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1.
《Journal of Asia》2022,25(2):101897
Chestnuts and walnuts are ones of most important forest products in Korea. However, Conogethes punctiferalis has been increasingly causing economic damages to chestnuts and walnuts. Currently, its management is mainly relayed on aerial application of pesticides. To select pesticides of C. punctiferalis for aerial application, damage rate of chestnut and walnut fruits and death rate of C. punctiferalis were analyzed according to selected pesticides. Experiments were conducted during two years by randomly applying chemical pesticide (i.e., Chlorfluazuron 5 % in 2018 and Thiacloprid 10 % in 2019), organic pesticide (i.e., paraffin oil 8 % + plant extracts (90 %) from Styphnolobium japonicum, Melia azedarach, and Dysphania ambrosioides), and no treatment (i.e., control) into an area which were divided into three from a whole commercial field. All pesticides used in this study could suppress damages of walnuts and chestnuts by C. punctiferalis. However, these pesticides could not kill their larvae inside of fruits. Thus, aerial spraying these pesticides for C. punctiferalis should be applied at optimal timing or slightly earlier than optimal timing. By considering honeybee toxicity, cost, and management efficiency, Chlorfluazuron 5 % was the best as an aerial application pesticide among these three pesticide in this study.  相似文献   

2.
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that could be produced in the second somersault of a double somersault on trampoline using asymmetrical movements of the arms and hips. Lower bounds were placed on the durations of arm and hip angle changes based on performances of a world trampoline champion whose inertia parameters were used in the simulations. The limiting movements were identified as the largest possible odd number of half twists for forward somersaulting takeoffs and even number of half twists for backward takeoffs. Simulations of these two limiting movements were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist at landing after a flight time of 2.0 s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that 3½ twists could be produced in the second somersault of a forward piked double somersault with arms abducted 8° from full adduction during the twisting phase and that three twists could be produced in the second somersault of a backward straight double somersault with arms fully adducted to the body. These two movements are at the limits of performance for elite trampolinists.  相似文献   

3.
In this paper we will summarize some of the important sampling and non-sampling errors with special reference to the mail surveys on migratory game birds and aerial surveys on breeding birds in North America. Where possible, methods for controlling the errors will be indicated.  相似文献   

4.
Two new angular-type pyranocoumarins, namely hyuganin G (1) and hyuganin H (2), were isolated from an ethyl acetate extract of the aerial parts of Angelica furcijuga, together with three known angular-type pyranocoumarins, isoepoxypteryxin (3), isopteryxin (4), and hyuganin E (5). Assignment of the 1H and 13C NMR data of 1 and 2 were achieved via analysis of the DEPT, HMQC, and HMBC spectra. The absolute configurations of 1 and 2 were determined by semi-synthesis from 3.  相似文献   

5.
Adult shore flies were experimentally shown to be aerial vectors for three soilborne plant pathogens: Verticillium dahliae, Fusarium oxysporum f.sp. basilici and Thielaviopsis basicola. Adult insects are attracted to sporulating cultures of the soilborne fungi investigated, as well as infected plant tissues. Shore flies acquired fungal propagules both by ingestion and surface contamination. The minimum acquisition time for propagules of soilborne fungi was 10–20 min and acquisition increased with time to reach 100% frass deposits infestation after 2 h of acquisition. The inoculum potential of the frass deposits was high considering that the number of viable spores deposited by one adult insect in a day was 2.38 × 107, 3.08 × 106 and 8.83 × 106 for V. dahliae, F. oxysporum f. sp. basilici and T. basicola, respectively. Electron microscopy investigation implicated body surface contamination as a means of viable propagule acquisition. Pathogen distribution by adult shore flies was rapid over time at 2.21 cm2 per hour per insect. The area over which the pathogen was distributed by adult shore flies increased with the increase in exposure time. The study showed that adult shore flies are efficient in the dispersal of the soilborne plant pathogen T. basicola.  相似文献   

