两种引诱剂对松褐天牛诱捕效果的比较

为筛选松褐天牛最佳引诱剂,有效监测和降低松褐天牛成虫种群密度。使用ZM-60型松褐天牛专用诱捕器,在宜昌市开展了采用APF-1型和BF-1型引诱剂诱捕松褐天牛成虫的研究。结果表明:APF-1型引诱剂效果略好于BF-1型引诱剂。松褐天牛的羽化高峰期在6月-8月,也是防治松褐天牛的最佳时期。     

豫南松材线虫病重点预防区松褐天牛种群动态研究

利用FJ-MA02型新一代松褐天牛引诱剂及诱捕器诱集松褐天牛成虫,通过连续3a的观察研究,掌握了松褐天牛在驻马店的种群分布规律。同时,针对不同区域提出了防治建议。     

M-99引诱剂有效引诱范围及余杭区松褐天牛成虫发生规律

通过试验确定，M—99引诱剂引诱松褐天牛Monochamus alternatus Hope成虫的有效距离为70m，引诱有效范围为1．5hm^2；用不同色泽的油漆在天牛成虫鞘翅背上做标记是成功可行的；从饲养笼内收集的松褐天牛成虫做好油漆标记，在室内饲养到第2天傍晚进行林间放飞的诱捕回收效果最好，其40、60、70m的总回收率为43．79％，60m处的回收率达70％；余杭区松褐天牛成虫发生始见期在5月初，终见期在9月底，5月下旬至8月中旬为盛期，是防治松褐天牛成虫的最佳时期。     

引诱剂诱杀松墨天牛成虫效果初报

松墨天牛(Monochamus alteratus)是松材线虫病的重要传播媒介昆虫。诱杀松墨天牛成虫，减少松墨天牛虫口密度是防治松材线虫病的有效防治方法之一。笔者于2003年5—7月在重庆万州区天城镇松材线虫病发生区及发生区外围采用引诱剂进行了诱杀松墨天牛试验。现将试验的初步结果报告如下，以供探讨。     

不同引诱剂和诱捕器对松墨天牛的林间引诱效果

2006年和2007年,采用不同的诱捕器和引诱剂,对泸县和富顺的马尾松林中松墨天牛成虫进行了诱捕.结果表明自制SC-1型松墨天牛引诱剂和A-3型松墨天牛引诱剂对松墨天牛成虫的引诱效果基本相同.替代型塑料质诱捕器对松墨天牛成虫的引诱效果只有YB-50型铁质松墨天牛诱捕器的63.70%～81.11%,但塑料质诱捕器成本低、安装简便、不易丢失.在林间虫口数量较大的林区,在同一地点连续进行诱捕,可有效减少林间松墨天牛虫口数量,可用于对松墨天牛的防治.而在林间虫口数量较小的林区,采用诱捕的方法对松墨天牛进行防治,则效果较差甚至没有效果.在四川泸县和富顺诱捕的天牛成虫中,尚未发现松材线虫.     

日本松材线虫病的防治现状

<正> 松材线虫病是由松褐天牛传播所致,病害蔓延迅速,造成的损失严重。日本经多年的研究,目前在防治方面采取的主要防治技术有:1.天牛的化学防治:在天牛羽化的初期和盛期各喷一次杀虫剂,能杀死大部份天牛成虫,减少甚至在局部地区遏止病害再发生,施药方式有地面喷洒和飞机喷洒两种。飞机喷洒采用直升飞机,从林冠上10m高撒     

应用天牛引诱剂监测防治松褐天牛试验初报

利用A-3型和M-99型天牛引诱剂监测诱杀松褐天牛,结果表明:松褐天牛在湖北省恩施市马尾松林区发生期为5月下旬～9月上旬,大量发生期为6月10日～7月31日,同时采用该方法可以杀灭大量的松褐天牛。     

诱木引诱剂防治松褐天牛试验

诱木引诱药剂防治松褐天牛推广试验结果表明,诱木引诱剂33.3%药液是最佳经济浓度。诱木设置于山脊或山腰诱集效果较好;全县是松褐天牛适生区,其中缠溪等7个乡镇应划为重点治理区,沙子坡等6个乡镇为一般治理区,合水等4个乡镇为监测保护区。经过多年治理,现松褐天牛数量已明显下降,诱木防治松褐天牛效果良好。     

