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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To determine the movement and survivorship of each individual during the nymphal stage, the position of each nymph within cages was marked with a small numbered wooden stake. Print Add to your cart remove More searches Search for this title in: Proportional mortalities for each instar were compared among the different generations to evaluate the effects of seasonal weather variation.
Sorokin icgarrinha considered an efficient agent for the biological control of many insects that represent plagues of agriculture. All recovered eggs, even those with alterations in color or form, suggesting that they were dead, were included in the sample.
Cigarrinha-das-pastagens (Pasture planthopper)
We observed only a constant and low rate of mortality in different years. The objective of this research was to evaluate the efficiency of spraying Brachiaria bryzantha pasture with the fungus M.
Resumo Spittlebugs are the main pests of pasture of America Tropical, pasatgens which the genera Deois and Mahanarva stand out. This rate of natural infertility was subtracted from all moisture-exposed treatments to better estimate the proportion of eggs starting final embryonic development Fig.
This study is part of a Ph. The low mortality rates of eggs observed during the middle of the dry season July and August indicate that lack of moisture and warm soil do not preclude outbreaks of D. Nymphal density in each cage was recorded and correlated with mortality estimates. Periods of drought and high temperatures after the beginning of postdiapause development increased embryonic and nymphal mortality.
Cages consisted of cylindrical iron frames 0. Plastic ccigarrinha containing adesive trap were used to monitorate the movement rates.
It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide. Preference performance linkage in the neotropical spittlebug Deois flavopictaand its relation to the phylogenetic constraints hypothesis.
Cigarrinha-das-pastagens (Pasture planthopper) | Project Noah
To estimate the average proportion of natural infertility in the population and the time of exposure to moist conditions required for postdiapause eggs to resume embryonic development, a group of four Petri dishes with 15 eggs each was cas under moist conditions until hatching or death of all eggs.
Predicted mortality of eggs in final stage of em-bryonic development and of newly emerged nymphs of D. Se ensayaron 6 insecticidas para evaluar el grado pastagehs eficiencia en el control de Deois incompleta, principal plaga de los pastos en la Amazonia. Feeding behavior of the spittlebug Deois flavopicta Homoptera: For commercial re-use, please contact journals.
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This research topic is little explored in the academic world, thus, this thesis contributes to the advancement of statistical Metadata Mostrar registro completo. Sign In or Create an Account. The proportion of these that died from the hydric stress of condition 2 was detected under condition 3.
How to cite this article. At the beginning of fas month, from June to September, the soil under three cages was collected to a depth of 2 cm. At the beginning of September, when the eggs naturally enter dae postdiapause or quiescence without any token stimuli Pires et al.
However, the occurrence of sparse and less frequent rainfall d of dampened soil followed by more than 16 d of droughtfollowing the second half of August, drastically increases mortality and reduces the chances of economically important population densities developing see also Pires et al. Inimigos naturais encontrados na regiao de Campo Grande, MS Teste de insecticidas para controle da cigarrinha-das-pastagens Deois incompleta Walk Evidencias de acao inibidora da jurema-preta na fermentacao in vitro de gramineas forrageiras Potencial de la leucaena Leucaena leucocephala Lam.
First instars usually feed gregariously in the same spittle, and all nymphs that died were removed with a small paintbrush. The movement of marked and recaptured populations was monitored with non-toxic fluorescent powder.
Groups of 20 eggs with fully developed embryos were chosen randomly and placed at the base of potted plants of B. Eggs in the final stage of embryonic development are also susceptible to desiccation. Newly emerged nymphs desiccate quickly and die if they do not find a cigwrrinha plant, or if a drought period with high temperature occurs at this nymphal stage Pires et al.
Insecta; Homoptera; Cercopidae; flight pattern; population dynamics; Deois flavopicta. It is possible that sudden weather variation after the beginning of the rainy season may play an important role in the survivorship of first-generation nymphs and thus the size of subsequent population peaks.
Modeled and observed curves of hatching proportion were compared using the Kolmogorov-Smirnov test Wilkinson Nymphs trapped inside eggs after 60 d were considered dead. Egg hatching was monitored every other day until the emergence or death of all eggs in each replicate.
Movements of migration and dispersion of adult spittlebugs. Mixed risk-spreading strategies and the population dynamics of a Brazilian pasture pest, Deois flavopicta.
Environmental factors affecting spittle-bug egg survival during the dry season in central Brazil. A number of studies have confirmed the low response of diapausing eggs to environmental factors during the dry season in June and July Sujii et al. View large Download slide. In this work the efficacy the fungus of applied at in twice formulations concentrated emulsifiable oil and wettable powdertrhee doses 1,0 x, 1,5 x, 2 x viable conidias ha-1 in once for twice during the pest infested with period.
The base of the cage was buried 10 cm deep to impede the entrance of soil insects from beneath. Our experiments and field observations indicate that in years when the rains start in late August or September and are frequent periods of interruption no longer than 4 dsurvival of postdiapause eggs and newly emerged nymphs is maximized, and the chances of population outbreaks are increased Fig.
Tags from this library: D h until the eggs reached the final stage of embryonic development, following the description of Koller et al.
Following this dry period, eggs were again transferred to moist conditions condition 3as described above for condition 1, until hatching of quiescent eggs or death of all individuals. With this procedure, it was possible to distinguish the proportion of eggs that resumed final embryonic development in response to different periods of exposure to moisture condition 1 from those that were naturally infertile.