Universidade Federal de Viçosa

About: Universidade Federal de Viçosa is a education organization based out in Viçosa, Brazil. It is known for research contribution in the topics: Population & Biology. The organization has 16012 authors who have published 26711 publications receiving 353416 citations.

Universal fluctuations in the growth of semiconductor thin films

Abstract: Scaling of surface fluctuations of polycrystalline CdTe/Si(100) films grown by hot-wall epitaxy are studied. The growth exponent of surface roughness and the dynamic exponent of the autocorrelation function in the mound growth regime agree with the values of the Kardar-Parisi-Zhang (KPZ) class. The scaled distributions of heights, local roughness, and extremal heights show remarkable collapse with those of the KPZ class, giving an experimental observation of KPZ distributions in $2+1$ dimensions. Deviations from KPZ values in the long-time estimates of dynamic and roughness exponents are explained by spurious effects of multipeaked coalescing mounds and by effects of grain shapes. Thus, this scheme for investigating universality classes of growing films advances over the simple comparison of scaling exponents.

Comparison of Two Methods for Estimating Leaf Area Index on Common Bean

Abstract: Measurement of leaf area index (LAI) is important in studies of plant growth. Based on this concept, the analysis of crop growth has moved from classical growth analysis to mechanistic models, via functional growth analysis. Leaf area index is a major variable in mechanistic crop growth models and in models that attempt to simulate loss caused by pathogens. A field experiment was carried out from May through August 1998, using common bean (Phaseolus vulgaris L. cv. Carioca), in a randomized complete block design with two methods of LAI evaluation and three replications. The objective of this study was to compare the applicability of the LAI-2000 Plant Canopy Analyzer with the central leaflet width method used to estimate LAI in common bean. The high correlation (r 2 = 0.97) observed between the two methods used to estimate LAI shows agreement between them. The results of this study indicated that the LAI-2000 can be used to estimate the LAI of common bean.

Wheat blast: from its origins in South America to its emergence as a global threat.

Abstract: Wheat blast was first reported in Brazil in 1985 It spread rapidly across the wheat cropping areas of Brazil to become the most important biotic constraint on wheat production in the region The alarming appearance of wheat blast in Bangladesh in 2016 greatly increased the urgency to understand this disease, including its causes and consequences Here, we summarize the current state of knowledge of wheat blast and aim to identify the most important gaps in our understanding of the disease We also propose a research agenda that aims to improve the management of wheat blast and limit its threat to global wheat production