I am working with three other scientists from Missouri (MU and USDA-ARS) testing center pivot irrigated rice in Limpopo Province, South Africa. The objective is to grow rice in Africa with less water than conventional flood irrigation. Nerica 4, 11, and 14 rice seed was purchased for the experiment from AfricaRice Center in Benin. Seeds were treated with fungicides and insecticide (Celest/Regent/Icon) before planting on November 2. An irrigation study (frequency and amount) is being conducted on 36 acres under a South Africa Zimmatic center pivot. A variable rate system was installed on the system which allows us to program application treatments on a large scale with three replications.
Alternating low rate applications of Command and Prowl were applied early in the season for residual grass and broad leaf control. The study is being conducted in a field which was planted in Roundup Ready corn in 2009. Unfortunately, the previous farmer did a poor job of harvesting the grain and volunteer corn is the most problem weed in the rice. In mid-December, Clincher herbicide was sprayed to control the corn. Most of the corn is dying and we will be spraying 2,4-D this week to kill wild watermelon and Wandering Jew (Tradescantia fluminersis) weeds.
This week, I have been working on completing the wiring and setup of a Campbell Scientific weather station. This weather data (temperature, wind, radiation, and humidity) will be used to calculate daily soil and plant evapotranspiration (ET). This will be used to determine the amount of irrigation water to apply in the study. In another part of the field under the same pivot, we are conducting a small variety test with seven rice cultivars from Brazil, Cambodia, and West Africa.
South Africa has very distinct wet and dry seasons. When I visited the farm in early August it was dry and cool. January is mid-summer here. In the Limpopo Province this is the rainy season. It has rained every day this week. Usually lightning has accompanied the rain and caused electric power and internet interruptions.