147 research outputs found

    Análise da estratégia de melhoramento do arroz ciclo curto em função dos estresses hídricos para Goiás.

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    Esse trabalho tem como objetivos: Determinar as variações geográficas e inter anual dos padrões de seca para a cultura de arroz ciclo curto em Goiás; Determinar o impacto dos estresses hídricos no rendimento da cultura em Goiás; Proporcionar estratégias que podem melhorar a eficiência do programa de melhorament

    Análise da estratégia de melhoramento do milho safra em função dos estresses hídricos para Goiás.

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    Esse trabalho tem como objetivos: Determinar as variações geográficas e inter-anual dos padrões de seca para a cultura de milho em Goiás; Determinar o impacto dos estresses hídricos no rendimento da cultura em Goiás; Proporcionar estratégias que podem melhorar a eficiência do programa de melhoramento em Goiás

    Past, present and future criteria to breed crops for water-limited environments in West Africa

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    Asia's Green Revolution of the 1960s and 1970s has largely bypassed West Africa, and "modern" (high-yielding, input responsive) germplasm for staple crops has found comparatively little adoption, except for systems that are have good access to markets and sufficient water resources. It is unlikely, however, that breeding objectives conserving traditional crop characteristics as found in extensive systems would have been more successful. The authors identify systems caught in the agricultural transition from subsistence to intensified, market-oriented production as the most important target for crop improvement, and provide examples of new breeding objectives for cowpea, sorghum and upland rice. In each of these cases, breeders, with the help of physiologists, have developed innovative plant-type concepts that combine improved yield potential and input responsiveness with specific traditional crop characteristics that remain essential during the agricultural transition. In the case of cowpea, dual-purpose varieties were developed that produce a good grain yield due to an erect plant habit, then produce new leaves enabling a second harvest of green foliage. For upland rice systems that are limited by labour (mainly needed to control weeds that abound due to shortened fallow periods), a weed competitive plant type was developed from Oryza sativa × Oryza glaberrima crosses. Lastly, sorghum breeders who had previously deselected photoperiod sensitivity are now re-inserting sensitivity into plants having "modern" architecture, in order to allow for flexible sowing dates while maintaining an agro-ecologically optimal time of flowering near the end of the wet season. The ecophysiological basis of these plant types, their place in current and future cropping systems, as well as the problem of under-funding for their realisation, are discussed

    Climate change and cereal production evolution trend in the Sahel: case study in Mali from 1951 to 2010

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    Open Access Journal; Published online: 9 April 2019Mali is a Sahelian country with a large climatic contrast from North to South. The current climatic and production evolutionary study is focused on the six major agro-climatic cereal production zones ranging from Kayes (400 mm) to Sikasso (>1000 mm) of rainfalls. Climatic data are rainfall records, daily maximum and minimum temperatures from 60 years of the six major synoptic weather observation stations. Data were analyzed on comparing average decades of the two normal periods of 30 years (1951-1980) and (1981-2010). Annual agronomic production data for millet, sorghum, maize and rice are derived from Mali's agricultural statistics base from 1984 to 2013. Main climatic results analyses indicate that climate change resulted in a decrease of 100 mm isohyets between the 2 periods of 30 years. The structure of the rainy season was little changed between these two periods since the average start of the season was delayed by 6 days and the average end date of the season became earlier by 4 days. Maximum temperatures increased significantly from + 0.44°C to + 1.53°C and minimum temperatures significantly increased from + 1.05°C to + 1.93°C in varying way depending on the sites. Statistics of major agronomic food crop production in Mali from 1984 to 2013 indicate an average increase of 985 to 4492 thousand tones, or 22% increase per year. There is a positive upward in saw tooth trend in Malian production from 1984 to 2013. This positive trend is the result of a combination of agricultural extension, agronomic research application and the management of small farmer holder in the Sahel. This evolution needs better study for drawing necessary right conclusions
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