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71.
It is predicted that dryland salinity will affect up to 17 Mha of the Australian landscape by 2050, and therefore, monitoring the health of tree plantings and remnant native vegetation in saline areas is increasingly important. Casuarina glauca Sieber ex Spreng. has considerable salinity tolerance and is commonly planted in areas with a shallow, saline water table. To evaluate the potential of using the nitrogenous composition of xylem sap to assess salinity stress in C. glauca, the responses of trees grown with various soil salinities in a greenhouse were compared with those of trees growing in field plots with different water table depths and groundwater salinities. In the greenhouse, increasing soil salinity led to increased allocation of nitrogen (N) to proline and arginine in both stem and root xylem sap, with coincident decreases in citrulline and asparagine. Although the field plots were ranked as increasingly saline-based on ground water salinity and depth-only the allocation of N to citrulline differed significantly between the field plots. Within each plot, temporal variation in the composition of the xylem sap was related to rainfall, rainfall infiltration and soil salinity. Periods of low rainfall and infiltration and higher soil salinity corresponded with increased allocation of N to proline and arginine in the xylem sap. The allocation of N to citrulline and asparagine increased following rainfall events where rain was calculated to have infiltrated sufficiently to decrease soil salinity. The relationship between nitrogenous composition of the xylem sap of C. glauca and soil salinity indicates that the analysis of xylem sap is an effective method for assessing changes in salinity stress in trees at a particular site over time. However, the composition of the xylem sap proved less useful as a comparative index of salinity stress in trees growing at different sites.  相似文献   
72.
Zusammenfassung Nach einem kurzen Überblick über die gesetzlichen Grundlagen für die Durchführung der Pflanzenbeschau wird über die Ergebnisse der Kontrollmaßnahmen bei der Einfuhr von Pflanzenerzeugnissen (Getreide) nach Berlin (West) berichtet. Von 1980 bis 1985 wurden insgesamt mehr als 700 000 Tonnen Weizen, Braugerste, Roggen, Hafer, Sonnenblumenkerne, Hirse und Erdnüsse aus 12 europäischen, amerikanischen und afrikanischen Ländern eingeführt, davon mehr als 99% allein aus der DDR.Die Importe aus der DDR waren im Durchschnitt zu knapp 1% mit Vorratsschädlingen befallen, und zwar mit dem Reiskäfer (Sitophilus oryzae L.), dem Gemeinen Kornkäfer (Sitophilus granarius L.), Leistenkopfplattkäfern (Cryptolestes spp.), dem Amerikanischen Reismehlkäfer (Tribolium confusum Duv.) und dem Rotbraunen Reismehlkäfer (Tribolium castaneum Hbst.).
Stored products activities of the plant protection office Berlin. The inspection of imported stored products from 1980 to 1985
A brief survey is given about the legal basis for the inspection of stored products (cereals) imported to Berlin (West). This follows a report about the results of those controls. From 1980 to 1985 more than 700,000 tons of wheat, barley, reye, oats, sunflower seeds, millet and peanuts were imported from 12 European, American and African countries, more than 99% of them from the GDR.On average about 1% of the imports from the GDR were infested by stored product pests; there were rice weevil (Sitophilus oryzae L.), grain weevil (Sitophilus granarius L.), grain beetles (Cryptolestes spp.), confused flour beetle (Tribolium confusum Duv.) and red flour beetle (Tribolium castaneum Hbst.).


Mit 2 Abbildungen und 3 Tabellen  相似文献   
73.
74.
Journal of Pest Science - Slugs are a serious pest of cereal crops, and recent emphasis in slug pest management has shifted from solely chemical towards integrated approaches. The objective of the...  相似文献   
75.
