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The higher abundance of E. heros in neotropical soybean fields seems to result from higher competitive ability than its heterospecific competitor P. guildinii, which may prevent the higher losses caused by P. guildinii. © 2016 Society of Chemical Industry.

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Cannibalism in the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (FAW), is a limiting factor in a baculovirus production system. To detect the impact of cannibalism, a two-step bioassay was conducted with different larval ages of FAW fed on two food sources (corn and castor bean leaves) contaminated with the S. frugiperda multiple-embedded nucleopolyhedrovirus. In a first bioassay, the food source affected the cannibalism, being higher for all larval ages tested (5-, 6- and 7-day-old larvae) in larvae fed on corn than on those fed on castor bean leaves. Larval mortality, weight equivalent and larval equivalents (LEs) per hectare decreased as the larval age increased. Larval weight, occlusion bodies (OBs)/larva and total OBs increased when the larval age increased. In a second bioassay, in which only 6- and 7-day-old larvae were used because of the performance in the first bioassay, the cannibalism rates were affected by the interaction between food sources and time of feeding (48 and 72 h), reaching the highest values for 6- and 7-day-old larvae fed on corn leaves for 72 h. Mortality of the FAW was affected by the interaction between food sources, larval age and time of feeding. The lowest mortalities were on 7-day-old larvae when they were fed on castor bean leaves for 48 and 72 h. Larval weight, OBs/larva, total OBs and LEs were affected by the interaction between food sources and larval age. A significant correlation was observed between larval weight and OBs/larva that fed on both food sources, suggesting that larval weight can be used to achieve a concentration to be sprayed in 1 ha.

Here we report the characterization of a Spodoptera frugiperda multiple nucleopolyhedrovirus isolate, named SfMNPV-6nd, that does not cause the liquefaction of the host integument. The sequencing of the chitinase A (v-chiA) gene from SfMNPV-6nd revealed that it had a frameshift mutation that greatly reduced size of the putative enzyme. In order to evaluate the suitability of SfMPNV-6nd as a biopesticide, this isolate was compared with the highly virulent SfMNPV-19. Our results showed that the LC(50) of the two isolates were not significantly different, but that SfMNPV-6nd took a longer period of time to kill second instar S. frugiperda than SfMNPV-19.

Development and Reproduction of the Predator Podisus distinctus (Stal) (Heteroptera: Pentatomidae)Exposed to Sublethal Doses of Permethrin ABSTRACT -Development and reproduction were studied in the predator Podisus distinctus (Stal) subjected to sublethal doses of the insecticide permethrin under laboratory conditions. Third instar nymphs were subjected to topical application of permethrin at the doses of 0, 0.0172, 0.172, 1.72, 17.2 e 172 ppb. The only parameter statisticaly different was egg viability. This parameter had the gratest increase at the dose 0.172 ppb provinding evidence for the phenomenon of hormesis.

The large-scale production of Baculovirus to control fall armyworm, Spodoptera frugiperda, presents many limitations. The most important limiting factor is that the baculovirus, which infects fall armyworm, causes liquefaction of the integument immediately after death. This disruption of the integument difficultates the large scale production because dead insect must be frozen before being harvested. This fact implies in high lab work need, increasing the cost of the biopesticide. This problem was overcome by the discovery of a new baculovirus nucleopolyhedrovirus (NPV) isolate in Cascavel/PR, that doesn't cause liquefaction of the integument (isolate 6NR) immediately after the insect death. This is an extremely important factor in a large-scale baculovirus production. In addition, mortality caused by isolate 6NR on 6-day-old-larvae was above 93% (SEM=0.7%), the average weight dead larva was 116.21 mg (SEM=22.9), the larval equivalent and weight equivalent/ha were 15.04 g (SEM=1.2) and 140.32 larvae (SEM=20.1), respectively.