黄杨绢野螟生物学特性研究

摘要本文阐述了黄杨绢野螟[Diaphania perspectalis(Walker)]在上海地区年发生3代,并以3～4龄幼虫在黄杨木叶片上结苞越冬。翌年3月中下旬开始活动为害;经过2个世代后,第三代幼虫于9月中旬起陆续结茧越冬。同时对该虫的各虫态发育历期、生物学特性等进行了研究,为指导防治提供依据。     

Mechanisation of organic fertiliser spreading,choice of fertiliser and crop residue management as solutions for maize environmental impact mitigation

The environmental impact of crop production is mainly related to fossil fuels consumption and to fertilisers application. Emissions arising from the spreading of organic and mineral fertilisers are important contributors for impact categories such as eutrophication and acidification. The choice of the fertilisers and of the spreading techniques as well as the crop residues management can deeply affect the environmental impact related to crop cultivation.In this study, seven scenarios describing fertilising schemes characterised by different organic and mineral fertilisers and by different mechanisation were compared. The aim is to evaluate, using the Life Cycle Assessment (LCA) method, how the environmental performances of grain maize production were affected by these different fertilisers schemes. The study was carried out considering a cradle to farm gate perspective and 1 t grain maize was selected as functional unit. Inventory data were collected on a farm located in Po Valley (Northern Italy) during year 2013 and were processed using the composite method recommended by the International Reference Life Cycle Data System (ILCD). The compared scenarios involved organic and mineral fertiliser distribution and were: pig slurry incorporation after >3 days after spreading (BS), fast pig slurry incorporation within 2 h from spreading (AS1), direct soil injection of pig slurry (AS2), pig slurry incorporation (after >3 days) with straw collection (AS3), digestate spreading instead of pig slurry (after >3 days) (AS4), only mineral fertilisers (i.e. urea and superphosphate) distribution (AS5) and only mineral fertilisers (i.e. calcium ammonium nitrate and superphosphate) distribution (AS6).The results were not univocal, since climate and soil conditions as well as physical and chemical fertiliser characteristics differently affected the environmental load, especially for particulate matter formation, terrestrial acidification and terrestrial eutrophication impact categories. AS1 and AS2 showed the most beneficial results for these impact categories (between ↙67% and ↙73% respect to worst scenario). AS6, on the opposite, showed the highest environmental impact for those impact categories mainly affected by energy and fossil fuel consumption (climate change, ozone depletion, human toxicity with carcinogenic effect, particulate matter, freshwater eutrophication, freshwater ecotoxicity and mineral, fossil and renewable resources depletion), categories on which AS3 and AS4 were the best solutions. AS3 was the most impacting for terrestrial acidification and eutrophicationA sensitivity analysis was carried out varying grain maize yield (mostly affected: marine eutrophication) and ammonia volatilisation losses due to organic fertilisers (mainly affected: terrestrial acidification and eutrophication).The achieved results can be useful for the development of ⬓spreading rules⬽ that drive the application of organic fertilisers in agricultural areas where there is an intense livestock activity.     

菱传粉生物学研究

以6 个菱品种为试材,对花器形态特征、群体花期及单花开花动态、开花时间、柱头可授性、花粉活力、杂交指数 及传粉形式等进行观察测定。结果表明：菱花单生,两性,单花花期15 h,群体花期在5～10 月,盛花期在7～8 月;不同 品种在一天中的开花高峰期存在差异;柱头可授期主要在萼片开裂后2 h 内,结实率在50% 以上;花粉在自然授粉条件下活 力可保持7.5 h;以自花授粉为主,同时存在一定程度的无融合生殖和少量异花授粉。     

