Genetics of resistance to soybean cyst nematode, Heterodera glycines ichione (Race 3), in a brazilian soybean population

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distribution of the Bari-I transposable element in stable hybrid strains between Drosophila melanogaster and Drosophila simulans and in Brazilian populations of these species

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Capacidade de combinação de características de produção de ovos de linhagens de matrizes de frango de corte, usando análise de componentes principais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo dos cortes da carcaça de cordeiros Santa Inês puros e cruzas Santa Inês com Texel, Ile de France e Bergamácia

Foram utilizados 103 cordeiros, machos e fêmeas, Santa Inês puros (SS) e cruzas Santa Inês com Texel (TS), Ile de France (FS) e Bergamácia (BS), confinados em gaiolas individuais. Os cordeiros foram abatidos em quatro pesos: 15,0; 25,0; 35,0 e 45,0 kg de peso vivo. Após o abate e resfriamento da carcaça, foram feitos os seguintes cortes e calculadas as porcentagens em relação ao peso da carcaça fria: pescoço (PP), costela/fralda (PCF), costeleta (PC), lombo (PL), paleta (PPA) e perna (PPE), sendo esses dois últimos sem os braços. Os pescoços praticamente não variaram com o aumento dos pesos de abate. Os pescoços dos cordeiros TS e FS foram menores, comparados aos dos cordeiros SS e BS, na maioria dos pesos de abate estudados. A paleta também não variou com o aumento dos pesos de abate, havendo tendência para diminuição. Aos 45 kg, os cordeiros TS e FS apresentaram PPA maiores em relação aos cordeiros SS e BS. Nos outros pesos de abate, praticamente não houve diferenças para PPA entre os grupos genéticos. A costela/fralda elevou-se com o aumento dos pesos de abate, sendo que, em pesos de abate elevados, os cordeiros TS mostraram maiores proporções. Para a PC, praticamente não houve diferenças entre os pesos de abate. As fêmeas FS, entretanto, aos 35 e 45 kg, apresentaram menores PCF que os machos FS. O lombo tendeu a elevar-se com o aumento dos pesos de abate, mas foram detectadas diferenças para os animais abatidos aos 15 kg, em relação aos outros pesos de abate. Entre os grupos genéticos, praticamente não houve diferenças para PL. As pernas diminuíram com o aumento dos pesos de abate. Aos 35 kg de peso vivo, os cordeiros machos TS e as fêmeas FS obtiveram melhores PPE em relação aos outros grupos genéticos.

Desempenho de cordeiros Santa Inês puros e cruzas Santa Inês com Texel, Ile de France e Bergamácia

O trabalho foi desenvolvido com o objetivo de estudar o efeito do sexo dos animais, do grupo genético e do peso de abate no desempenho de animais confinados. Foram utilizados 103 cordeiros, machos e fêmeas, Santa Inês puros (SS) e cruzas Santa Inês com Texel (TS), Ile de France (FS) e Bergamácia (BS), confinados em gaiolas individuais. Mediram-se a dieta fornecida e as sobras diárias, para cálculo do consumo de matéria seca (MS), energia metabolizável (EM), proteína digestível (PD) e fibra em detergente neutro (FDN). Os cordeiros foram abatidos em quatro pesos: 15, 25, 35 e 45 kg de peso vivo. Avaliaram-se o ganho de peso diário (GPD), o número de dias no confinamento (ND), a conversão alimentar (CA) e o consumo de MS, PD, em e FDN, nas três fases de crescimento: 15 a 25 kg (1), 25 a 35 kg (2) e 35 a 45 kg (3). Também foram avaliados as idades de abate (IA), o peso do corpo vazio (PCVZ) e rendimento de carcaça (RC). Aos 35 e 45 kg, os cordeiros TS e FS apresentaram IA inferiores e as cordeiras SS, IA superiores. O ND dos cordeiros BS de 35 a 45 kg foi maior que dos TS. Aos 35 e 45 kg, o PCVZ dos cordeiros TS e FS foram menores. Os melhores GPD foram dos cordeiros TS, seguidos do FS e SS. Os consumos de MS, PD, em e FDN foram semelhantes entre os grupos genéticos, nas fases 1 e 2 de crescimento. Verificou-se que os cordeiros TS tenderam a aumentar o consumo, com o incremento de peso, enquanto os outros grupos tenderam a diminuir. A CA elevou-se com o aumento de peso, com exceção dos machos FS. Os machos não apresentaram diferenças na CA entre os grupos genéticos, entretanto, as fêmeas TS e FS apresentaram valores melhores. Aos 35 e 45 kg, as fêmeas apresentaram maiores RC que os machos. Aos 35 kg, os melhores RC foram dos machos TS.

