Research Note on viability of herbicide and Hormone - treated seeds of four tropical weed species

Abstract

The responses and viability of acid scarified seeds of four tropical weeds to gibberellic acid and seven herbicides including Galex, Gramoxone, 2 - 4 D, Atrazine, Simazine, Roundup and Primextra in the Laboratory were investigated. The weeds used are Cassia occidentalis, Cassia obtusifolia Cassia hirtusa and Calapogonium mucunoides. A concentration of 100 ppm solutions of the herbicides inhibited germination of seeds in the 4 weed species. Only 50 ppm 2-4D, Atraxine and Primextra inhibited seed germination in C. occidentalis. Solutions of 100 ppm Galex and Atrazine reduced the viability of seeds of C. hirtusa to 0%. The Germination rate was increased by 100 ppm gibberellic acid. Total percentage seed germination in herbicide-free seeds ranged between 75 - 90%.

Keywords: Weeds, seed germination, herbicides gibberellic acid

Tanzania J. Agric. Sc. (2000) Vol. 3 No.1, 81-86