6.
Adult fungus gnats and moth flies were experimentally demonstrated to function as potential above‐ground vectors for three soilborne plant pathogens: Verticillium dahliae, Fusarium acuminatum and Thielaviopsis basicola. The adult insects externally acquired the conidia of the pathogens after exposure to the cultures as confirmed by scanning electron microscope photography. The intestinal contents and frass deposits of larvae exposed to fungal cultures contained viable fungal propagules. Internally infested larvae developed into internally infested pupae; however, the emerging adults were free of fungal structures. Because of the maintenance of a high level of inoculum on the external body surface and the ability of these adult insects to fly, they can be a significant factor in the dispersal of soilborne fungi in greenhouse agriculture. The rate of dispersal of T. basicola by adult fungus gnats was 1.78 cm2 h?1 per insect and by adult moth flies was 1.17 cm2 h?1 per insect. The area over which the pathogen was dispersed by the adult insects increased with the increase in exposure time. The study demonstrated that adult insects are efficient distributors of soilborne plant pathogenic fungal propagules.  相似文献   

7.
The proximity of a biological control agent and its associated anti-microbial metabolites to pathogens on plant surfaces can determine the outcome of disease control. In this study we investigated whether deficiencies in inoculum deposition and localization could explain the inability of the biological control agent Bacillus amyloliquefaciens strain TrigoCor to consistently control Fusarium head blight in the field, despite producing effective and consistent disease control in greenhouse settings. Using epifluorescent stereomicroscopy and confocal laser scanning microscopy, we visualized the coverage of wheat spike surfaces by Bacillus post-application in greenhouse and field environments, and determined that there are large unprotected areas on wheat spikes sprayed with commercial-scale field equipment, as compared to typical greenhouse applications. Additionally, we found that in conditions of low relative humidity, antifungal compounds produced by Bacillus were not able to diffuse across wheat surfaces in biologically relevant amounts, further suggesting that the inadequate coverage of wheat surfaces by Bacillus could be directly limiting disease control. Bacillus cells were easily rinsed off wheat surfaces within 8 h of application, indicating that rainfastness might be an additional limitation of biological control in field settings. Finally, we observed the inhibition of Fusarium graminearum spore germination by TrigoCor inoculum on wheat surfaces, confirming this as a mode of action for TrigoCor biocontrol. Future optimization efforts for biological control agents applied to above-ground plant parts should focus on enhancing the rainfastness, quantity, and spatial coverage of the inoculum on plant surfaces.  相似文献   

8.
黑龙江省三江平原丹顶鹤的数量分布   总被引:2,自引:0,他引:2  
在地面调查的基础上,我们使用Y-11轻型飞机对黑龙江省三江平原地区的丹顶鹤的数量分布近行了调查,调查时飞行高度80米,航速140公里/小时,续航里程共3748公里。调查结果表明,丹顶鹤在三江平原主要分布在8个地区,其中嘟噜河下游、洪河自然保护区、七星河流域和兴凯湖低地是主要繁殖地,总数量共309只。  相似文献   

9.
细枝木麻黄气生瘤的人工形成邹铧,张忠泽,张成刚,丁鉴,王育英,付莉(中国科学院沈阳应用生态研究所,沈阳110015)ArtificialformationofaerialnodulesonCasuarinacunninghamiana¥ZouHua;...  相似文献   

10.
毛乌素沙地主要飞播植物种群的消长动态   总被引:11,自引:1,他引:10       下载免费PDF全文
 本文讨论了毛乌素沙区3个主要飞播植物种在不同沙丘类型区域飞播后种群盖度的消长动态。研究表明,在与其它植物种混播的情况下,籽蒿在群落中作为优势种或共优种的时间很短,一般在飞播后3~5年内种群盖度达到最大值,然后以不同的速率从播区中退出,播区沙丘越高大,其衰退速率越慢。羊柴在飞播后的前10~15年内种群盖度一直保持着上升趋势,它在播区内作为优势种的时间要比籽蒿长得多,而且以它为优势种的单优群落具有强烈的排它性。花棒由于其散生的习性,飞播后在群落中的优势作用不是很强,一般在飞播后前5年种群盖度呈增长趋势,然后缓慢下降或基本保持稳定。  相似文献   

11.
中华鳖幼体呼吸代谢的初步研究   总被引:8,自引:0,他引:8  
本文利用改装后的Kalabukhov-Skvorstov呼吸器,同时测定了中华鳖在自由潜水状态下的空气呼吸和水呼吸摄氧量。结果表明:在正常生活状态下,中华鳖主要依靠空气呼吸摄氧;水呼吸仅占总呼吸摄氧量为2.68%左右。呼吸摄氧率无显著昼夜变化。  相似文献   