Influence of genotype on the quality of sheep leather

The objective of this study was to evaluate the influence of crossings between sheep breeds on the intrinsic quality of leather. It was used the skins of 36 lambs (18 females and 18 males), resulting from crosses between ewes of a native breed from the Brazilian state of Mato Grosso do Sul and rams of the same native breed as well as the Texel and Santa Inês genetic groups. The animals were raised in confinement until slaughter weight, from 28 to 32 kg. After slaughter, samples were taken from the skins for histological analysis. The skins were tanned with chromium, retanned and greased. It was taken from the leather samples for electromicrographs and for tests for tensile and tear strength (intrinsic quality). Morphological aspects from the skin as well as from the leather help to understand the results found and they evidence that breeds or crossings among breeds interfere in the intrinsic quality of leather and skin of sheep.

The distribution of the P-M hybrid dysgenesis system in Drosophila melanogaster strains from Brazil

Wild-caught flies of Drosophila melanogaster from seven natural populations of extreme regions of Brazil (Sao Luis, MA; Teresina, PI; Rio Cipo, MG; Maringa, PR; Sao Jose do Rio Preto, SP; Joinville, SC; and Porto Alegre, RS) were studied with the purpose of evaluating hybrid dysgenesis due to mobilization of P elements and the regulatory capacity of the strains' cytotypes. Diagnostic crosses were made and the strains classified according to their P-M phenotypes. Four strains were classified as moderate P (MA, MG, PI, and SP), two as Q (PR and RS) and one as M' (SC). Females of southern strains (PR, SC, and RS) presented in A crosses lower degrees of gonadal dysgenesis scores than those from northern strains (MA and PI).

Debris perturbed by radiation pressure: relative velocities across circular orbits

In the present work we consider a dynamical system of mum size particles around the Earth subject to the effects of radiation pressure. Our main goal is to study the evolution of its relative velocity with respect to the co-planar circular orbits that it crosses. The particles were initially in a circular geostationary orbit, and the particles size were in the range between 1 and 100 mum. The radiation pressure produces variations in its eccentricity, resulting in a change in its orbital velocity. The results indicated the maximum linear momentum and kinetic energy increases as the particle size increases. For a particle of 1 mum the kinetic energy is approximately 1.56 x 10(-7) J and the momentum is 6.27 x 10(-11) kg m/s and for 100 mum the energy is approximately 1.82 x 10(-4) J and the momentum is 2.14 x 10(-6) kg m/s. (C) 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Identification of QTLs associated with citrus resistance to Phytophthora gummosis

Citrus gummosis, caused by Phylophthora spp., is an important citrus disease in Brazil. Almost all citrus rootstock varieties are susceptible to it to some degree, whereas resistance is present in Poncirus trifoliata, a closely related species. The objective of this study was to detect QTLs linked to citrus Phylophthora gummosis resistance. Eighty individuals of the F, progeny, obtained by controlled crosses between Sunki mandarin Citrus sunki (susceptible) and Poncirus trifoliata cv. Rubidoux (resistant), were evaluated. Resistance to Phytophthora parasitica was evaluated by inoculating stems of young plants with a disc of fungal mycelia and measuring lesion lengths a month later. Two QTLs linked to gummosis resistance were detected in linkage groups I and 5 of the P. trifoliala map, and one QTL in linkage group 2 of the C sunki map. The phenotypic variation explained by individual QTLs was 14% for C sunki and ranged from 16 to 24% for P. trifoliala. The low character heritability (h(2) = 18.7%) and the detection of more than one QTL associated with citrus Phytophthora gummosis resistance showed that inheritance of the resistance is quantitative.

