梨园梨小食心虫性信息素迷向防治技术

为明确梨小食心虫性信息素迷向散发器对单植梨园和毗邻苹果园的梨园内梨小食心虫的防治效果和合理使用密度,本研究于2012、2013和2014年在山西省运城市采用每根含270 mg梨小食心虫性信息素的散发器进行了梨小食心虫迷向防治试验。结果表明,单植梨园和毗邻苹果园的梨园以600、900和1200根/hm²处理,对梨小食心虫的迷向率逐年提高,且高密度处理迷向效果更好;连续使用3年后,梨小食心虫的蛀果率显著低于对照园,单植梨园内防治效果分别为80.00%、90.00%和90.00%,毗邻苹果园的梨园则分别为69.23%、84.62%和84.62%,单植梨园效果好于毗邻苹果园的梨园。综合防治成本和效果,建议单植梨园可使用900根/hm²密度处理,毗邻苹果园的梨园使用1200根/hm²以上密度处理,并建议大面积连片使用3年以上。     

Diurnal and seasonal variations of soil respiration rate under different row-spacing in a Panicum virgatum L. field on semi-arid Loess Plateau of China

Soil respiration(SR) in crop field is affected by environmental factors, agronomic practices and crop types. To clarify how planting density affects the SR dynamics in switchgrass(Panicum virgatum L.) field on the semi-arid Loess Plateau, this research investigated diurnal and seasonal changes of soil respiration rate(RS) under three different row-spacing treatments(20, 40 and 60 cm) in the fourth growing year of switchgrass. Results showed that RS presented a pronounced seasonality under all row-spacing treatments. The highest daily average RS values appeared in August, while the lowest(P0.05) were in September for each row-spacing. Diurnal variations of RS exhibited single-peak curves in each month. Daily average RS increased significantly as row-spacing enlarged during May and August but there was no significant difference among row-spacing treatments in September. Soil water storage in the depth of 0–100 cm had no significant difference(P0.05) among the row-spacing treatments, and similar results were found for soil temperature in 0–15 cm soil depth. Soil respiration temperature sensitivity(Q_(10)) values were 1.0–3.7 during the growing months, which were strongly correlated with air temperature in May and June and the soil temperature at 15 cm depth in August. Higher aboveground biomass production and lower RS in most growth months indicated that 20 cm row-spacing treatment was beneficial for increasing the carbon fixation in switchgrass field. Results also implied that it is necessary to take into account the influence of phenology and root growth of switchgrass on soil respiration for accurately evaluating the carbon cycle in the region.     

不同处理条件对苜蓿叶蛋白凝聚效果的研究

以现蕾期新鲜苜蓿Medicago sativa为材料,采用温度、pH值单因素处理及温度、加热时间、pH值和NaCl质量分数多因素处理,探讨不同方法对苜蓿叶蛋白凝聚效果的影响。结果表明,在单因素条件下,温度以75℃为宜,pH值4.0对苜蓿叶蛋白产量、叶蛋白纯度和粗蛋白提取率有显著影响。而在多因素条件下,叶蛋白的最适凝聚组合条件为温度85℃,时间2min,pH值4.0,以及NaCl质量分数0.4%。     

落叶松八齿小蠹聚集信息素的时空诱集效果

应用落叶松八齿小蠹聚集信息素对内蒙古阿尔山林区落叶松八齿小蠹的年扬飞规律、日扬飞规律、林缘外不同距离以及林内不同高度诱捕器诱集效果等进行了试验。结果表明:落叶松八齿小蠹的成虫发生期从5月中旬开始,到8月底结束,期间有两次明显的扬飞高峰期;成虫活动主要集中在12:00—16:00;聚集信息素对落叶松八齿小蠹的有效引诱距离为200 m左右,在90 m以内引诱效果最佳;林内树干1.5 m处为最佳的诱捕器设置高度。     

亚洲玉米螟性信息素的简易合成法

从价廉的1,12-十二碳二醇出发,经单边酯化和Wittig反应,以45%的总收率合成了亚洲玉米螟性信息素的(Z/E)-12-十四碳烯醇乙酸酯,顺反比为90/10。将所得化合物经构型转化,得顺反比为25/75的(Z/E)-12-十四碳烯醇乙酸酯,产物结构经核磁共振光谱和质谱数据确证。     

Catching Ips duplicatus (Sahlberg) (Coleoptera: Scolytidae) with pheromone‐baited traps: optimal trap type,colour, height and distance to infestation

BACKGROUND: Field trapping experiments were carried out to evaluate effective trap characteristics for maximising Ips duplicatus (Sahlberg) catches in pheromone‐baited traps in China. RESULTS: Window‐slot and cross‐barrier traps had significantly higher catches than multiple‐funnel traps. The colour of window‐slot traps showed a significant effect on catches, with dark colours (black and red) being more effective than light colours, especially white and yellow. Window‐slot traps at a 1.5–2.0 m level caught more beetles than those at either ground level (0–0.5 m) or at 3.5–4.0 m. Ips duplicatus can be attracted to pheromone‐baited traps over a distance of > 100 m from the forest edge in an open grassy field. There was a strong diurnal pattern of flight activity, with catches on window‐slot traps occurring during the daytime with one broad peak at mid‐ to late afternoon. The seasonal flight activity of I. duplicatus as monitored by pheromone‐baited window‐slot traps during 2007–2008 indicated that three major flight peaks occurred in early June, late June–early July and late July respectively, suggesting the existence of a potential second generation. CONCLUSION: The optimal trap characteristics will improve the performance of pheromone‐baited traps as a critical monitoring or mass‐trapping tool to combat outbreaks of this pest species. Copyright © 2009 Society of Chemical Industry     

