Biological aspects of Schistocerca pallens, Stiphra robusta and Tropidacris collaris grasshoppers species at Rio Grande do Norte State, Brazil.
Chagas M. C. M., Moreira M. A. B., Barreto M. F. P.
Author Affiliation: EMBRAPA/EMPARN, Rua Chile, 172, Ribeira 59.012-250, Natal, RN, Brazil.
Acta Horticulturae : 83-88
Abstract : Schistocerca pallens, Stiphra robusta and Tropidacris collaris are the most important grasshopper species of economic importance in Rio Grande do Norte state, Brazil. S. pallens has caused serious damage to subsistence, native and introduced crops and survives by feeding on cashew trees (Anacardium occidentale), Euphorbia sp. and Herissantia nemoralis. S. robusta damages cashew, carob (Prosopis sp.) and guava trees (Psidium guajava), while T. collaris damages mostly mango (Mangifera indica) and coconut trees (Cocos nucifera). The eggs are laid on the ground at variable depths according to the species. Hatching is related to soil moisture. Under adverse feeding and climate conditions the grasshoppers remain at the diapause (quiescence) stage for a variable length of time. Under inland conditions, S. pallens had only one generation per year and remained at diapause during the adult phase for more than 6 months. Outbreaks of S. pallens were associated with rainfall years followed by periods of drought.