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1.
Glob Food Sec ; 33: 100628, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35784265

RESUMO

Rice production has increased significantly with the efforts of international research centers and national governments in the past five decades. Nonetheless, productivity improvement still needs to accelerate in the coming years to feed the growing population that depends on rice for calories and nutrients. This challenge is compounded by the increasing scarcity of natural resources such as water and farmland. This article reviews 17 ex-post impact assessment studies published from 2016 to 2021 on rice varieties, agronomic practices, institutional arrangements, information and communication technologies, and post-harvest technologies used by rice farmers. From the review of these selected studies, we found that stress-tolerant varieties in Asia and Africa significantly increased rice yield and income. Additionally, institutional innovations, training, and natural resource management practices, such as direct-seeded rice, rodent control, and iron-toxicity removal, have had a considerable positive effect on smallholder rice farmers' economic well-being (income and rice yield). Additional positive impacts are expected from the important uptake of stress-tolerant varieties documented in several Asian, Latin American, and African countries.

2.
Plant Mol Biol ; 109(3): 215-232, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33630231

RESUMO

KEY MESSAGE: A molecular analysis using informative SNP markers in 1570 clones of cassava from Vietnam reveals varietal composition from farmers' field and genebank collections Cassava is the most important smallholder cash crops in Southeast Asia and is especially used in industrial products. Yet, systematic genetic studies on molecular markers from Vietnamese germplasm have not been considered for breeding and conservation programs. We conducted a molecular analysis of 1570 clones of cassava germplasm from farms across six agro-ecological zones using informative SNP markers. We unraveled the genetic diversity and population structure and provided insights into the value of breeding and conservation programs. Duplicated genotypes comprised 98% of the total sample of the Central Highlands region. Ninety-six SNPs were amplified Central Highlands and South East provinces had the highest allelic richness, covering up to 83% of alleles. The average observed heterozygosity (Ho = 0.43) was slightly higher than expected (He = 0.40) across SNP markers, suggesting an excess of heterozygotes plants. Diversity indexes indicated that cassava populations from North West and Eastern Vietnam are genetically diverse (mean He = 0.40). Genetic parentage tests identified 85 unique genetic groups within the varieties KM94, KM419, BRA1305, KM101, KM140, PER262, KM60, KM57 and two unidentified varieties, which accounted for 82% of the frequency distribution. KM94 is the most dominant variety in Vietnamese farms surveyed (38%), reflecting its superior quality and productivity. Discriminant analysis of principal components (DAPC) revealed four main subgroups, which were partially corroborated by neighbor joining (NJ) analyses. After removing duplicates, 31 unique genotypes were distributed across five of the agro-ecological zones. These were well distributed in the subgroups revealed via DAPC and NJ analyses. The genetic groups identified herein could be used to select unique accessions that should ideally conform with ex situ germplasm collections and identify areas where on-farm conservation programs should be targeted. Newly identified genotypes may also contribute as genetic breeding resources that could be used to adapt cassava to future changes and farmers' needs.


Assuntos
Impressões Digitais de DNA , Manihot , Melhoramento Vegetal , Manihot/genética , Vietnã
4.
Nat Plants ; 6(10): 1242-1249, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33051615

RESUMO

Livestock support the livelihoods of one billion people in Africa, Asia and Latin America, but the productivity of animals remains low, reducing the potential of the sector to support higher incomes and better nutrition. Improved livestock feeding has been identified as the most important step towards higher productivity. This scoping review assessed the evidence for the uptake of improved ruminant livestock feed options, the effect of this uptake on livestock productivity and the degree to which this improves smallholder farmer livelihoods. In total, 22,981 papers were identified, of which 73 papers were included in the final analysis after a rigorous double-blind screening review. Only papers that reported farmers' decision to use a new feed intervention were selected, thereby excluding feeding trials and participatory feed assessments. Of the 73 papers, only 6 reported combined evidence of adoption, effect on productivity and livelihood changes. A total of 58 papers looked at adoption, 19 at productivity change and 22 at livelihood change. This scoping review highlights the gap in evidence for the adoption of new livestock feeding practices and provides recommendations to support farmers' uptake of feed interventions.


Assuntos
Agricultura/economia , Ração Animal , Fazendeiros , Gado , Animais , Humanos , Ocupações/economia
5.
Breed Sci ; 70(2): 145-166, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32523397

RESUMO

In Asia, cassava (Manihot esculenta) is cultivated by more than 8 million farmers, driving the rural economy of many countries. The International Center for Tropical Agriculture (CIAT), in partnership with national agricultural research institutes (NARIs), instigated breeding and agronomic research in Asia, 1983. The breeding program has successfully released high-yielding cultivars resulting in an average yield increase from 13.0 t ha-1 in 1996 to 21.3 t ha-1 in 2016, with significant economic benefits. Following the success in increasing yields, cassava breeding has turned its focus to higher-value traits, such as waxy cassava, to reach new market niches. More recently, building resistance to invasive pests and diseases has become a top priority due to the emergent threat of cassava mosaic disease (CMD). The agronomic research involves driving profitability with advanced technologies focusing on better agronomic management practices thereby maintaining sustainable production systems. Remote sensing technologies are being tested for trait discovery and large-scale field evaluation of cassava. In summary, cassava breeding in Asia is driven by a combination of food and market demand with technological innovations to increase the productivity. Further, exploration in the potential of data-driven agriculture is needed to empower researchers and producers for sustainable advancement.

