Inoculation of Schizolobium parahyba with Mycorrhizal Fungi and Plant Growth-Promoting Rhizobacteria Increases Wood Yield under Field Conditions.

Schizolobium parahyba var. amazonicum (Huber ex Ducke) occurs naturally in the Brazilian Amazon. Currently, it is being planted extensively because of its fast growth and excellent use in forestry. Consequently, there is great interest in new strategies to increase wood production. The interaction between soil microorganisms and plants, specifically in the roots, provides essential nutrients for plant growth. These interactions can have growth-promoting effects. In this way, this study assessed the effect of the inoculation with arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) on growth of S. parahyba var. amazonicum under field conditions. We used two native species of arbuscular mycorrhizal fungi, Claroideoglomus etunicatum (Ce), and Acaulospora sp. (Ac); two native strains of Rhizobium sp. (Rh1 and Rh2); and a non-native strain of Burkholderia sp. Different combinations of microorganisms were supplemented with chemical fertilizers (doses D1 and D2) in two planting methods, seed sowing and seedling planting. In seed sowing, the results showed that treatments with Ce/Rh1/Fertilizer D2 and Ac/No PGPR/Fertilizer D2 increased wood yield. In seedling planting, two combinations (Ac/Rh2/Fertilizer D1 and Ac/Rh1/Fertilizer D1) were more effective in increasing seedling growth. In these experiments, inoculation with AMF and PGPR increased wood yield by about 20% compared to the application of fertilizer alone.

Inoculant of Arbuscular Mycorrhizal Fungi (Rhizophagus clarus) Increase Yield of Soybean and Cotton under Field Conditions.

Nutrient availability is an important factor in crop production, and regular addition of chemical fertilizers is the most common practice to improve yield in agrosystems for intensive crop production. The use of some groups of microorganisms that have specific activity providing nutrients to plants is a good alternative, and arbuscular mycorrhizal fungi (AMF) enhance plant nutrition by providing especially phosphorus, improving plant growth and increasing crop production. Unfortunately, the use of AMF as an inoculant on a large scale is not yet widely used, because of several limitations in obtaining a large amount of inoculum due to several factors, such as low growth, the few species of AMF domesticated under in vitro conditions, and high competition with native AMF. The objective of this work was to test the infectivity of a Rhizophagus clarus inoculum and its effectiveness as an alternative for nutrient supply in soybean (Glycine max L.) and cotton (Gossypium hirsutum L.) when compared with conventional chemical fertilization under field conditions. The experiments were carried out in a completely randomized block design with five treatments: Fertilizer, AMF, AMF with Fertilizer, AMF with 1/2 Fertilizer, and the Control with non-inoculated and non-fertilized plants. The parameters evaluated were AMF root colonization and effect of inoculation on plant growth, nutrient absorption and yield. The results showed that AMF inoculation increased around 20 % of root colonization in both soybean and cotton; nutrients analyses in vegetal tissues showed increase of P and nitrogen content in inoculated plants, these results reflect in a higher yield. Our results showed that, AMF inoculation increase the effectiveness of fertilizer application in soybean and reduce the fertilizer dosage in cotton.

A implementação do uso dos sistemas rotatórios em endodontia / The implementation of rotary systems in endodontics

A introdução da técnica de instrumentação rotatória com instrumentos de níquel-titânio (NiTi) diminuiu o número de erros operatórios e aumentou a qualidade dos tratamentos endodôntico. Contudo, poucos trabalhos, no Brasil e no mundo, mostram a difusão do uso de técnicas rotatórias entre os profissionais que realizam endodontia. O presente estudo tem como objetivo analisar o grau de implementação do preparo de canais radiculares com sistemas rotatórios de NiTi na endodontia no Brasil. Para a coleta de dados, foi desenvolvido um questionário on-line autoaplicável composto por 16 questões, enviado para 250 endereços eletrônicos. Das 108 respostas obtidas, os dados analisados nos permitiram observar que 71% eram especialistas em endodontia e 26% estavam cursando a pós-graduação; 88% utilizavam instrumentação mecanizada e, desses, 55% combinavam a rotação contínua com a alternada e, 41% faziam usoapenas da rotação contínua. O risco de fratura e custo operacionalforam os principais motivos abordados para a não implementação dos sistemas rotatórios de NiTi em endodontia.

The use of NiTi rotary instruments in Endodontics increased the quality of endodontic treatments and reduced the number of errors during root canal preparation. There are few papers in Brazil and around the world analyzing the diffusion of this new technology. The aim of this study involving Brazilian dentists was analyzed the accept of the new technologic in Endodontics. The increased purchasing of this new technology does not necessarily lead to correct use and incorporation into practice. A questionnaire survey comprising 16 questions was sent to 250 students and endodontics?s e-mails. The sampling frame was 108, comprising 71% specialists and 26% postgraduate students. Rotary instruments were used by 88%, 55% of them used rotary and alternatedrotation system and 41% only rotary instrumentation. Fracture and the high cost of the instruments were the main reasons for not using rotary NiTi in endodontics.