旱作水稻根系在不同土層吸水量的品種間差異（預報）

Abstract

水稻的栽培，原以灌溉方便的水田為限。在缺水地區以普通方法栽培水稻時，因未能充份灌溉，即不能適應。但以水稻的旱地栽培方法，則可改善不少。因此為便於將來擒這種栽培方法，首先對於旱作水稻的吸水特性宜加研究，然後針對其吸水特性調節灌溉方法，以提高產量，使缺水地區栽培水稻的困難得以解除。 The study was conducted at Taiwan Agricultural Research Institute to determine the irrigation method for lowland rice varieties that cultivated on upland. The three-layer-type auto-irrigators which can measure the amount of water absorbed by rice roots and the development of root system in different soil layers, were used in this study. The soil was divided into three layers of 0-20, 20-40 and 40-60 cm in depth. The soil moisture of very layer was controlled at the level of 75-80% of soil-water-holding-capacity. Nine hills of lowland rice for each of the three varieties in each crop season, wereplanted by direct seeding method on each auto-irrigator in the greenhouse These auto-irrigators were covered with vinyl film so as to stop the water evaporation from their surfaces. The windows of the greenhouse were opened but covered by screens; and several air ventilators were used during day time to minimize the room tempera-ture.