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991.
Marita Lübke-al Hussein 《Archives Of Phytopathology And Plant Protection》2013,46(2):125-155
In the years 1995 to 1997, following recultivation activities, investigations refering to the colonisation by ground beetles were lead through at four sites in the open-cast mining area Königsaue by means of pitfall traps. Altogether 74 species could be proved, 19% of these species are considered as endangered. The occurrence of the tiger beetle Cicindela arenaria viennensis is remarkable for nature conservation reasons, because this species is threaten by extinction in Germany. The most frequent species in the exhausted open-cast mining area were Calathus ambiguus and Bembidion femoratum . On a site nearly without any vegetation Amara fulva belonged to the dominant species. Species- and dominance-identities between the ground beetle communities of the four sites were low. Also the species turnover between the years of investgation was relatively high. A Benjes-hedge, which was planted in 1996, was investigated additionally. Pitfall trap catches within stands of various crops (winter wheat, summer wheat, maize, peas, sugar beet) nearby the open-cast mining area were carried out in 1995 to 1997 as well. The fields were treated conventionally on tschernosem soils and peaty soils. 67 species of ground beetles were registrated in the fields. The results with regard to species composition and dominance structure resembled those which had been obtained in former investigations lead through near Halle (Saale) and Obhausen (Querfurter Platte). On the peaty soils Dyschirius globosus was very numerous, whereas it was not found on the other fields. An extremly high activity density of ground beetles with more than 20 individuals per day and pitfall trap could be observed in a sugar beet field near Schadeleben. Additional investigations on field edges at another site were realized in 1996. As a whole in the cause of this research 101 species of ground beetles could be proved in the district Aschersleben-Staáfurt, among these many endangered species. 相似文献
992.
G. Elsayed 《Archives Of Phytopathology And Plant Protection》2013,46(16):1534-1549
Allelochemicals are storing in different location in plant tissues as inactive form. Number of identified compounds may now exceed 100,000. Environmental factors have an effect on allelochemicals concentration in plants. Many allelochemicals classified as toxins or deterrents for herbivorous insects. Allelochemicals play a major role in feeding or ovipositing stimulants for some specialist insects. Consumption and assimilation of herbivorous insects had affected by the type of allelochemicals in host plants. Allelochemicals have an acute or chronic toxicity on herbivorous insects. Most specialist herbivorous insects rely heavily of ingested plant allelochemicals. Plant allelochemicals may influence an insect's susceptibility to pathogens such as bacteria, fungi and nematode. Specialists herbivorous insect can be using the allelochemicals in their host plants as protection against natural enemies. Some herbivorous insects are synthesising the aggregation, attracting, alarm or mating pheromone from the allelochemicals in their host plants. 相似文献
993.
Gamal E. S. Abo El‐Ghar Abd El‐Ghany M. EL‐Sayed Anwar E. El‐Shiekh Hosny S. A. Radwan 《Archives Of Phytopathology And Plant Protection》2013,46(6):531-543
A small‐plot tests were conducted on cowpea, Vigna ungiculata (L.) Walp, to determine the effectiveness of 14 selected insecticides representing four insecticide classes (organophosphates, carbamates, pyrethroids, and insect growth regulators, IGRs), and four insecticide/IGR mixtures on cowpea insect pests and its effects on certain beneficial insects. By day 3 after treatement, the insecticides phenthoate, isoxathion, cyanophos, carbaryl, and cypermethrin used at sub‐recommended rates reduced the leafhopper, Empoasca spp., populations by >83% than those in the control. On that day, all insecticide treatments significantly reduced the cowpea aphid, Aphis craccivora, numbers below that of the control. The prothiofos, isoxathion, pirimicarb, and fenpropathrin treatments provided continuing control to both leafhoppers and aphids through day 21 after spraying. It seems that most insecticide treatments were not effective in whitefly, Bemisia tabaci, control. The best control of the whitefly immatures was obtained by day 3 after spraying in plots received thiodicarb (76%) and fenpropathrin (60%). All selected