Base genética do hábito de crescimento e florescimento em tomateiro e sua importânciana agricultura

Hybrids or open pollinated tomato cultivars used for sauces and ketchups production usually has determinate growth habit, while most of the genotypes used in the production to salads (in natura consumption) has indeterminate growth habit. Additionally, growth habit can have influence on culture management, productivity and total soluble solids (TSS) in fruits. The growth habit is mainly controlled by the gene SELF-PRUNING (SP), which is a component of a small gene family which is also part of the gene SINGLE FLOWER TRUSS (SFT), currently considered one of the components so sought after 'florigin'. Understanding the biochemical function and physiological effect of such genes in interaction with the environment and other genes (epistasis), allows the manipulation of parameters such as precocity and TSS. It also provides subsidies to understand the genetic basis of semideterminate growth, which combines the advantages of determinate and indeterminate habit and can be used for plant breeders to development of new cultivars.

Possible early foraminiferans in post-Sturtian (716-635 Ma) cap carbonates

Foraminifera are an ecologically important group of modern heterotrophic amoeboid eukaryotes whose naked and testate ancestors are thought to have evolved similar to 1 Ga ago. However, the single-chambered agglutinated tests of these protists appear in the fossil record only after ca. 580 Ma, coinciding with the appearance of macroscopic and mineralized animals. Here we report the discovery of small, slender tubular microfossils in the Sturtian (ca. 716-635 Ma) cap carbonate of the Rasthof Formation in Namibia. The tubes are 200-1300 mu m long and 20-70 mu m wide, and preserve apertures and variably wide lumens, folds, constrictions, and ridges. Their sometimes flexible walls are composed of carbonaceous material and detrital minerals. This combination of morphological and compositional characters is also present in some species of modern single-chambered agglutinated tubular foraminiferans, and is not found in other agglutinated eukaryotes. The preservation of possible early Foraminifera in the carbonate rocks deposited in the immediate aftermath of Sturtian low-latitude glaciation indicates that various morphologically modern protists thrived in microbially dominated ecosystems, and contributed to the cycling of carbon in Neoproterozoic oceans much before the rise of complex animals.

The 1420 Ma Indiavai Mafic Intrusion (SW Amazonian Craton): Paleomagnetic results and implications for the Columbia supercontinent

The configuration and the timing of assembly and break-up of Columbia are still matter of debate. In order to improve our knowledge about the Mesoproterozoic evolution of Columbia, a paleomagnetic study was carried out on the 1420 Ma Indiavai mafic intrusive rocks that crosscut the polycyclic Proterozoic basement of the SW Amazonian Craton, in southwestern Mato Grosso State (Brazil). Alternating field and thermal demagnetization revealed south/southwest ChRM directions with downward inclinations for sixteen analyzed sites. These directions are probably carried by SD/PSD magnetite with high coercivities and high unblocking temperatures as indicated by additional rock magnetic tests, including thermomagnetic data, hysteresis data and the progressive acquisition of isothermal remanent magnetization. Different stable magnetization components isolated in host rocks from the basement 10 km NW away to the Indiavai intrusion, further support the primary origin of the ChRM. A mean of the site mean directions was calculated at Dm = 209.8 degrees, Im = 50.7 degrees (alpha(95) = 8.0 degrees, K = 22.1), which yielded a paleomagnetic pole located at 249.7 degrees E, 57.0 degrees S (A(95) = 8.6 degrees). The similarity of this pole with the recently published 1420 Ma pole from the Nova Guarita dykes in northern Mato Grosso State suggests a similar tectonic framework for these two sites located 600 km apart, implying the bulk rigidity of the Rondonian-San Ignacio crust at that time. Furthermore these data provide new insights on the tectonic significance of the 1100-1000 Ma Nova Brasilandia belt-a major EW feature that cuts across the basement rocks of this province, which can now be interpreted as intracratonic, in contrast to previous interpretation. From a global perspective, a new Mesoproterozoic paleogeography of Columbia has been proposed based on comparison of these 1420 Ma poles and a 1780 Ma pole from Amazonia with other paleomagnetic poles of similar age from Baltica and Laurentia, a reconstruction in agreement with geological correlations. (C) 2012 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Tectonic implications of the 1419 Ma Nova Guarita mafic intrusives paleomagnetic pole (Amazonian Craton) on the longevity of Nuna

