Banco de sementes e artropodofauna associada à soja resistente ao glifosato em função do manejo de plantas daninhas

Abstract

Weeds interfere in the development and soybean yield and infestation is directly related to the soil seed bank that reflects the agricultural practices adopted. They can also be host of insect pests and / or their natural enemies. So, knowledge of weeds and arthropod community associated with weed is information that can assist decision-making in management. Thus, this thesis aimed to: I - study the seed bank of weeds (BSS) under different soil management systems and cultures - conventional system (SCS) and no tillage (SDS) in soybeans / wheat and conventional system (SCR) and no tillage (SDR) rotation with winter and summer, in the years 2010/2011 and 2011/2012 and II - to verify the incidence of associated arthropod genetically modified soybean resistant to glyphosate, in coexistence with plants weeds in crop years 2010/2011 and 2011/2012. In all management systems predominate species of dicots, and the Asteraceae family with greater diversity. Of Monocotyledonous, dominates the family Poaceae. In the SDS and SDR systems the family Amaranthaceae is the most representative. In the SCS system, Portulacaceae is the most abundant family, while the SCR, Poaceae dominated in 2010/2011 and Portulacaceae in 2011/2012. In the SD system, the seed bank is higher in crop rotation and succession in the surface layer, and in the succession of cultures in the deepest layer. In crop rotation, in the deeper layers is larger in SC system. The relative importance of species is variable depending on the management systems used and the agricultural year. Portulaca oleracea L. is the specie of greater relative importance in the SCS and SCR systems and Amaranthus hybridus var. paniculatus (L.) Thell in the SDS and SDR systems. The similarity of species seed bank is high among systems and between the composition of the seed bank and aboveground field is high in 2010/2011 and lower in 2011/2012. The population of Anticarsia gemmatalis, Pseudoplusia includens and set defoliator caterpillars is higher in the absence of weeds in soybean breeding period. The weed management does not affect the population in the reproductive Piezodorus guildinii culture. However, there is a higher population in the absence of weeds in the crop year 2011/2012, from the R6 growth stage. Populations of Euchistus heros, Nezara viridula, Acrosternum hilare, Edessa meditabunda, Dichelops melacanthus and Diabrotica speciosa not suffer influence of weed management, considering the reproductive soybeans. The weed management does not affect the occurrence of spiders, Geocoris punctipes, Cycloneda sanguinea and Eriopis connexa.