丘陵红壤区旱稻需水量试验的研究

Study on the Water Requirement of Upland Rice in Hilly Red-earth Areas

应用“坑测法”测定了旱稻需水量 ,结果表明 :中亚热带丘陵红壤地区旱稻需水量为 5 14 .0 mm。该需水量约为同期降雨量的 6 1% ,一般年景不用灌溉。过多过少水量都影响旱稻生长 ;低于 35 0 .0 mm不能成穗。旱稻根系发达 ,吸水吸肥和抗旱能力强 ,特别适宜丘陵地区种植。

Water requirements of upland rice was measured with non weighing lysimeters. Experimental results showed that optimum water requirement of upland rice in middle subtropical hilly red earth areas was about 514.0 mm, which is about 61% of precipitation in the same period. Therefore, irrigation is not necessary generally in growth season of upland rice in these areas. Too much or too less water supply, compared with the optimum water requirement value, may restrict obviously the growth and development of upland rice. Water supply of less than 350.0 mm may result in fail of heading. Experimental results also indicated that upland rice, with strong root system and high water uptake ability, is rather suitable to the hilly red earth area.