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This study recorded the choice of dry plant of Conyza spp as oviposition site by cicada Quesada gigas (Olivier, 1790). We presented issues of natural history of the cicadas that indicate the inability of immatures to complete life cycle in this species of plant. Some implications on cultures where Q. gigas has economic importance are also discussed. [ABSTRACT FROM AUTHOR]

Estudou-se a biologia de Spodoptera cosmioides (Walk.) sobre quatro hospedeiros naturais (folhas de cebola, mamona, soja cv. Embrapa 48 e feijão cv. Carioca). Foram avaliados a duração e viabilidade das fases imaturas e do ciclo total, número de ínstares, peso de pupas, razão sexual, porcentagem de deformação de adultos e de adultos não liberados dos invólucros pupais, longevidade de adultos, fecundidade e viabilidade de ovos. Observou-se menor duração e maior viabilidade do período ovo-adulto para mamona e cebola (39,7 dias e 21,7% e 40,5 dias e 21,8%, respectivamente), do que para soja (46,0 dias e 3,9%). O peso pupal foi de 444,6 mg em cebola, 420,0 em feijão, 396,6 em mamona e 298,7 em soja. Constatou-se um predomínio de seis ínstares larvais em folhas de cebola e mamona, ocorrendo também sete para alguns indivíduos, enquanto que em soja predominou a ocorrência de sete, também verificando oito ínstares, indicando uma menor adequação nutricional deste hospedeiro. As fêmeas apresentaram duração da fase pupal significativamente menor do que os machos em todos hospedeiros, fazendo com que a emergência do adulto ocorresse antes dos machos. Em cebola, a longevidade de adultos foi significativamente superior aos demais hospedeiros. A fecundidade foi maior em cebola e mamona (3224 e 3206 ovos/fêmea, respectivamente), enquanto que para soja observou-se 1353 ovos/fêmea. Em folhas de feijão, o desenvolvimento do inseto foi prejudicado por caracteres morfológicos - pilosidade, que promoveram elevada mortalidade na fase larval.The biology of Spodoptera cosmioides (Walk.) was studied on four natural hosts (onion leaves, castor oil plant, soy cv. Embrapa 48 and bean cv. Carioca). The duration and viability of immature phases and total cycle, instar number, pupals weight, sexual ratio, percentage of deformed adults and adults not released of pupal beg, adults' longevity, fecundity and eggs viability were evaluated. It was observed in castor oil plant and onion shorter duration and larger viability of total cycle (39.7 days and 21.7%; 40.5 days and 21.8%, respectively), in contrast of soy (46.0 days and 3.9%). The pupal weight was 444.6 mg on onion, 420.0mg on bean, 396.6mg on castor oil plant and 298.7 mg on soy. Onion and castor oil plant leaves had a predominance of six larval instars, also happening seven for some of them, while in soy the occurrence of seven prevailed, also happening eight instars, indicating less nutritional adaptation of this host. The females had pupal phase significantly smaller than the males in all the hosts, making adults emergency happen before the males. In onion, the longevity of the adults was significantly superior comparing with the other hosts. The fecundity was better on onion and castor oil plant (3224 and 3206 eggs/female, respectively), therefore on soy was observed 1353 eggs/female. In bean leaves, the development of the insect was harmed by morphologic characters, which promoted high mortality in the larval phase.

Beetles belonging to the superfamily Scarabaeoidea occupy different habitats, present feeding habits diversified, play an important ecological role and several species have agricultural importance. However, studies with this group in the Brazilian Cerrado are scarce. In this review we carried out a survey of scientific articles published in the past 30 years concerning Scarabaeoidea in the Cerrado. Were found 64 studies in nine Brazilian states. The studies focused on four main topics: pest species, bioecology, biodiversity and ecological importance, techniques and methodologies for collecting Scarabaeoidea. The results of this review indicate that few studies have been conducted with Scarabaeoidea in the Cerrado in recent decades compared to the importance and diversity of this group of insects. [ABSTRACT FROM AUTHOR]

ABSTRACT: This study recorded the choice of dry plant of Conyza spp as oviposition site by cicada Quesada gigas (Olivier, 1790). We presented issues of natural history of the cicadas that indicate the inability of immatures to complete life cycle in this species of plant. Some implications on cultures where Q. gigas has economic importance are also discussed.