Institution
Universidade Federal de Viçosa
Education•Viçosa, Brazil•
About: Universidade Federal de Viçosa is a education organization based out in Viçosa, Brazil. It is known for research contribution in the topics: Population & Dry matter. The organization has 16012 authors who have published 26711 publications receiving 353416 citations.
Topics: Population, Dry matter, Germination, Species richness, Soil water
Papers published on a yearly basis
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TL;DR: Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity, and was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco.
Abstract: Coffee (Coffea arabica L.) plants were grown in small (3-L), medium (10-L) and large (24-L) pots for 115 or 165 d after transplanting (DAT), which allowed different degrees of root restriction. Effects of altered source : sink ratio were evaluated in order to explore possible stomatal and non-stomatal mechanisms of photosynthetic down-regulation. Increasing root restriction brought about large and general reductions in plant growth associated with a rising root : shoot ratio. Treatments did not affect leaf water potential or leaf nutrient status, with the exception of N content, which dropped significantly with increasing root restriction even though an adequate N supply was available. Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity. At 165 DAT contents of hexose, sucrose, and amino acids decreased in plants grown in smaller pots, while those of starch and hexose-P increased in plants grown in smaller pots. Photosynthetic rates were negatively correlated with the ratio of hexose to free amino acids, but not with hexose content. Activities of acid invertase, sucrose synthase, sucrose-P synthase, fructose-1,6-bisphosphatase, ADP-glucose pyrophosphorylase, starch phosphorylase, glyceraldehyde-3-P dehydrogenase, PPi : fructose-6-P 1-phosphotransferase and NADP : glyceraldehyde-3-P dehydrogenase all decreased with severe root restriction. Glycerate-3-P : Pi and glucose-6-P : fructose-6-P ratios decreased accordingly. Photosynthetic down-regulation was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco. Such a down-regulation was largely a result of N deficiency caused by growing coffee plants in small pots.
83 citations
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TL;DR: The results show there is greater species richness of culturable endophytic filamentous fungi in the leaves G. max as compared to roots, and identifies the genetic relationships among the isolated species.
83 citations
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TL;DR: In this article, the authors present and discuss students' learning process of chemical equilibrium from a modelling-based approach developed from the use of the "Model of Modelling" diagram, and support the conclusion that elements from the 'Model of Modeling' diagram, as well as methodological aspects related to the teacher's action, influenced the students learning process.
Abstract: This paper presents and discusses students’ learning process of chemical equilibrium from a modelling‐based approach developed from the use of the ‘Model of Modelling’ diagram. The investigation was conducted in a regular classroom (students 14–15 years old) and aimed at discussing how modelling‐based teaching can contribute to students learning about the main qualitative aspects concerning chemical equilibrium. The data (collected from the written material produced by the students and the video‐recording of the classes) were organised in case studies for each group of students. The discussion supports the conclusion that elements from the ‘Model of Modelling’ diagram, as well as methodological aspects related to the teacher’s action, influenced the students’ learning process.
83 citations
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TL;DR: The majority of the phosphine-resistant populations exhibited lower developmental and population growth rates than the susceptible populations indicating that phosphine resistance is associated with fitness cost in all three species, which can potentially compromise the fixation and dispersal of the resistant genotypes.
83 citations
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TL;DR: Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth.
Abstract: Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth.
83 citations
Authors
Showing all 16194 results
Name | H-index | Papers | Citations |
---|---|---|---|
José A. Teixeira | 101 | 1414 | 47329 |
J. Alfredo Martínez | 82 | 642 | 24009 |
Andrew J. Davison | 78 | 240 | 22171 |
David H. Bromwich | 75 | 291 | 21688 |
Takeji Nishikawa | 59 | 408 | 14727 |
Thierry Candresse | 59 | 403 | 11833 |
Raul Narciso C. Guedes | 55 | 378 | 10668 |
Matthias Erb | 54 | 166 | 8599 |
Arne Janssen | 53 | 179 | 8315 |
Paulo R. Guimarães | 52 | 162 | 10206 |
Antonio Reverter | 52 | 233 | 7259 |
Adriano Nunes-Nesi | 52 | 157 | 8453 |
Fermín I. Milagro | 51 | 245 | 9281 |
Svetoslav Dimitrov Todorov | 51 | 210 | 7072 |
Marcos Heil Costa | 50 | 124 | 9660 |