The Nuna supercontinent was probably assembled in the Paleoproterozoic, but its paleogeography and the timing for its demise are stills matter of debate. A paleomagnetic and geochronological study carried out on the Mesoproterozoic Nova Guarita dyke swarm (northern Mato Grosso State, SW Amazonian Craton) provides additional constraints on the duration of this supercontinent. Paleomagnetic AF and thermal treatment revealed south/southwest (northeast) magnetic directions with downward (upward) inclinations for 19 analyzed sites. These directions are carried by PSD magnetite with high unblocking temperatures as indicated by additional magnetic tests, including thermomagnetic curves, hysteresis loops and the progressive acquisition of isothermal remanence in selected samples. A positive contact test with the host granite in one of the studied dykes further attests to the primary origin of the characteristic magnetic component. A mean site direction was calculated at D-m = 220.5 degrees, I-m = 45.9 degrees (alpha(95) = 6.5 degrees, K = 27.7), which yielded a paleomagnetic pole located at 245.9 degrees E, 47.9 degrees S (A(95) = 7.0 degrees). Ar-40/Ar-39 dating carried out on biotites from four analyzed dykes yielded well-defined plateau ages with a mean of 1418.5 +/- 3.5 Ma. The Nova Guarita pole precludes a long-lived Nuna configuration in which Laurentia, Baltica, North China, and Amazonia formed a long and continuous block as previously proposed for the Paleoproterozoic. It is nevertheless fully compatible with a SAMBA (Amazonia-Baltica) link at Mesoproterozoic times. (C) 2011 Elsevier B.V. All rights reserved.

Base genética do hábito de crescimento e florescimento em tomateiro e sua importância na agricultura

Variedades ou híbridos de tomateiro utilizados para produção de molhos e ketchups costumam ter hábito determinado, enquanto a maioria dos genótipos utilizados na produção para mesa (consumo in natura) possuem hábito indeterminado. Além de influenciar no manejo da cultura, o hábito de crescimento pode alterar parâmetros de produtividade, como o teor de sólidos solúveis totais (SST) nos frutos. O hábito de crescimento é controlado principalmente pelo gene SELF-PRUNING (SP), que é um dos componentes de uma pequena família gênica da qual faz parte também o gene SINGLE FLOWER TRUSS (SFT), atualmente considerado um dos componentes do tão buscado "florígeno". O entendimento da função bioquímica e o efeito fisiológico de tais genes em interação com o ambiente e outros genes (epistasia) possibilita a manipulação de parâmetros como precocidade e SST. Além disso, fornece subsídios para compreender a base genética do crescimento semideterminado, que combina vantagens do hábito determinado e indeterminado, podendo ser usado pelos melhoristas de plantas para o desenvolvimento de novas cultivares.

150 anos de aporte de metais antropogênicos emu ma reserva da Biosfera: o Estudo de caso do sistema costeiro Cananéia-Iguape, Sudeste do Brasil.

Devido às suas cracaterísticas físico‐químicas e geológicas, estuários e lagunas acham‐se entre os ambientes mais sensíveis para a contaminação de metais e, em vários casos, este aporte de metais está relacionado à atividade mineira nas áreas a montante do curso de água, não raro a muitos quilômetros de distância. O sistema Cananéia‐Iguape consiste em um complexo de canais estuarino‐lagunares, localizados na Reserva da Biosfera do Lagamar. Esses canais são bordejados por vegetação de mangue exuberante, e são um importante criadouro natural de espécies de organismos de interesse commercial, e base da economia da população local.