Morphology and biomechanics of the nests of the Common Blackbird Turdus merula

Capsule Common blackbirds select different materials, with varying biomechanical properties, to construct different parts of their nest. Aims This study tested the hypothesis that outer components of a nest have a more structural role and so are stronger than materials used to line the cup. Methods Blackbird nests were measured prior to being dismantled to isolate structural components which were tested for mechanical strength and rigidity. Results Outer nest wall materials were significantly thicker, stronger and more rigid than materials in the inner structural wall or the cup lining. In the vertical plane materials used in the structural wall did not differ. By contrast, lining materials from the bottom of the nest cup were significantly thicker, stronger and more rigid than materials from the top of the cup. Conclusion Blackbirds use different materials in nest construction roles suited to their properties and so may be able to recognise the structural properties of these materials. Materials on the outside of the nest may have a key structural role during construction

Períodos de dessecação de urochloa ruziziensis e seu reflexo na produtividade da soja RR

Two field trials were carried out to evaluate the effects of burn-down timing of Urochloa ruziziensis on transgenic soybean establishment and yield under the no-tillage system. One experiment was conducted in Colina, SP - Brazil, in 2007/2008 season, and the other in Jaboticabal, SP - Brazil, 2009/2010 season. In 2007/2008, the experiment was carried out in a 7-year-old grass pasture of U. ruziziensis, with four burn-down timings of vegetation cover being tested 30, 20, 10, and 0 days in advance to soybean sowing. In 2009/2010, the experiment was conducted in an old grass pasture of U. ruziziensis cropped with maize the summer before. After maize harvesting, a natural re-infestation of U. ruziziensis occurred, corresponding to more than 80% of the vegetation cover. In this experiment, treatments corresponded to six burn-down timings of vegetation cover 25, 20, 16, 7, and 0 days in advance to soybean sowing. In all experiments, 1.44 kg a.e. ha-1 of herbicide glyphosate was applied, and the soybean cultivar M-SOY 7908 RR was used. The experiments were arranged in a randomized block design, with four replicates. The evaluations were carried out by measuring crop stand 20 days after sowing and pre-harvest, plant height, first pod insertion height, number of pods per plant, grain yield, and estimated yield. Data were submitted to ANOVA and the Tukey test at 5% of probability. Burn-down of U. ruziziensis performed at the same day of crop sowing reduced plant height, number of pods per plant, and crop grain yield. Burn-down timing of U. ruziziensis using glyphosate was recommended to be between 10 and 20 days in advance to crop sowing. In conclusion, soybean yield was affected by burn-down timing of U. ruziziensis

IMPACTOS AMBIENTAIS ORIUNDOS DA IMPLANTAÇÃO DE LOTEAMENTOS: O CASO DO NOVA ITUIUTABA II E IV.

O objetivo deste trabalho é identificar os principais impactos ambientais decorrentes da implantação dos loteamentos Nova Ituiutaba II e IV. Para isso, foram adotados os seguintes procedimentos metodológicos: revisão bibliográfica, trabalhos de campo, elaboração de perfil topográfico. Assim, identificou-se que a forma de ocupação do relevo para a implantação desses loteamentos gerou vários impactos como processos erosivos, assoreamento e aterramento da cabeceira de uma voçoroca

Precocidade sexual, eficiência reprodutiva e desempenho produtivo de matrizes jovens Nelore e cruzadas

RESUMO Com o objetivo de avaliar matrizes da raça Nelore (NE) e cruzadas 1/2 Angus + 1/2 Nelore (AN), 1/2 Caracu + 1/2 Nelore (CN) e 1/2 Senepol + 1/2 Caracu (SC) quanto à precocidade sexual em sistemas de recria a pasto, eficiência reprodutiva e desempenho produtivo das matrizes em cada grupo genético (GG), matrizes desses grupos foram produzidas por três safras. Foram avaliadas 40 matrizes AN, 37 CN, 51 NE e 43 SC. Para prenhez precoce, matrizes AN apresentaram taxa de prenhez de 92,2% contra 29,1% para CN, 22,6% para SC e 1,1% para NE. Na prenhez convencional, matrizes AN obtiveram 99,4%, 98,8% para CN, 84,4% para SC e 80,0% para NE. A reconcepção das matrizes AN foi 86,3%, 75,1% de CN, 49,6% de NE e 43,6% de SC. Matrizes AN tiveram menor média de idade ao primeiro parto em meses, 26,36±0,79, contra 31,33±0,86 para CN, 33,51±0,98 para SC e 38,08±0,74 para NE. Para peso ao desmame, crias three-cross das AN pesaram mais que as F1 das NE, por volta de 19%. Para relação de peso ao desmame, não houve diferenças estatísticas entre GG. Matrizes AN foram superiores às demais nos aspectos reprodutivos e produtivos, seguidas das matrizes CN

Taxonomic revision of the genus Lobophora (Dictyotales, Phaeophyceae) based on morphological evidence and analyses rbcL and cox3 gene sequences

A taxonomic revision of Lobophora based on molecular phylogenetic analyses of rbcL and cox3 gene sequences as well as anatomical observations was carried out, mostly based on specimens collected from eastern Asia and southeastern Australia. In the molecular phylogenetic analyses, nine major clades supported by high bootstrap values were recognized. In combination with evaluation of morphological characters, four clades were concluded to be new species. The Australian species L. australis sp. nov. possessed erect thalli with sporangial sori scattered on the ventral surface and had a closer phylogenetic relationship with another Australian species, L. nigrescens, but it was distinguished from the latter in having fewer layers of cortical cells and smaller sporangia. The Asian species L. crassa sp. nov., L. pachyventera sp. nov. and L. asiatica sp. nov. possessed decumbent thalli with sporangia scattered on the dorsal surface. Among the three prostrate species, L. crassa had a considerably thicker thallus with four to five cortical layers, L. asiatica had a thinner thallus with two cortical layers, and L. pachyventera differed from another two species by its three layered ventral cortex and well-developed anchoring rhizoids.Zhongmin Sun, Takeaki Hanyuda, Phaik-Eem Lim, Jiro Tanaka, Carlos F.D. Gurgel and Hiroshi Kawa