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1.
J Environ Manage ; 354: 120285, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368800

RESUMO

In the world there are approximately 608 million farms, of which 84% are small farms and produce 35% of the food of the world population. Training programs have been promoted by different organizations to achieve a more sustainable and efficient agricultural practice. Within this context, this article has classified a set of smallholders located in central Nicaragua with regard to how they apply Land Use Management Initiatives (LUMI). The aim is to outline their weaknesses and strengths and thus identify key elements that can contribute to improving soil resource management. We focus on the LUMI carried out in Nicaragua in the municipalities of El Tuma-La Dalia, El Cuá and Waslala between 1992 and 2022. To conduct this study, eight LUMI were identified and analysed, and 25 indicators linked to the Malawi Principles were extracted and selected for the design of a survey in order to collect land use management information from 455 farms in the study area. Simple random sampling was used to select the farms. Subsequently, the collected data were analysed using descriptive statistics and Multivariate Analysis techniques. The results reveal that in the study area, the LUMI incorporate between one and five Malawi Principles. The multivariate analysis techniques employed identified three clusters of farms, with either Active, Moderate or Improvable ecosystem management. The study area as a whole displays strengths in social participation, local capacity building, soil and environmental conservation practices, with the farm as the main source of income. Weaknesses lie in the fact that indicators referring to household income and productivity are less frequent. In terms of farm management, the results revealed that combined male and female management was similar in percentage to male-only management. The results highlight the need to continue with the implementation of environmental goals linked to the design of initiatives that promote productivity, income and gender equity in farm management in an integrated manner. At the same time, existing local capacities for sustainable soil and ecosystem management should be brought together and strengthened.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Nicarágua , Produtos Agrícolas , Agricultura/métodos , Fazendas , Solo
2.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469373

RESUMO

Abstract Among Bemisia tabaci species, the invasive MEAM1 and MED species are key agricultural pests for many crops. In Brazil, most part of B. tabaci population outbreaks were associated with MEAM1, which, since 1990s quickly spread across the entire country. Later in 2014, the MED was identified in Brazil, initially more restricted to greenhouses, but suddenly reaching new areas in the South and Southeast open regions. Thus, our objective was to investigate the geographical distribution of MEAM1 and MED on open field crops in Brazil. MEAM1 is still the predominant species on open field crops such as soybean, cotton, and tomato. The sequencing of a cytochrome c oxidase subunit I (COI) gene fragment revealed a single haplotype of MEAM1, suggesting the establishment of a single MEAM1 strain in the country. The haplotypes found for MEAM1 and MED are genetically related to the globally dispersed strains, Jap1 and Mch1, respectively. Continuous monitoring of B. tabaci species is crucial because landscape alterations, climatic changes, and pest management methods may shift the B. tabaci species distribution and dominance in Brazilian crop areas.


Resumo Dentre as espécies de Bemisia tabaci, as espécies invasoras MEAM1 e MED se destacam como pragas de grande importância para várias culturas. No Brasil, a maior parte dos surtos populacionais de mosca-branca são associados a presença da espécie MEAM1, que a partir 1990 se espalhou por todo o país. Por outro lado, em 2014 a espécie MED foi identificada no Brasil, inicialmente restrita a casas de vegetação, mas rapidamente se difundindo em novas áreas nas regiões Sul e Sudeste do Brasil. Assim, nosso objetivo foi investigar a distribuição geográfica das espécies MEAM1 e MED em grandes culturas no Brasil. A espécie MEAM1 continua sendo predominante nas monoculturas como algodão, soja e tomate. O sequenciamento de um fragmento do gene citocromo c oxidase subunidade I (COI) revelou a presença de um haplótipo para MEAM1, sugerindo o estabelecimento de apenas uma linhagem no país. Os haplótipos encontrados para MEAM1 e MED são geneticamente relacionados as linhagens globalmente dispersas Jap1 e Mch1, respectivamente. O monitoramento contínuo das espécies de B. tabaci é crucial pois as mudanças na paisagem, mudanças climáticas e métodos de manejo das pragas podem alterar a dominância e a distribuição dessas espécies nas áreas agrícolas do Brasil.