6.
PLoS One ; 13(8): e0201803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30089159

RESUMO

It is widely recognized that increasing agricultural production to the levels needed to feed an expanding world population requires sharply increased public investment in research and development and widespread adoption of new technologies, but funding for national and international agricultural research has rather declined in recent years. In this situation, priority setting has become increasingly important for allocating scarce research resources among competing needs to achieve greater impacts. Using partial equilibrium economic surplus models and poverty impact simulations, this paper assesses cassava research priorities in Africa, Latin America and Caribbean, and Asia based on the potential economic and poverty reduction impacts of alternative research and technology options. The results showed that efficient planting material production and distribution systems and sustainable crop and soil fertility management practices have the greatest expected economic and poverty reduction impacts in the three regions. Lack of clean planting materials is a major constraint to adoption and it is envisaged that efficient production and distribution systems for planting material can accelerate technology adoption by farmers. Similarly, sustainable crop and soil fertility management practices play a key role in closing the observed yield gaps, especially in Africa. The paper discusses the results of the priority assessment for key cassava research options and concludes with the implications for cassava research priorities.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Manihot , Pobreza/prevenção & controle , Projetos de Pesquisa , Pesquisa , África , Agricultura/economia , Ásia , Simulação por Computador , Conservação dos Recursos Naturais , Análise Custo-Benefício , Produtos Agrícolas/economia , Humanos , América Latina , Manihot/economia , Modelos Econométricos , Pesquisa/economia , Alocação de Recursos
7.
Data Brief ; 18: 1252-1256, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29900301

RESUMO

This article provides a description of an agricultural household survey data of rice growers collected in Ecuador between October 2014 and March 2015. The household survey was implemented using a structured questionnaire administered among 1028 households in the main rice production areas of Ecuador (i.e. Guayas, Los Rios, Manabi, and El Oro provinces). Information collected was provided by household heads (male or female) and included household and plot level data. The survey information includes household socio-demographic characteristics (e.g. age, education, gender, main economic activity, etc.), farm characteristics (e.g. farm land size, assets ownership, other crops planted, etc.), rice management practices (e.g. variety and input use, production costs, etc.), and rice production and utilization (e.g. yields, prices, sales, etc.). Additional socio-economic context variables were also recorded such as government subsidies to rice production, participation in rural organizations, and food security related questions. The dataset contains a total of 6288 variables among numeric, categorical and string variables. The dataset is shared publicly on the Harvard dataverse site and provide access to questionnaires, the complete data and a brief report.

8.
Acta amaz ; 37(2): 177-186, jun. 2007. graf, tab
Artigo em Espanhol | LILACS | ID: lil-462045

RESUMO

La riqueza de los suelos aluviales a lo largo de los ríos amazónicos permite altos rendimientos en los cultivos. En el Perú, esta característica ha sido sustento de propuestas que sugieren concentrar la agricultura amazónica en sus riberas. Sin embargo, la viabilidad económica de la agricultura ribereña sigue siendo desconocida. Este artículo usa un modelo agroeconómico y analiza la rentabilidad de la agricultura ribereña del río Ucayali en las cercanías de Pucallpa. Se da énfasis a la importancia de las distintas condiciones agronómicas y del mercadeo propias de la zona. Los resultados muestran que la rentabilidad de los sistemas agrícolas ribereños difiere con el tipo de tierra utilizado y con el carácter temporal o permanente de la actividad que realizan los agricultores. Además, la rentabilidad está condicionada a las variaciones propias de la agricultura ribereña, particularmente las inundaciones tempranas. Así los buenos rendimientos de sus suelos aluviales no garantizan la rentabilidad en todos sus cultivos y sistemas.


A fertilidade dos solos aluviais ao longo dos rios da Amazônia resulta em altos rendimentos agrícolas. No Peru, esta característica tem levado à propostas de política que sugerem que se concentre a agricultura da Amazônia ao longo das costas dos rios. Contudo, a viabilidade econômica da agricultura ribeirinha é ainda desconhecida. O presente artigo usa um modelo agroeconômico para analisar a lucratividade deste tipo de agricultura no rio Ucayalinas proximidades de Pucallpa. Enfase especial foi dada às condições de produção e comercialização na área. Os resultados mostram que a lucratividade dos sistemas de cultivo ribeirinhos variam de acordo com o tipo de solo em questão e a natureza temporal ou permanente das atividades dos agricultores. Ademais, esta lucratividade é condicionada pelas variações na agricultura ribeirinha, especialmente as enchentes prematuras dos rios. Deste modo, os bons rendimentos dos solos aluviais não garantem lucratividade para todas as culturas e sistemas de cultivo.


Assuntos
Ecossistema Amazônico , Agricultura
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