The Theobroma lethal character Luteus-Pa segregates in a 3:1 ratio, expresses in recessive homozygosis, initially inducing leaf chlorosis and finally provoking seedlings death. The objective of this work was to evaluate gas exchange, chlorophyll fluorescence emission, chemical composition and oxidative stress of wild and mutant seedlings resulting from the crosses Pa 30 × Pa 169 and its reciprocal, aiming to elucidate the seedlings death induced by Luteus-Pa. At 15 day after emergence (DAE) differences began to appear between the wild type and mutant. Mutant seedlings showed: (1) lack of photosynthesis and alterations in chloroplast morphology; (2) lower level of three abundant groups of proteins in leaves; (3) decrease in the content of chloroplastidic pigments (4) decrease in peroxidases activities and increase in leaf polyphenol oxidase activity; (5) decrease in carbohydrate and concentration of some nutrients and low dry mass in all plant parts. In leaves of mutant seedlings of both crosses damages occurred in the system responsible for the photochemical phase of photosynthesis. Variations in growth parameters and subsequent seedling death up to 60 DAE were related to exhaustion of cotyledonary reserves, inactive photosynthetic apparatus and oxidative stress.

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rEsumo-o alagamento do solo pode promover alterações no metabolismo celular e causar desvios nas condições ótimas de crescimento das plantas, gerando uma condição de estresse. objetivou-se no presente trabalho avaliar os efeitos do alagamento no crescimento e na nutrição mineral de seis clones de T. cacao (CP-49, CCn-10, CP-06, CEPEC-2007, CEPEC-2008 e PS-1319, para elucidar possíveis mecanismos de tolerância ao alagamento. mudas clonais de T. cacao, com 6 meses de idade, foram submetidas ao alagamento, juntamente com o tratamento-controle (não alagado), por 30 dias. Observou-se, no final desse período, que o alagamento promoveu diminuição nas taxas de crescimento relativo radicular (exceto para CP-06) e de área foliar, acúmulo de matéria seca e incremento nas taxas de crescimento relativo caulinar (exceto para os

ABSTRACT. The lethal gene 'Luteus-Pa' is found in cacao genotypes (Theobroma cacao) of the Parinari (Pa) series, from Peru. Seedlings affected by this gene have yellowing leaves and subsequently die. We mapped this gene based on microsatellite markers and RAPDs, in order to elucidate the inheritance of 'Luteus-Pa' and investigate possible lethal mechanisms. DNA samples of genitors were amplified with 87 SSR and 64 RAPD primers. The SSR primers amplified 65 RAPD primers, giving 179 polymorphic bands. After screening with SSR and RAPD markers, we selected 20 SSR primers, two SSR primers with ESTs and 22 RAPD primers that were polymorphic for genitors Pa 30 and Pa 169. Only two of the 22 RAPD primers and three of the 20 SSR primers were informative and polymorphic in the analysis of the bulk samples of progenies. Among these, primer RAPD E11 produced a band linked to the lethal gene (38.5 cM); none of the SSRs were associated with 'Luteus-Pa'.

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ABSTRACT. The recessive lethal character Luteus-Pa is found in cacao (Theobroma cacao) genotypes of the Parinari series (Pa) and is characterized by expression of leaf chlorosis and seedling death. Several genotypes of the Pa series are bearers of the gene responsible for the expression of the Luteus-Pa character, which can be used as a tool for determining relationships between genotypes of this group. To evaluate this phenomenon, we analyzed the differential expression of genes between mutant seedlings and wild-type hybrid Pa 30 x 169 seedlings, with the aim of elucidating the possible lethal mechanisms of the homozygous recessive character Luteus-Pa. Plant material was harvested from leaves of wild and mutant seedlings at different periods to construct a subtractive library and perform quantitative analysis using real-time PCR. The 649 sequences obtained from the subtractive library had an average length of 500 bp, forming 409 contigs. The probable proteins encoded were grouped into 10 functional categories. Data from ESTs identified genes associated with Rubisco, peroxidases, and other proteins and enzymes related to carbon assimilation, respiration, and photosystem 2. Mutant seedlings were characterized by synthesizing defective PsbO and PsbA proteins, which were overexpressed from 15 to 20 days after seedling emergence.

O biodiesel é um biocombustível renovável que pode ser obtido através do processo de transesterificação. Assim como as demais atividades industriais o processo de produção de biodiesel apresenta riscos e perigos à saúde ambiental, pois em sua produção envolve substâncias tóxicas, como o hidróxido de sódio e/ou de potássio que podem provocar intoxicação, e substâncias alcoólicas inflamáveis como o metanol, que quando submetidas a altas temperaturas, caso ocorra algum evento indesejado e inesperado, pode causar danos materiais e financeiro, além de queimaduras nos funcionários, visto o grande risco de explosão. Nesse contexto, este trabalho tem por objetivo realizar a simulação do processo de transesterificação do biodiesel através do software DWSIM, analisar os seus componentes e montar um Programa de Gerenciamento de Risco (PGR) contendo um inventário de risco e plano de ação, visando a prevenção e minimização dos riscos do processo de produção do biodiesel via transesterificação

Native and exotic species of economically used plants in the Southern Bahia Atlantic Forest region Espécies nativas e exóticas de plantas economicamente usadas na região de Mata Atlântica do Sul da Bahia