12.
To date, there have been reports mostly about research results of the peony root in comparison to the aerial parts. According to our study, the aerial parts of P.lactiflora showed superior anti-oxidative and pancreatic lipase inhibitory activities than its root. Especially, the water extract and the ethyl acetate fraction of the ethanol extract exhibited potent pancreatic lipase inhibitory activity by 53.11 ± 1.22% and 46.16 ± 1.55% at the same dose of orlistat (62.5 ± 1.27%). The ethanol extract exhibited the best anti-oxidative activity with IC50 of 17.08 ± 0.9 μg/mL, and the ethyl acetate fraction 19.75 ± 0.02 μg/mL, respectively, comparing to the positive control rutin (IC50, 22.66 ± 0.29 μg/mL). From the anti-oxidative and pancreatic lipase inhibitory active fractions three new compounds, monplacphloroside (1), monplachydroxyquinoside (2) and herbacetin-7-O-β-d-sophoroside (3) were isolated along with 19 (4-22) known ones.Compounds, PGG (14), 1-O-methyl-2,3,4,6-tetra-O-galloyl-β-d-glucopyranose (17) and ethylgallate (9) were found to be the strongest antioxidants and pancreatic lipase inhibitors. Monoterpenes, albiflorin R2 (19) and albiflorin (20) were determined for the first time as strong pancreatic lipase inhibitors. The presence of the esterified galloyl moiety, with its increasing numbers or the β-lactone cycle within the molecular structure plays an essential role for the enhancement of the pancreatic lipase enzyme inhibitory activity.  相似文献   

13.
Aerial flycatching — the lightning-fast seizure of flying small birds in the beak of larger, not normally predatory birds, only a few cases of which are treated in the literature — is here described and discussed for white storks (Ciconia ciconia) and crows (Corvidae).Communicated by F. Bairlein  相似文献   

14.
We examined environmental correlates of activity in the Freckled Nightjar (Caprimulgus tristigma), a nocturnal aerial insectivore that is resident year-round in the colder and drier parts of southern Africa. Specifically, we tested the prediction that air temperature (T a), in addition to light availability, is a significant correlate of Freckled Nightjar activity. We found that aerial insect density varied by over three orders of magnitude (from <1.0 to 117.1 insects 1,000 m−3) during the course of the study, and was strongly and positively related to T a. Nightjar activity was also significantly temperature-dependent, with a cessation of activity at T a < 12°C. Consistent with previous studies, we found that activity levels were strongly related to ambient light, with markedly reduced activity levels on dark nights. The average number of Freckled Nightjars encountered per 14.6-km transect was 1.95 ± 2.44 nightjars transect−1 during nights near full moon, but only 0.17 ± 0.61 nightjars transect−1 around new moon. Our study reveals that caprimulgid activity can be significantly influenced by temperature as well as ambient light.  相似文献   

15.
荒漠植物角果藜的地上地下结果性   总被引:7,自引:0,他引:7  
高蕊  魏岩 《云南植物研究》2007,29(3):300-302
对分布于准噶尔荒漠中角果藜(Ceratocarpus arenarius)果实的形态特征、空间位置、发育特性及散布特性进行了比较研究,结果表明:角果藜具有地上地下结果性,地上果实和地下果实在颜色、形状、大小、质量、数量、空间位置、成熟期和散布特性上均有显著差异。角果藜地上地下结果性是植物适应荒漠多变环境所具有的一种特殊的繁殖方式。这种独特的繁殖方式增加了物种在荒漠极端环境中成功生存的机率,保证了物种的顺利繁衍。这是首次在藜科植物中发现的地上地下结果性现象。  相似文献   

16.
Phytochemical investigation of the dichloromethane extract of the dried aerial parts of Corydalis rupestris (Papaveraceae) resulted in the identification of four new isoquinoline alkaloids rupestrines A-D and one known isoquinoline alkaloid, namely, stylopine. The structures of these compounds were characterized by extensive spectroscopic methods including 1D- (1H and 13C) and 2D NMR experiments (COSY, HSQC, HMBC, and NOESY) as well as HRESIMS analyses. In addition, the absolute configurations of rupestrines A-D were determined using modified Mosher’s method. Cytotoxic effects of alkaloids and their interaction with albumin were also investigated in this study.  相似文献   

