Carlos Roberto Sousa e Silva

Greenidea ficicola Takahashi (Hemiptera: Greenideidae), a new aphid in Brazil

Greenidea ficicola Takahashi (Hemiptera: Greenideidae) is recorded in the Neotropical Region. G. ficicola was collected in the municipality of Sao Carlos, Sao Paulo State, Southeastern Brazil. The specimens are apterous forms collected on Ficus microcarpa L. (Moraceae) leaves in September 2003 and September 2004.

Impacto da adubação orgânica sobre a incidência de tripes em cebola

The impact of organic fertilization on the incidence of thrips (Thrips tabaci Lind.) on onion was evaluated at Ituporanga Experimental Station in Santa Catarina State, Brazil, from August to December, 1998. The treatments using organic fertilization were based on the N needs determined by previous soil analysis. Using different organic sources were 75.0 Kg/ha of N (swine manure; Barriga Verde® poultry manure; compost; turkey manure; humus); 37.5 Kg/ha of N (swine manure half regular rate); two chemically fertilized controls with 30-120-60 Kg/ha of N-P2O5-K2O and double rate (60-240-120 Kg/ha of N-P2O5-K2O); and finally the unfertilized control. The incidence of thrips was similar between treatments with fertilized and no fertilized check. Treatments with mineral fertilization presented the same incidence of thrips when compared to organic fertilization. During severe infestation period, the correlation between the use of mineral nutrients and the T. tabaci incidence was positive and was described by a model involving the levels of K/Zn, B and N. The correlation of nutrient in the leaves and the infestation of thrips on onion was not linear. The organic fertilization can substitute the mineral one on onion crops, without reducing yield.

Efeito de espécies vegetais em bordadura em cebola sobre a densidade populacional de tripes e sirfídeos predadores

Analisou-se a relacao entre o efeito do plantio de diferentes especies vegetais, em bordadura, na cultura da cebola, Allium cepa L, na incidencia de Thrips tabaci Lind. e sirfideos predadores, Toxomerus spp. O experimento foi conduzido na Epagri, EE de Ituporanga, de agosto a dezembro de 1998. Os tratamentos foram cebola em monocultivo; cebola + trigo mourisco (Fagopyrum esculentum Moench); cebola + nabo forrageiro (Raphanus sativus L. var. oleiferus Metzg.); cebola + cenoura (Daucus carota L., cv. Nantes e cv. Brasilia); cebola + milho (Zea mays L.); cebola + rucula (Eruca sativa L.) + vegetacao espontânea. O plantio de diferentes especies vegetais em bordadura nao provocou diferencas significativas na incidencia de tripes e sirfideos predadores. A produtividade comercial de bulbos de cebola foi similar em sistema de monocultivo e diversificado, sugerindo ser possivel adotar tais sistemas sem perdas em rendimento.

Incidência do míldio em cebola sob adubação mineral e orgânica

The incidence of downy mildew, Peronospora destructor Berk. Casp., in onion growing in chemical and organic fertilized plots was evaluated in Ituporanga, Santa Catarina State, Brazil. Two experiments were carried out between August to December 1998. The treatments in the first experiment with organic sources were: 75.0 kg/ha of N (swine manure; poultry manure; compost; turkey manure; humus); 37.5 kg/ha of N (swine manure half dose); control (NPK, 30-120-60 kg/ha of N-P2O5-K2O) and double rate of NPK (60-240-120 kg/ha of N-P2O5-K2O); and unfertilized control. In mineral fertilization experiment, the mineral levels were 1 and 3 times the recommended rates based on soil analysis: 30-120-60 kg/ha of N-P2O5-k2O; 90-360-180 kg/ha of N-P2O5-K2O; 75.0 kg/ha of N; 225.0 kg/ha of N; 80.0 kg/ha of P2O5; 240.0 kg/ha of P2O5; 60.0 kg/ha of K20; 180.0 kg/ha of K20. Control plots with organic fertilization received swine manure + phosphate rock in three treatments (75.0 kg/ha of N + 80.0 kg/ha of P2O5; 225.0 kg/ha of N + 240.0 kg/ha of P2O5; 37.5 kg/ha of N + 40.0 kg/ha of P2O5) and unfertilized check. Downy mildew incidence was similar between treatments with fertilizer and no fertilizer check. Mineral fertilization did not increase downy mildew incidence compared to the organic treatments. The relationship between nutrient and disease varied according to sampling date and differed for mineral and organic sources.