Exhumation of high-pressure granulites of the Guaxupe Complex, southeastern Brazil

This paper describes tectonic and metamorphic features of Precambrian rocks from the Guaxupe Complex and Varginha Shear Zone (VSZ) near the city of Guaxupe in the southern part of the Sao Francisco Craton, southeastern Brazil. The VSZ separates the metasediments of Araxa Group to the north from the granulites of Guaxupe Complex to the south. The sinistral transcurrent VSZ crosses the entire area striking approximately E-W, bending towards SE in the eastern part. Because of this bend, transpressional movement occurred, facilitating the exhumation of the garnet-rich rocks of the deepest exposed part of the granulite-facies terrane.In the garnet granulites the highest pressure-temperature conditions recorded are approximately 1040 degreesC and 14.4 kbar. The rocks underwent decompression from 14.0 kbar to 8.0 kbar, cooling from 980 degreesC to 710 degreesC, the retrograde path following the boundary between the kyanite and sillimanite stability fields. This interval is interpreted to record the uplift of the lower crustal granulite-facies terrane and re-equilibration during magmatic intrusions. For the felsic granulites an interval of 700-810 degreesC and 8.0-11.5 kbar was attained, also pointing to regional decompression.The granulites of the Guaxupe Complex comprise a medium- to high-pressure lower-crustal terrane, with local occurrences of higher-pressure garnet-rich gneisses, which were uplifted along a transpressional segment of the VSZ. Copyright (C) 2000 John Wiley & Sons, Ltd.

Molecular analysis of the rDNA ITS-1 intergenic spacer in Drosophila mulleri, D-arizonae, and their hybrids

We analyzed the ITS-1 spacer region of the rDNA in Drosophila mulleri and D. arizonae, two sibling species belonging to the mulleri complex (repleta group) and in hybrids obtained in both cross directions. In spite of several previous studies showing the incompatibility of crosses involving D. arizonae females and D. mulleri males, we were able to obtain hybrids in this direction. Complete ITS-1 region was amplified using primers with homology at the 3'-end of the 18S rDNA and the 5'-end of the 5.8S rDNA genes. Our data demonstrated that D. mulleri and D. arizonae can be differentiated as they present a difference in length for the ITS-1 region. The amplified fragment for this region in D. mulleri has a length of 600 bp, whereas in D. arizonae this fragment is about 500 bp. It was also observed that male and female hybrids obtained in both cross directions present two amplified fragments, confirming the location of the ribosomal cistrons in the X chromosomes and microchromosomes of both parental species.

DIFFERENTIATION OF DROSOPHILA-SERIDO (ISOFEMALE LINE A95F3) AND D-KOEPFERAE (ISOFEMALE LINE B20D2) - REPRODUCTIVE ISOLATION, DEVELOPMENT TIME AND POLYTENE CHROMOSOME-BANDING PATTERNS

Drosophila serido is considered to be a superspecies consisting of two species: D. serido, from Brazil and D. koepferae from Argentina and Bolivia. However this probably does not express the entire evolutionary complexity of its populations. Isofemale lines A95F3 (from Brazil) and B20D2 (from Argentina), at present representing, respectively, the first and second species, were analyzed for fertility and fecundity in pair-mating intracrosses and intercrosses, as well as for development time, banding patterns and asynapsis of polytene chromosomes in the isofemale lines and their hybrids.Although variations in experimental conditions resulted in some variability in the results, in general A95F3 fertility and fecundity were lower than in B20D2. Intercrosses of A95F3 females and B20D2 males showed lower fertility and fecundity than the reciprocal crosses, following more closely characteristics of the mother strains. This is in contrast to the results obtained by Fontdevilla et al. (An. Entomol. Soc. Amer. 81: 380-385, 1988) and may be due to the different geographic origin of D. serido strains they used in crosses to B20D2. This difference and others cited in the literature relative to aedeagus morphology, karyotype characteristics, inversion polymorphisms and reproductive isolation strongly indicate that A95F3 and D. serido from the State of Bahia, Brazil are not a single evolutionary entity, reinforcing the idea of greater complexity of the superspecies D. serido than is known today.The reproductive isolation mechanisms found operating between A95F3 and B20D2 were prezygotic and postzygotic, the latter included mortality at the larvae stage in both directions of crosses and sterility of male hybrids in intercrosses involving B20D2 females and A95F3 males. The two isofemale lines differed in egg-adult development time, which was also differently affected by culture medium composition.A95F3 and B20D2 also showed differences in the banding patterns of proximal regions of polytene chromosomes 2, 3 and X, a fixed inversion in chromosome 3 (here named 3t), apparently not described previously, and a high degree of asynapsis in hybrids.These observations, especially those related to reproductive isolation and chromosomal differentiation (including the karyotype, previously described, and the differentiation of banding patterns, described in this paper), as well as the extensive asynapsis observed in hybrids reinforces the distinct species status of A95F3 and B20D2 isofemale lines.

