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81.
Glyphosate sustainability in South American cropping systems 总被引:1,自引:0,他引:1
Christoffoleti PJ Galli AJ Carvalho SJ Moreira MS Nicolai M Foloni LL Martins BA Ribeiro DN 《Pest management science》2008,64(4):422-427
South America represents about 12% of the global land area, and Brazil roughly corresponds to 47% of that. The major sustainable agricultural system in South America is based on a no-tillage cropping system, which is a worldwide adopted agricultural conservation system. Societal benefits of conservation systems in agriculture include greater use of conservation tillage, which reduces soil erosion and associated loading of pesticides, nutrients and sediments into the environment. However, overreliance on glyphosate and simpler cropping systems has resulted in the selection of tolerant weed species through weed shifts (WSs) and evolution of herbicide-resistant weed (HRW) biotypes to glyphosate. It is a challenge in South America to design herbicide- and non-herbicide-based strategies that effectively delay and/or manage evolution of HRWs and WSs to weeds tolerant to glyphosate in cropping systems based on recurrent glyphosate application, such as those used with glyphosate-resistant soybeans. The objectives of this paper are (i) to provide an overview of some factors that influence WSs and HRWs to glyphosate in South America, especially in Brazil, Argentina and Paraguay soybean cropped areas; (ii) to discuss the viability of using crop rotation and/or cover crops that might be integrated with forage crops in an economically and environmentally sustainable system; and (iii) to summarize the results of a survey of the perceptions of Brazilian farmers to problems with WSs and HRWs to glyphosate, and the level of adoption of good agricultural practices in order to prevent or manage it. 相似文献
82.
D. Archundia C. Duwig L. Spadini G. Uzu S. Guédron M. C. Morel R. Cortez O. Ramos Ramos J. Chincheros J. M. F. Martins 《Water, air, and soil pollution》2017,228(1):44
Cities in developing countries encounter rapid waves of social transformation and economic development where the environment is mostly a neglected aspect. The Katari watershed encompasses mining areas, El Alto city (one of the fastest growing urban areas in South America and the biggest in the Altiplano) as well as agricultural areas. Its outlet is Cohana Bay, one of the most polluted areas of Lake Titicaca. Here we propose an integrative approach (hydrological, physicochemical, chemical and bacterial data) to understand the pollution problem of this developing area, in which a variety of anthropogenic activities takes place. Both mining and urban areas appear to be sources of metal pollution. Nutrient and bacterial contaminations are mainly related to urban and industrial discharges. These situations have impacts in the basin from the mining area down to Cohana Bay of Lake Titicaca. Pollutant concentration patterns are highly influenced by seasonal hydrology variations. The poor quality of surface waters in the basin represents a risk for human and animal populations, as well as for the quality of aquifers located underneath El Alto city. 相似文献
83.
Rilner Alves Flores Ricardo Gomes da Silva Patrícia Pinheiro da Cunha Virgínia Damin Klaus de Oliveira Abdala Everton Martins Arruda 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):697-704
Foliar fertilization may be a viable strategy to boron supply in irrigated cropping systems with common beans (Phaseolus vulgaris), since it prevent B leaching. The aim of this work was to evaluate the economic viability and physiological parameters of the common beans production in irrigated cropping systems using sources and increasing foliar boron doses. A field experiment was carried out using an experimental block design in a factorial scheme 2?×?5?×?3, with two sources of B (boric acid and borax) and five doses: 0 (control), 2, 4, 6 e 8?kg?ha?1, with three repetitions. Foliar B applications were performed at 40 days after seeds germination, in pre-flowering stage. Physiological process (transpiration, stomatal conductance, CO2 internal concentration, net photosynthesis, and relative chlorophyll index), B level in leaves and grain yield were measured. These data were used to determine the economic viability of B fertilization in common beans. Both boric acid and borax increased B levels in common beans leaves. Borax affected some physiological process reducing stomatal conductance and increasing net photosynthesis. Using borax, the highest net photosynthesis was observed at a rate of 4?kg?ha?1, while the boric acid increased net photosynthesis linearly after increasing B doses application. An enhance of 311?kg?ha?1 in the grain yield was observed using borax related to the control (without B application); however, grain yield decreased linearly after application of increasing B doses, as boric acid. Comparing the economic viability of sources and doses of B, the highest profitability is obtained using borax at a rate of 4?kg?ha?1, which promoting a differential profit of US$534.44 per hectare compared to common beans cropping without B. 相似文献
84.
