Résultats de la recherche | Land Portal

Résultats de la recherche

Showing items 1 through 9 of 572.
  1. Library Resource
    Articles et Livres
    décembre, 1982

    Chemical analysis and missing element trials with Sorghum vulgare L. showed that three Panamanian soils, representative of three great soil groups, were deficient in both nitrogen (N) and phosphorus (P). When a greenhouse trial was undertaken to test the response of Cajanus cajan to rhizobial inoculation, N and P fertilization in these soils, no response was obtained in either the Río Hato or Los Santos soils. There was a definite response to P and a slight response to inoculation in the Pacora soil, which had the poorest fertility level. N applications depressed nodulation.

  2. Library Resource
    Articles et Livres
    décembre, 1982

    Biological nitrogen (N2) fixation in both free-living and symbiotic organisms is an energy-requiring process dependent upon a supply of carbon and energy. In this paper the energy costs for N2 fixation and nodule respiration in symbiotic systems are compared with those of free-living N2-fixing systems, with the theoretical energy requierement for N2 fixation, and with the cost of utilization of combined N.

  3. Library Resource
    Articles et Livres
    décembre, 1985
    Colombie, Amérique centrale, Amérique du Sud

    The factors influencing the size and shape of exptl. field plots (area of exptl. lot, soil types, trial objective, no. of replicates, and degree of accuracy and homogeneity of the exptl. material) for the execution of field expt. are discussed. The basic principles of the following different methods to determine plot size are described: max. curve method, method of Koch and Rigney, Hatheway's method, and the max. curve method using the multiple linear regression model. Some considerations are presented on the border effect and on plot size in bush and climbing bean trials.

  4. Library Resource
    Articles et Livres
    décembre, 1987
    Indonésie, Asie, Asia du sud-est

    This analysis of global and Asian markets looks at protectionism and substitution (decline in starch trade, rise in trade of cassava feedstuffs) and the Asian regional market for cassava feedstuffs. The degree of substitution between cassava and grains has increased measurably during the postwar period. Cassava's future in world markets depends on its ability to compete with grains; so far this has depended on grain pricing policies and tariff structures of importing countries, making cassava trade more vulnerable than the international grain trade.

  5. Library Resource
    Rapports et recherches
    décembre, 2017
    Kenya, Nigéria, Ouganda, Burundi, Madagascar, Zimbabwe, République-Unie de Tanzanie, Soudan, Ghana, Éthiopie, Malawi, Afrique sub-saharienne, Afrique, Afrique orientale

    Our goal is to provide the scientific basis for development investments and policies that promote more productive, profitable agriculture, and healthier diets at no environmental cost. Low-income, smallholder farmers face significant challenges across sub-Saharan Africa (SSA). High population growth is coinciding with migration to the cities as younger populations seek out higher income-earning opportunities. Inadequate infrastructure and few markets for agricultural production in rural areas, for example, are leading to stagnated opportunities for smallholders.

  6. Library Resource
    Rapports et recherches
    décembre, 2017
    Kenya, Afrique orientale, Afrique

    The International Center for Tropical Agriculture (CIAT), in collaboration with our national research partners, has been working in Africa for the last 30 years. Our cutting-edge science helps policy makers, private sector, scientists, civil society, and farmers respond to the most pressing challenges of our time.

Rechercher dans la bibliothèque foncière

Grâce à notre moteur de recherche robuste, vous pouvez rechercher n'importe quel document parmi les plus de 64 800 ressources hautement conservées dans la bibliothèque du foncier.

Si vous souhaitez avoir un aperçu de ce qui est possible, n'hésitez pas à consulter le guide de recherche.

 

Partagez cette page