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1.
刘氏短须螨Brevipalpus lewisi Mc Gregor是上海地区危害水杉Metasequoia glyptostroboides的主要有害生物之一。笔者进行野外释放胡瓜钝绥螨Amblyseius cucumeris防治刘氏短须螨试验,发现胡瓜钝绥螨对刘氏短须螨有一定的防治效果,释放3个月后防效最高,为75.28%。 相似文献
2.
应用实验种群生命表数据分析毛竹林本土优势种竹盲走螨和引进种胡瓜钝绥螨对毛竹4种害螨南京裂爪螨、竹裂爪螨、竹缺爪螨、竹刺瘿螨的控制能力。结果表明①胡瓜钝绥螨取食上述4种害螨的世代存活率分别为90．4％、77．55％、87．93％、81．63％，每雌总产卵量分别为38．12粒、45．77粒、35．59粒、30．26粒，而乡土优势种竹盲走螨取食上述4种害螨的世代存活率分别为95．23％、100％、87．7％、80．48％，每雌总产卵量分别为44．5、46．8、41．15、20．1粒；②竹盲走螨以南京裂爪螨为猎物时其内禀增长率(0．155)与引进种胡瓜钝绥螨(0．154)相近，均明显高于南京裂爪螨(0．1089)；③竹盲走螨以竹裂爪螨为猎物其内禀增长率(0．152)与胡瓜钝绥螨(0．152)相同但明显低于竹裂爪螨(0．192)；④竹盲走螨以竹缺爪螨为猎物时其内禀增长率为(0．148)明显低于引进种胡瓜钝绥螨(0．175)和其猎物(0．185)；⑤竹盲走螨取食竹刺瘿螨易大量逃跑，雌螨产卵量低，引进种胡瓜钝绥螨取食竹刺瘿螨能正常生长发育，但是其内禀增长率(0．144)明显低于其取食上述其余3种害螨的内禀增长率，产卵量高于当地种竹盲走螨，并描述1998年以来每年5—6月助迁人工繁殖的胡瓜钝绥螨控制毛竹害螨蔓延的效果。 相似文献
3.
近日,顺义区林业局首次在顺丽鑫果园和双河果园进行了“以螨治螨”生物防治试验示范,共释放害虫天敌胡瓜钝绥螨9万余只,用来防治大棚里蜜桃和樱桃树上的山楂叶螨。通过试 相似文献
4.
进行了川硬皮肿腿蜂对天牛的防治效果和中华甲虫蒲螨对小线角木蠹蛾的防治效果试验,结果表明:川硬皮肿腿蜂释放量80～100头/株(1管/株)的天牛被寄生率达37.65%～45.08%,平均41.70%;释放量160～200头/株(2管/株)的天牛被寄生率达40.79%～46.03%,平均43.77%;两种释放量的平均防效基本相当,总寄生率43.12%,经济释放量为80～100头/株(1管/株)。中华甲虫蒲螨释放量1～2万头/株(1管/株)的小线角木蠹蛾的防效达41.08%～46.71%;释放量2～4万头/株(2管/株)的小线角木蠹蛾防效达42.38%～48.33%;总防效在43%～46.12%,平均防效44.17%。两种释放量防效基本相当,经济释放量为1～2万头/株(1管/株)。经过2年多的观测研究,证实川硬皮肿腿蜂和中华甲虫蒲螨均可适应沧州市的自然环境和气候环境,对天牛、小线角木蠹蛾等多种蛀干性害虫均有良好的防治效果。 相似文献
5.