3.
Braz. j. biol ; 84: e256949, 2024. tab, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360214

RESUMO

Among Bemisia tabaci species, the invasive MEAM1 and MED species are key agricultural pests for many crops. In Brazil, most part of B. tabaci population outbreaks were associated with MEAM1, which, since 1990s quickly spread across the entire country. Later in 2014, the MED was identified in Brazil, initially more restricted to greenhouses, but suddenly reaching new areas in the South and Southeast open regions. Thus, our objective was to investigate the geographical distribution of MEAM1 and MED on open field crops in Brazil. MEAM1 is still the predominant species on open field crops such as soybean, cotton, and tomato. The sequencing of a cytochrome c oxidase subunit I (COI) gene fragment revealed a single haplotype of MEAM1, suggesting the establishment of a single MEAM1 strain in the country. The haplotypes found for MEAM1 and MED are genetically related to the globally dispersed strains, Jap1 and Mch1, respectively. Continuous monitoring of B. tabaci species is crucial because landscape alterations, climatic changes, and pest management methods may shift the B. tabaci species distribution and dominance in Brazilian crop areas.


Dentre as espécies de Bemisia tabaci, as espécies invasoras MEAM1 e MED se destacam como pragas de grande importância para várias culturas. No Brasil, a maior parte dos surtos populacionais de mosca-branca são associados a presença da espécie MEAM1, que a partir 1990 se espalhou por todo o país. Por outro lado, em 2014 a espécie MED foi identificada no Brasil, inicialmente restrita a casas de vegetação, mas rapidamente se difundindo em novas áreas nas regiões Sul e Sudeste do Brasil. Assim, nosso objetivo foi investigar a distribuição geográfica das espécies MEAM1 e MED em grandes culturas no Brasil. A espécie MEAM1 continua sendo predominante nas monoculturas como algodão, soja e tomate. O sequenciamento de um fragmento do gene citocromo c oxidase subunidade I (COI) revelou a presença de um haplótipo para MEAM1, sugerindo o estabelecimento de apenas uma linhagem no país. Os haplótipos encontrados para MEAM1 e MED são geneticamente relacionados as linhagens globalmente dispersas Jap1 e Mch1, respectivamente. O monitoramento contínuo das espécies de B. tabaci é crucial pois as mudanças na paisagem, mudanças climáticas e métodos de manejo das pragas podem alterar a dominância e a distribuição dessas espécies nas áreas agrícolas do Brasil.


Assuntos
Animais , Controle de Pragas , Mapeamento Cromossômico , Pragas da Agricultura
4.
Plants (Basel) ; 12(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37687273

RESUMO

This study aimed to investigate the role of Se supply in improving osmotic stress tolerance in coffee seedlings while also evaluating the best timing for Se application. Five times of Se foliar application were assessed during induced osmotic stress with PEG-6000 using the day of imposing stress as a default, plus two control treatments: with osmotic stress and without Se, and without osmotic stress and Se. Results demonstrated that osmotic stress (OS) promoted mild stress in the coffee plants (ψw from -1.5MPa to -2.5 MPa). Control plants under stress showed seven and five times lower activity of the enzymes GR and SOD compared with the non-stressed ones, and OS was found to further induce starch degradation, which was potentialized by the Se foliar supply. The seedlings that received foliar Se application 8 days before the stress exhibited higher CAT, APX, and SOD than the absolute control (-OS-Se)-771.1%, 356.3%, and 266.5% higher, respectively. In conclusion, previous Se foliar spray is more effective than the Se supply after OS to overcome the adverse condition. On the other hand, the post-stress application seems to impose extra stress on the plants, leading them to reduce their water potential.

