The growth effect of a seaweed extract made from Ecklonia maxima on germinating Avocado and Pecan seed

Abstract

Abstract The traditional commercial propagation of both avocado (Persea americana) and pecan (Carya illinoinensis) trees is initiated from a single seed. The uniform germination of strong seedlings has a direct impact on the success of future grafting operations. The use of drench treatments of Afrikelp™ LG 1, a biostimulant extracted from the South African kelp Ecklonia maxima, on germinating avocado (Edranol) and pecan (Ukalinga) seed, was evaluated for any growth benefits at this initial stage of propagation. Both the avocado and pecan seed were pretreated according to industry standards and placed in a germination room with a set temperature of 30 ̊C. On germination (radicle emergence), seeds were sown into 1L Elle growbags containing composted pine bark augmented with 3 g L− 1 Multicote™ 4 and placed into a temperature-controlled tunnel. Four different concentrations of Afrikelp™ LG 1 (0.5, 1.0, 2.0 and 4.0%) together with a control treatment (water), were applied as 250 mL drench applications every two weeks, with a total of four applications. Two weeks after the final drench application, the plants were destructively harvested, and final growth measurements were recorded. Foliar samples from each treatment were sent for nutrient analysis (macro- and micro-nutrients). All Afrikelp™ LG 1 treated plants showed increases in vegetative growth (foliar and dry root biomass, height; root collar diameter) and chlorophyll content, with 0.5 and 1.0% Afrikelp™ LG 1 (avocado) and 1.0 and 2.0% (pecan) treatments consistently outperforming the water control.