Allelopathic effects of agroforestry tree species on seed germination and seedling growth of paddy varieties.

摘要

The allelophatic effect of the aqueous leaf extracts of three agroforestry tree species viz. Dalbergia sissoo, Acacia lenticularis and Bombax ceiba was examined on seed germination and seedling growth of three (Prabhat, Saket-4 and Kamini) popular rice (Oryza sativa) varieties. The study was conducted during kharif season of 2000 in the agroforestry laboratory, Department of Forestry, Rajendra Agricultural University, Pusa, Samastipur, Bihar, India. The aqueous leaf extracts reduced the seed germination and seedling growth of rice. On the basis of the value of percent reduction in seed germination and Germination Relative Index (GRI), the inhibitory effect of different leaf extracts was maximum in Kamini followed by Prabhat and Saket-4. The shoot and root dry weight, shoot length, root width and root number declined, whereas root and shoot ratio increased with the increase in the concentration of the leaf extracts of all the three tree species. Leaf extract of all three species showed inhibitory effect on sugar and protein and stimulatory effect on total amino acid contents of rice seedling. The results indicated that the allelopathic effect of leaf extracts of B. ceiba on different varieties of rice was maximum in terms of all physiological and biochemical parameters..