Introduction of Extensive Rice Cultivation Hamlonized with Pearl Millet Farming in an Flooding Ecosystem in Arid Country of Namibia

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Namibia, situated in south west Africa, is an arid county with two famous desert of Namib and Kalahari. The aim of this research is to introduce extensive rice cultivation which will harmonize with the water environment in the flooding ecosystem, oshanas, in northern Namibia. This rice cultivation should be beneficial for the local subsistence fanners, and harmonize with the existing pearl millet farming, stable food for Namibian people. We, first discussed the direction of four years research, and focused on pearl millet water use research and rice cultivar selection study, and stress environment study in Namibian flooding fields. At flowering time, the SD value of intercropped cowpea was similar to that of wetland water, while that in pearl millet was much lower than those of both the wetland water and groundwater. This indicated that intercropped pearl millet did not have full access to the wetland water when there was competition with cowpea for water derived from various water sources. Paddy yield was 19% higher in the wetland, oshana than in the floodplain. In the second season of evaluation, there was a slight increase in overall yield in the oshana, but the yield in the floodplain reduced by 20%, possibly, because of stress by excessive water as result of the flood that occurred during plant growth. The results indicated that both locations can be used for rice production ; but oshanas are more suitable than floodplains because of the prevailing sunny and dry environment. In the wet season experiment under a saline-affected oshana, a salt tolerant genotype Pokkali produced the highest absolute and relative paddy yield. Generally, the results of these experiments indicated that Pokkali may be cultivated under saline-affected oshanas during the wet season, although its growth duration is relatively long. We have also introduced Japanese traditional rice post harvesting machines, and agreed to continue the rice research project for future Namibia.