Using process-based modelling to analyse earthworm life cycles

To understand the life cycle of an organism, it is important to understand the physiological processes that govern growth and reproduction. In this paper, we re-analyse a life-cycle data set for the earthworm Eisenia veneta, using a process-based model. The data set comprises measurements of body size and cocoon production over 200 days, at two temperatures (15-25 °C) and two densities (five and 10 worms per container, but with the same worm:soil weight ratio). The model consists of a set of simple equations, derived from Dynamic Energy Budget (DEB) theory. The dynamics of growth and reproduction are simultaneously described by the model, using very few parameters (five parameters for four curves). This supports the use of this model for efficient analysis of earthworm life-cycle data, and to interpret the effects of stressors. However, there was considerable inter-individual variation in the response, hampering the interpretation of the temperature and density effects. A temperature increase corresponded to an increase in the rate constants for growth and reproduction (with the same factor), without affecting the other parameters, as expected from DEB theory. Changing the earthworm density hardly affected the growth curves, but had an unexpected effect on reproduction: at higher densities, the worms start to produce cocoons at a larger body size and the maximum reproduction rate was lower. This study confirms the use of DEB as a reference model for earthworms, and using this model, we can recognise that temperature has a predictable effect on the life cycle of E. veneta. Furthermore, this analysis reveals that the effects of density are less clear and may involve a change in energy allocation that requires further study.     

Are survival and reproduction of Enchytraeus albidus (Annelida: Enchytraeidae) at risk by feeding on Bt-maize litter?

Enchytraeids are saprophagous soil organisms, appearing in high abundances and contributing to ecological processes within the soil. For decades they have been used as model species for biological research. In the framework of research on genetically modified plants, however, they have not been considered to date. Following the ISO/DIS guideline, survival and reproduction of Enchytraeus albidus, fed with diets containing Bt-maize (N4640Bt Cry1Ab, DKC5143Bt Cry3Bb1) leaf material were analysed. For comparison, diets with the corresponding untransformed near-isolines (N4640, DKC5143) were examined. Additionally a high quality control diet (oat flakes) was included. Survival and reproduction showed no significant differences between the Cry3Bb1 treatment and the treatment with the untransformed counterpart. For the Cry1Ab treatment survival was significantly higher than for the treatment with the corresponding near-isoline. In contrast, reproduction was significantly lower for the Cry1Ab treatment compared to that for the isoline. For the Cry3Bb1 treatment, no effect was shown on survival or reproduction. For the Cry1Ab variety and its untransformed counterpart, a contrasting result was detected, which is unlikely to be caused by the Bt-protein but rather by differences in other plant components. Overall survival and reproduction were highest for the control.     

小麦光周期基因TaCO9-1A的克隆、功能标记开发及其与冬春性关系的研究

光周期是植物从营养生长转为生殖生长的重要影响因子,CO(constans)基因在模式植物拟南芥(Arabidopsis thaliana)的光周期途径中起重要作用。本研究利用同源克隆技术从普通小麦(Triticum aestivum L.)宁春4号中克隆了CO同源基因Ta CO9-1A(Gen Bank登录号:KM236233)的g DNA(genomic DNA)及c DNA(complementary DNA)。Ta CO9-1A的全长编码区(coding sequences,CDS)为876 bp,编码291个氨基酸,含有CO-like蛋白家族典型的CCT结构域,但不含B-box结构域;系统进化分析表明,Ta CO9-1A蛋白与水稻(Oryza sativa L.)Ghd7及大麦(Hordeum vulgare L.)Hv CO9位于同一分支;蛋白质空间结构分析表明,其CCT结构域的NF-YA2区域较为保守;Ta CO9-1A原核表达蛋白分子量为31 k D,与预测结果一致;实时荧光定量PCR结果显示,Ta CO9-1A在普通小麦抽穗期的根、茎、叶及幼穗均有表达,但根部表达量较低,相对表达量依次为叶茎幼穗根。比较该基因在冬春性不同品种中的核酸序列发现,冬性品种第二外显子存在6个碱基的缺失,针对该差异开发了分子标记,在25份冬春性不同的小麦品种中扩增出511和517 bp两种带型,分别与这些品种的冬春性及在杨凌地区两年的抽穗及开花时间早晚显著相关。本研究结果表明,Ta CO9-1A在小麦春化作用和光周期途径中扮演着重要角色,为研究小麦光周期途径和春化作用途径提供了基础资料,有助于揭示Ta CO9-1A调控小麦冬春性及成熟期的分子机理。     

