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

纳米比亚位于非洲西南部，是一个干旱的国家，有纳米布和卡拉哈里两个著名的沙漠。这项研究的目的是引入广泛的水稻种植，以与纳米比亚北部洪水生态系统Oshanas的水环境相协调。这种水稻种植应该有利于当地维持生计的农民，并与现有的珍珠谷子种植相协调，为纳米比亚人民提供稳定的食物。我们首先讨论了四年的研究方向，重点是珍珠谷子水分利用研究和水稻品种选择研究，以及纳米比亚洪涝田的胁迫环境研究。开花期，间作豌豆的SD值与湿地水相似，珍珠谷子的SD值远低于湿地水和地下水的SD值。这表明，在与豌豆争夺不同水源的水分时，间作珍珠谷子不能充分利用湿地水。奥沙纳湿地的水稻产量比泛滥平原高19%。在第二季的评估中，Oshana的总产量略有增加，但洪泛区的产量下降了20%，这可能是由于植物生长期间发生的洪水造成的过量水分的胁迫。结果表明，这两个地点都可以用于水稻生产，但由于盛行的阳光充足和干燥的环境，Oshanas比洪泛平原更适合种植水稻。在受盐渍影响的Oshana的雨季试验中，耐盐品种Pokkali的绝对产量和相对产量最高。总的来说，这些实验结果表明，Pokkali在雨季可以在受盐分影响的Oshanas下种植，尽管其生长持续时间较长。我们还引进了日本传统的水稻收割机，并同意继续为未来的纳米比亚进行水稻研究项目。

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.