File: Size of this preview: × pixels. Other resolutions: × pixels | × pixels | 1, × Determinacao de danos da cigarrinha-das-pastagens (Deois incompleta) a Brachiaria humidicola E.B. decumbens . Silva, A.B.. Access the full text. Cigarrinhas-das-pastagens, Zulia entreriana (Berg, ) (Homoptera, Cercopidae), no norte do Estado de Minas Gerais. II. Controle de ninfas com inseticidas.
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Thus, postdiapause eggs need 26 d of moisture to ensure initiation of embryonic development in all individuals of a population. Bars represent only the time spent in condition 3. This study investigated responding by exclusionwhich has been demonstrated as a robust behavioral process, passtagens in the selection of an undefined comparison stimulus, when the sample is also an undefined stimulus Proportional mortality of the spittlebug, D.
Empty chorions were excluded. Although many studies show how patterns of climatic variation can influence insect population abundance in the tropics e. For commercial re-use, please contact journals.
Cercopidae in Mexican Pangola pastures. Cages consisted of cylindrical iron frames 0. Related articles in Web of Science Google Scholar. Cohorts with variable numbers of D.
Cigarrinha-das-pastagens – Biofaces – Bring Nature Closer
The average time for egg hatch in all treatments Fig. The proportion of postdiapause eggs starting final embryonic development increased as a consequence of exposure to increasing periods of moisture in condition 1 Fig. Such eggs die when faced with drought conditions, but they were still found in the June-July soil samples. In this work we evaluated mortality rates during three distinct stages of spittlebug development: Environmental factors affecting spittle-bug egg survival pastagenss the dry season in central Brazil.
Cigarrinha das pastagens: by Gracielle Caroline Mari on Prezi
Observations stopped when all surviving nymphs reached the second instar. Dry-season dormancy in eggs of Deois flavopicta Homoptera: Migration may have a role in this dynamics except in some cases, such as outbreaks and local extinction. After the dry season, postdiapause eggs remain quiescent waiting for favorable conditions to hatch Pires et pastagenw.
The ccigarrinha postdiapause eggs resuming embryonic development, parameter A equation 1were observed after 4 d of exposure to moist conditions, and the last diapausing egg resuming embryonic development, parameter B equation 1was observed after 26 d. The volume of the solution utilized was liter ha-1 with sprayer.
If so, these eggs would hatch early reducing the average time in some treatments. In the current ppastagens, we propose a model that explains how different combinations of precipitation and drought periods at the beginning of the rainy season can influence the mortality pastahens eggs in the final embryonic stage and of newly emerged nymphs. This could explain why several authors Milanez et al. The data suggest a lack of pattern related to the geographical position of the traps.
The termination of diapause at the beginning of the rainy season, when the frequency of rain is unpredictable, probably caused the increase of egg mortality in September. Cercopidae on wild and cultivated host species. From these data, we conclude that M. Hostplantand seasonal abundance patterns of some Brazilian Chry-somelidae. At the beginning of September, when the eggs naturally enter the postdiapause or quiescence without any token stimuli Pires et al.
D h until the emergence of nymphs. Proportional mortalities for each instar were compared among the different generations to evaluate the effects of seasonal weather variation. Moisture was provided by adding water ad libitum to the cotton underneath the filter paper. Time taken for eggs of D. All recovered eggs, even those with alterations in color or form, suggesting that they were dead, were included in the sample. The fungus entomopathogenic Metarhizium anisopliae Metsch.
Mixed risk-spreading strategies and the population dynamics of a Brazilian pasture pest, Deois flavopicta. The movement of marked and recaptured populations was monitored with non-toxic fluorescent powder. The cages did not have bottoms and were placed directly over the pasture to allow access to grass for feeding and to soil for oviposition. The mortality rate of around 9.
Predicted mortality of eggs in final stage of em-bryonic development and of newly emerged nymphs of D.
To model the proportion of eggs resuming embryonic development as a function of moisture exposure time, a graph of the accumulated proportion of embryos that resumed development ciggarrinha constructed. Approximately pairs were placed in each of 12 cages randomly distributed over the same pasture from which they were captured.
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Cigarrinhas-das-pastagens Homoptera-Cercopidae em Pqstagens decumhens sob diferentes cargas animais. Modified and acceptance control charts allow a new approach to statistical process monitoring. For each period of moisture exposure, hatching time and egg mortality rates were calculated.
Postdiapause eggs of the spittlebug resuming embryonic development after exposure to moist conditions for different periods. It was verified that the levels of nymphs were reduced after the sprayings of M.