Diapausing eggs of the neotropical pasture pest, Deois flavopicta (Stal) (Hemiptera: Cercopidae), were exposed to low overnight temperatures that simulated field conditions during the dry season (23/12, 23/15 and 23/18°C day/night), for different periods (0-60 days). After treatment, eggs were kept at 28°C and contact water (100% humidity) until hatching. A group of diapausing eggs were kept all the time under this last condition as a control treatment. Time for hatching (in degree-days) was reduced with decrease in low overnight temperature and increase of exposure time to these cold shocks, although there was no interaction between the factors. Regression of exposure time to cold shock influencing the expected mean hatching time produced independent equations for temperatures below 18°C and 15°C. We constructed a model that simulates the expected proportion of the population hatching after the beginning of rainy season based on regression equations to mean hatching time and associated standard deviation. The simulation generated for the model correlated significantly with nymphal population observed in the field. These results showed that overnight soil temperatures below 18°C, as occurs in Central and South-eastern Brazil between May and August, shorten the period of diapause, increase quiescent eggs in the soil, and may synchronize the population hatching.614605613Botelho, W., Reis, P.R., Cigarrinhas-das-pastagens Homoptera - Cercopidae em Brachiaria decumbens sob diferentes cargas animais (1980) Epamig. Projeto Bovinos, Cigarrinha-das-pastagens, pp. 101-111. , Relatório 1974/79. Epamig, Belo HorizonteCosenza, G.W., Naves, M.A., (1980) O Controle da Cigarrinha-das-pastagens, 4p. , Embrapa/CPAC, Brasília, Embrapa/CPAC, Comunicado Técnico, 6Fontes, E.M.G., Pires, C.S.S., Sujii, E.R., Mixed risk-spreading strategies and the population dynamics of a brazilian pasture pest, Deois flavopicta (1995) Jour. Econ. Entomol., 88 (5), pp. 1256-1262Garrido, W.E., De Azevedo, L.G., Jarreta-Junior, M., (1982) O Clima da Região Dos Cerrados em Relação À Agricultura, 37p. , Embrapa/CPAC, Planaltina, DF, Embrapa/CPAC, Circular Técnica 9Koller, W.W., (1991) Cigarrinhas-das-pastagens (Homoptera: Cercopidae): Porcentagem de Ovos Diapáusicos Ovipositados em Diferentes Datas do Período de Infestação e a sua Relação com Condições Climáticas que Precederam Cada Oviposição, 106p. , Tese de Doutorado, UFPRKuo, J., Fox, E., Macdonald, S., (1992) Sigmastat: Statistical Software for Working Scientists, , Jandel Scientific, San FranciscoMagalhães, B.P., Parra, J.R.P., De Silva, A.B., Técnica de criação e biologia de Deois incompleta em Brachiaria (1987) Pesq. Agrop. Bras., 22 (2), pp. 137-144Oomen, P.A., A population study of the spittlebugs, Aeneolamia occidentalis (Walk) and Prosapia simulans (Walk) (Homoptera: Cercopidae) in Mexican Pangola pastures (1975) Z. Ang. Entomol., 79, pp. 225-238Pires, C.S.S., Fontes, E.M.G., Lima, L.H.C., Gomes, D.F., Influência do fotoperíodo sobre o término da diapausa de Deois flavopicta (Homoptera: Cercopidae) (1991) Cong. Bras. de Entomologia, 1, 366p. , p. 203. 13. Resumos, SEB, RecifePires, C.S.S., Sujii, E.R., Fontes, E.M.G., Tauber, C.A., Tauber, M.J., Dry-season embryonic dormancy in Deois flavopicta (Homoptera: Cercopidae): roles of temperature and moisture in nature (2000) Env. Entomol., 29 (4), pp. 714-720Reis, P.R., Silveira Neto, S., Botelho, W., Gaieras, L.A.C., Flutuação populacional da cigarrinhadas-pastagens (Homoptera: Cercopidae) e condições climáticas que influenciam sua ocorrência (1980) Epamig. Projeto Bovinos, Cigarrinha-das-pastagens, 153p. , pp. 6065. Relatório 1974-1979. Epamig, Belo HorizonteSnedcor, G.W., Cochran, W.G., (1980) Statistical Methods. 7.ed., 507p. , Iowa State University, IowaSujii, E.R., Garcia, M.A., Fontes, E.M.G., Carvalho, V., Efeito da temperatura e umi dade sobre o término da diapausa de ovos e densidade populacional da cigarrinha-das-pastagens, Deois flavopicta (Stal) (Homoptera: Cercopidae) (1995) An. Soc. Entomol. Brasil., 24 (3), pp. 465-478Tauber, M.J., Tauber, C.A., Nyrop, J.P., Villani, M.G., Moisture, a vital but neglected factor in the seasonal ecology of insects: Hypothesis and tests of mechanisms (1998) Env. Entomol., 27, pp. 523-530Tauber, M.J., Tauber, C.A., Nyrop, J.P., Soil moisture and postdormancy emergence of Colorado Potato Beetles (Coleoptera: Chrysomelidae): descriptive model and field emergence patterns (1994) Env. Entomol., (23), pp. 1485-1496Tauber, M.J., Tauber, C.A., Masaki, S., (1986) Seasonal Adaptations of Insects, 411p. , Oxford University Press, New YorkValério, J.R., Obtenção de ovos de cigarrinhas (Homoptera: Cercopidae) em Ágar-água (1993) An. Soc. Entomol. Brasil., 22 (3), pp. 583-590Valério, J.R., Koller, W.W., (1992) Proposição Para O Manejo Integrado das Cigarrinhas-das-pastagens, 37p. , Embrapa/CNPGC, Campo GrandeValério, J.R., Nakano, O., Danos causados pelo adulto de cigarrinha-das-pastagens Zulia entreriana (Berg, 1879) (Homoptera: Cercopidae) em plantas de Brachiaria decumbens Stapf mantidas em diferentes níveis de umidade (1987) An. Soc. Entomol. Brasil., 16 (2), pp. 341-350Wilkinson, L., (1990) Systat: the System for Statistics: Statistics, 676p. , Evanson, Illinois, Systat Inc