Preliminary observations on the influence of certain weeds on germination and growth of Pennisetum typhoideum rich.

The paper deals with four weeds ( Digera muricata, Indigofera cordifolia, Trichodesma amplexicaule and Tribulus terrestris) growing on the fields in which Bajra ( Pennisetum typhoideum) is cultivated. Studies have been undertaken on the interaction of these weeds on the germination of seeds and seedling growth of Pennisetum typhoideum. The aqueous extracts from these weeds did not prove harmful as far as germination was concerned, although delay in certain cases was evident. The inhibition as well as enhancement of seedling growth was exhibited by extracts of these weeds. The best effect of growth enhancement was indicated by I. cordifolia and T. amplexicaule and that of inhibition by D. muricata and T. terrestris. Comparatively greater toxicity was caused to the first root, but the development of adventitious roots compensated for the retarding effect. Root hair formation was suppressed in the portion which remained in contact with extract, otherwise profuse root hair formation took place in other areas. [ABSTRACT FROM AUTHOR]