Sarah Figueiredo Martins Bonilha Renata Helena Branco Maria Eugênia Zerlotti Mercadante Joslaine Noely dos Santos Gonçalves Cyrillo Fábio Morato Monteiro Enilson Geraldo Ribeiro 《Tropical animal health and production》2017,49(3):529-535
Understanding the reasons why animals of similar performances have different feed requirements is important to increase profits for cattle producers and to decrease the environmental footprint of beef cattle production. This study was carried out aiming to identify the associations between residual feed intake (RFI) and animal performance, nutrient digestibility, and blood metabolites related to energy balance of young Nellore bulls during the finishing period. Animals previously classified as low (n?=?13) and high RFI (n?=?12), with average initial body weight of 398 kg and age of 503 days were used. Cattle were fed a high energy diet and were slaughtered when rib fat thickness measured by ultrasound between the 12th and 13th ribs reached the minimum of 4 mm. A completely randomized design was adopted, being data analyzed with a mixed model that included the random effect of slaughter group, the fixed effect of RFI class, and linear effect of the covariate feedlot time. No differences were found (p?>?0.10) between RFI classes for performance, dry matter, and nutrients intake. However, dry (p?=?0.0911) and organic matter (p?=?0.0876) digestibility tended to be lower, and digestibility of neutral detergent fiber corrected for ash and protein (p?=?0.0017), and total digestible nutrients (p?=?0.0657) were lower for high RFI animals, indicating lesser capacity of food utilization. Difference between low and high RFI animals was also found for blood cortisol at the end of the trial (p?=?0.0044), having low RFI animals lower cortisol concentrations. Differences in the ability to digest food can affect the efficiency of transforming feed into meat by Nellore cattle. 相似文献
85.
I. M. Madrid A. Mattei A. Martins M. Nobre M. Meireles 《Zoonoses and public health》2010,57(2):151-154
Clinical cases of feline sporotrichosis, originating in the Pelotas region and diagnosed at the Laboratory of Infectious Diseases (UFPel), were studied in the period from 2002 to 2006. The animals were evaluated according to the clinical forms of the mycosis, time of lesion appearance, severity of the clinical diagnosis and evolution of cutaneous lesions throughout the treatment period. Mycological analyses, carried out through direct examination, cultivation of tissue samples and exudates of feline lesions all confirmed the diagnosis of sporotrichosis in the 15 animals under study. The cutaneous dissemination form was observed in 10 animals, of which three showed prostration, anorexia and dehydration. The zoonosis occurred in 20% of case studies, and the pet owners and one attendant at a veterinary clinic were infected, developing the fixed and disseminated cutaneous forms. The treatment of mycosis was carried out with itraconazole, 10 mg kg?1, once a day, on 12 animals. The cure of the clinical symptoms was observed on 50% of the felines. This study demonstrates a good clinical response of felines with sporotrichosis, when they were treated itraconazole and calls the attention for the incidence of human sporotrichosis on people related to the veterinary activity as well as for pet owners. 相似文献
86.
The economics of dairy production are in great part dictated by the reproductive efficiency of the herds. Many studies have reported a widespread decrease in fertility of dairy cows. In a previous work ( Rocha et al. 2001 ), we found a very poor oestrus detection rate (38%), and consequently a delayed calving to 1st AI and calving to conception intervals. However, a good conception rate at 1st AI was noted (51%) resulting in a low number of inseminations per pregnancy (IAP) (1.4). Here, results from a subsequent fertility time trend assessment study carried out in the same region for cows born from 1992 to 2002 are reported. Statistical linear models were used to analyse the data. Estimate linear contrasts of least square means were computed from each model. The number of observations per studied index varied from 12 130 (culling rate) to 57 589 (non‐return rate). Mean age at first calving was 28.9 ± 0.14 months, without (p > 0.05) variation over time. There was a small, but significant (p < 0.05), deterioration of all other parameters. Non‐return rates at 90 days and calving rate at 1st AI decreased 0.3% per trimester, with a consequent increase of 0.04 IA/parturition. Oestrus detection rate decreased 0.13% per year, and calving at 1st AI and calving‐conception intervals increased 0.17 and 0.07 days/year respectively, while intercalving interval increased 1.7 days per year. From 12 130 cows calving, only 1 816 had a 4th lactation (85% culling/losses). The data was not meant to draw conclusions on the causes for the decreased fertility over time, but an increase of milk production from 6537 kg to 8590 kg (305 days) from 1996 to 2002 is probably one factor to take into consideration. Specific measures to revert or slow down this trend of decreasing fertility are warranted. Available strategies are discussed. 相似文献
87.
A Martins‐Bessa T Santos J Machado R Pinelas MA Pires R Payan‐Carreira 《Reproduction in domestic animals》2010,45(3):558-563
A 7‐year‐old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás‐os‐Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 × 3.5 cm mass located dorso‐laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post‐mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation. 相似文献
88.
