Effects of aqueous extract of some herbal plant leaves on seed germination and seedling growth of bean (Lablab niger) and borboti (Vigna unguiculata)

Abstract

An experiment was conducted on aqueous extracts of leaves of some herbal plants viz., bohera (Terminalia belirica), horitoki (Terminalia chebula), tulsi (Ocimum gratissmum) and arjun (Terminalia arjuna) for investigating the presence of biologically active substance. The seeds of two vegetable crop such as, country bean (Lablab niger) and borboti (Vigna unguiculata), were testing for germination and seedling growth treating with aqueous extract of four herbal plant leaves. The chemical investigation on effective plant extract was also attempted. The aqueous extract of horitoki significantly reduced and delayed germination, growth of shoot length and root length of country bean, and borboti seeds compared with control whereas, bohera increased and enhanced germination, growth of shoot length and root length of these same vegetable crops. The maximum germination was in country bean, and borboti seeds within 4 and 3.77days respectively, treated with the leaves extract of bohera compared with control. Shoot lengths were 15.63 and 15.83 cm and root length were 8.44 and 8.65 cm for country bean, and borboti seedlings, respectively, due to the presence of growth regulator. The aqueous extract of horitoki showed the lowest and late germination at 5 and 4.77days and minimum shoot length were 12.01 and 12.76 cm, and root length were 5.56 and 5.82 cm for country bean, and borboti seedlings, respectively, due to the presence of growth inhibiting substances or toxic compounds. The growth promoting effect of bohera leaves extract on the tested vegetable crops seemed due might be the presence of biologically active substances. The thin layer chromatography (TLC) examination of chloroform extract of bohera leaves showed four distinct compounds at Hexane: Ethyl acetate (3:1, v/v) while horitoki leaves showed three distinct compounds at Hexane: Ethyl acetate (5:1, v/v).