研究了中华甲虫蒲螨(Pyemotes zhonghuajia Yu,Zhang and He)对危害油松的松梢螟(Dioryctria pryeri、Di-oryctria rubella)田间防治效果。采用单株透气袋固定在树主干分叉处的方法释放蒲螨,进行不同释放时间、释放量对松梢螟的控制效果试验,通过对释放后的平均防效进行差异显著性分析,确定蒲螨释放的适宜时期和经济释放量。结果表明在北戴河地区5月10-20日释放蒲螨,防效明显好于后期2次释放。在适宜蒲螨释放时期内,每次释放量为20万、40万、80万头蒲螨/株,平均防效差异不显著,因此20万头蒲螨/株释放量可作为经济释放量指标。5月10日释放20万头蒲螨/株,20d后调查,平均防效为91.40%。利用中华甲虫蒲螨对松梢螟进行生物防治效果明显。 相似文献
6.
在试验室内,用番茄瘿螨[Eriophyes lycopersici(Wolffenstein)]饲养钝绥螨(Amblyseius gossipi El-Badry),完成了其生活史。对钝绥螨的未成熟期和成螨做了观察。整个未成熟期平均需取食番茄瘿螨57头,然而雌成虫每日平均需取食91头。只要取食了这些猎物,每日就可产卵2.7粒。 相似文献
7.
针对中华甲虫蒲螨对蛀干害虫双条杉天牛的寄生效果进行了研究。经过在室内试验,结果表明:双条杉天牛的幼虫接种蒲螨后,在2 h内就可以导致幼虫死亡。蒲螨从取食开始直到产生后代,在25℃的恒温箱内需要7 d左右。在室外则采用淹没式的方法释放蒲螨,按照植株胸径数据释放蒲螨(20000头/cm),根据高中低密度3个规格,分别采取45万头/株、30万头/株、15万头/株三种处理方式进行试验。释放后在第10 d、20 d、30 d、40d分别进行了观测统计,结果发现:采用平均防效的方法并没有明显差异,3种处理方式效果基本相当,平均防治数据基本在83.71%~85.98%。经过试验可以看出,采用中华甲虫蒲螨控制双条杉天牛效果显著。 相似文献
8.
采用每667 m2施药100 mL、130 mL、150 mL 8%氯氰菊酯(触破式)微囊剂3种不同处理喷雾防治天然柳林内的星天牛,结果表明:每667 m~2施药100 mL防治效果达80%左右,每667 m~2施药130 m L、150 m L防治效果均接近100%,建议生产上采用每667 m~2施药130 mL。 相似文献
9.
研究了寄生性天敌蒲螨对多毛小蠹和光肩星天牛的控制作用。结果表明:在温度20±2℃、相对湿度50%±5%的室内环境下,蒲螨对多毛小蠹幼虫寄生效果较好,寄生率达100%。蒲螨对光肩星天牛幼虫不选择寄生。室外防治试验的结果表明,每厘米胸径释放蒲螨量20 000头和40 000头的多毛小蠹校正死亡率分别为58.86%和65.01%,寄生效果明显。 相似文献
10.
枣树是优良的经济林树种,是丘陵山区农民脱贫致富的"摇钱树"。但是由于红蜘蛛危害,产量减少,品质下降。介绍了用天敌蒲螨防治红蜘蛛技术,使红蜘蛛死率均达70%以上,提高了防治效果。 相似文献
11.
Summary The heartshakes of some species can contain deposits of inorganic, metal organic, resinous or organic compounds in a pure or concentrated condition. The type of deposit in different genera is discussed. Morphological and chemical examinations have been made of the deposits in the heartshakes of Intsia bijuga, Dacrydium spp., Anisoptera curtisii, Pinus elliotii and Orites excelsa. The deposits were of a benzenoid or terpenoid nature or aluminium succinate.I thank Mr. R. Wearne for organic analyses 相似文献
12.
