Understanding and engineering beneficial plant–microbe interactions:Plant growth promotion in energy crops

Plant production systems globally must be optimized to produce stable high yields from limited land under changing and variable climates. Demands for food, animal feed, and feedstocks for bioenergy and biorefining applications, are increasing with population growth, urbanization and affluence. Low-input, sustainable, alternatives to petrochemical-derived fertilizers and pesticides are required to reduce input costs and maintain or increase yields, with potential biological solutions having an important role to play. In contrast to crops that have been bred for food, many bioenergy crops are largely undomesticated, and so there is an opportunity to harness beneficial plant–microbe relationships which may have been inadvertently lost through intensive crop breeding. Plant–microbe interactions span a wide range of relationships in which one or both of the organisms may have a beneficial, neutral or negative effect on the other partner. A relatively small number of beneficial plant–microbe interactions are well understood and already exploited; however, others remain understudied and represent an untapped reservoir for optimizing plant production. There may be near-term applications for bacterial strains as microbial biopesticides and biofertilizers to increase biomass yield from energy crops grown on land unsuitable for food production. Longer term aims involve the design of synthetic genetic circuits within and between the host and microbes to optimize plant production. A highly exciting prospect is that endosymbionts comprise a unique resource of reduced complexity microbial genomes with adaptive traits of great interest for a wide variety of applications

Serodiagnosis of Babesia equi in horses submitted to exercise stress Diagnóstico sorológico de infestação por Babesia equi em eqüinos submetidos ao estresse do exercício

A complement fixation test (CFT), performed in microtitre plates, based upon the use of crude antigenic preparation of Babesia equi was adapted for the detection of antibodies in serum of infected horses. The indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) were also used for the immunodiagnosis of B. equi. Serum samples from 15 apparently healthy horses, previously conditioned to a high-speed equine treadmill, were taken before and after exercise. All the samples analyzed were positive for B. equi infection. There were no significant differences (P<0.01) between these 3 tests, or the condition of rest or stress. The combined use of CFT and IFAT or ELISA should be recommended in order to enable veterinary services to more efficiently prevent introduction of infected horses into disease-free areas.<br>A reação de fixação do complemento (RFC), realizada em microplacas, utilizando-se antígeno bruto de Babesia equi, foi adaptada para a detecção de anticorpos em soros de eqüinos infectados. A reação de imunofluorescência indireta (RIFI) e o ensaio imunoenzimático (ELISA) também foram utilizados para o imunodiagnóstico de B. equi. Amostras de soro foram obtidas de 15 eqüinos aparentemente sadios, submetidos a treinamento físico em esteira rolante de alto desempenho, sendo as amostras colhidas antes e após os exercícios. Todas as amostras testadas foram positivas para B. equi. Não houve diferença significativa (P<0,01) entre estes 3 testes sorológicos, ou entre a condição de estresse e repouso. A combinação da RFC com a RIFI ou ELISA pode ser recomendada a fim de evitar a entrada de eqüinos portadores em áreas consideradas livres da doença