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Phosphorus is a key nutrient element involved in energy transfer for cellular metabolism, respiration and photosynthesis and its supply at low levels can affect legume nodulation, N fixation, and C assimilation. A two-year field study was conducted in Ethiopia in 2012 and 2013 to evaluate the effects of P supply on growth, symbiotic N nutrition, grain yield and water-use efficiency of three groundnut genotypes. Supplying P to the genotypes significantly increased their shoot biomass, symbiotic performance, grain yield, and C accumulation. There was, however, no effect on shoot δ C values in either year. Compared to the zero-P control, supplying 40 kg·ha P markedly increased shoot biomass by 77% and 66% in 2012 and 2013, respectively. In both years, groundnut grain yields were much higher at 20 and 30 kg·ha P. Phosphorus supply markedly reduced shoot δ N values and increased the %Ndfa and amount of N-fixed, indicating the direct involvement of P in promoting N fixation in nodulated groundnut. The three genotypes differed significantly in δ N, %Ndfa, N-fixed, grain yield, C concentration, and δ C. The phosphorus × genotype interaction was also significant for shoot DM, N content, N-fixed and soil N uptake.

Africa has experienced increasing aridity and higher frequency of droughts due to climate change during the half past century with possible adverse effects on agricultural production, especially in dry areas with low rainfall. Under the auspices of the Africa Water Action Program between the Chinese Ministry of Science and Technology (MOST) and the United Nations Environment Program (UNEP), the Institute of Agricultural Environment and Resources, Shanxi Academy of Agricultural Sciences (SAAS-IAER) has worked closely with domestic and overseas partners on technology transfer in Morocco, Zambia, Egypt, Niger and Ethiopia from 2008 to 2013. A drought early warning system has been established and validated, and drought adaptation technologies have been trialed, modified, demonstrated and extended in African countries, and this shows great potential to increase crop production, water and fertilizer use efficiency and desert control in rainfed areas of Africa. The project has continued for six years and is a successful case of technology transfer and capacity building in Africa. The knowledge and experience gained will be useful to researchers, technicians, aid agencies and policy makers who work on agricultural technology transfer for in dry areas of Africa.

Irrigation consumes three quarters of global water withdrawals each year. Strategies are needed to reduce irrigation water use, including increasing the efficiency of transfer methods and field application. Comprehensive restoration of soil health, specifically through organic matter amendments, can substantially reduce irrigation demand and increase crop yield. A program to restore severely degraded and desertified soils by incorporating coarse woodchips into the soil successfully increased rainfall capture and elevated soil moisture for several weeks between rainfall events at both Ningxia, north-west China and North Dakota, USA. With addition of fertilizer, woodchip incorporation further increased growth of wheat and alfalfa. Comprehensive soil health assessment of remnant grasslands was used to develop target reference soil profiles by which to guide restoration efforts. Given that most agricultural soils are degraded to some degree, soil health restoration can provide a powerful strategy toward achieving global food and water security.


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