黑绒金龟子初步研究

黑绒金龟子为防护林区主要害虫之一, 在东北地区每年发生一代, 以成虫在土中越冬, 越冬成虫4月上旬出土, 4月下旬到5月下旬为发生盛期, 成虫的发生消长和一定温度有关外, 更大程度和降雨量、湿度关系更为密切, 在通常情况下其发生高峰和多雨季节相吻合。成虫食性复杂, 不同饲料对其取食量、产卵量、产卵期有很大影响, 对于榆树叶的取食量最大、产卵量最多、产卵期也最长, 其余树种则次之。幼虫有3龄, 平均第一龄期19.29天, 第二龄期14.96天, 第三龄期31.42天。22—25℃温度范围的土层适合于1—2龄幼虫的活动。老熟幼虫潜入深层化蛹, 蛹期一般为半个月, 羽化后成虫在土中有升降活动, 当年一般不出土, 少数个体虽有出土活动或取食但不交配产卵。黑绒金龟子由于不同发育阶段受到不同温度的影响, 在土层中有不同深度的分布。部分成虫可以经二次越冬, 但第二次越冬后的成虫是否能正常产卵繁殖还有待进一步研究。     

草莓中黄酮类物质的测定以及与抗氧化活性之间的相互关系

报道草莓中黄酮类物质含量的测定方法,并比较了总抗氧化成分与抗氧化活性(DPPH,FRAP)之间的相互关系.黄酮类物质的水解随着HCl浓度和水解时间的不同发生较大的差异,结果表明,总多酚类物质和总黄酮类物质之间有很高的相关关系,总多酚类物质和总黄酮类物质对DPPH有很高的相关关系,而且总多酚类物质和总黄酮类物质对FRAP的相关关系各为r=0.958, P ＜0.05和r=0.936, P ＜0.05,从结果可以推测:草莓体现出很强的抗氧化活性,这与草莓中的总多酚类物质成分密不可分.     

Evaluating drought effect on MODIS Gross Primary Production (GPP) with an eco-hydrological model in the mountainous forest, East Asia

Surface soil moisture dynamics is a key link between climate fluctuation and vegetation dynamics in space and time. In East Asia, precipitation is concentrated in the short monsoon season, which reduces plants water availability in the dry season. Furthermore, most forests are located in mountainous areas because of high demand for agricultural land, which results in increased lateral water flux and uneven distribution of plant available water. These climatic and topographic features of the forests make them more vulnerable to drought conditions. In this study, the eco‐hydrological model (Regional Hydro‐Ecological Simulation System) is validated with various water and carbon flux measurements in a small catchment in Korea. The model is then extended to the regional scale with fine‐resolution remote sensing data to evaluate the Moderate Resolution Imaging Radiometer (MODIS) leaf area index and gross primary productivity (GPP) products. Long‐term model runs simulated severe drought effect in 2001 well, which is clearly shown in the ring increment data. However, MODIS GPP does not capture this drought effect in 2001, which might be from a simplified treatment of water stress in the MODIS GPP algorithm. This study shows that the MODIS GPP products can potentially overestimate carbon uptake specifically during drought conditions driven by soil water stress.     

稀浓度化学药剂对马尾松毛虫越冬幼虫的毒效试验

1959—1960年作者等在江西、湖南等地区配合大面积防治森林害虫之际,开展了DDT等化学药剂对于不同越冬时期的马尾松毛虫幼虫的毒效试验。据野外观察结果,将马尾松毛虫越冬幼虫划分为5个时期。即越冬前活动期、越冬前期、越冬期、越冬后期、越冬后活动期。试验证明:不同化学药剂对越冬松毛虫幼虫的毒效随着不同时期和温度条件而变化。就一般论:DDT的效果,在比较低温(日均温10—20℃)时特别显著;666及敌百虫的效果,在比较高温时(20℃以上)为显著。其中尤以敌百虫为更甚。DDT对不同时期幼虫的毒效大小为:越冬后期>越冬前期>越冬期>越冬前活动期>越冬后活动期≥夏季(4-5龄)幼虫;其中以越冬后期幼虫抵抗力最弱。从原则上论这是施药的最适宜时期,从25% DDT乳剂4,000倍稀释液在越冬后期(2,3月间)施用,毒效可达92%以上,用6,000倍稀释液亦达82%以上。如用γ6%可湿性666,800倍稀释液在越冬前、后期使用,毒效可达70-80%以上。50%敌百虫乳剂在温度20℃以上时(越冬前、后活动期)毒效显著增高。此时如用5,000-6,000倍稀释液喷洒,毒效可达70-80%左右。由此,作者认为:在长江以北,每年发生2代以下的松毛虫地区,可用DDT和666稀释液在越冬前、后期进行防治。长江以南,每年发生2代以上的马尾松毛虫地区,不但可用DDT、666来防治越冬前、后期幼虫;而且在幼树林地内越冬期的幼虫亦可防治。在上述地区内,敌百虫乳剂仅适于在越冬前、后活动期或夏季幼虫期温度较高时使用。就一般论,在越冬前期施用药剂时,如能选定在寒流侵袭之前喷射,效果更为显著。     

