Physicochemical analyses of plant biostimulant formulations and characterisation of commercial products by instrumental techniques
Six commercially used seaweed extracts were tested for cytokinin- and auxin-like activity using the soybean callus bioassay and the mung bean rooting bioassay respectively. All the seaweed extracts tested showed cytokinin-like activity. Seamac caused the most callus growth with activity being concentrated at R f 0.9 which co-chromatographed withiso-pentenyladenine and its riboside. The other five seaweed extracts yielded activity at R f 0.7–0.8. This co-chromatographed with zeatin and zeatin riboside. All the seaweed extracts tested improved rooting of mung beans. Kelpak made fromEcklonia maxima (Osbeck) Papenf. gave the best rooting response.