几种诱杀松墨天牛方法的效果比较及评价

利用３种方法诱杀松墨天牛成虫的试验结果表明,松饵木能引诱到补充营养的松墨天牛成虫,且雌成虫能在松饵木上产卵,引诱剂对引诱怀卵的松墨天牛成虫的效果较好。引诱剂和松饵木使用方便、安全,成本较低,大面积应用可降低松墨天牛种群密度,减少松材线虫传播机会。但单独使用达不到防治松材线虫病的目标。灯光诱杀远不如引诱剂和松饵木,且其成本高,安全性差,用于松墨天牛防治不宜提倡。利用引诱剂和松饵木在监测松墨天牛及松材     

松褐天牛引诱剂诱捕效果试验

为筛选适合本地松褐天牛监测和防治工作的引诱剂和诱捕器,以提高监测和防治效果,松褐天牛羽化盛期,选用目前国内较常用的两家单位生产的产品进行对比试验。试验结果表明:2种引诱剂对松褐天牛都有一定的引诱效果。APF-I型引诱剂及配套诱捕器诱捕松褐天牛的总数量是FJ-MA-02型引诱剂及配套诱捕器的2.85倍,且操作较后者简便,适宜在生产中推广应用。     

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.     

Growth of Mixed Birch-Coniferous Stands in Relation to Pure Coniferous Stands at Similar Sites in South-eastern Norway

Mean age, mean and top heights and yield were studied in 20 mixed stands of birch ( Betula pubescens Ehrh. and B. pendula Roth) and Picea abies (L.) Karst. and nine mixed stands of birch and Pinus sylvestris L. in south-eastern Norway. Each mixed stand and the adjacent pure coniferous stand (control) were growing under the same site conditions and had not been commercially thinned. There were no significant differences in mean age at breast height or in top heights between birch and conifers in the mixed stands, while mean height was significantly higher for birch than for spruce. A growth index was calculated based on total volume and age at breast height. For the spruce sites the growth in young mixed stands (birch < 17 m) was superior to that of pure spruce, while the difference was insignificant in older stands. The growth index correlated positively with the ratio between generatively and vegetatively regenerated birch trees, and negatively with the age of the oldest species in the mixture and with site quality. For the pine sites there was no significant difference in the growth index between mixed birch-pine and pure pine stands. A mixture effect of birch on the volume yield of spruce or pine could not be demonstrated.     

Defoliation by the Needle-shortening Pine Gall Midge,Thecodiplosis brachyntera,on Pines in Central Sweden

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.     

Boron in forest trees and forest ecosystems

This review critically examines the role of boron (B) in forests in view of recent findings on B nutrition and the continuing occurrence of B deficiency. Many perceptions about the role of B in plants and its uptake and mobility have been altered since the last review on B in forest trees in 1990. Now there is evidence for a fundamental role of B in the formation of the pectic structure in primary cell walls in plants, and further roles in membrane function are being explored. In plants, channel-mediated B uptake, active B uptake and B uptake by mycorrhizas have been shown, B transporters have been identified, and B retranslocation has been shown. We explore these findings and their consequences on forest trees and on ecosystems that they dominate. Particular emphasis is placed on B retranslocation and B in mycorrhizal symbiosis, given their importance in trees.     

Survival and Growth of Picea abies Regeneration after Shelterwood Removal with Single- and Double-grip Harvester Systems

Three stands in Sweden were followed for 7 yrs to study the survival and growth of Norway spruce [Picea abies (L.) Karst.] regeneration after shelterwood removal with single- and double-grip harvester systems. The height of all seedlings within circular plots was recorded before and after final cutting. The tallest seedling and one randomly selected seedling on each circular plot were permanently marked and their annual height growth was measured each year during the period 1993-1999. No significant differences between single- and double-grip harvester systems were found with respect to their effects on regeneration density, survival or annual height growth. The annual height growth of the individual seedlings after shelterwood removal was significantly correlated with seedling height before shelterwood removal. Significant differences were found in annual height growth between seedlings with high and low vitality. Logging damage did not affect the annual height growth. Several practical conclusions were drawn. First, the choice of harvester system does not affect seedling height growth or survival after shelterwood removal. Secondly, the removal of a 200 m³ shelterwood with 200 stems ha^-1 does not seem to constitute a serious problem for seedling survival and growth. Finally, estimated vitality and seedling height both seem to be fairly good predictors of postrelease survival and growth.     

