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41.
Primo Anacláudia Alves Araújo Maria Diana Melo Silva Karla da Fonseca Silva Ludmyla Araújo Pereira Graziella de Andrade Carvalho Fernandes Francisco Éden Paiva Pompeu Roberto Cláudio Fernandes Franco Natale William de Souza Henrique Antunes 《Agroforestry Systems》2021,95(8):1459-1464
Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in... 相似文献
42.
Ana Alves Antonio Santos Philippe Rozenberg Luc E. Paques Jean-Paul Charpentier Manfred Schwanninger José Rodrigues 《Wood Science and Technology》2012,46(1-3):157-175
Wood density is defined as the ratio of mass to volume and therefore in principle it should be possible to calculate a unique partial least squares regression (PLS-R) model for several species. PLS-R models for wood density based on X-ray microdensity data were calculated for each species Pinus pinaster and Larix × eurolepis and for both species together. After cross-validation and test set validation the data sets were combined and final models were calculated. The common model gave a residual prediction deviation (RPD) of 3.1, a range error ratio (RER) of 11.7, and a SEP/SEC of 1.06. The single models for Pinus pinaster and Larix?×?eurolepis gave RPD’s of 3.5 and 3.2, RER’s of 13 and 11, and a SEP/SEC of 1.2. To the best knowledge of the authors all obtained PLS-R models are the first ones that fulfil the requirements according to AACC Method 39-00 (AACC in AACC Method, 39-00:15, 1999) to be used at least for screening (RPD?≥?2.5). Although this method and the defined limits were developed for the analysis of grains they can be used as a rough rule of thumb until limits for wood are available. The improvement of the PLS-R models, compared to published results, might be due to three facts (1) the higher number of scans collected for a single spectrum, (2) that the samples were better represented by the NIR spectra and X-ray microdensity values, and (3) that the sites for the measurement of NIR spectra and X-ray microdensity were coincided as strictly as possibly. 相似文献
43.
Caroline Carvalho de Oliveira Fabiana Villa Alves Roberto Giolo de Almeida Érick Lemes Gamarra Severino Delmar Junqueira Villela Paulo Gustavo Macedo de Almeida Martins 《Agroforestry Systems》2018,92(6):1659-1672
The objective was to evaluate the animal thermal comfort indices from two integrated crop-livestock-forestry (ICLF) systems. For this, temperature–humidity index (THI), black globe temperature and humidity index (BGHI), and the radiant thermal load (RTL) were assessed. Two ICLF (ICLF-1 and ICLF-2) systems and one control system were established. On the ICLF systems, the arboreal component was the eucalyptus tree (Eucalyptus grandis × Eucalyptus urophylla; H13 clone), planted in simple wide-spaced rows. The ICLF-1 system had a tree spacing of 14 × 2 m with 357 trees per hectare, and the ICLF-2 had a tree spacing of 22 × 2 m with 227 trees per hectare. The control system had five scattered native trees per hectare, pertaining to Gochnatia and Dipteryx species. The forage component in all three systems was piatã-grass (Brachiaria brizantha cv. BRS Piatã). The experimental design was a randomized block in a sub-subplot design scheme with four replications. The presence of shade provided by the trees offered better conditions of animal comfort when compared with the condition of full sun. The ICLF-1 system, with higher tree density, provided better indicators for thermal comfort, THI, BGHI, and RTL when compared with the condition of full sun, while ICLF-2 was no different than ICLF-1 for BGHI. 相似文献
44.
Élvis da Silva Alves Lineu Neiva Rodrigues Fernanda Laurinda Valadares Ferreira 《Journal of Agronomy and Crop Science》2023,209(1):176-187
Soil evaporation constitutes a major pathway of water loss in agriculture. Understanding its dynamics in the face of drying and soil cover is fundamental to improve both simulation models and the sustainability of production systems. Thus, the objective of this study was to estimate soil evaporation as a function of drying and percentage of soil cover. Three experiments were carried out in three different periods. In each of the periods, in parallel and in an adjacent area, an experiment was carried out to evaluate the influence of weighing micro-lysimeter (ML) height on the estimation of direct soil evaporation. The experiments were installed with a completely randomized design. For the experiments that measured evaporation as a function of cover, the treatments consisted of six different percentages of cover of the internal area of the ML (0%, 10%, 25%, 50%, 75% and 100%), with four replicates, using artificial plants to cover the soil. The experiments that estimated evaporation as a function of ML height were conducted with eight repetitions and three different ML heights (100, 200 and 300 mm). It was observed that the accumulated evaporation up to 25 days after wetting was 52% and 53% lower in micro-lysimeters with 100 mm height, compared to those with 200 and 300 mm height, respectively, for all experiments. The new model developed to calculate soil evaporation as a function of the days after wetting and percentage of soil cover showed excellent performance (NSE > 0.95). 相似文献
45.
Edenise Segala Alves Bárbara Baêsso Moura Marisa Domingos 《Water, air, and soil pollution》2008,189(1-4):61-68
Bioindicators plants are important for the evaluation of air quality and Tillandsia usneoides L., an atmospheric epiphyte bromeliad, has been used for this purpose. The present study aims at evaluate the structural pattern of the leaf of this species when exposed to urban air pollutants, and determining whether the leaves present structural parameters that could be used as indicators of such pollutants. Samples of T. usneoides were exposed in São Paulo, the biggest city of Brazil, for 8, 16 and 24 weeks, and compared with others kept in a rural area. The urban pollution of São Paulo affected the structure of the leaves of T. usneoides causing alterations, especially in the scales, density of stomata and epidermis thickness. Qualitative alterations in the mesophyll were not observed in plants exposed at the polluted sites. These structural characteristics of T. usneoides seem to account for its high tolerance to heavy metal accumulation. The percentage of anomalous scales may potentially be used as an alternative bioindicator parameter. 相似文献
46.
