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在浙江省的马尾松、黑松、湿地松、火炬松、黄山松上采集到为害嫩梢和球果的蛾类昆虫12种,危害严重的有微红梢斑螟、松实小卷蛾和油松球果小卷蛾,火炬松严重受害、湿地松则轻微,不同梢果实虫对松树种类、松梢和球果有选择性,几种害虫蛀食同一球果的混合发生是这类害虫明显的发生特点;编制了幼虫、蛹和成虫的识别检索表,列出寄生天敌昆虫名录,提出了防治方法。 相似文献
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据美国林务局1974年统计,美国共建立种子园4,047公顷,其中81%分布在南部。主要树种为火炬松、美国长叶松、美国红皮松和湿地松。害虫是南方松种子园种子和球果的主要破坏者。蓟马Gnophothrips fuscus对湿地松雌小球果破坏很厉害,甚至在花出现前就进入花芽,并在整个受粉期继续危害,使许多雌小球果致死。南塔克特松梢小卷蛾(Rhyacionia- 相似文献
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国外松的种实害虫及其防治技术 总被引:1,自引:0,他引:1
调查表明,为害广东省国外松种子园的种实害虫有11种,其中以油松球果小卷蛾、微红梢斑螟和松实小卷蛾为害最严重。这些害虫的天敌资源丰富,共28种,但尚未有优势种群。化学防治可用2.5%溴氰菊酯10000倍液喷杀,防治效果达82%以上。 相似文献
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黄山松球果害虫主要有松实小卷蛾和松果梢斑螟的幼虫,它们是一类生活隐蔽、危害严重、防治难度大的钻蛀性害虫,通过几年室内外的反复试验研究,提出了防治黄山松主要球果害虫的农药品种、用量(浓度)及施药的最佳时间和方法等。 相似文献
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对松实小卷蛾、松梢螟的为害性和空间格局及在序贯抽样技术中的应用的研究结果表明,二虫对松树为害具有选择性,松实小卷蛾幼虫主要为害侧枝,为害程度火炬松>黑松>湿地松>马尾松,松梢螟为害则以主梢为主,为害程度 黑松>湿地松>马尾松>火炬松.松实小卷蛾和松梢螟的空间格局分别为负二项分布和奈曼分布,松实小卷蛾明显超过防治指标,急待全面防治,松梢螟低于防治指标,可不防治. 相似文献
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以黑松、马尾松和火炬松为研究对象,对其接种松材线虫后4,12,24,48,72,96和120 h的NO和核酸酶的活性进行测定.3种松树接种松材线虫后,针叶内NO平均含量的积累为火炬松<马尾松<黑松,这种差异在12 ~48 h尤为明显;48h后较其割伤处理(CK1)的增加幅度为火炬松>马尾松>黑松.同时3种松树接种后的核酸酶变化趋势存在差异,单链核酸酶活性在4~48 h为火炬松>马尾松>黑松,而火炬松双链核酸酶活性在4~96h时却一直低于马尾松和黑松,这表明不同松树体内单链或双链核酸酶的活性变化与其抗病性有关.且3种松树在接种松材线虫后,表现出症状的时间顺序为黑松最早,马尾松次之,火炬松最晚.这表明NO和核酸酶的变化与松树感染松材线虫后的病程发展密切相关. 相似文献
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经济林害虫发生现状与趋势 总被引:5,自引:0,他引:5
选择安徽省28种主栽及名特经济树种为主要对象,经过1988年至1995年8年的调查研究,探明当前各经济树种害虫种类、发生现状与趋势。在28种经济树种上查出害虫1074种,其中危害程度轻微、中等、严重的害虫分别为868种、137种和69种,分别占害虫总数的80.8%、12.8%和6.4%。经济林害虫垂直结构为食叶害虫(626种)>枝梢害虫(290种)>蛀干害虫(78种)>果实害虫(43种)>根部害虫(37种)。害虫总体发生率78.0%,其中危害轻微、中等和严重的发生率分别为41.3%、22.3%和14.4%。分析提出现阶段害虫发生类型。 相似文献
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采用CEPA、GA3、PP333、B9等植物生长物质,以不同浓度处理马尾松、黑松、湿地松、火炬松枝梢,比较药剂种类和处理浓度对枝梢生长的影响。结果表明: GA3(2 500 mg·L-1)对各供试树种均有显著促进作用(试验3中对湿地松除外);试验1中,5 000 mg·L-1 PP333显著抑制马尾松枝和黑松枝的伸长生长,具有最佳调节效果;试验2中,5 000 mg·L-1 PP333显著抑制湿地松和马尾松枝的伸长生长,具有最佳调节效果;试验3中,5 000 mg·L-1 PP333+5 000 mg·L-1B9复合制剂显著抑制湿地松和火炬松枝梢的伸长生长,具有最佳调节效果。用"Y"型嗅觉仪测定微红梢斑螟成虫对松梢的嗅觉反应,结果表明处理组枝梢对微红梢斑螟成虫驱避效果明显;微红梢斑螟等松梢害虫危害率调查表明,处理枝梢的被害率也明显低于对照枝梢。 相似文献
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利用松属5个树种的EST序列,分别树种查找SSR位点,采用Primer3.0软件进行引物设计。设计的5个树种的EST-SSR引物中:所占比例最高的均为三核苷酸重复,其次是六核苷酸重复,两者之和都达到了64%以上;四核苷酸重复所占比例均为最低。从设计的引物中分别不同树种各选取20对进行引物合成和通用性检测以及马尾松群体检测,结果表明:松属5个树种的EST序列开发的马尾松SSR引物,其在马尾松中的扩增成功率为60%-80%;最高的是辐射松,最低的是海岸松,平均为72%。通用性最好的为辐射松,属内的通用性为94%;属间和科间通用性也分别达到75%和44%。不同树种序列来源的EST-SSR引物,其扩增成功率在10%-30%;最高的是北美短叶松,其次是辐射松,最低的是扭叶松和火炬松;平均为17%。 相似文献
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It has been hypothesized that increasing atmospheric CO(2) concentration enhances accumulation of carbon in fine roots, thereby altering soil carbon dynamics and nutrient cycling. To evaluate possible changes to belowground pools of carbon and nitrogen in response to elevated CO(2), an early and a late successional species of pine (Pinus taeda L. and Pinus ponderosa Dougl. ex Laws, respectively) were grown from seed for 160 days in a 35 or 70 Pa CO(2) partial pressure at low or high temperature (30-year weekly mean and 30-year weekly mean + 5 degrees C) and a soil solution nitrogen concentration of 1 or 5 mM NH(4)NO(3) at the Duke University Phytotron. Seedlings were harvested at monthly intervals and growth parameters of the primary root, secondary root and tap root fractions evaluated. Total root biomass of P. ponderosa showed a positive CO(2) response (105% increase) (P = 0.0001) as a result