Although several Armillaria species have been reported in Turkey, there is little information about their ecology in Turkish forests. In this study, we investigated five forest stands, approximately 5–74 ha in size, in Kastamonu province in the Black Sea Region of Turkey for the presence of Armillaria species in stumps and logs. The stands were mixed Abies nordmanniana ssp. bornmülleriana and Pinus sylvestris forests managed using a selective cuttings system; the proportion of fir in the total number of stems and stumps ranged from 36 to 98%. Based on sequence analysis of the internal transcribed spacer and intergenic spacer regions of the rDNA, all rhizomorphs sampled from the stumps and logs were of Armillaria ostoyae. The size of the genets was estimated with random amplified microsatellites analysis of the isolates and ranged from single stumps to approximately 450 m 2. One to seven genets were found in each stand. These results indicate that the genets had arisen from spores and vegetative spread was limited on most sites. 相似文献
13.
Zusammenfassung Seit 11 Jahren arbeitet in Ungarn ein zentralgeleitetes Lichtfallennetz. Die von den 21 Lichtfallen gefangenen Coleopteren-Arten sind vom Jahre 1969 an kontinuierlich bearbeitet. Es hat sich erwiesen, daß gradologische und phänologische Probleme mit Hilfe der Lichtfallen untersucht werden können. Als Beispiele werden die bei Melolontha melolontha L. und Serica brunnea L. gewonnenen Ergebnisse angeführt. Auch die Faunistik wird durch diese Methode bereichert.
Summary A total of 21 light-traps has been used for collecting Coleoptera-species in Hungaria forests since 11 years. Studies have been carried out on Population dynamics and Phenology ofMelolontha melolontha L. andSerica brunnea L. Some rare Coleoptera-species are reported. 相似文献
14.
Dissolved inorganic nitrogen (DIN) (as ammonium nitrate) was applied monthly onto the forest floor of one old-growth forest (>400 years old, at levels of 50, 100 and 150 kg N ha −1 yr −1) and two young forests (both about 70 years old, at levels of 50 and 100 kg N ha −1 yr −1) over 3 years (2004–2006), to investigate how nitrogen (N) input influenced N leaching output, and if there were differences in N retention between the old-growth and the young forests in the subtropical monsoon region of southern China. The ambient throughfall inputs were 23–27 kg N ha −1 yr −1 in the young forests and 29–35 kg N ha −1 yr −1 in the old-growth forest. In the control plots without experimental N addition, a net N retention was observed in the young forests (on average 6–11 kg N ha −1 yr −1), but a net N loss occurred in the old-growth forest (−13 kg N ha −1 yr −1). Experimental N addition immediately increased DIN leaching in all three forests, with 25–66% of added N leached over the 3-year experiment. At the lowest level of N addition (50 kg N ha −1 yr −1), the percentage N loss was higher in the old-growth forest (66% of added N) than in the two young forests (38% and 26%). However, at higher levels of N addition (100 and 150 kg N ha −1 yr −1), the old-growth forest exhibited similar N losses (25–43%) to those in the young forests (28–43%). These results indicate that N retention is largely determined by the forest successional stages and the levels of N addition. Compared to most temperate forests studied in Europe and North America, N leaching loss in these seasonal monsoon subtropical forests occurred mainly in the rainy growing season, with measured N loss in leaching substantially higher under both ambient deposition and experimental N additions. 相似文献
15.
Fineroots (≤ 2 mm diameter) are dynamic components of the forest ecosystems and play important role in water and nutrient acquisition in forests. These roots are sensitive to forest fertilization and therefore, the response of fineroots to nutrient application would provide better understanding of the forest carbon and nutrient dynamics that will be helpful in sustainable forest management plans. Two fertilization treatments, including (1) F400: 400 g P2O5 (16.5%)/tree and (2) F600: 600 g P2O5 /tree, and F0: control (without fertilization), were applied in an Acacia mangium plantation with a planting density of 1100 trees/ha (3 m?×?3 m). The evaluation of fineroot growth across seasons showed that fertilization significantly increased production and subsequent mortality and decomposition. The total decomposition associated with F600 application was 7.95 tons ha?1 year?1, equaling 121% of F400 and 160% of the control. Mortality in F600 was 8.75 tons ha?1 year?1, equaling 111% of F400 and 198% of F0, while production in F600 was 10.40 tons ha?1 year?1, equaling 127% of F400 and 143% of F0. Fineroot production, mortality, and decomposition are seasonally dependent, with higher values measured in the rainy season than in the dry season. Stand basal area increment was significantly correlated with fineroot production (R2?=?0.75), mortality (R2?=?0.44), and decomposition (R2?=?0.48). This study showed that fertilization could facilitate fineroot production, which can then lead to a higher turnover of carbon and nutrients through the decomposition of the greater mass of the fineroots. 相似文献
16.
