世界胭脂虫的研究和利用概况

对胭脂虫的分类学、生物学特性、生态学、培育及加工利用等方面近30 a的研究成果进行了概述.胭脂虫共有9种,其中具重要经济价值的为Dactylopius coccus Costa;发育起点温度为16.7 ℃,近30 ℃时发育最快,其发育、存活及繁殖的理想温度为26 30 ℃,在胭脂虫培育地区,降水是影响胭脂虫自然种群数量的主要因素;用胭脂虫干体加工生产的胭脂红色素广泛地应用于食品、化妆品、制药业.胭脂虫的寄主仙人掌也具有很高的利用价值,可果用、菜用、药用及作为牲畜饲料.秘鲁为胭脂虫的主产国,现采用大棚培育胭脂虫的方法.本文同时展望了胭脂虫生产的发展前景.     

胭脂虫实验种群研究

利用人工气候箱,按照正交设计方法,设置了8种不同温度、湿度、光照条件组合,运用生命表技术,对胭脂虫进行了种群动态研究。研究结果表明：15℃以下,胭脂虫卵有少量孵化,但不能完成世代;2D、25、30℃条件下胭脂虫能完成世代。从培育的胭脂虫的怀卵量、种群趋势指数及大小方面比较,以温度25℃、相对湿度60％和80％、光照强度980lx和601x的组合条件为好;胭脂虫的雌雄性比远大于1：1,环境因子对性比具有较大的影响;胭脂虫的种群趋势指数一般大于20,平均约40,对培育十分有利;发育起点温度为9．0℃,世代有效积温为822．9日度;多因素方差分析结果显示,温度为影响胭脂虫发育的最显著因素,而湿度和光照的影响相对较小。     

蔗糖对胭脂虫的助食作用研究

利用蔗糖辅助培育胭脂虫,设置10个不同水平蔗糖浓度,每个水平10组重复,研究不同浓度蔗糖对胭脂虫的助食作用.结果表明:蔗糖对胭脂虫有明显助食作用,适当浓度的蔗糖有助于提高胭脂虫的产量.蔗糖浓度47.5 g·L-1至475.0 g·L-1可提高上虫量;在285.0 g·L-1浓度下,胭脂虫的存活率较高,种群数量变动较小;47.5 g·L-1至380.0 g·L-1均有利于提高雌成虫数量,并明显提高胭脂虫单片茎片的鲜质量和干质量;不同浓度的蔗糖均可提高胭脂虫雌成虫的体积及怀卵量,285.0g·L-1浓度的蔗糖辅助培育胭脂虫效果最明显.     

隐唇瓢虫生物学特性与温度的关系

研究 温度对隐唇瓢虫Cryptolaemus montrouzieri Mulsant发育的影响用回归方程确定了各虫态和全世代的发育历期。夏季各虫态的历期较短,冬季较长,然而发育速度最快的适宜温度为30℃在20℃恒温下饲养的成虫寿命,比在30℃和自热变温的成虫寿命长。在20℃恒温下用葡萄粉蚧Maconellicoccus hirsutus(Green)饲养的瓢虫其寿命比用蜂蜜饲养     

DDSA酯化法制备胭脂虫红色素衍生物

以十二烯基丁二酸酐(DDSA)作酯化剂,对胭脂虫红色素的主要成分胭脂红酸分子进行改性修饰,制得了油溶性较好的胭脂虫红色素衍生物。通过单因素及响应曲面优化试验确定了反应的最佳条件:0.5 g原料,DDSA与胭脂虫红色素的质量比值为2.3,催化剂三乙胺(Et3N)的用量为1.8 mL,温度为67℃,反应时间为6 h,溶剂N,N-二甲基甲酰胺20 mL,此条件下,产物得率为41.59%。通过FT-IR及UV-Vis对目标产物的结构进行表征,表明DDSA与胭脂虫红色素发生了酯化反应,制得的胭脂虫红色素衍生物的λmax及颜色在碱性溶液中受pH值影响较大;其可溶于食用玉米油,有较好的染色效果且稳定性良好,溶解度(20℃)为6.53,有效改良了胭脂虫红色素的油溶性。     

