BackgroundFinding the best extraction method of proteins from lysed cells is the key step for detection and identification in all proteomics applications. These are important to complement the knowledge about the mechanisms of interaction between plants and phytopathogens causing major economic losses. To develop an optimized extraction protocol, strains of Acidovorax citrulli, Pectobacterium carotovorum subsp. carotovorum and Ralstonia solanacearum were used as representative cells in the study of phytopathogenic bacteria. This study aims to compare four different protein extraction methods, including: Trizol, Phenol, Centrifugation and Lysis in order to determine which are more suitable for proteomic studies using as parameters the quantity and quality of extracted proteins observed in two-dimensional gels.ResultsThe bacteria studied showed different results among the tested methods. The Lysis method was more efficient for P. carotovorum subsp. carotovorum and R. solanacearum phytobacteria, as well as simple and fast, while for A. citrulli, the Centrifugation method was the best. This evaluation is based on results obtained in polyacrylamide gels that presented a greater abundance of spots and clearer and more consistent strips as detected by two-dimensional gels.ConclusionsThese results attest to the adequacy of these proteins extraction methods for proteomic studies.

Xanthomonas campestris pv. viticola (Nayudu) Dye is the causal agent of bacterial canker of grapevine, which is the main grapevine bacteriosis in irrigated areas of the São Francisco river in the Pernambuco and Bahia states located in the Brazilian northeastern region. These states account for 99% of annual exports of the Brazilian table grape to Holland, Germany, England, France, Spain and the United States (Lazzarotto and Fioravanço 2013). Because there is no single most efficient method for the control of bacterial canker of grapevine, several preventive and eradication measures are recommended, making the disease control more difficult. This is mainly due to the ability of the bacterium to survive in infected plants, in symptomless plants as an epiphyte (Araujo 2001), in crop debris (Silva et al. 2012), in alternative hosts (Peixoto et al. 2007), in grapevine cutting tools and in water (Naue et al. 2014). Consequently, the disease continues to constrain the productivity of Valley vineyards, limit the sale of grapes in both national and international markets, and prevent the transfer of grapevine propagating material from the Brazilian states where the bacterium has been detected to other areas (Naue et al. 2014). Due to the economic damage caused by bacterial canker of grapevine, there has been a major effort to generate more information about X. campestris pv. viticola. Several bacterial species that affect different host plants and cause diverse disease phenotypes have the ability to adhere and form biofilms (Lorite et al. 2013; Zimaro et al. 2013;

RESUMO: O objetivo desse trabalho foi avaliar seis genótipos de milho com características promissoras para a produção de minimilho e adaptados à região da Zona da Mata de Pernambuco, região Nordeste do Brasil. O experimento foi conduzido no campus experimental da Fitotecnia na UFRPE, entre 2014/2015. Foram avaliados seis genótipos, quanto a dez variáveis agronômicas. Na análise de variância pode ser observado que as variáveis significativas para produção do minimilho foram: número de espigas, início para a diferenciação da panícula, altura da planta aos 30 dias após a emergência, peso da espiga e peso da parte aérea. As correlações genotípicas foram mais elevadas do que as fenotípicas, porém de mesmo sinal, indicando menor influência do ambiente na expressão dos caracteres. Na análise de trilha ficou demonstrado que mais de 96% (R 2 ) de influência das variáveis sobre número de espigas e com um baixo efeito residual 0,17, confirmando que as variáveis analisadas influenciam na produção do número de espigas do minimilho. Os caracteres mais importantes na determinação direta da produção do minimilho foram: altura de planta aos 30 e 60 dias após a emergência, peso de espigas e peso da parte aérea. Recomenda-se a utilização dos genótipos CMS47, CMS39 e AL-25 para futuros trabalhos de melhoramento.ABSTRACT: Six corn genotypes with promising characteristics for the production of mini-corn and adapted to the Zona da Mata region, Pernambuco, Brazil, were evaluated. The experiment was performed at the Phytotechnical Experimental Campus of the UFRPE, between 2014 and 2015. Six genotypes were evaluated for ten agronomic variables. Variance analysis revealed that the significant variables for mini-corn production were: number of spikes, differentiation panicle start, height of plant after 30 days of emergence, weight of spike and weight of aerial segment. Genotype co-relationships were higher than the phenotype ones, albeit of the same sign. This fact showed a smaller influence of the environment on the characteristics. Trail analysis revealed more than 96% (R2) of the variables´ influence on the number of spikes and low residual effect 0.17, confirming that variables affected the production of the number of spikes of mini-corn. The most important characteristics in the direct determination of mini-corn production were plant height at 30 and 60 days after emergence, spike weight and weight of the aerial segment. The use of genotypes CMS47, CMS39 and AL-25 is recommended for further improvement research work.