Luciano Fernandes Sousa Rogério Martins Maurício Guilherme Rocha Moreira Lúcio Carlos Gonçalves Iran Borges Luiz Gustavo Ribeiro Pereira 《Agroforestry Systems》2010,79(2):189-199
This study aimed at evaluating the influence of a silvopastoral system (SPS) composed of “Aroeira” trees (Myracrodruon urundeuva) on the nutritional value of Brachiaria brizantha cv. Marandu forage grass over the rainy season. The experiment was conducted in the SPS located in the “Cerrado” biome in
Lagoa Santa County, Minas Gerais state, Brazil, in the agricultural year of 2004–2005. It was evaluated the influence of “Aroeira”,
whose density in the area was 140 trees/ha, on the following parameters of the B. brizantha cv. Marandu forage grass: forage mass harvest above stubble height, morphogenic attributes, bromatological composition and
nutritional value. The effects of “Aroeira” trees on the micro-climatic conditions were also evaluated. The experiment adopted
a randomized block design with five blocks (cutting seasons), two treatments (a shaded pasture—B. brizantha cv. Marandu shaded by M. urundeuva—and a pasture in full sun—B. brizantha cv. Marandu in full sun), and three replicates. The tree component, composed of the tree species M. urundeuva in the experimental density adopted, increased dry matter and crude protein of the forage mass harvest above stubble height,
without affecting the concentration of neutral detergent fibre or acid detergent fibre, thus causing dry matter and organic
matter in vitro degradability as well as effective degradability of the forage grass to remain the same as those obtained
in full sun. Therefore, the results of this study show the possibility of using trees and grass to increase both animal production
and environmental services. 相似文献
89.
Vicente Martins Gomes Ricardo Moreira Souza Silvaldo Felipe da Silveira Alexandre Macedo Almeida 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(2):393-401
In guava decline, Fusarium solani-immune guava trees become susceptible to extensive root rot caused by this fungus after parasitism by Meloidogyne enterolobii. To understand the mechanisms involved in this disease, root exudates were collected from nematode-inoculated (NI) or uninoculated (UN) guava plants cultivated in sand. After filtration through a Millipore® membrane, NI and UN exudates were used: i) to prepare media to assess their effect on mycelial growth and production of propagules of F. solani isolate UENF/CF 163, and ii) to incubate macro- and microconidia to assess their effect on germination. NI exudates promoted (P?<?0.05) more mycelial growth and production of propagules than UN exudates or water. NI and UN exudates were used to water guava seedlings laid over seed germination paper inside plastic boxes. Half of the seedlings had an agar plug colonized by the fungus positioned in the collar region. Upon watering with NI exudates the fungus caused (P?<?0.05) extensive rotting of the seedlings’ rootlets. NI and UN exudates, either unlyophilized or lyophilized and re-suspended to the original concentration, were used to water guava seedlings grown in sterile sand before being inoculated (or left uninoculated) as described before. Solely upon watering with NI exudates, in its unlyophilized form or after lyophilization, the fungus caused a reduction (P?<?0.05) of shoot and root biomass associated with rotting of roots. These results suggest that M. enterolobii induces chemical changes in the root exudates of guava trees, which are necessary for root invasion causing root rotting by F. solani. 相似文献
90.
Flávio Martins Santana Cesar Bauer Gomes Cesar Rombaldi Valmor João Bianchi Ailton Reis 《Phytoparasitica》2013,41(5):557-568
The populations of Phytophthora infestans (Pi) in southern Brazil in 2004 and 2005 are characterized herein. The isolates were collected from potato and tomato plants in the states of Paraná (PR), Santa Catarina (SC), and Rio Grande do Sul (RS). The mating type of 131 potato and 32 tomato isolates was determined. Forty-nine isolates from potatoes and 11 from tomatoes were analyzed for their Gpi phenotype. A subset of 35 isolates was evaluated for mitochondrial (mtDNA) polymorphisms. A sample of 146 isolates was tested for sensitivity to the fungicide metalaxyl, and most isolates (64%) were moderately sensitive. Fifty-nine isolates were classified as A1 mating type and 103 as A2. One isolate behaved as both A1 and A2 mating type. All tomato isolates were A1 mating type and presented the 86/100 pattern for the enzyme GPI and mtDNA Ib, indicating that these isolates belong to the US-1 clonal lineage. Of the 131 potato isolates, 103 were A2, 27 were A1 and one was A1/A2 mating type. Among the potato isolates 27 exhibited the Gpi phenotype 100/100, the same as BR-1, and 20 were 86/100, the same as US-1. Potato isolates presented the mitochondrial haplotypes Ia (74%) and IIa (26%). The data suggest the presence of only the BR-1 clonal lineage on potatoes in the states of PR and SC. However, in the state of RS, more than one clonal lineage was observed infecting potatoes, and there may be sexual reproduction between the lineages. 相似文献