RESUMOObjetivou-se, com este trabalho, avaliar os componentes agronômicos e o índice de colheita de genótipos de amendoim ereto e rasteiro submetidos a 27 dias de suspensão hídrica, no inicio da fase vegetativa. O experimento foi conduzido em casa de vegetação sob o delineamento inteiramente casualizado com esquema fatorial 8 x 2 (genótipos x tratamentos hídricos) com cinco repetições. As variáveis analisadas foram: peso seco da planta total, peso seco das raízes, altura da haste principal, produção de vagens planta -1 , índice de colheita e índice de tolerância à seca. Verificou-se que os genótipos eretos apresentaram melhor ajuste fisiológico quando submetidos ao estresse hídrico prolongado destacando-se genotipo 55 437 como mais tolerante. Todos os genótipos rasteiros foram sensíveis ao estresse hídrico, porém LViPE-06 foi menos sensível, sendo o mais promissor para geração de populações divergentes. Palavras-chave:Arachis hypogaea, tolerância à seca, semiárido, cultivar Agronomic characteristics and harvest index of different peanut genotypes submitted to water stress ABSTRACT Upright and runner peanut genotypes were subjected to 27 days of water suspension, starting at vegetative phase and evaluated for their agronomical components and harvest index. The trail was carried out in a greenhouse using a completely randomized design, with factorial scheme 8 x 2 (genotypes x treatment), with five repetitions. The following variables were analysed: dry weight of the plant, dry weight of roots, main stem height, pods plant -1 , harvest index and index of tolerance to drought. It was found that upright genotypes had better physiological adjustment when submitted to prolonged water stress, among them genotype 55 437 was more tolerant. All runner genotypes were sensitive to water stress, however LViPE-06 was less sensitive revealing as a promising material for the generation of divergent population.

Lactic acid bacteria isolated of nursing mothers have probiotic properties.

Approximately 75% of the worldwide production of hard natural fibers originates from sisal, an industrial crop from arid and semiarid tropical regions. Brazil is the world's largest producer of sisal fiber, accounting for more than 40% of the worldwide production, and sisal bole rot disease has been the main phytosanitary problem of this crop. All previous studies reporting Aspergillus niger as the causal agent of the disease were based on the morphological features of fungal isolates from infected plant tissues in pure cultures. Black aspergilli are one of the most complex and difficult groups to classify and identify. Therefore, we performed an integrative analysis of this disease based on the isolation of black aspergilli from the endospheres and soils in the root zones of symptomatic adult plants, in vivo pathogenicity tests, histopathology of symptomatic plants, and molecular phylogeny and worldwide genetic variability of the causal agent. All sisal isolates were pathogenic and unequivocally produced symptoms of bole rot disease in healthy plants. In all tree-based phylogenetic methods used, a monophyletic group formed by A. welwitschiae along with all sisal isolates was retrieved. Ten A. welwitschiae haplotypes have been identified in the world, and three occur in the largest sisal-producing area. Most of the isolates are from a unique haplotype, present in only the sisal-producing region. A. welwitschiae destroyed parenchymatic and vascular cylinder cells and induced the necrosis of internal stem tissues. Therefore, sisal bole disease is probably the consequence of a saprotrophic fungus that opportunistically invades sisal plants and behaves as a typical necrotrophic pathogen.

No abstract

The forest species are frequent targets of diseases. In this context, the plant-parasitic algae comprise a separate group in this process, including the algae genus Cephaleuros, which attacks mahogany cultivars. The objective of this work was to accomplish the molecular and morphological characterization of the causal agent of algae spots occurring in Brazilian mahogany (Swietenia macrophylla). Somatic and reproductive algae structures contained in lesions on the leaves had the DNA extracted and amplified by primers 18SHf and 18SLr of the rRNA nuclear gene 18S. Then, the amplicons were purified and sequenced. The algae structures too were characterized under light microscope. In addition, a total of 12 injured leaves located in the lower third of each attacked tree were randomly extracted for lesion characterization according to its size and number. After algae structures measurements, sporangiophores and sporangia had 260.2 x 12.9 μm and 25 x 18.8 μm. These measurements, combined with the molecular identification, indicated that the algae found in Brazilian mahogany leaves is C. virescens. Attacked leaves showed an average of 33 lesions, 60% of which were smaller than 2 mm in diameter, which shows great capacity of the pathogen to reach different parts of the foliar limb. These measurements, combined with molecular identification, confirmed the algae found in Brazilian mahogany leaves to be C. virescens.

The cocoa and palm oil agro-industries active in the state of Bahia, Brazil, generate high quantities of lignocellulosic wastes that could be recycled through their use in the formulation of substrates to cultivate edible mushrooms. Pleurotus ostreatus, also known as oyster mushroom, is the second most cultivated mushroom in the world due to its highly appreciated gastronomic, nutritional, and medicinal characteristics. This work evaluated the vertical mycelium growth, biological efficiency, mushroom yield, and nutritional composition of P. ostreatus produced in substrates formulated with a combination of palm oil fruit mesocarp (POFM) and cocoa almond peels (CAP) processing wastes. The substrates were formulated with the following POFM/CAP proportions (%/%): S1 – 86.4/9.6; S2 – 76.8/19.2; S3 – 67.2/28.8; S4 – 57.6/38.4, and S5 – 48.0/48.0. Substrates also received 3% powdered charcoal and 1% calcium carbonate. Substrates S1, S2, S3, and S4 were superior for vertical mycelium growth. S2 promoted the best biological efficiency (148.8%) and yield (560.5g·kg-1).The mushrooms produced in all substrates presented good nutritional values, although mushrooms produced using the S2 presented the highest crude protein content. Overall, S1 is the recommended substrate as it results in higher yields of nutrient rich mushrooms. Production of P. ostreatus in substrates composed of POFM and CAP represents a good alternative for recycling these wastes with potential economic and ecological benefits to regions where palm oil and cocoa are grown.

The objective of this work was to accomplish the micromorphological characterization of the causal agent of the algal spot in ‘Amrapali’ mango trees. Therefore, ‘Amrapali’ mango leaves exhibiting symptoms of algal spots were used for making microscope slides, on which the pathogen somatic and reproductive structures were measured. The dimensions obtained for sporangiophores and sporangia were 245.5-545.6 × 10.5-19.1 μm and 21.4-34.2 × 16.3-24.7 μm, respectively. Descriptions based on symptoms and micromorphology indicated that the algae are Cephaleuros virescens, since this morphological data corroborates with literature descriptions. Besides, the algae had already identified by DNA sequencing as C. virescens.

No abstract