胭脂虫与寄主仙人掌的关系

对采自10个地方的仙人掌进行胭脂虫放虫试验,并对仙人掌进行解剖及营养成分分析,结合胭脂虫的生长情况对胭脂虫与仙人掌种类、内部构造及营养成分的关系进行研究,结果表明,胭脂虫在梨果仙人掌、朱耳掌及缩刺仙人掌上均能寄生,但以梨果仙人掌最好;从秘鲁引进的梨果仙人掌及云南禄丰的梨果仙人掌上胭脂虫生长较好;少刺型的梨果仙人掌上胭脂虫生长比多刺型梨果仙人掌好;仙人掌的表皮越厚,胭脂虫的生长越差,而胭脂虫的寄生能刺激仙人掌维管束的发育;仙人掌中蛋白质、水分含量对胭脂虫的生长具有显著影响。     

基于生命表技术的胭脂虫适生性研究

运用生命表技术,结合采样测定,对胭脂虫在干热河谷区、南亚热带区及中亚热带区的代表点上的生长情况进行了研究。结果表明：南亚热带地区胭脂虫雌成虫虫体较大,怀卵量较多,质量较大,种群趋势指数最大,为最适生区域;中亚热带区域胭脂虫最大,怀卵量最多,质量最大,但种群趋势指数小,世代历期长,年世代数少,为次适生区域;干热河谷区培育的胭脂虫雌成虫虫体小,怀卵量少,质量小,种群趋势指数较小,为适生区域;在各气候条件下,影响胭脂虫种群数量变动的主导因素为卵的孵化率及1龄若虫或2龄若虫期的强降雨。各试验点均未发现大量胭脂虫天敌。     

印榕仙人掌栽培和胭脂虫养殖技术

用胭脂虫干体加工提取的胭脂红,广泛应用于食品、医药、纺织和化妆等行业。胭脂虫（Dactylopius coccus costa）的唯一寄主是仙人掌。中国林科院资源昆虫研究所从墨西哥等地引种印榕仙人掌（Opuntia ficus-indica（L））在元江等地取得成功。文章介绍了印榕仙人掌的栽培和胭脂虫的养殖技术。     

温度对松褐天牛肿腿蜂繁殖和发育的影响

[目的]为了明确温度对松褐天牛肿腿蜂繁殖和发育的影响,进而为其人工繁育和生物防治应用提供科学依据。[方法]在21,24,27,30,33℃的恒温条件下人工繁育松褐天牛肿腿蜂,记录各虫态发育历期及子代数量,并计算各虫态发育起点温度和有效积温。[结果]表明,松褐天牛肿腿蜂各虫态发育历期随着温度的升高而缩短,如5组温度处理下的卵期分别为3.29±0.14,2.89±0.17,2.61±0.14,2.16±0.11和1.86±0.93 d。卵、幼虫、蛹的发育起点温度分别为6.99±2.12,10.67±3.43和13.5±2.71℃,有效积温分别为49.28±5.08,166.67±34.02和225±43.30日·度。温度对子代数量及雄性占比也有显著影响,温度超过30℃后,子代数量及雄性占比显著下降。[结论]适度升温可有效促进肿腿蜂的繁殖和发育,但温度超过适温则不利于母蜂寄生和子代发育,人工繁育松褐天牛肿腿蜂的适宜温度范围是24～30℃。     

温度和赤霉素对胭脂花种子萌发的影响

该文研究了温度和赤霉素处理对胭脂花种子萌发的影响。结果表明:胭脂花种子在15~25℃均有较高发芽率,且在20℃有最高的发芽率、发芽势和发芽指数;30℃的种子发芽率显著低于其它各组。赤霉素能促进胭脂花种子萌发,但各浓度处理间差异不显著;赤霉素浓度为250mg/L时的种子发芽率、发芽势最高,而处理浓度为350mg/L时的种子发芽指数最高。综合认为:在胭脂花播种繁殖时,可采用25℃培养条件下250~350mg/L的赤霉素处理或单用20℃温度对种子进行预处理,促进种子萌发。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.     

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.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.