Genomic analysis of NAC transcription factors in banana (Musa acuminata) and definition of NAC orthologous groups for monocots and dicots

Identifying the molecular mechanisms underlying tolerance to abiotic stresses is important in crop breeding. A comprehensive understanding of the gene families associated with drought tolerance is therefore highly relevant. NAC transcription factors form a large plant-specific gene family involved in the regulation of tissue development and responses to biotic and abiotic stresses. The main goal of this study was to set up a framework of orthologous groups determined by an expert sequence comparison of NAC genes from both monocots and dicots. In order to clarify the orthologous relationships among NAC genes of different species, we performed an in-depth comparative study of four divergent taxa, in dicots and monocots, whose genomes have already been completely sequenced: Arabidopsis thaliana, Vitis vinifera, Musa acuminata and Oryza sativa. Due to independent evolution, NAC copy number is highly variable in these plant genomes. Based on an expert NAC sequence comparison, we propose forty orthologous groups of NAC sequences that were probably derived from an ancestor gene present in the most recent common ancestor of dicots and monocots. These orthologous groups provide a curated resource for large-scale protein sequence annotation of NAC transcription factors. The established orthology relationships also provide a useful reference for NAC function studies in newly sequenced genomes such as M. acuminata and other plant species

Ultrasound-induced emulsification of subcritical carbon dioxide/water with and without surfactant as a strategy for enhanced mass transport

Pulsed ultrasound was used to disperse a biphasic mixture of CO2/H2O in a 1 dm3 high-pressure reactor at 30 °C/80 bar. A view cell positioned in-line with the sonic vessel allowed observation of a turbid emulsion which lasted approximately 30 min after ceasing sonication. Within the ultrasound reactor, simultaneous CO2-continuous and H2O-continuous environments were identified. The hydrolysis of benzoyl chloride was employed to show that at similar power intensities, comparable initial rates (1.6 ± 0.3 × 10–3 s–1 at 95 W cm–2) were obtained with those reported for a 87 cm3 reactor (1.8 ± 0.2 × 10–3 s–1 at 105 W cm–2), demonstrating the conservation of the physical effects of ultrasound in high-pressure systems (emulsification induced by the action of acoustic forces near an interface). A comparison of benzoyl chloride hydrolysis rates and benzaldehyde mass transport relative to the non-sonicated, ‘silent’ cases confirmed that the application of ultrasound achieved reaction rates which were over 200 times faster, by reducing the mass transport resistance between CO2 and H2O. The versatility of the system was further demonstrated by ultrasound-induced hydrolysis in the presence of the polysorbate surfactant, Tween, which formed a more uniform CO2/H2O emulsion that significantly increased benzoyl chloride hydrolysis rates. Finally, pulse rate was employed as a means of slowing down the rate of hydrolysis, further illustrating how ultrasound can be used as a valuable tool for controlling reactions in CO2/H2O solvent mixtures

Climatização de banana 'prata anã'.

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Local Unitary Classification of Arbitrary Dimensional Multipartite Pure States

We propose a practical entanglement classification scheme for general multipartite pure states in arbitrary dimensions under local unitary equivalence by exploiting the high order singular value decomposition technique and local symmetries of the states. By virtue of this scheme, the method of determining the local unitary equivalence of $n$-qubit states proposed by Kraus is extended to the case for arbitrary dimensional multipartite states.Comment: 10 pages; published in Phys. Rev. Let

Holistic Approach to Biodiversity and Bioindication in Soil

To study and investigate soil biodiversity is a difficult task because of the complex interactions that exist in soil and the need for considerable expertise to undertake the necessary investigations. The factors that influence biodiversity are diverse: some are natural, for example soil acidity, water retention, temperature and organic matter content, others are anthropogenic, for example human population pressure. This report summarises the results of the multidisciplinary BIO-BIO study of biodiversity and bioindication, conducted within the Pavia Project, which had as its principal objective the evaluation of the quality and health of soil in Pavia Province, Lombardy, in northern Italy. The area under investigation covered 3000 km2 and the project took into account of the different uses of soil. International standard methods were adopted for the identification of sampling points, the collection, treatment and analysis of the samples for heavy metals, macro-elements, dioxins, furans, soil acidity, physical properties (water retention, pore size, geochemical profile, etc.) and biological data (bacteria and terrestrial mosses). The differences in soil biodiversity that have resulted from different management practices, namely: organic or ¿biological¿ farming; conventional ¿manure¿ farming using animal excreta and mineral fertilizers; and sewage sludge ¿amended¿ applications to soil, have been studied on a seasonal basis (4 sampling per year) and analysis of soil samples taken at 0--5 cm; 0-15 cm and 15-30 cm depth. Some general ideas of what needs to be done in this field are outlined, whilst, at the same time, suggesting the basis for further studies. Bacteria, collembola and earthworms, which cover the three nutritional nets, are the most useful bio-indicators for appraising the evolution of biodiversity and assessing soil quality. To evaluate the biodiversity ¿in soil¿ means to appraise the quality of the soil. Only integrated studies, that take into consideration the chemical, physical and biological nature of soil, will lead to a full understanding of soil biodiversity.JRC.DDG.H.7-Land management and natural hazard

The pgip family in soybean and three other legume species: evidence for a birth-and-death model of evolution

Polygalacturonase-inhibiting proteins (PGIPs) are leucine-rich repeat (LRR) plant cell wall glycoproteins involved in plant immunity. They are typically encoded by gene families with a small number of gene copies whose evolutionary origin has been poorly investigated. Here we report the complete characterization of the full complement of the pgip family in soybean (Glycine max [L.] Merr.) and the characterization of the genomic region surrounding the pgip family in four legume species. Results: BAC clone and genome sequence analyses showed that the soybean genome contains two pgip loci. Each locus is composed of three clustered genes that are induced following infection with the fungal pathogen Sclerotinia sclerotiorum (Lib.) de Bary, and remnant sequences of pgip genes. The analyzed homeologous soybean genomic regions (about 126 Kb) that include the pgip loci are strongly conserved and this conservation extends also to the genomes of the legume species Phaseolus vulgaris L., Medicago truncatula Gaertn. and Cicer arietinum L., each containing a single pgip locus. Maximum likelihood-based gene trees suggest that the genes within the pgip clusters have independently undergone tandem duplication in each species. Conclusions: The paleopolyploid soybean genome contains two pgip loci comprised in large and highly conserved duplicated regions, which are also conserved in bean, M. truncatula and C. arietinum. The genomic features of these legume pgip families suggest that the forces driving the evolution of pgip genes follow the birth-and-death model, similar to that proposed for the evolution of resistance (R) genes of NBS-LRR-type

Considerações sobre o ponto de colheita de manga para exportação.

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