Neonatal mortality rate (NMR) may be affected by maternal physical condition, anesthesia, and uterine incision or en-bloc neonate removal. The association of selected factors with number of dogs with dead puppies at hospital discharge was evaluated using 78 records. Data obtained at admittance for emergency cesarean section included: age, small or large body size, rectal temperature, packed cell volume, serum total protein, blood urea nitrogen, glucose, puppy in pelvic canal, and heart rate. Administration of opioids, propofol, alfaxalone, isoflurane, and sevoflurane, and anesthesia/surgical times and surgical technique were evaluated using Fisher’s exact tests. There were 238 live puppies and 38 dogs had 58 dead puppies; the NMR was 19.6%. Mortality was associated with puppy in the pelvic canal (P = 0.003) and duration of anesthesia > 80 minutes (P = 0.029). Age > 8 years (P = 0.054) and induction time to start of surgery > 30 minutes (P = 0.17) may be associated with mortality. Expedient cesarean section with obstructive dystocia and an induction time to start of surgery < 30 minutes are important for puppy survival.  相似文献   
76.
Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes).During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for “estrildid finches”).  相似文献   
77.
The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy.  相似文献   
78.
Abstract. Four experimental diets were formulated to resemble practical rainbow trout, Salmo gairdneri Richardson, grower feeds based on medium and moderate lipid inclusions of 10 and 14% (standard energy levels) to relatively 'high energy' diets containing 18 and 22% lipid respectively. Each of these diets was isonitrogenous with a defined protein content of 42%. During a 10-week growth trial period, juvenile rainbow trout of initial mean weight of 10g were fed each ration to satiation. At the end of the study, there was a significant gain (P> 0.05) in the mean live weights of fish receiving the higher energy diets associated with improved feed conversion ratio (FCR) and net protein utilization (NPU). Although there was a declining trend in voluntary food intake relative to body weight with increasing dietary lipid content, this was insufficient to prevent greater deposition of body fat.
The results are discussed in relation to practical trout feeds in order to achieve a desired growth performance and acceptable body composition with intensive feeding regimes.  相似文献   
79.
[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal ratio of both acaricides were determined by means of co-toxicity factors and co-toxicity coefficients(CTC).[Result]At 24 h post-treatment,the LC50values of diafenthiuron and fenbutatin-oxide against T.cinnabarinus female adults were 154.67 and 93.26 mg/L,respectively,and the synergistic mass ratios of diafenthiuron and fenbutatin-oxide ranged from 1:0.06 to 1:0.87,and the optimal diafenthiuron-to-fenbutatin-oxide ratio was 1:0.39 with the LC50and CTC of 67.87 mg/L and 188.93(CTC significantly above 100 strongly indicated synergism),respectively,and the toxicity relative to diafenthiuron and fenbutatin-oxide was 2.28 and 1.37 times,respectively.[Conclusion]The joint acaricidal action of diafenthiuron and fenbutatin-oxide strongly indicates synergism.These findings proved scientific theoretical basis for mixing diafenthiuron and fenbutatin-oxide to control spider mites and developing a new synergisic acaricide.  相似文献   
80.
  1. High elevation lakes are extreme ecosystems and serve as sentinels of various global changes.
  2. An expedition to Volcán Llullaillaco in 1996 discovered an unstudied high-elevation lake (6,170 m a.s.l.) that probably was formed as a result of the past eruptive events or climatic processes such as glacial retreat in the lake basin.
  3. This article describes an initial physical characterization of the lake and its microbial communities derived from two sampling expeditions in 2013 and 2016.
  4. The microbial community in the lake, with an area between 1.2 and 1.4 ha and a depth of 6.8 m, was dominated by Proteobacteria, Actinobacteria and Haloarchaea. In addition, 26 bacterial isolates were identified within the genera Subtercola, Xylophilus, Rhodanobacter, Mesorhizobium and Pseudomonas.
  5. Lago Llullaillaco is one of the highest recorded lakes in the world, and this study highlights the unique microbial diversity of this aquatic ecosystem and the importance of its preservation to understand the complex biological processes under polyextreme conditions.
  相似文献   
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