Résumé
Com o objetivo de avaliar o efeito da consorciação e manejo de Brachiaria decumbenscv. 'Basilisk' em cafeeiro (Coffea arabicacv. 'Catuaí Vermelho') infestado por Pratylenchus brachyurus(Pb), o presente experimento foi desenvolvido em condições de casa de vegetação. Os tratamentos utilizados, com cinco repetições, foram: 1. Café não inoculado no limpo; 2. Café não inoculado consorciado com B. decumbens; 3. Café inoculado com 5000 juvenis e adultos de Pb por vaso (10L), no limpo; 4. Café inoculado com Pb consorciado com B. decumbenspodadas semanalmente; 5. Café inoculado com Pb consorciado com B. decumbenscom aplicação do herbicida glifosato. Aos 3, 4, 7, 10 e 11 meses após transplante dos cafeeiros, houve um aumento significativo na altura das plantas de cafeeiro sem nematoide mantidas no limpo, comparadas com os tratamentos com cafeeiros em solo infestado com Pb consorciado com B. decumbenspodadas e café em solo infestado com Pb consorciado com B. decumbenscom aplicação de glifosato. Na avaliação final, realizada 278 dias após à inoculação das plantas, o peso da matéria seca da parte aérea nos tratamentos com Pb consorciado com braquiária e com aplicação de glifosato apresentaram menores valores, quando comparado com a testemunha sem nematoide e sem plantas consorciadas. Com relação ao peso da matéria fresca das raízes, todos os tratamentos foram significativamente mais baixos do que a testemunha sem nematoide e sem consorciação. A população final de P. brachyurusnas raízes foi maior quando o café foi consorciado com braquiária.
The objective of this study was to evaluate the effect of intercropping and management of Brachiaria decumbenscv. 'Basilisk' in coffee (Coffea arabicacv. 'Catuai vermelho') infested withPratylenchus brachyurus(Pb), under greenhouse conditions. The treatments with five replicates were: 1. Coffee without Pb; 2. Coffee without Pb and intercropped with B. decumbens; 3. Coffee inoculated with 5000 juveniles and adults Pb per pot (10L) kept in clean; 4. Coffee inoculated with Pb intercropped with B. decumbenspruned weekly; 5. Coffee inoculated with Pb intercropped with B. decumbenswith application of the herbicide glyphosate. At 3, 4, 7, 10 and 11 months after transplantation of coffee plants ,there was a significant increase in the height of coffee plants without nematode kept in clean, compared with treatments with coffee in infested soil with Pb intercropped with B. decumbenspruned and coffee in soil infested with Pb intercropped with B. decumbenswith application of glyphosate. In the final evaluation, 278 days after inoculation , the dry weight of shoots in treatments with Pb and brachiaria and application of glyphosate were significantly lower when compared with untreated plants without nematode and intercropping. The weight of fresh roots, was significantly lower in all treatments compared to the control untreated plot. and without intercropping. The final population of P. brachyurusin roots was greater when coffee was intercropped with B. decumbens.
Résumé
A new approach to dengue vector surveillance based on permanent egg-collection using a modified ovitrap and Bacillus thuringiensis israelensis(Bti) was evaluated in different urban landscapes in Recife, Northeast Brazil. From April 2004 to April 2005, 13 egg-collection cycles of four weeks were carried out. Geo-referenced ovitraps containing grass infusion, Bti and three paddles were placed at fixed sampling stations distributed over five selected sites. Continuous egg-collections yielded more than four million eggs laid into 464 sentinel-ovitraps over one year. The overall positive ovitrap index was 98.5 percent (over 5,616 trap observations). The egg density index ranged from 100 to 2,500 eggs per trap-cycle, indicating a wide spread and high density of Aedes aegypti (Diptera: Culicidae) breeding populations in all sites. Fluctuations in population density over time were observed, particularly a marked increase from January on, or later, according to site. Massive egg-collection carried out at one of the sites prevented such a population outbreak. At intra-site level, egg counts made it possible to identify spots where the vector population is consistently concentrated over the time, pinpointing areas that should be considered high priority for control activities. The results indicate that these could be promising strategies for detecting and preventing Ae. aegypti population outbreaks.