5.
Front Genome Ed ; 5: 1181811, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457887

RESUMO

The security of Earth's food systems is challenged by shifting regional climates. While agricultural processes are disrupted by climate change, they also play a large role in contributing to destabilizing greenhouse gases. Finding new strategies to increase yields while decreasing agricultural environmental impacts is essential. Tropical agriculture is particularly susceptible to climate change: local, smallholder farming, which provides a majority of the food supply, is high risk and has limited adaptation capacity. Rapid, inexpensive, intuitive solutions are needed, like the implementation of genetically modified (GM) crops. In the Latin American tropics, high awareness and acceptance of GM technologies, opportunities to test GM crops as part of local agricultural educations, and their known economic benefits, support their use. However, this is not all that is needed for the future of GM technologies in these areas: GM implementation must also consider environmental and social sustainability, which can be unique to a locality. Primarily from the perspective of its educators, the potential of a rural Colombian university in driving GM implementation is explored, including the role of this type of university in producing agricultural engineers who can innovate with GM to meet regionally-dependent environmental and cultural needs that could increase their sustainability.

6.
Front Plant Sci ; 13: 1000430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172560

RESUMO

The effects of selenium (Se) on plant metabolism have been reported in several studies triggering plant tolerance to abiotic stresses, yet, the effects of Se on coffee plants under chilling stress are unclear. This study aimed to evaluate the effects of foliar Se application on coffee seedlings submitted to chilling stress and subsequent plant recovery. Two Coffea species, Coffea arabica cv. Arara, and Coffea canephora clone 31, were submitted to foliar application of sodium selenate solution (0.4 mg plant-1) or a control foliar solution, then on day 2 plants were submitted to low temperature (10°C day/4°C night) for 2 days. After that, the temperature was restored to optimal (25°C day/20°C night) for 2 days. Leaf samples were collected three times (before, during, and after the chilling stress) to perform analyses. After the chilling stress, visual leaf injury was observed in both species; however, the damage was twofold higher in C. canephora. The lower effect of cold on C. arabica was correlated to the increase in ascorbate peroxidase and higher content of starch, sucrose, and total soluble sugars compared with C. canephora, as well as a reduction in reducing sugars and proline content during the stress and rewarming. Se increased the nitrogen and sulfur content before stress but reduced their content during low temperature. The reduced content of nitrogen and sulfur during stress indicates that they were remobilized to stem and roots. Se supply reduced the damage in C. canephora leaves by 24% compared with the control. However, there was no evidence of the Se effects on antioxidant enzymatic pathways or ROS activity during stress as previously reported in the literature. Se increased the content of catalase during the rewarming. Se foliar supply also increased starch, amino acids, and proline, which may have reduced symptom expression in C. canephora in response to low temperature. In conclusion, Se foliar application can be used as a strategy to improve coffee tolerance under low-temperature changing nutrient remobilization, carbohydrate metabolism, and catalase activity in response to rewarming stress, but C. arabica and C. canephora respond differently to chilling stress and Se supply.

7.
Data Brief ; 40: 107837, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35242900

RESUMO

For several decades, maize (Zea mays L.) management decisions in smallholder farming in tropical regions have been a puzzle. To best balance alternative management practices' environmental and economic outcomes, an extensive dataset was gathered through CIMMYT's knowledge hub in Chiapas, a state in southern Mexico. In a knowledge hub, farmers, with the support of farm advisors, compare conventional and improved agronomic practices side-by-side and install demonstration fields where they implement improved practices. In all these fields data on on-farm operations and results is collected. The dataset was assembled using field variables (yield, cultivars, fertilization and tillage practice), as well as environment variables from soil mapping (slope, elevation, soil texture, pH and organic matter concentration) and gridded weather datasets (precipitation, temperature, radiation and evapotranspiration). The dataset contains observations from 4585 fields and comprises a period of 7 years between 2012 and 2018. This dataset will facilitate analytical approaches to represent spatial and temporal variability of alternative crop management decisions based on observational data and explain model-generated predictions for maize in Chiapas, Mexico. In addition, this data can serve as an example for similar efforts in Big Data in Agriculture.

