This research will have the following objectives: to study the effects of the diuron + hexazinone and clomazone + ametryne herbicides on microbial activity in soil submitted to the systems of mechanical crop and manual crop of sugarcane (crop accomplished after burns of the sugar cane plantation) and to study the persistence of these products in the crop systems mentioned. The herbicides diuron + hexazinone (1170 + 330 g i.a ha-1) and clomazone + ametrina (1500 + 1000 g ha-1) will be applied in field in two areas cultivated by sugarcane (manual crop and mechanical crop for for the least 4 years) in the Center of Agrarian Sciences / UFSCar. After the application of the products, samples of the soil will be collected and put in erlenmeyer of 250 mL. In intervals of 5 days after the application, up to 40 days, collections of samples of the soil will be accomplished for the analyses microbiologic. The effects of the herbicides on the microbiota of the soil will be appraised through the parameters carbon of the microbial biomass (Cmic) and aerobic respirometry (mgC-C02). The microbiota of the soil acted by bacteria, fungi and actinomycetes will be evaluated by the counting technique in plates of Petri. In the persistence studies the treatments will constitute of applications in the field of diuron + hexazinone (1170 + 330 g i.a ha-1), clomazone + ametrina (1500 + 1000 g ha-1) and test without herbicide. The methodology used in the determination of the persistence will be the one of bioensaios, being used C. sativus as diuron + hexazine plant-test and P. glaucum as plant tests for clomazone + ametrina The bioindicadores will grow inside of a fitotron with the constant climatic conditions, using the soil amostrado 10 times in the experimental area up to 120 days after the treatments (DAT).
News published in Agência FAPESP Newsletter about the scholarship: