Allelopathic potential of Inga laurina leaf extract on lettuce seed germination

Abstract

The aim of this study was to evaluate the allelopathic potential of Inga laurina leaves on the germination and growth of Lactuca sativa L. seedlings. The extract was obtained by blending 50 g of leaves in 500 ml of distilled water. Extracts were obtained by diluting the leaf homogenate in water to concentrations of 0 (control), 25, 50, 75 and 100%. The bioassay was conducted in a completely randomized design with five treatments and four repetitions of 50 seeds of L. sativa. The characteristics observed were germination and abnormal seedlings, germination rate, shoot length and root length, dry weight of seedlings and allelopathy index. There was no difference between extracts for germination ranging from 98%to 100%. The speed of germination rate and seedling root length decreased with increasing concentration and could be explained by second degree polynomial regression models with R² above 98%. The fresh mass increased with higher concentrations of the extract. The allelopathic index was negative, indicating inhibition, and increased with increasing extract concentration. The leaf extract of Inga laurina at different concentrations did not affect lettuce seed germination. Allelopathic potential was seen in the developmental characteristics of lettuce seedlings.