Change of Haemolymph Ferritin of Sweet Potato Hornworm, Agrius convolvuli by Heavy Metals

Agrius convolvuli haemolymph ferritin was purified by KBr density gradient ultracentrifugation and anion exchange column chromatography. The 670 kDa ferritin was composed of two subunits of 26 kDa and 31 kDa. It was also shown that the protein had an isoelectric point (pI) of pH 7.4. The N‐terminal amino acid sequences of the two subunits were NH2‐DNXYQDVSLDXSQAXNXL (26 kDa subunit) and NH2‐TQXHVNPVNIQRDXVTMHXS (31 kDa subunit). The sequential analysis showed that they had high similarity to lepidopteran ferritin subunits, S‐ and G‐type, respectively. Using electron microscope, it was observed that the protein had a core whose size was about 7 nm. In the amino acid composition of the protein, Glu (13.22%), Asp (10.43%), Pro (9.69%), Leu (9.63%), Ala (9.55%) and Gly (8.49%) were in relatively high contents while Tyr (1.21%), His (2.58%) and Arg (3.10 %) were in low. It was shown that the amount of ferritin in A. convolvuli haemolymph was increased by injection of eight different heavy metal ions, FeCl₃, HgCl₂, CuSO₄, ZnSO₄, MnCl₂, MgCl₂, CrCl₃ and CdCl₂. Among the ions, Fe³⁺, Hg²⁺, Zn⁴⁺, Mn²⁺ and Cd.²⁺ significantly induced the amount of the protein.     

Longitudinal variation in food sources and their use by aquatic fauna along a subtropical river in Taiwan

1. River food webs rely on two major food sources: autochthonous primary production within the river and allochthonous organic matter transferred to the river. We characterised the consumer communities and assessed the food sources of dominant consumers along a subtropical mountainous river (the Lanyang River of north‐eastern Taiwan) at the catchment scale from the headwater to the estuary using natural abundances of stable carbon and nitrogen isotopes. 2. The downstream transport of fine particulate organic matter (FPOM) was two orders of magnitude greater than that of coarse particulate organic matter (CPOM). Transport of both materials increased from the headwater and reached a maximum in the midstream reach. CPOM composition exhibited a gradual shift from leaves and branches in the headwater, an area characterised by high canopy cover, to algae in the midstream reaches and marsh plants in the downstream reaches. 3. Consumer communities can be classified into two regional categories: the upland category in the headwater and upstream and midstream reaches and the lowland category comprised of samples from the downstream reach and estuary. The upland category revealed a clear and gradual seasonal shift in community composition, but a seasonal shift was not apparent for the lowland category. Nutrient concentrations and water temperature were the main factors explaining longitudinal and seasonal variations. 4. The use of sources of organic matter by dominant consumers along the Lanyang River was primarily determined by their availability. Riparian C₃ plants were the major food sources in the headwater, upstream reach and estuary, but the contribution of periphyton increased in the upper midstream reach where the river flows through an agricultural area. In the lower midstream and downstream reaches, the contribution of riparian C₄ plants became dominant. 5. The trophic transfer of organic materials in the Lanyang River may be influenced by the fast current velocity and by sewage nutrient loading in the river, both of which have important implications for predicting how the functioning of subtropical river food webs will respond to human‐related changes in land use.     

我国森林害虫“松毛虫”综合防治的实践及展望

我国森林害虫的种类很多,其中以松毛虫类为害最严重。松毛虫的种类多,分布广,繁殖力强,猖獗时能食尽松针,引起大面积松林死亡。严重影响绿化成果的巩固及林产品产量和质量的提高。松毛虫体上的毒毛,触人肌肤引起肿痛,也影响人民的健康。 松毛虫猖獗成灾,在我国历史上早有记载,但历代反动统治者,从未重视这一问题,听之任之视为天灾,解放后党和政府重视森林资源的保护和发展,为此从中央到地方建立