of significant increases in all root fractions in the elevated CO(2) treatment, but all other main effects and interactions were insignificant. In P. taeda, there were significant interactions between CO(2) and temperature (P = 0.04) and CO(2) and nitrogen (P = 0.04) for total root biomass. An allometric analysis indicated that modulation of the secondary root fraction was the main response of the trees to altered environmental conditions. In P. ponderosa, there was an increase in the secondary root fraction relative to the primary and tap root fractions under conditions of low temperature. In P. taeda, there was a shift in carbon accumulation to the secondary roots relative to the primary roots under low temperature and low nitrogen. Neither species exhibited shifts in carbon accumulation in response to elevated CO(2). We conclude that both species have the potential to increase belowground biomass substantially in response to rising atmospheric CO(2) concentration, and this response is sensitive to temperature and nitrogen in P. taeda. Both species displayed small shifts in belowground carbon accumulation in response to altered temperature and nitrogen that may have substantial ecosystem consequences over time. 相似文献
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The spherical mean of the shoot silhouette-to-total leaf area ratio (STAR) and the shoot transmission coefficient (c) are two key structural parameters in radiative transfer models for calculating canopy photosynthesis and leaf area index. The standard optical method for estimating these parameters might introduce errors in the estimates for species with flexible shoots and needles by changing shoot inclination relative to its inclination in situ. We devised and tested two methods to address this problem. First, we modified the standard optical method by designing an apparatus that allows shoots to be photographed in their original orientation. Second, we developed a faster, model-based approach to replace photography and tested the results against the established approach. We used shoots of three pine species, Pinus echinata Mill. (needle length ~50 mm), P. taeda L. (~150 mm) and P. palustris Mill. (~300 mm). Values of the parameters simulated by the model were similar to those measured from the photographs. In our data, STAR varied about twofold among the pine species and was ~40% higher in shade shoots than in sun shoots of P. taeda. The transmission coefficient for P. taeda shade shoots was also ~40% higher than that of sun shoots of all three species. We tested the versatility of the model by employing it on shoots of two other pine species (P. strobus L. and P. thumbergiana Parl.) as well as on shoots of Tsuga canadensis L. Carr. and Picea pungens Engelm. Regardless of shoot characteristics, the model generated values of shoot structural parameters similar to those estimated with the optical method. Although species-specific and vertical gradients in parameter values are best for modeling radiative transfer in conifer canopies, our results suggest that, in the absence of adequate data, STAR can be approximated as 0.16 for a wide range of shoot structures. For applications requiring angle-dependent parameterization, our new model facilitates rapid generation of these radiative transfer parameters. 相似文献
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对7个松树树种的材积和产脂力进行测定分析,结果表明:地点、重复对材积和产脂力的影响均不大,树种间材积和产脂力差异规律不明显。4个年度数据中,9年生和15年生材积差异达显著和极显著水平,9年生和16年生时产脂力均达显著差异。从树种平均值分析来看,热带松、本种加勒比松和马尾松生长相对较快,而湿地松、巴哈马加勒比松以及火炬松则生长较慢;产脂力较高的是热带松、巴哈马加勒比松、马尾松优树混合种,属中等产脂力的是本种加勒比松和湿地松,产脂力较低的是垌头群马尾松(对照)和火炬松。 相似文献