Abstract

                                The nut grass (Cyperus rotundus L.) is a formidable weed in the tro pics and sub-tropics. Results of experiments on its control have been reported by Ranade and Burns, 1925 (India), Smith and Fick, 1937 (America), and Andrews, 1940 (Egypt). The morphology of the plant as described by these workers is in general as follows: The weed possesses an elaborate underground system consisting of tubers, rhizomes and roots. Rhizomes connect the tubers with each other and from the latter are deve. loped extensive roots. The tubers are white and succulent when young but turn reddish brown and finally black with age. They consist of congested nodes and internodes with buds and scale-leaves at the nodes. The rhizo- mes proceeding upwards from some of the tubers produce the aerial parts of the plant consisting of rosettes of linear leaves and with the umbel-bear- ing scapes arising from the centre of the rosettes. At the junction of the leaves with the upward-growing rhizome is an enlargement resembling a tuber which has been termed a "basal bulb" by Ranade and Burns (1. c). Like the tuber, the basal bulb contains storage material and is capable of producing rhizomes from buds at its nodes.

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