8.
Plants (Basel) ; 10(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209953

RESUMO

Sustainable management strategies are needed to improve agronomic efficiency and cereal yield production under harsh abiotic climatic conditions such as in tropical Savannah. Under these environments, field-grown crops are usually exposed to drought and high temperature conditions. Silicon (Si) application could be a useful and sustainable strategy to enhance agronomic N use efficiency, leading to better cereal development. This study was developed to explore the effect of Si application as a soil amendment source (Ca and Mg silicate) associated with N levels applied in a side-dressing (control, low, medium and high N levels) on maize and wheat development, N uptake, agronomic efficiency and grain yield. The field experiments were carried out during four cropping seasons, using two soil amendment sources (Ca and Mg silicate and dolomitic limestone) and four N levels (0, 50, 100 and 200 kg N ha-1). The following evaluations were performed in maize and wheat crops: the shoots and roots biomass, total N, N-NO3-, N-NH4+ and Si accumulation in the shoots, roots and grain tissue, leaf chlorophyll index, grain yield and agronomic efficiency. The silicon amendment application enhanced leaf chlorophyll index, agronomic efficiency and N-uptake in maize and wheat plants, benefiting shoots and roots development and leading to a higher grain yield (an increase of 5.2 and 7.6%, respectively). It would be possible to reduce N fertilization in maize from 185-180 to 100 kg N ha-1 while maintaining similar grain yield with Si application. Additionally, Si application would reduce N fertilization in wheat from 195-200 to 100 kg N ha-1. Silicon application could be a key technology for improving plant-soil N-management, especially in Si accumulator crops, leading to a more sustainable cereal production under tropical conditions.

9.
Data Brief ; 33: 106553, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33294535

RESUMO

Remote sensing allows obtaining information on agriculture regularly with non-invasive measurement approaches. Field data is crucial for adequate agricultural monitoring by remote sensing. However, public available field data are scarce, mainly in tropical regions, where agriculture is highly dynamic. The present publication aims to support the reduction of this gap. The LEM+ dataset provides information monthly about 16 land use classes for 1854 fields from October 2019 to September 2020 (one Brazilian agricultural year) from Luís Eduardo Magalhães (LEM) and other municipalities in the west of Bahia state, Brazil. The reference data were collected in two fieldworks (March 2020 - first crop season, and August 2020 - second crop season). The boundaries of the fields visited in situ were delimited using Sentinel-2 false color compositions (near infrared - red - green) at 10 m spatial resolution. The land use classes were labeled monthly based on information collected in situ (agricultural land use and photographs) and by visual interpretation of Sentinel-2 false color composition (near infrared - shortwave infrared - red) and MODIS/Terra (Normalized Difference Vegetation Index) time series. The dataset can be useful for the development of new pattern recognition methods for agricultural land use mapping and monitoring, comparison of different classification methods, and optical and SAR remote sensing time series analysis. This dataset contributes to complement previous initiatives [1], [2] to make tropical agriculture field reference data publicly available.

10.
Methods Mol Biol ; 2061: 131-139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31583657

RESUMO

To develop plants that are more tolerant to drought, marginal soil fertility, and diseases and that satisfy demands for high yield, new cultivars of the tropical fruit papaya (Carica papaya L.) are needed. Nonetheless, in many cases, these traits are available in only wild relatives found throughout Latin America. Understanding meiotic progression may facilitate the introgression of desirable traits into commercial cultivars that maintain high fertility. In this protocol, we describe a practical and simple method to effectively isolate male meiocytes in order to document the behavior of papaya meiotic chromosomes.


Assuntos
Carica/genética , Análise Citogenética , Meiose/genética , Cromossomos de Plantas , Análise Citogenética/métodos , Hibridização In Situ
11.
Rev. Ciênc. Agrovet. (Online) ; 19(1): 54-63, 2020. tab
Artigo em Português | VETINDEX | ID: biblio-1488385