Foliar nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) concentrations of 5 Symphyomyrtus ( E. botryoides, E. cladocalyx, E. microcorys, E. nitens, E. saligna) and 7 Monocalyptus ( E. agglomerata, E. baxteri, E. globoidea, E. muelleriana, E. obliqua, E. pilularis, E. regnans) species were determined for each of four hill country microsites; upper shady, lower shady, upper sunny and lower sunny
slopes. ANOVA and correlation analysis were used to identify species and microsite effects, and nutrient associations. Significant
( P ≤ 0.0014) species differences were identified for all nutrients, E. botryoides and E. saligna generally had high nutrient concentrations while stringybark species were low, particularly for N and K. Subgeneric contrasts
revealed that Symphyomyrtus species had significantly higher concentrations of P ( P = 0.05) N, K and Ca ( P < 0.0001) but lower Mg ( P < 0.0001) than Monocalyptus. Microsite had less influence on nutrient concentrations than species. N was strongly positively correlated with P and K
in most Symphyomyrtus species but was not correlated with P in Monocalyptus. Mg was positively correlated with Ca but negatively correlated with K in most species. The results indicate that Monocalyptus and Symphyomyrtus species differ in ability to accumulate key macronutrients. 相似文献
17.
Tests in vitro and in situ showed that both mycelial and conidial suspensions of Acremonium mucronatum were antagonistic for Diplodia mutila, a common pathogen on the apical twigs of declining Quercus cerris, Quercus frainetto, Quercus pubescens and Quercus robur. Antagonism was greater with the mycelium than with the conidial suspensions, and was strongest at a test temperature of 20°C. The results suggest that pathogenicity of D. mutila on declining trees may be significantly reduced by the presence of A. mucronatum. 相似文献
18.
This study investigated root biomass and productivity in dominant populations in western Sichuan, China. A total of 4 plots
( Picea balfouriana plantation for 22 age in Maerkang, 9 trees, mean DBH of population for 10.4 cm and height for 10.5 m; Larix maxteriana plantation for 22 age in Wolong, 9 trees, mean DBH of population for 17.0 cm and height for 13.8 m; Abies fabri plantation for 35 age in Ebian, 18 trees, mean DBH of population for 14.1 cm and height for 11.9 m; Larix kaempferi plantation for 23 age in Miyaluo, 8 trees, mean DBH of population for 17.4 cm and height for 14.5 m; a 20 m×25 m plot located
on each of the 4 types in western Sichuan, China) were randomly selected and excavated to a depth of 60 cm for each of the
4 plantation types. To estimate the root biomass of an individual tree using D
2
H, an exponential model was selected with the highest coefficient ranging from 0.94 to 0.99. The total root biomass per hm 2 varied among plantation population types following the order: L. kaempferi (37.832 t/hm 2) > A. fabri (24.907 t/hm 2) > L. maxteriana (18.320 t/hm 2) > P. balfouriana (15.982 t/hm 2). The biomass fractions of a given root size class compared to the total root biomass differed among plantation population
types. For all 4 studied plantation types, the majority of the roots were distributed in the top 40 cm of soil, e.g., 97.88%
for P. balfouriana population, 96.78% for L. maxteriana, 95.65% for A. fabri, and 99.72 for L. kaempferi population. The root biomass fractions distributed in the top 20 cm of soil were 77.13% for P. balfouriana, 77.13% for L. maxteriana, 65.02% for A. fabri and 80.66% for L. kaempferi, respectively. The root allocation in the 0–20, 20–40, and 40–60 cm soil layers gave ratios of 34:12:1 for P. balfouriana, 24:6:1 for L. maxteriana, 15:7:1 for A. fabri, and 64:4:1 for L. kaempferi populations. The root biomass density of dominant plantation population was 10.782 t/(hm 2·m) for P. balfouriana, 8.230 t/hm 2·m) for L. maxteriana, 24.546 t/(hm 2·m) for A. fabri, and 13.211 t/(hm 2·m) for L. kaempferi population, respectively. The root biomass productivity was found to be 0.57 t/(hm 2·year) for P. balfouriana, 0.83 t/(hm 2·year) for L. maxteriana, 0.71 t/(hm 2·year) for A. fabri and 1.64 t/(hm 2·year) for L. kaempferi population, respectively.
