PHYTOTOXIC EFFECTS OF SOME MEDICINAL PLANTS ON GERMINATION AND SEEDLING GROWTH OF SOME SELECTIVE PLANTS

Abstract

An experiment was conducted during the period of January-June, 2017 at the Agricultural Chemistry Laboratory and net house (field condition) to investigate the phytotoxic effects of ten medicinal plants (cirota, bohera, anantamul, nagesshor, ashok, arjun, bashok, akandho, darucini and rosundi) aqueous extract on germination and seedling growth efficiency of five selective plants, three dicot (cauliflower, broccoli and tomato) and two monocot (foxtail millet and barnyard grass) under both condition. The aqueous extracts of medicinal plants at six different concentrations (control, 0.001, 0.003, 0.01, 0.03 and 0.1 g/ml) were examined on five plant species in the laboratory condition and concentrations (control, 1, 2, 3, 4 and 5 g/ml) were examined only for bashok extract on five plant species in the net house (field condition). Result indicated that the germination efficiency, plumule length (cm) and radicle length (cm) and dry weight of plants were completely inhibited at the highest concentration of aqueous extracts (0.1g/ml) where at least inhibition was observed at control. There was a clearly observed variation of treatment effect between the monocot and dicot plants where monocot plants (foxtail millet and barnyard grass) showed great treatment effects than dicot plants (cauliflower, broccoli and tomato) and out of three dicot plants, the least variation of treatment effect was found in tomato because of its larger seed size and hard seed coat . Among the (leaf & flower) aqueous extract of ten medicinal plants, the treatment effect of cirota, bashok and rosundi caused the greatest variation in the germination percentages, plumule length, radicle

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length and dry weight of five selective plants but mostly in foxtail millet and barnyard grass. Thus, phototoxic effects of cirota, bashok and rosundi may reduce weed competition with crops by significantly affecting the germination and seedling growth of foxtail millet and barnyard grass.