Gas exchange rates at different vapor pressure deficits and water relations of 'Pera' sweet orange plants with citrus variegated chlorosis (CVC)

Net photosynthesis (A) and transpiration rates (E), stomatal conductance (g), water use efficiency (WUE), intrinsic water use efficiency (IWUE) and internal leaf CO2 concentration (C) in response to different vapor pressure deficit (1.2 and 2.5 kPa) were investigated in 'Pera' sweet orange plants affected by citrus variegated chlorosis (CVC), a disease caused by Xylella fastidiosa. All plants were well watered and leaf water potential (Pw) was also measured by the psychrometric technique. Results showed that healthy plants responded to higher vapor pressure deficit (VPD), lowering its net photosynthesis and transpiration rates, and stomatal conductance. However, diseased plants presented no clear response to VPD, showing lower A, E and g for both VPDs studied and very similar values to these variables in healthy plants at the highest VPD. Internal leaf CO2 concentration also decreased for healthy plants when under the highest VPD, and surprisingly, the same pattern of response was found in plants with CVC. These results, the lower Psi(w) and higher WUE values for diseased plants, indicated that this disease may cause stomatal dysfunction and affect the water resistance through xylem vessels, which ultimately may play some role in photosynthetic metabolism. (C) 2003 Elsevier B.V. B.V. All rights reserved.

CO2 assimilation, photosynthetic light response curves, and water relations of 'Pêra' sweet orange plants infected with Xylella fastidiosa

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

Leaf heliotropism in Styrax camporum Pohl from the Brazilian cerrado: distinct gas exchange and leaf structure, but similar leaf temperature and water relations

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Factors affecting somatic cell counts and their relations with milk and milk constituent yield in buffaloes

Data concerning daily milk yield (MY), percentage of milk fat (%F), protein (%P), lactose (%LT), and total solids (%TS), and somatic cell counts (SCC) for a herd of 222 Murrah buffalo reared in the state of São Paulo, Brazil, were collected monthly from 1997 to 2000 in order to study the factors affecting SCC and their relation to milk production and constituents during lactation. SCC decreased in the second month of lactation and increased thereafter, up to the ninth month of lactation. The interaction of month of lactation x order of calving was significant. Mean MY observed during the first month of lactation was 6.87 kg, which increased to 7.65 kg during the second month, and then decreased until the ninth month of lactation (3.83 kg). During the different months of lactation, %F, %P, %LT, and %TS ranged from 6.28 to 8.38%, 4.05 to 4.59%, 4.96 to 5.34%, and 16.94 to 18.55%, respectively. Calving year, calving order, and order of month of lactation significantly affected MY, %F, %P, %LT, and %TS. The regression coefficients of transformed SCC on MY and %LT were negative and significant during all months of lactation, showing that milk and lactose yield decreased with increased transformed SCC, causing losses to buffalo milk producers.

Infection patterns of Paradollfusnema amphisbaenia (Nematoda: Cosmocercidae) in a population of Amphisbaena wuchereri (Squamata: Amphisbaenidae) from Minas Gerais state, south-eastern Brazil, and its relations with host size, sex and fat body mass

Specimens (n= 41) of the amphisbaenid Amphisbaena wuchereri taken from a population in Minas Gerais state, south-eastern Brazil, were examined for gastrointestinal parasites. A single nematode species was found, Paradollfusnema amphisbaenia. This was a new host record for this nematode species. This parasite was encountered in the large intestine (prevalence of 100%), in the stomach (prevalence of 2%) and in the small intestine (prevalence of 7.3%). The intensity of infection ranged from 1 to 457 individual parasites per host and was positively correlated with body size of both male and female amphisbaenians. The discrepancy index (D) indicated that P. amphisbaenia tended to an even distribution in this host population. The nematode, which did not affect fat body mass, induced inflammatory infiltrations in the small intestine, indicating that the parasites might injure the host's organs. Copyright © Cambridge University Press 2012.

O debate modernidade / pós-modernidade e a crise socioambiental: um estudo sobre teses e dissertações brasileiras em educação ambiental

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Soil greenhouse gas emissions and their relations to soil attributes in a sugarcane area

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

Memória de velhas professoras: a natureza e a relação sociedade-natureza

Este artigo tem como objetivo identificar, a partir da memória de velhas professoras, as concepções de natureza e de relação sociedade-natureza presentes nos depoimentos de professoras que atuaram na rede pública estadual de uma cidade do interior do estado de São Paulo, nas décadas de 1960 e 1970. Constatou-se, por meio das leituras das narrativas, que as professoras apresentam a natureza por meio de diferentes concepções. No que diz respeito à relação sociedade-natureza, evidencia-se a relação conflituosa que se estabelece entre o homem e a natureza. No geral, o homem foi apresentado como aquele que destrói a natureza, caracterizado pelas professoras como ruim e ignorante. Tentar compreender como a natureza e a relação sociedade-natureza se fazem presentes na memória dessas professoras pode contribuir para a construção de novas formas de relação sociedade-natureza nos dias atuais.

FRACTAL CHARACTERISTICS OF THE HORIZONTAL MOVEMENT OF WATER IN SOILS

Observed deviations from traditional concepts of soil-water movement are considered in terms of fractals. A connection is made between this movement and a Brownian motion, a random and self-affine type of fractal, to account for the soil-water diffusivity function having auxiliary time dependence for unsaturated soils. The position of a given water content is directly proportional to t(n), where t is time, and exponent n for distinctly unsaturated soil is less than the traditional 0.50. As water saturation is approached, n approaches 0.50. Macroscopic fractional Brownian motion is associated with n < 0.50, but shifts to regular Brownian motion for n = 0.50.

Política de desenvolvimento e estruturação do espaço regional da área da Bodoquena em Mato Grosso do Sul

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

O ensino de história e geografia nos anos iniciais numa rede municipal de ensino: um estudo de caso

The present research aims to identify conceptions that teachers and students of the early years have in relation to the disciplines of history and geography. The site chosen for the survey was a municipal school in the city of Lençóis Paulista, in São Paulo. The work's theme was chosen after observing a minimization of the teaching of the contents of the above-mentioned disciplines at the expense of mathematical content and mother tongue. In addition, there were difficulties arising from the standardization of education , such as teaching network uses material apostilled . The survey data , together with literature review was conducted with students and teachers in the early years who participated in a semistructured interview . Authors like Callai (1999 and 2005), Cavalcanti (2005 and 1998) and Burke (1992) theoretically supports the research . They have in common a new conception of education that values the small deeds that result in major events. The student, in this view, plays an important role as a subject of social transformation. The research has favored both the analysis of the conceptions of teachers and students, assisting in reflection on teaching practices, but also led to reflect on the training of teachers. The research shows us that the type of material used and the practice adopted may impair the access of students to the language of nature and society