__________
Translated from Acta Ecologica Sinica, 2006, 26(2): 542–551 [译自: 生态学报, 2006, 26(2): 542–551] 相似文献
19.
This study quantified tree and soil C stocks and their response to different tree species and clay contents in improved fallows
in eastern Zambia. From 2002 to 2003, soil, and destructively harvested two-year old tree, samples were analysed for C. There
were significant differences ( P < 0.05) in aboveground tree C stocks, and in net organic C (NOC) intake rates across coppicing tree species at Msekera and
Kalunga. Aboveground C stocks ranged from 2.9 to 9.8 t ha -1, equivalent to NOC intakes of 0.8–4.9 t ha -1 year -1. SOC stocks in non-coppiced fallows at Kalichero and Msekera significantly differed ( P < 0.05) across treatments. SOC stocks to 200 cm depth ranged from 64.7 t C ha -1 under non-coppicing fallows at Kalunga to 184.0 t ha -1 in 10-year-old coppicing fallows at Msekera. Therefore, tree and soil C stocks in improved fallows can be increased by planting
selected tree species on soils with high clay content. 相似文献
20.
Abstract. Variation of wood specific gravity from the base to the top of tree and from pith to bark was investigated for Gmelina arborea Roxb. plantations in western Venezuela. Increment cores were taken from thirty trees at five different sections up the stem: 0.1?m; 1.3?m, half total height, 3/4 total height and at the top. These trees were chosen from commercial plantations located at three different sites. Specific gravity was obtained using an X-ray densitometer. The results show that there is an increase in specific gravity from pith to bark. It was also evident that specific gravity decreased from stump to half of the total height, then increased towards the top of the stem. No correlation between specific gravity and height of the tree was found. Correlations in specific gravity with height categories were generally small, and non-significant at level α=0.05.
Palabras clave:
Gmelina arborea, Propiedades de la madera, Gravedad específica
Resumen. En la Gmelina arborea Roxb se estudió la variación de la gravedad específica desde la base hasta el tope del árbol y desde la médula hasta la corteza. Se tomaron muestras de madera provenientes de treinta árboles a cinco alturas diferentes a lo largo del fuste a 0.1?m; 1.3?m, mitad de la altura total, 3/4 de la altura total, y del tope, las cuales fueron seleccionadas de plantaciones comerciales localizadas en tres sitios distintos al occidente de Venezuela. La gravedad específica fue determinada con la ayuda de un densitómetro de rayos-x. Los resultados muestran un incremento de la gravedad especifica desde la médula hacia la corteza. También se encontró que la gravedad específica disminuye de la base a la mitad del fuste y luego aumenta hacia el tope del fuste. No se encontró correlación entre la gravedad específica y la altura del árbol. La correlación entre la gravedad específica y las categorías de altura donde las muestras fueron tomadas son generalmente pequeñas y poco significativas a un nivel de probabilidad α=0.05. 相似文献
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