insecticides and rates used had very low residual effect against B. tabaci immatures. By day 3 posttreatment, the carbaryl (2.02 kg/ha) caused completely protection for cowpea pods frMw blue pea butterfly, Lampides boeticus, larvae. The IGRs, flufenoxuron and Dowco‐439, applied alone and those applied in mixtures with insecticides, carbaryl/teflubenzuron, chlorpyrifos/XRD‐473, and methomyl/ flufenoxuron, exhibited satisfactory control (>81%) to butterfly larvae on day 7 posttreatment. All treatments did not exhibit a considerable residual activity against L. boeticus larvae through 2–3 weeks followed spray. Most insecticides applied at the higher rates used significantly reduced the numbers of limabean pod borer, Etiella zinckenella, larvae found in cowpea pods collected on day 7 after application. The IGRs, flufenoxuron and Dowco‐439, applied alone, at 0.119 kg/ha, or in mixtures, methomyl/flufenoxuron (0.167 kg/ha) and chlorpyrifos/Dowco‐439 (0.911 kg/ha) caused >73% control of E. zinckenella larvae through day 21 posttreatment. The best control of cowpea weevil, Callosobru‐chus spp., adults (>83%), on day 3 after spraying, was obtained in treatments of cyanophos (1.19 kg/ha), prothiofos (1.43 kg/ha), flufenoxuron (0.119 kg/ha), and chlorpyrifos/Dowco‐439 (0.911 kg/ha). The IGR flufenoxuron applied alone or in mixture, methomyl/flufenoxuron (0.164 kg/ ha) exhibited satisfactory residual activity against Callosobruchus adults through day 21 posttreatment. Percentage seed damage by the larvae of cowpea weevils was significantly lower in most treatments than that of control. Populations of insect predators found in all treated plots were extremely reduced than those found in untreated plots. By day 21 after spraying, the IGRs flufenoxuron, XRD‐473, and Dowco‐439, applied at the low rate of 0.071 kg/ha, seemed to be less effect against insect predators than other insecticides used. 相似文献
994.
Ruparao T. Gahukar 《Archives Of Phytopathology And Plant Protection》2013,46(17-18):956-978
AbstractCastor (Ricinus communis L.) cultivation is generally cost-effective and profitable for small and marginal farmers in India. However, crop productivity is affected by the damage from pests and plant pathogens. From seedling till capsule harvesting, leaf sap-sucking insects and mites, defoliators, capsule feeding insects; bacterial and fungal diseases and root-knot nematodes attack the crop at various stages of growth and deteriorate plant health. Currently, synthetic pesticides are being applied extensively. Considering side effects of chemicals, other control measures are considered in this review. Findings of greenhouse and the field trials are discussed, and the efficient, economic and eco-friendly management has been elaborated. 相似文献
995.
Dr. Siegfried Richter Dr. Fernando Caceda 《Archives Of Phytopathology And Plant Protection》2013,46(5):409-418
From the position of trophical niche concept, the process of forming of an infestation spot of the winter pine shoot moth in a space of a pine stand as well as the process of degradation of this spot was studied. It was shown that the process begins with the emergance of separate microspots in a stand. With increasing age of the affected stand, the area of these microspots grows, and they unite themselves in lager ones together with growing pest density. The process of growth of both the area and the density continues to an age of 15 years of the pine stands. After that, the reverse process of degradation begins when the area and density decreases. On all the stages of the process, a distribution of density of the pest attacks on trees has contagious character, and stabilisation of an affected ecosystem is finished at the age of 20–30 years. 相似文献
996.
Mojtaba Ghane Jahromi Ali Asgar Pourmirza Golam Reza Sadeghi Seyed Ali Hoseini 《Archives Of Phytopathology And Plant Protection》2013,46(5):526-533
In this research, adults of Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) were exposed to various air pressures solely (first phase) and air pressures together with acrolein (second phase) in various durations and mortality rates were determined. Complete mortality of T. castaneum was obtained at 1, 3 and 6 h after exposure to 10, 30 and 50 mmHg, respectively. R. dominica showed 96.25% and 60% mortality during 3 and 10 h exposed to 10 and 30 mmHg, respectively. Percentage mortality of the insects in second phase was significantly higher than the rate in first phase. T. castaneum was more susceptible than R. dominica in the both phases. 相似文献
997.
