Seedling growth of selected field crop species as influenced by Jatropha curcas extract

Purpose: The experiment was conducted to investigate into the allelopathic potential of the aqueous extracts of different parts of Jatropha curcus on seven selected field crop species. Research method: The leaf, stem, bark, twig, root, pericarp, seed and oilcake extracts of J. curcus at four different concentrations (1:5, 1:10, 1:15 and 1:20 (w/v)) were tested against jute, mungbean, mustard, radish, rice, wheat and tomato. Control i.e. distilled water without extracts was also maintained in each case. The experiments were conducted following completely randomized design with three replications. Findings: Except few, the aqueous extracts of J. curcas plant parts significantly inhibited the seedling growth of all the test species at concentration more than 1:15 (w/v) whereas, at or below this level stimulated the seedling growth. Percent shoot and root growth inhibition of the test crops varied among J. curcus parts extract from 10 to 100, at 1:5 (w/v) concentration. At the same concentration, J. curcas oilcake extract completely (100%) inhibited the shoot and root growth of all the test crop species except rice. Similarly, seed extract completely inhibited (100%) the shoot and root growth of jute and mustard, whereas around or more than 70% inhibition of the shoot and root growth of all the test species except rice. These results confirm that J. curcus has allelopathic properties and may possess allelochemicals. Since oilcake of J. curcus extract had greater inhibitory activity than other parts, this could be used for isolation and identification of allelochemical(s). The results of this experiment will be helpful for the researchers to know the plantplant interaction of J. curcus with its neighboring plant species or the intercrops introduce in Jatropha field. Limitations: There was no significant limitation to the report. Originality/Value: This research compares the allelopathic properties of different parts of Jatropha curcus on seven selected field crop species.