In this work multivariate experiments were conducted to optimize the operating conditions for inductively coupled plasma optical emission spectrometry (ICP OES) for multielemental determinations in chocolate drink powder. The operating conditions were investigated using a 2(3) central composite design, where the variables studied were radio frequency power, nebulization flow rate, and auxiliary argon flow rate. The effects of these parameters on plasma robustness and on signal to background ratio (SBR) were considered in parallel, allowing the evaluation of robustness and detectability using few and fast experiments to select the best conditions for the determination of the analytes. In this case, the proposed experiments were applied to the optimization of a method aimed at the determination of Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, P, Pb, V, and Zn in chocolate drink powder. The compromise conditions that allowed obtaining a robust and sensitive analytical method were radio frequency power of 1200 W, nebulization flow rate of 0.6 L/min, and auxiliary argon flow rate of 0.3 L/min. Using these conditions, recoveries between 95 and 105% and relative standard deviations lower than 5% were obtained for the majority of the analytes. The proposed method was successfully applied to the analysis of 15 samples of chocolate drink powder. The highest concentrations of metallic species were found in diet and light products. 相似文献
47.
Eveline Teixeira Caixeta Aluízio Borém Samir de Azevedo Fagundes Silvia Niestche Everaldo Gonçalves de Barros Maurílio Alves Moreira 《Euphytica》2003,134(3):297-303
The existence of genetic variability for angular leaf spot (ALS) resistance in the common bean germplasm allows the development
of breeding lines resistant to this disease. The BAT 332 line is an important resistance source to common bean ALS. In this
work we determined the inheritance pattern and identified RAPD markers linked to a resistance gene present in BAT 332. Populations
F1, F2,BCs and BCr derived from crosses between BAT 332 and cultivar Rudá were used. Rudá is a commercial cultivar with carioca
type grains and susceptible to ALS. The resistance of BAT 332 to race 61.41 of the pathogen was confirmed. Segregation analysis
of the plants indicated that a single dominant gene confers resistance. For identification of RAPD markers linked to the resistance
gene, bulk segregant analysis (BSA) was used. Two RAPD markers,OPAA07950 and OPAO12950, linked in coupling phase at 5.10 and 5.83 cM of this gene, respectively, were identified. These molecular markers are important
for common bean breeders and geneticists as source of genetic information and for marker assisted selection in breeding programs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
Antonio Carlos Centeno Cordeiro Antônio Alves Soares Magno Antonio Patto Ramalho Paulo Hideo Nakano Rangel 《Euphytica》2003,132(1):79-86
The effect of 0, 1, 2, 3 and 4 intercross cycles using genetic male sterility on the mean yield and genetic variability of
the CNA 5 irrigated rice synthetic population was assessed studying 300 S0:2 (1998/99) and S0:3 (1999/00) families grown in two locations (Lambari, MG and Goianira, GO). Each intercross was investigated using a 8 × 8 triple
lattice design experiment containing 60 families and four control cultivars. Five experiments were carried out per location
and generation, totaling 20 experiments. Individual, combined over locations, combined over generations and combined over
locations and generations analyses of variance were performed. Linear regression equations were fitted to data of each location
and generation as well as, genetic and phenotypic parameters were estimated. An average increase of 3.91% in grain yield was
obtained with the increase in the number of intercrosses. However, when genetic gains obtained from selection of the five
and ten highest yielding families were considered, negative b estimates were always obtained, suggesting a tendency of gain
increase reduction with the increase in the number of intercrosses. This was confirmed by the analysis of the means of the
best families, since increases in the number of intercrosses did not result in selection of families with greater mean grain
yield. The estimates of the genetic variances and heritabilities did not suggest an increase in genetic variability with the
increase in intercross cycles. Therefore, carrying out intercrosses on the base population did not improve the results of
the irrigated rice recurrent selection program.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
49.
Ana Lilia Alzate-Marin Marcia Regina Costa Klever Marcio Arruda Everaldo Gonçalves de Barros Maurilio Alves Moreira 《Euphytica》2003,133(2):165-169
Ouro Negro (Honduras 35) is a highly productive Mesoamerican black seeded bean cultivar that possesses a major dominant gene
conferring resistance to anthracnose (causal organism Colletotrichum lindemuthianum). In this work the anthracnose resistance gene present in Ouro Negro was characterized by studying allelic relationships
to the following previously characterized anthracnose resistance genes (cultivars): Co-1 (MDRK), Co-1
2 (Kaboon), Co-1
3 (Perry Marrow), Co-2 (Cornell 49-242), Co-3 (Mexico 222), Co-4 (TO), Co-4
2 (SEL 1308), Co-5 (SEL1360), Co-6 (AB 136), and the resistance genes present in PI 207262 and Widusa. In addition, we determined the resistance spectrum of
Ouro Negro in relation to 19 pathotypes of C. lindemuthianum. The allelism tests confirmed that the dominant anthracnose resistance gene present in Ouro Negro is positioned at a locus
distinct from those with which it was compared. We propose that this new gene be named Co-10. The inoculation of Ouro Negro with the 19 pathotypes of C. lindemuthianum demonstrated that Co-10 confers resistance to pathotypes 23, 64, 67, 73, 81, 83, 87, 89, 95, 102, 117, 119, 343, 453, 1033, 1545 and 1600. The identification
of Co-10 is an important contribution to bean breeding programs that are in constant need of new sources of resistance to anthracnose.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献