RESUMO

Restrições na disponibilidade hídrica favorecem eventuais danos à cultura do feijoeiro, e o uso de biorreguladores aprimora a sinalização vegetal e potencializa a indução de tolerância ao déficit hídrico. Este estudo objetivou caracterizar alterações fisiológicas, bioquímicas e biométricas em plantas de feijão submetidas à aplicação foliar de biorreguladores sob diferentes regimes hídricos. O ensaio consistiu na aplicação de um controle (água) e três biorreguladores (5 µM de ácido abscísico - ABA; 50 µM de metil jasmonato - MeJA e 5 µM de ABA + 50 µM de MeJA), além de apresentar dois regimes hídricos (60 e 80% da capacidade de campo), num esquema fatorial 4 x 2. Foram analisados: conteúdo de pigmentos fotossintetizantes, trocas gasosas foliares e índices biométricos das plantas de feijoeiro. Com resultado observou-se que o tratamento ABA+MeJA incrementou a concentração de clorofila b, atividades de ascorbato peroxidase (APX) e catalase (CAT), enquanto a taxa fotossintética foi estimulada pela mistura de biorreguladores aos 36 dias após o plantio (DAP), ABA e MeJA, isolados, propiciaram maior taxa fotossintética no feijoeiro aos 34 DAP, enquanto para as variáveis biométricas somente foram influenciadas pelos regimes hídricos, com relação aos mecanismos bioquímicos, constatou-se que o tratamento ABA+MeJA incrementou a atividade das enzimas antioxidantes e melhorou as respostas...


Restrictions on water available lead to possible damages in the bean crop, and the use of bioregulators can improve the plant signal and boost tolerance against drought stress. This study aimed to characterize physiological, biochemical, and biometric alterations in bean plants subjected to foliar application of bioregulators under different soil water levels. The following treatments were applied: control (water) and three bioregulators (5 M of abscisic acid - ABA, 50 M of methyl jasmonate MeJA, and 5 M of ABA + 50 M of MeJA). Also, the plants were subjected to two soil water levels (60 and 80% of field capacity), in a 4 x 2 factorial scheme. The variables studied were: content of photosynthetic pigments, leaf gas exchange, and biometric indexes in the common bean plants. Our results showed that the ABA + MeJA treatment increased the concentration of chlorophyll b, ascorbate peroxidase (APX), and catalase (CAT) activities. At the same time, the photosynthetic rate was stimulated by the mixture of bioregulators on 36 days of planting (DAP). ABA and MeJA, applied isolated, caused a higher photosynthetic rate in the bean in the 34 DAP, whereas for the biometric variables, they were only influenced by the soil water levels. Regarding the biochemical mechanisms, it was verified that the ABA + MeJA treatment increased the activity of antioxidant enzymes and improved gas...


Assuntos
Desidratação , Phaseolus/crescimento & desenvolvimento , Phaseolus/efeitos dos fármacos , Reguladores de Crescimento de Plantas
12.
R. Ci. agrovet. ; 19(1): 54-63, 2020. tab
Artigo em Português | VETINDEX | ID: vti-28875

RESUMO

Restrições na disponibilidade hídrica favorecem eventuais danos à cultura do feijoeiro, e o uso de biorreguladores aprimora a sinalização vegetal e potencializa a indução de tolerância ao déficit hídrico. Este estudo objetivou caracterizar alterações fisiológicas, bioquímicas e biométricas em plantas de feijão submetidas à aplicação foliar de biorreguladores sob diferentes regimes hídricos. O ensaio consistiu na aplicação de um controle (água) e três biorreguladores (5 µM de ácido abscísico - ABA; 50 µM de metil jasmonato - MeJA e 5 µM de ABA + 50 µM de MeJA), além de apresentar dois regimes hídricos (60 e 80% da capacidade de campo), num esquema fatorial 4 x 2. Foram analisados: conteúdo de pigmentos fotossintetizantes, trocas gasosas foliares e índices biométricos das plantas de feijoeiro. Com resultado observou-se que o tratamento ABA+MeJA incrementou a concentração de clorofila b, atividades de ascorbato peroxidase (APX) e catalase (CAT), enquanto a taxa fotossintética foi estimulada pela mistura de biorreguladores aos 36 dias após o plantio (DAP), ABA e MeJA, isolados, propiciaram maior taxa fotossintética no feijoeiro aos 34 DAP, enquanto para as variáveis biométricas somente foram influenciadas pelos regimes hídricos, com relação aos mecanismos bioquímicos, constatou-se que o tratamento ABA+MeJA incrementou a atividade das enzimas antioxidantes e melhorou as respostas...(AU)


