In 2013, the presence of Helicoverpa armigera (Hübner) was reported in cotton, soybean, corn and weeds in diverse regions of Brazil. We studied the biology and the fertility life table of this pest when reared on cotton (293 cv. CNPA RF), soybean (cv. Brasmax Power), corn (cv. BRS 1010), wheat (cv. BR 18) and on an artificial diet. Caterpillars were reared using the vegetative and reproductive structures of the hosts, under laboratory conditions (temperature 25 ± 1°C; relative humidity (RH) 70 ± 10%; photoperiod =14 h). The experimental design was completely randomized, with five treatments (four host plants and artificial diet) and 17 replications. Significant effects were verified for the different types of hosts tested on the growth of the insect as well as on fecundity and laying rate. The results showed that cotton and soybean had higher viability at the stages of growth, higher rate of survival of adult females in the reproductive period than the other host crops, and similar values for insects reared on an artificial diet, which reveals that cotton and soybean can be appropriate for rearing H. armigera on a natural diet. Corn and wheat showed high larval and pupal mortality and low biotic potential.

The increased corn planting grown in the late season crop and the use of a notillage planting system benefits the development of

Biological Notes and Behavior of Liogenys suturalis Blanchard (Coleoptera: Melolonthidae) in Mato Grosso do Sul State, BrazilABSTRACT -Liogenys suturalis Blanchard is one of the main soil pests associated to corn, wheat and oat crops in the Southern Mato Grosso do Sul State. This work aimed to investigate the bioecological and behavioral aspects of this pest. The study was carried out in several municipalities of Mato Grosso do Sul State under fi eld and laboratory conditions from August 2004 to December 2006. In the laboratory, we studied the incubation period and egg viability, the number of instars, and pupal and adult sexrelated traits. The insect distribution was determined yearly, as well as the period of insect fl ying and some behavioral aspects during mating. Egg viability averaged 81.7%, with an incubation period of 22.8 ± 4.32 days. Liogenys suturalis took the whole year to complete its life cycle, developing through three different instars. The highest larval feeding activity and development occurred in February and June, and adult fl ight activities were between the second fortnight of September and December. Sex dimorphism was observed in both pupae and adults. Flights were concentrated from 7:00 to 8:00 PM. The average time for mating was 9.82 min. The observed adult sex ratio was 0.63.

RESUMO-O comportamento produtivo do milho na presença de diferentes níveis populacionais de insetos adultos do percevejo Dichelops melacanthus em diferentes estádios de desenvolvimento da planta foi determinado em casa de vegetação e no campo com o objetivo de estimar o seu nível de dano econômico (NDE). A massa seca da parte aérea e o rendimento de grãos foram significativamente reduzidos na presença do percevejo, independente dos estádios de desenvolvimento da planta (V1 a V3). Em campo, utilizando-se gaiolas e infestando as plantas no estádio V1 durante 10 dias consecutivos, não foram observadas diferenças no peso de 100 grãos em relação às densidades populacionais utilizadas. No entanto, houve redução significativa no rendimento de grãos com o aumento da densidade populacional do percevejo. Em função dos resultados obtidos, é possível estimar que o NDE para D. melacanthus na cultura do milho é de 0,8 percevejo/m 2 , densidade populacional na qual o controle da praga é justificado economicamente. Palavras-chave: Dichelops melacanthus, estádio de desenvolvimento da planta, rendimento de grãos, densidade populacional, injúria.

Spodoptera frugiperda (smith, 1797) (Lepidoptera: Noctuidae) is considered to be the main pest of maize crops in brazil. Entomopathogenic nematodes (EPN) may be used to control this pest and exhibit different, unique abilities to search for their hosts. the movement of EPN in relation to S. frugiperda was evaluated. to test for horizontal movement, a styrofoam enclosure filled with sand was divided into segments, nematodes were placed at the entrance to the enclosure and a larva was placed at the end of each division. the same approach was used to evaluate vertical movement; however, PVc pipes were used in this case. In general, the mortality was inversely proportional to the initial distance between host and nematodes. In the vertical displacement test, both nematodes were able to kill the larvae up to a distance of 25 cm. therefore, the infective juveniles of H. amazonensis and S. arenarium can search out, infect and kill larvae of S. frugiperda at distances of up to 60 cm and 25 cm of horizontal and vertical displacement, respectively.