Development of Pinus sylvestris Main Stems Following Three Different Precommercial Thinning Methods in a Mixed Stand

Reducing competition by point cleaning may be an attractive alternative to conventional precommercial thinning in forestry. In this study, survival and development of main stems of Scots pine (Pinus sylvestris L.) following point cleaning were examined in a mixed stand of mainly Scots pine and birch (Betula pendula Roth and Betula pubescens Ehrh.) in northern Sweden. Treatments studied were: no precommercial thinning, conventional precommercial thinning, point cleaning of all secondary stems, and point cleaning of only the secondary stems that were higher than the main stem, within a radius of 0.8 m from the main stem, respectively. A randomised complete block design with three replicates was used. Measurements taken 13 growing seasons after these treatments showed that conventional precommercial thinning was the best treatment for retaining Scots pines as main stems. However, conventional precommercial thinning resulted in the poorest timber quality of the remaining Scots pines in terms of stem taper, thickest branch diameter and relative live crown height. In conclusion, point cleaning has to be followed by a complementary cleaning operation if the objective is to retain Scots pines as main stems in such mixed stands.     

Tree planting for dryland salinity control in Australia

Dryland salinity is emerging as a major form of land and water degradation in southern Australia, particularly in Western Australia, South Australia and Victoria, and to a lesser extent in New South Wales, Tasmania and Queensland.Tree planting, in combination with other vegetation treatments, is regarded as a leading solution to dryland salinity. Research has now shown that planting trees can significantly lower groundwater tables, and thereby reverse the causal process of salinisation. Substantial progress has been made towards answering the basic questions of which species to grow, how to plant, where to plant, at what density and configuration to plant, and how much area to plant. The economic potential for commercial tree planting has given impetus to partial reforestation in higher rainfall (> 600 mm yr^–1) areas. Even so, serious constraints are apparent, relating primarily to cost, uncertainty and attitude. The future should bring increasing community input and control, technical refinement and gradual adoption, provided all aspects of the issue are well researched, relevant information is well communicated and programmes are well administered. Some specific requirements for future research are identified in this review.     

Effect of Cuttings on the Scenic Beauty of a Tree Stand

The opinions of 207 respondents on the visual effects of seven different cutting types were asked using a nine-point verbal scale ranging from ''worsens very much'' to ''improves very much''. Other estimates were obtained by letting the same respondents evaluate photographs of stands which had been treated with different cuttings. The direct questions gave results quite similar to the evaluations of photographs for all but young respondents, indicating that most respondents were able to imagine the effect of the treatment correctly. The results based on the evaluation of photographs indicated that the effect of regenerative cuttings is negative while the impact of thinnings is positive. After a few years of cutting the stand is already regarded as clearly more pleasant than immediately after the cutting. Natural regeneration with seed trees seems to be a way to avoid the very negative immediate impact of clear-felling, especially in the case of Scots pine. Women, young, urban people and those who do not own forest or have work related to forests tended to experience thinnings less positively and saw regenerative cuttings as more harmful than the other test groups did.     

Pinus contorta growth in northern Sweden as affected by soil scarification

The aim of this study was to quantify the effects of different soil scarification methods on tree growth. Soil scarification influenced stem volume and stem biomass yield of lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) in a 17-year-old field trial in boreal Sweden. Soil scarification (disc trenching, mounding and ploughing) resulted in an average stem volume yield of 3.1 and 34.2 m³ ha^–1 on the poor and intermediate sites, respectively, while corresponding values for no soil scarification were 0.9 and 16.7 m³ ha^–1. In comparison to no scarification, ploughing increased volume yields by 500% on the poor site and by 200% on the intermediate sites. The ranking according to stem volume yield was ploughing > disc trenching = mounding no soil scarification. Averaged over the two sites, the mean annual increment of stem biomass was 219% and 145% higher (in d.w., 0.26 kg and 0.34 kg per sample tree) after ploughing compared with no soil scarification, for the average and dominant sample trees, respectively. Although not significant, the increased growth rate after soil scarification decreased the average stem basic wood density of the sample trees with 1.6% and 5.3%, at the poor and intermediate sites, respectively. In conclusion, soil scarification significantly increased the 17-year stem volume yield compared with no scarification. The results also indicate that the difference in stem biomass yield between ploughing and the other methods, especially no soil scarification, will increase even more in the near future.