美国路易斯安那州甘薯生产区的年平均降水量为1300—1450毫米。假如这些降水在全年中能够均匀分布,它将为该州大多数作物提供足够的水分。但实际分布经常是很不稳定的。在一定程度上由于甘薯具有庞大的根系及植株生长低矮,一般认为它属于中等抗旱作物。甘薯可在较长期干旱条件下存活并遇适当降雨后 The annual average precipitation in the Louisiana sweet potato producing area is 1300-1450 mm. If these rainfalls are distributed evenly throughout the year, it will provide enough water for most of the state’s crops. However, the actual distribution is often very unstable. To a certain extent, it is generally considered to be a moderate drought-resistant crop because of its large root system and its low plant growth. Sweet potatoes can survive longer-term drought conditions and encounter moderate rainfall