Mating disruption of California red scale,Aonidiella aurantii Maskell (Homoptera: Diaspididae), using biodegradable mesoporous pheromone dispensers

BACKGROUND: The control of California red scale, Aonidiella aurantii (Maskell), has encountered many difficulties, which has raised interest in alternative control methods. Up to now, the A. aurantii sex pheromone has been used only for monitoring. In a previous work the authors described a biodegradable mesoporous pheromone dispenser for mating disruption. To verify the efficacy of these dispensers, three field trials were conducted, and the results are shown in this paper. RESULTS: The study of the release profile of these dispensers revealed a mean pheromone emission value of 269 µg day^?1 and levels of residual pheromone of 10% at the end of 250 days. During the second flight, an A. aurantii male catch reduction of 98% was achieved in the mating disruption plot of trial 1, 93.5% in trial 2 and 76.7% in trial 3. During the third flight, reductions were 94.1, 82.9 and 68.1% in trials 1, 2 and 3 respectively. Considering damaged fruit with more than five scales, reductions of about 80 and 60% were obtained in the mating disruption plots of trials 2 and 3, respectively, compared with an untreated plot, and a reduction of about 70% in trial 1 compared with an oil‐treated plot. CONCLUSION: Mating disruption has been found to be an efficient technique to control this pest, working equally well to a correctly sprayed oil treatment. Further studies are needed to improve the determination of the time of dispenser application and evaluate the effects of the pheromone on natural enemies. Copyright © 2010 Society of Chemical Industry     

沙地云杉重齿小蠹聚集信息素的试验分析

利用林间生测技术,对内蒙古白音敖包国家级自然保护区的沙地云杉[Picea mongolia (H.Q.Wu) W.D.Xu]重齿小蠹聚集信息素开展了试验分析.结果表明,在不同聚集信息素组分配比的反应试验中,Id+EM+At(20 mg+20 mg+2 mg)的信息素组分配比诱捕效果最好;在不同聚集信息素剂量的反应试验中,最高剂量的Id+EM(200 mg+200 mg)诱捕效果最好;在不同类型的聚集信息素诱芯的反应试验中,开口塑料瓶式诱芯诱捕效果最好.但是,建议在种群监测和大量诱杀中使用海绵塑料袋式诱芯,信息素Id+EM+At的剂量和配比分别为20 mg+20 mg+2 mg和1∶1∶0.1.     

冻融过程中土壤颗粒组成的重建：研究综述

Studies conducted over several decades have shown that the freeze-thaw cycles are a process of energy input and output in soil, which help drive the formation of soil structure, through water expansion by crystallization and the movement of water and salts by thermal gradients. However, most of these studies are published in Russian or Chinese and are less accessible to international researchers. This review brought together a wide range of studies on the effects of freezing and thawing on soil structure. The following findings are summarized: i) soil structure after freeze-thaw cycles changes considerably and the changes are due to the mechanical fragmentation of soil coarse mineral particles and the aggregation of soil fine particles; ii) the particle size of soil becomes homogeneous and the variation in soil structure weakens as the number of freeze-thaw cycles increases; iii) in the freezing process of soil, an important principle in the variation of soil particle bonding is presented as: condensation → aggregation → crystallization; iv) the freeze-thaw cycling process has a strong effect on soil structure by changing the granulometric composition of mineral particles and structures within the soil. The freeze-thaw cycling process strengthens particle bonding, which causes an overall increase in aggregate stability of soil, showing a process from destruction to reconstruction.     

地形和土壤/土地利用空间聚合对径流和输沙量影响的AnnAGNPS模拟

为进一步揭示分布式水文模型子流域划分对径流和输沙量模拟的影响,以东南沿海桃溪流域为研究区,构建日尺度产流产沙的AnnAGNPS模型,基于9种不同临界源面积(critical source area,CSA),分析了不同子流域划分对输入参数空间聚合的影响,并设置7种组合情景,分别从年和日尺度,定量区分了地形与土壤/土地利用参数的空间聚合对产流产沙过程的影响。结果表明:1)随着CSA取值的增加,地形、土壤和土地利用类型在空间上存在明显的聚合。2)土壤/土地利用参数空间聚合导致年平均径流量和输沙量减少,且对输沙量影响更显著;地形参数的空间聚合导致年输沙量减少,但对年平均径流量无显著影响。3)地形参数的空间聚合造成的洪峰流量增加、峰现时间提前,是影响日径流过程变化的主要因素。4)土壤/土地利用参数的空间聚合对多年平均最大1 d、连续最大5 d输沙量的影响随着聚合程度的增加而显著下降,而地形参数的空间聚合造成日输沙过程峰值的出现时间提前。