17.
Synchronously germinating aerial spores of Streptomyces granaticolor were used to study protein activation and expression during the transition from dormant to metabolically active vegetative forms. The first phase of protein activation is associated with the solubility of proteins. Three major chaperones, DnaK, Trigger factor, and GroEL, were identified in spores. Enhancement in rate of protein synthesis during germination was accompanied by the association of TF and DnaK with ribosomes. During germination, the chaperones TF, GroEL, and DnaK undergo reversible phosphorylation. GroEL was phosphorylated on both Ser and Thr, whereas phosphorylation of DnaK and TF was detected on Thr only. A proteomic approach was used to gain more information on protein expression during germination on two types of media differing in the ability of cells to produce antibiotic granaticin. To obtain an overview of the metabolic activity of germinating spores, glycolytic enzymes, enzymes of citric acid cycle, metabolism of amino acids and nucleic acids, and components of the protein synthesis system were identified and analyzed using the proteomic database. The results were deposited on the SWICZ proteomic server and are accessible on http://proteom.biomed.cas.cz.  相似文献   

18.
Microhabitat use and feeding behavior of the rainbowfish Melanotaenia duboulayi (Castelnau) were investigated in a slow-flowing stream adjacent to riparian forest in south-eastern Queensland, Australia. Fish were more abundant in vegetated areas, but did not enter dense Vallisneria beds, where predators were observed. In sunny conditions shoals of juveniles occurred near the water surface feeding floating material on the surface, but larger fish tended to occur at the bottom near submerged vegetation, often utilizing the overhanging aquatic plant community as a refuge and food source. In the middle of the day, juveniles and small fish seemed to show behavioral thermoregulation at the surface in the warmest site. Under cloudy conditions, however, fish of all sizes preferred deeper water. The present study suggests that in still and sunny pools thermal change caused by sunlight influences the microhabitat choice of small fish. A field experiment using a kingfisher model implies that fish swimming at the surface could escape from aerial predators in sunlit conditions by responding to moving shadows, but could not do so under cloudy conditions. Electronic Publication  相似文献   

19.
Aerial surveys have been used to estimate abundance for several wild bird species but its application for wild turkey (Meleagris gallopavo) populations has been limited. We surveyed Rio Grande wild turkey (M. gallopavo intermedia) populations during March 2006 using an R44 helicopter. We used flocks with radio-tagged birds to estimate flock detectability. We also used simulations to evaluate accuracy and precision and examine power to detect trends in population change. We observed that wild turkey flock detectability was 94.7% (74.0–99.9%; 95% CI). Our simulations suggested helicopter surveys would underestimate abundance by about 5.6% (4.6% CV). Surveying 980 to 1,960 km2 (requiring 27 to 55 h of flight time) can provide sufficient power (≥0.80) to detect a 10 to 25% change in abundance over a 4- to 5-year period.  相似文献   

20.
In the takeoff and early flight phase of a twisting somersault, joint coordination is based on feed-forward control whereas in the late stages of the flight phase configuration adjustments are made using feedback control to ensure accurate completion of the movement and appropriate landing orientation. The aim of this study was to use a computer simulation model of aerial movement to investigate the extent to which arm and hip movements can control twist and somersault rotation in the flight phase of a twisting somersault. Two mechanisms were considered for the control of twist in simulated target trampoline movements with flight times of 1.4 s. In the first case a single symmetrical arm adduction correction was made using delayed feedback control based on the difference between the twist rate in a perturbed simulation and the twist rate in a target movement comprising a forward somersault with 1½ twists. Final corrections were made using symmetrical arm abduction and hip flexion to adjust the twist and somersault angles. In the second case continual asymmetrical arm adduction/abduction adjustments were used to remove the tilt from a perturbed full twisting backward somersault using delayed feedback control based on twist angle and angular velocity. The first method was able to cope with perturbations to a forward somersault with 1½ twists providing the feedback time delay was less than 200 ms. The second method was able to correct a perturbed full twisting backward somersault providing the feedback time delay was less than 125 ms.  相似文献   

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