Anatomical aspects of the lacrimal gland of the tufted capuchin (Cebus apella)

In the tufted capuchin (Cebus apella) the main lacrimal gland is composed of 2 distinct portions with an intraorbital and extraorbital localisation, interconnected by a bridge of glandular tissue which crosses the lateral orbital wall through the lateral orbital fissure located in the sphenozygomatic suture. The intraorbital lacrimal gland is flattened and extremely thin, with a variable outline. It lies on the upper and outer third of the globe of the eye, and the aponeurosis and the belly of the lateral rectus muscle, extending antero-posteriorly from the upper lateral angle of the orbit midway along the orbital cavity. The extraorbital lacrimal gland is compact, halfmoon-shaped, with 3 surfaces, 3 borders and 2 extremities. It lies in the temporal fossa between the temporalis muscle and the temporal surface of the zygomatic bone, fitting into a depression in this bone, and totally surrounded by adipose tissue. The secretory cells have a flocculent appearance and either low or high density. They possess a basal region containing the nucleus and rich in granular endoplasmic reticulum, and an apical region filled with secretory granules varying in size, form and density.

Reproductive compatibility and chromosome pairing in the Drosophila buzzatii complex

Fertility (percentage of fertile crosses) and the degree of synapsis in salivary gland chromosomes in isofemale lines of Drosophila buzzatii, D. serido, D. koepferae and D. seriema were analysed. D. buzzatii was completely sterile in intercrosses with strains from the other species except for D. koepferae. The other species intercrossed to a greater or lesser degree, but also differed between crossing directions. Homologous pairing in salivary gland preparations of strains and hybrids conformed with the data on fertility. The lowest degree of synapsis was present in hybrids between D. koepferae and D. buzzatii, D. seriema and D. koepferae and D. koepferae and D. serido. These species also exhibited the lowest degree of reproductive compatibility. Hybrids between D. seriema and D. serido showed an intermediate degree of synapsis (pairing absent in the proximal and distal chromosome ends), as well as fertility greater than that found in the other interspecific crosses. Results of the fertility of crosses involving strains of a single species, compared with data in the literature, indicated that intraspecific divergence occurred in D. serido and D. koepferae.

The strands of the F ring disturbed by its closest satellites

Some Voyager images showed that the F ring of Saturn is composed of at least four separate, non-intersecting, strands covering about 45 degrees in longitude. According to Murray et al. [Murray, C.D., Gordon, M., Giuliatti Winter, S.M. Unraveling the strands of Saturn's F ring. Icarus 129, 304, 1997.] this structure may be caused by undetected satellites embedded in the gaps.Due to precession, the satellites Prometheus and Pandora and the ring particles can experience periodic close encounters. Giuliatti Winter et al. [Giuliatti Winter, S.M, Murray, C.D., Gordon, M. Perturbations to Saturn's F-ring strands at their closest approach to Prometheus. Plan. Space Sciences, 48, 817, 2000.] analysed the behaviour of these four strands at closest approach with the satellite Prometheus. Their work suggests that Prometheus can induce the ring particles to scatter in the direction of the planet, thus increasing the population of small bodies in this region.In this work we analysed the effects of Prometheus on the radial structure of Saturn's F ring during the Voyager and early Cassini epochs. Our results show that at Voyager epoch Prometheus, and also Pandora, had a negligible influence in the strands. However, during the Cassini encounter Prometheus could affect the strands significantly, scattering particles of the inner strand in the direction of the planet. This process can contribute to the replenishment of material in the region between the F ring and the A ring, where two rings have recently been discovered [Porco, C. et al. Cassini imaging science. Initial results on Saturn's rings and small Satellites. Science, 307, 1226, 2005].We also analyse the behaviour of undetected satellites under the effects of these two satellites by computing the Lyapunov Characteristic Exponent. Our results show that these satellites have a chaotic behaviour which leads to a much more complex scenario. The new satellite S/2004 S6 also presents a chaotic behaviour with can alter the dynamic of the system, since this satellite crosses the orbit of the strands. (C) 2006 COSPAR. Published by Elsevier Ltd. All rights reserved.