The germination and growth of choi-sum (Brassica rapa var. parachinensis) after siam weed (Chromolaena odorata) extract treatment

Abstract

Damayanti N, Anggarwulan E, Sugiyarto. 2013. The germination and growth of choi-sum (Brassica rapa var. parachinensis) after siam weed (Chromolaena odorata) extract treatment. Biofarmasi 11: 58-68. Siam weed (Chromolaena odorata (L.) R.M. King & H. Rob.) has allelophatic agent potential. Allelochemical is released by siam weed possibly affect the seed germination and growth of choi-sum (Brassica rapa L. var. parachinensis L.H. Bailey). The aim of this research was to study the effect of siam weed extract on the seed germination and growth of choi-sum. This research used a completely randomized design (CDR) with two factors and three replications. The first factor was extract source, i.e. (i) leaf extract, (ii) stem extract and (iii) mixed extract. The second factor was extract concentration with five levels, i.e. 0% as control, 25%, 50%, 75% and 100%. The variables that measured including germination percentage, time to germination, height of plant, root length, leaf wide total, sum of leaves, fresh weight, dry weight, root-shoot ratio, chlorophyll and carotenoid content. The collected data were analyzed by analisis of varians and followed by Duncan Multiple Range Test with 5% of confidence level. The results showed that siam weed extract was not significantly affect the percentage germination but significantly affect the time to germination of choi-sum, whereas seeds began to germinate some of which on the second day and all the seeds germinated on the fifth day. The higher concentrations significantly affected the plant height and increased the root-shoot ratio, but it tended to lower the tested plant leaf area.