Shaaban Abd-Rabou 《Archives Of Phytopathology And Plant Protection》2013,46(18):2157-2175
Hemipterous insects are one of the important pests that attack different economic plants. A study was conducted to evaluate the biological control potential of these pests by augmentation with parasitoids, such as Microterys flavus (Howard), Metaphycus lounsburyi Howard (Encyrtidae), Encarsia sophia (Girault and Dodd), Coccophagus scutellaris (Dalman), Aphytis melinus DeBach (Aphelinidae) and Aphidius ervi Haliday (Braconidae). All the species were mass reared and monthly releases were made in fields of citrus, olive, tomato, sugar cane, mango and squash during each of 11 consecutive years (1999–2009). About 5,830,000 individuals of M. flavus, M. lounsburyi, E. sophia, C. scutellaris, A. melinus and A. ervi were released in the fields of Gharbiya, Marsa Matrouh, Daqahlyia, Qena, Qalyubiya and Behira governorates in Egypt on citrus, olive, tomato, sugar cane, mango and squash which were naturally infested by Ceroplastes floridensis Comstock, Saissetia oleae (Olivier) (Coccidae), Bemisia tabaci (Gennadius) biotype Q (Aleyrodidae), Pulvinaria tenuivalvata (Newstead) (Coccidae), Aulacaspis tubercularis (Newstead) (Diaspididae) and Aphis craccivora Koch (Aphididae), respectively. Population of the parasitoids and parasitism increased in field plots where releases were made when compared with where no releases were made. The maximum rate of parasitism reached 61.4, 92.1, 45.7, 59, 91 and 55.2% in the field treatment where releases were made, while parasitism peaked at 8.2, 13.5, 6, 2, 16 and 17.5% where no releases were made. The populations of M. flavus, M. lounsburyi, E. sophia, C. scutellaris, A. melinus, A. ervi were significantly correlated with the populations of C. floridensis, S. oleae, B. tabaci, P. tenuivalvata, A. tubercularis and A. craccivora during the field seasons. Additional parasitism was caused by natural infestations of Metaphycus helvolus (Compere) and M. lounsburyi (Howard) (C. floridensis), Scutellista cyanea (Motschulsky) (S. oleae), Encarsia lutea (Masi) and Eretmocerus mundus (Mercet) (B. tabaci biotype Q), Encarsia citrina (Craw) (A. tubercularis) and Aphelinus demyaati Abd-Rabou (A. craccivora). These observations enhance the understanding of the usefulness of these parasitoids after augmentation in the field. 相似文献
998.
T.E. Abd El-Wahab I.M.A. Ebadah Y.A. Mahmoud 《Archives Of Phytopathology And Plant Protection》2013,46(6):677-685
The present investigation aimed to identify the insect pollinators and the efficiency of honeybees in pollination of anise plant during flowering periods of 2008 and 2009 seasons at Assiut Governorate, Egypt. Obtained results indicated that the total insect counts attained 11 species, belonging to four orders; Hemiptera (one species), Coleoptera (two species), Diptera (five species) and Hymenoptera (three species). Honeybees were the most abundant of hymenopterous insects during anise flowering and the daily peak activities were detected between 12.00 noon and 2.00 p.m. for the two seasons. Regarding the effect of prevailing air temperature and relative humidity percentage (RH%) on the occurrence of insect pollinators, it is clear that the effects of the two factors were moderate in the two seasons. Also, the results showed a significant effect of open pollination on the seed yield/feddan (1024.12 kg) followed by honeybees pollination (781.55 kg), while insect exclusion recorded the lowest value (300.24 kg). 相似文献
999.
In the present study, the diversity of rumen methanogens in crossbred Karan Fries cattle was determined by constructing 16S rRNA and mcrA (methyl coenzyme-M reductase α subunit) gene libraries using specific primers. All thirteen OTUs or phylotypes from 16S rRNA library clustered with order Methanobacteriales, twelve of which aligned with Methanobrevibacter spp., whereas one OTU resemble with Methanosphaera stadtmanae. Out of eighteen OTUs identified from mcrA gene library, fifteen clustered with order Methanobacteriales, two resemble with Methanomicrobiales and remaining one grouped with Methanosarcinales. These results revealed that Methanobrevibacter phylotype was predominantly present in Karan Fries crossbred cattle fed on high fibrous diet containing wheat straw. Compared to 16S rRNA gene, mcrA gene OTUs clustered in three orders providing better insights of rumen methanogens diversity in cattle. 相似文献
1000.
ABSTRACTFlagship species play an important role in promoting nature conservation. However, although the significance of invertebrates in biodiversity and ecosystem services is undisputed, they are rarely used as flagship species. A focused approach to better understand the drivers of differences in attitudes toward invertebrates, and insects in particular, would be helpful for selecting and establishing insects as flagship species, especially in a local context for local conservation purposes. Using a standard questionnaire, a total of 363 children, predominantly aged 10 to 12 years, were asked about their attitudes toward 18 invertebrate species indigenous to Switzerland. The species, 14 insect species and four other invertebrates, were individually presented in a color photograph without any background information. Based on ordinal regression models, the survey revealed substantial affinity rating differences across the invertebrates selected. Gender, species knowledge, preferred leisure activities, and family membership of a nature protection organization proved to be significant predictors for children's attitudes in general, and for some specific species in particular. Additionally, existing species knowledge was analyzed and was found to neither depend on school location (urban/rural) nor on gender. The authors propose the inclusion of local invertebrates and species knowledge in the curriculum in early years at primary school while applying teaching methods that allow for real-life experience. 相似文献