木荷林郁闭度的增大,南方红豆杉的树高、地径和生物量降低,叶绿素含量减少,养分含量下降。郁闭度为0.5的木荷林套种南方红豆杉,其生产力最高,叶绿素含量和养分含量均最大。     

杨树天牛灾害可持续控制策略与技术

人工营建的森林生态系统组分过于单一 ,配置不当是三北地区森林生物灾害严重的根本原因。主要控制策略包括御灾控灾阵地前移 ,控制目标从种群密度控制转为灾害控制 ,对灾害调控从“点状调控”上升为“网状调控” ,提高对“潜在”生物灾害的预警能力。提出生物多样性与生态系统稳定性原理、风险分散理论和抗性相对论作为多树种合理配置抗御人工林生物灾害的 3大理论基础。以多树种合理配置控制杨树天牛灾害为实例 ,从结构和功能的关系 ,将现有防护林划分为 3类 :即一代林网、二代林网和加强型二代林网 ,分析了树种配置结构和抗天牛灾害的功能。进一步将加强型二代林网配置树种类群划分为非寄主树种、目标树种 (或抗性树种 )和诱饵树 ,并对各自的功能进行了定位 ,提出了较为合理的抗御天牛灾害的多树种配置模式以及简便有效的诱饵树管理技术。最后 ,以防护林 (特别是农田防护林 )的经营和管理由静态转变为动态为前提 ,探讨了诱饵树管理的一些新思路     

Spatial distribution of fallen shoots of Scots pine pruned by pine shoot beetles (<Emphasis Type="Italic">Tomicus</Emphasis> spp.), and evaluation of methods of shoot collection in central Poland

Methods of spatial distribution of fallen shoots, pruned by pine shoot beetles, and estimation of efficiency of methods based on collection of fallen shoots and used in forecasting of the occurrence of these insects, are presented in this paper. The fallen shoots were distributed in clusters. The distribution was statistically different from random. Relative errors in estimation of shoot-fall density were the smallest in study transects. Early and late autumn and the following spring, after the snow melt, are the optimum seasons for collecting fallen shoots.