Three peanut (Arachis hypogaea) varieties were maintained at soil water levels ranging from moderately wet to very dry. Pod yield and quality were significantly reduced in treatments receiving less than about 30 cm of water during the growing season. Although not statistically different, yield and quality tended to increase as irrigation amounts increased from 40 to about 60 cm. Average harvestable yields for 4 years were 4464, 5080 and 4543 kg/ha for Florigiant, Florunner and Tifspan, respectively, when irrigated to a profile depth of 60 cm when the soil moisture tension in the surface 30 cm reached 0.2 bar. This compares with yields of 2631, 3341 and 3125 kg/ha for Florigiant, Florunner and Tifspan, respectively, when the soil water tension in the surface 30 cm profile was allowed to reach 15.0 bars. Water extraction to a depth of 106 cm was recorded for all three varieties. Apparent plant use of water from profile depths greater than 60 cm was observed at about 75 days after planting. Evapotranspiration vs age relationships were developed from daily soil water measurements to a 1.2 m soil depth.

Yellow nutsedge (Cyperus esculentus L.) is a serious weed problem in the United States and other countries. An indigenous rust fungus [Puccinia canaliculata (Schw.) Lagerh.], pathogenic on yellow nutsedge, was released in early spring as a potential biological control agent. The fungus inhibited nutsedge flowering and new tuber formation. The fungus also dehydrated and killed nutsedge plants. The successful control of yellow nutsedge by a rust epiphytotic under experimental conditions demonstrates the potential use of the rust in an integrated weed management system.

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