The ecology of extinction: population fluctuation and decline in amphibians

Even among widespread species with high reproductive potentials and significant dispersal abilities, the probability of extinctions should be correlated both with population size variance and with the extent of population isolation. To address how variation in demographic characteristics and habitat requirements may reflect on the comparative risk of species decline, I examined 617 time series of population census data derived from 89 amphibian species using the normalized estimate of the realized rate of increase, ΔN, and its variance. Amphibians are demonstrably in general decline and exhibit a great range of dispersal abilities, demographic characteristics, and population sizes. I compared species according to life-history characteristics and habitat use. Among the populations examined, census declines outnumbered increases yet the average magnitudes for both declines and increases were not demonstrably different, substantiating findings of amphibian decline. This gives no support for the idea that amphibian population sizes are dictated by regimes featuring relatively rare years of high recruitment offset by intervening years of gradual decline such that declines may outnumber increases without negative effect. For any given population size, those populations living in large streams or in ponds had significantly higher variance than did populations of completely terrestrial or other stream-dwelling amphibians. This could not be related to life-history complexity as all the stream-breeding species examined have larvae and all of the wholly terrestrial species have direct development without a larval stage. Variance in ΔN was highest amongst the smallest populations in each comparison group. Estimated local extinction rates averaged 3.1% among pond-breeding frogs, 2.2% for pond-breeding salamanders, and negligible for both stream-breeding and terrestrial direct-developing species. Recoveries slightly exceeded extinctions among European pond-breeding frogs but not among North American pond-breeding frogs. Less common species had greater negative disparities between extinctions and recoveries. Species with highly fluctuating populations and high frequencies of local extinctions living in changeable environments, such pond- and torrent-breeding amphibians, may be especially susceptible to curtailment of dispersal and restriction of habitat.     

西花蓟马孤雌产雄生殖繁育的后代种群生命表的建立

孤雌生殖是西花蓟马(Frankliniella occidentalis)繁殖的一种重要方式。前期研究发现,西花蓟马在高温下,雌性的存活率远大于雄性。为探究高温处理后仅有雌性西花蓟马孤雌产雄的情况下其后代建立种群的可能性,试验设定:高温(45℃,2 h)处理西花蓟马单个雌性个体,分别进行孤雌产雄生殖后,雄性子代(F1代)与其母系回交产生F2代;高温(45℃,2 h)处理西花蓟马多个雌性个体,进行孤雌产雄生殖后,雄性子代(F1代)与亲代多个雌性个体共存情况下进行交配产生F2代。两组处理模式下建立F2代实验种群生命表。结果表明,上述两种处理模式,母代雌性个体与子代雄性个体交配后均可产生后代,雄性F1代与其母系回交产生的F2代的雌雄性比为1.05∶1;与亲代多个雌性个体共存下交配产生的F2代性比为1.55∶1。雄性F1代与其母系回交产生的F2代的平均单雌产卵量(F)和内禀增长率(rm)显著小于与亲代多个雌性个体共存下交配产生的F2代(P0.05);各龄期的平均发育历期、平均产卵前期和平均总产卵前期2个繁殖力参数以及净生殖率(R0)、平均世代周期(T)2个种群参数,前者则比后者长(P0.05);另周限增长率(λ)两者之间无显著差异。研究表明西花蓟马在孤雌产雄状态下仍然可以在短期建立种群,具有较强的抗高温能力和繁殖能力,为其成功入侵奠定了生态学基础。     

秸秆沼气化发电技术生命周期评估及经济分析

该研究基于生命周期评价方法和时间价值动态分析方法对沼气直燃发电技术、沼气燃料电池发电技术作可行性分析,并与燃煤发电技术相比,旨在综合评估三种发电技术在环境和经济上的特点,为发电方式选择提供参考依据。结果表明：沼气燃料电池发电技术环境效益最佳,总环境影响负荷为8.55×10-4,沼气直燃发电技术总环境影响负荷为2.15×10-2,两者相较于燃煤发电（2.97×10-1）的减排量分别为99.71%和92.76%。在经济上,沼气直燃发电技术的投资回收期最短（12.03 a）,运营期净现值可达1 361 246 Yuan/MW;其次是燃煤发电技术（14.5 a）,净现值为423 933 Yuan/MW;沼气燃料电池发电技术动态回收期>20 a且未实现盈余。说明沼气直燃发电技术在近期内将仍是替代燃煤发电的最佳发电技术之一。