• MAHMUDUL HAQUE
• Uttam Kumar Kanp
• Ram Kumar Bhakat
• Aloke Bhattacharjee

It was attempted to study the allelopathic potential of three profusely growing invasive weeds of West Bengal viz- Desmostachya bipinnata L. Stapf (Poaceae), Parthenium hysterophorus L. Asteraceae, Alternanthera sessilis L. R. Br. ex DC. (Amaranthaceae),, on the seeds of species Vigna radiata (Fabaceae) ,the chosen bioassay material in this case. These were analyzed by some specific germination behaviour indices of of Vigna radiata measured in terms of percentage of seed germination , T50 (time required for 50% germination ), TTC stainability of seeds and speed of seed germination exposed to various concentrations [1:5, 1:10 and 1:20 (w/v)] of leaf extracts of the weeds respectively. Obtained data reveal allelopathy as a dose and response phenomenon depending on the concentration of allelochemicals i.e. higher the concentration of extracts greater is the resistance to the percentage and speed of seed germination and seed respiratory activities as indicated by reduced stainability with TTC along with increase of the T50 values. Observed data and their coefficient of determination values indicate that the data is good fit and significant and also help to establish the relative allelopathic potential of the weeds as. Alternanthera < Parthenium < Desmostachya indicating that the monocotyledonous weed Desmostachya is more allelopathically vigorous than the other two dicotyledonous weeds Parthenium and Alternanthera. Further research might thus be relevant to know the interaction of other invasive dicotyledonous and monocotyledonous weeds on other weed and crop species opening new vistas of research.

Key words: Allelopathy, Alternanthera sessilis, Bioassay material, Desmostachya bipinnata, Germination behaviour, Parthenium hysterophorus, Vigna radiata, weeds.

"DETERMINATION OF RELATIVE ALLELOPATHIC VIGOUR OF THREE WEEDS OF WEST BENGAL USING THEIR LEAF EXTRACTS ON GERMINATION BEHAVIOUR OF VIGNA RADIATA SEEDS ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 12, page no.231-238, December-2018, Available :http://www.jetir.org/papers/JETIR1812432.pdf

"DETERMINATION OF RELATIVE ALLELOPATHIC VIGOUR OF THREE WEEDS OF WEST BENGAL USING THEIR LEAF EXTRACTS ON GERMINATION BEHAVIOUR OF VIGNA RADIATA SEEDS ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 12, page no. pp231-238, December-2018, Available at : http://www.jetir.org/papers/JETIR1812432.pdf