Restrictions on water available lead to possible damages in the bean crop, and the use of bioregulators can improve the plant signal and boost tolerance against drought stress. This study aimed to characterize physiological, biochemical, and biometric alterations in bean plants subjected to foliar application of bioregulators under different soil water levels. The following treatments were applied: control (water) and three bioregulators (5 M of abscisic acid - ABA, 50 M of methyl jasmonate MeJA, and 5 M of ABA + 50 M of MeJA). Also, the plants were subjected to two soil water levels (60 and 80% of field capacity), in a 4 x 2 factorial scheme. The variables studied were: content of photosynthetic pigments, leaf gas exchange, and biometric indexes in the common bean plants. Our results showed that the ABA + MeJA treatment increased the concentration of chlorophyll b, ascorbate peroxidase (APX), and catalase (CAT) activities. At the same time, the photosynthetic rate was stimulated by the mixture of bioregulators on 36 days of planting (DAP). ABA and MeJA, applied isolated, caused a higher photosynthetic rate in the bean in the 34 DAP, whereas for the biometric variables, they were only influenced by the soil water levels. Regarding the biochemical mechanisms, it was verified that the ABA + MeJA treatment increased the activity of antioxidant enzymes and improved gas...(AU)


Assuntos
Reguladores de Crescimento de Plantas , Phaseolus/efeitos dos fármacos , Phaseolus/crescimento & desenvolvimento , Desidratação
13.
Environ Pollut ; 249: 949-958, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30965547

RESUMO

Usage of neonicotinoids is common in all agricultural regions of the world but data on environmental contamination in tropical regions is scarce. We conducted a survey of five neonicotinoids in soil, water and sediment samples along gradients from crops fields to protected lowland tropical forest, mangroves and wetlands in northern Belize, a region of high biodiversity value. Neonicotinoid frequency of detection and concentrations were highest in soil (68%) and lowest in water (12%). Imidacloprid was the most common residue reaching a maximum of 17.1 ng/g in soil samples. Concentrations in soils differed among crop types, being highest in melon fields and lowest in banana and sugarcane fields. Residues in soil declined with distance to the planted fields, with clothianidin being detected at 100 m and imidacloprid at more than 10 km from the nearest applied field. About half (47%) of the sediments collected contained residues of at least one compound up to 10 km from the source. Total neonicotinoid concentrations in sediments (range 0.014-0.348 ng/g d. w.) were about 10 times lower than in soils from the fields, with imidacloprid being the highest (0.175 ng/g). A probabilistic risk assessment of the residues in the aquatic environment indicates that 31% of sediment samples pose a risk to invertebrate aquatic and benthic organisms by chronic exposure, whereas less than 5% of sediment samples may incur a risk by acute exposure. Current residue levels in water samples do not appear to pose risks to the aquatic fauna. Fugacity modeling of the four main compounds detected suggest that most of the dissipation from the agricultural fields occurs via runoff and leaching through the porous soils of this region. We call for better monitoring of pesticide contamination and invertebrate inventories and finding alternatives to the use of neonicotinoids in agriculture.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Sedimentos Geológicos/química , Neonicotinoides/análise , Praguicidas/análise , Solo/química , Água/química , Animais , Belize , Medição de Risco , Inquéritos e Questionários , Áreas Alagadas
14.
Front Plant Sci ; 10: 74, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30891046

RESUMO

Plant breeding is directly linked to the development of crops that can effectively adapt to challenging conditions such as soil nutrient depletion, water pollution, drought, and anthropogenic climate change. These conditions are extremely relevant in developing countries already burdened with population growth and unchecked urban expansion, especially in the tropical global southern hemisphere. Engineering new crops thus has potential to enhance food security, prevent hunger, and spur sustainable agricultural growth. A major tool for the improvement of plant varieties in this context could be the manipulation of homologous recombination and genome haploidization during meiosis. The isolation or the design of mutations in key meiotic genes may facilitate DNA recombination and transmission of important genes quickly and efficiently. Genome haploidization through centromeric histone mutants could be an option to create new crosses rapidly. This review covers technical approaches to engineer key meiotic genes in tropical crops as a blueprint for future work and examples of tropical crops in which such strategies could be applied are given.

