Comparative histopathology of virulent and avirulent Meloidogyne javanica populations on susceptible and resistant tomato plants.

The Mi-1.2 gene confers resistance to a wide range of Meloidogyne species, being the most important resistance factor employed in tomato breeding so far. However, many aspects related to the interaction of Mi-1.2-carrying tomato cultivars and virulent/avirulent Meloidogyne populations have not yet been clarified. Herein, comparative histopathological analyses were carried after inoculation of the homozygous (Mi-1.2/Mi-1.2) tomato rootstock 'Guardião' and the susceptible cultivar 'Santa Clara' (mi-1.2/mi-1.2) with virulent and avirulent populations of M. javanica. In the susceptible control, it was possible to visualize second stage juveniles (J2) of avirulent population and feeding sites from 2 to 30 days after infection (DAI) with females reaching maturity at 24-34 DAI. In the resistant rootstock, the Mi-1.2 gene-mediated resistance was related mainly to early defense responses (pre-infection and hypersensitive reaction), which led to an immunity-like phenotype that completely prevented the reproduction of the avirulent Meloidogyne population. On the other hand, J2s of the virulent M. javanica population were able to penetrate roots much more than the avirulent population, migrated and developed normally, showing intense and similar pattern of penetration from 4 to 34 DAI in the root tissues of both resistant and susceptible tomato genotypes. The total numbers of J2, J3, J4, and females counted in 'Santa Clara' for the virulent population of M. javanica were higher than in 'Guardião'.

Escala de avaliaçäo de traços autísticos (ATA): validade e confiabilidade de uma escala para a detecçäo de condutas autísticas / Evaluation scale of autistic behavior: validity and reliability of a scale for autistic behavior detection

O objetivo deste estudo foi, a partir da análise de uma populaçao de 31 pacientes portadores de deficiência mental e de 30 pacientes diagnosticados como portadores de autismo, conforme os critérios diagnósticos do DSM-IV, traduzir, adaptar e validar a escala de traços autísticos, construída em Barcelona por Ballabriga e colaboradores. O ponto de corte encontrado foi 15 (p=0,05); o coeficiente de variaçao (confiabilidade), 0,27; a validade externa mostrou baixa concordância (kappa=0,04) e a validade interna foi 100 por cento, mostrando que, em todos os pacientes avaliados, os diagnósticos clínicos concordaram com os realizados através da escala. O índice de correlaçao foi 0,42, mostrando-se específico para os quadros autísticos. Apresentou ainda, capacidade de discriminaçao e consistência interna, com alfa de Cronbach 0,71. Consideramos, assim, que a escala mostra-se confiável para a sua utilizaçao em nosso meio.