15.
Sci. agric ; 71(5): 420-429, Set-Out. 2014. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497431

RESUMO

The use of Biological Control methods is on the increase, mainly as a result of the mobilization of human resources in entomology studies since the establishment of graduate programs in this country in the 1960s. This review approaches the retrospective of Biological Control in Brazil in recent decades, with an emphasis on the "culture of applying agrochemicals" adopted by Brazilian growers, which constrains progress in this area. Successful cases of Biological Control have been reported on in Brazil and there are, in fact, excellent programs in place that use insects or entomopathogenic microrganisms for insect pest control. Most of the studies in this area have been published in Portuguese and are, therefore, not readily available internationally. Importantly, half of the planted sugarcane (Saccharum officinarum), around four million hectares, is treated with natural enemies (insects) and/or pathogens. In contrast to other countries that employ Biological Control in small areas, the challenge in Brazil is to implement programs in large farms. Many obstacles must be overcome and discussed in working groups so that we can assume a world leadership position in the use of Biological Control in tropical regions as Brazil is already considered the leader in tropical agriculture. In this review, use of Biological Control is discussed within the Integrated Pest Management philosophy, as a path toward sustainable agriculture that is in harmony with other pest control methods. We must develop a technology of Biological Control adapted to tropical regions, rather than copying models developed for temperate regions, which are usually inappropriate for Brazilian conditions.


Assuntos
Agricultura Sustentável/métodos , Controle Biológico de Vetores/história , Controle Biológico de Vetores/métodos , Brasil , Zona Tropical
16.
Sci. Agric. ; 71(5): 420-429, Set-Out. 2014. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-27308

RESUMO

The use of Biological Control methods is on the increase, mainly as a result of the mobilization of human resources in entomology studies since the establishment of graduate programs in this country in the 1960s. This review approaches the retrospective of Biological Control in Brazil in recent decades, with an emphasis on the "culture of applying agrochemicals" adopted by Brazilian growers, which constrains progress in this area. Successful cases of Biological Control have been reported on in Brazil and there are, in fact, excellent programs in place that use insects or entomopathogenic microrganisms for insect pest control. Most of the studies in this area have been published in Portuguese and are, therefore, not readily available internationally. Importantly, half of the planted sugarcane (Saccharum officinarum), around four million hectares, is treated with natural enemies (insects) and/or pathogens. In contrast to other countries that employ Biological Control in small areas, the challenge in Brazil is to implement programs in large farms. Many obstacles must be overcome and discussed in working groups so that we can assume a world leadership position in the use of Biological Control in tropical regions as Brazil is already considered the leader in tropical agriculture. In this review, use of Biological Control is discussed within the Integrated Pest Management philosophy, as a path toward sustainable agriculture that is in harmony with other pest control methods. We must develop a technology of Biological Control adapted to tropical regions, rather than copying models developed for temperate regions, which are usually inappropriate for Brazilian conditions.(AU)


Assuntos
Controle Biológico de Vetores/história , Controle Biológico de Vetores/métodos , Agricultura Sustentável/métodos , Brasil , Zona Tropical
17.
Zookeys ; (407): 1-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24899828

RESUMO

The genus Mononychellus is represented by 28 herbivorous mites. Some of them are notorious pests of cassava (Manihot esculenta Crantz), a primary food crop in the tropics. With the exception of Mononychellus tanajoa (Bondar), their geographic distribution is not widely known. This article therefore reports observational and specimen-based occurrence data of Mononychellus species associated with cassava. The dataset consists of 1,513 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT's Arthropod Reference Collection (CIATARC). Most of the records are from the genus' native range in South America and were documented between 1980 and 2000. Approximately 61% of the records belong to M. tanajoa, 25% to M. caribbeanae (McGregor), 10% to M. mcgregori (Flechtmann and Baker) and 2% to M. planki (McGregor). The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF).

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