Increased growth response of strawberry roots to a commercial extract from Durvillaea potatorum and Ascophyllum nodosum

Abstract

The withdrawal of soil fumigants like methyl bromide is forcing strawberry growers to consider supplementary and alternative ways of producing crops. In addition to controlling soil-borne pests, soil fumigation causes an increased growth response in strawberry roots, and the use of biostimulants may offer an alternative to replace this response. We tested the hypothesis that treatment with a commercial extract (Seasol®) from the seaweeds Duvillaea potatorum and Ascophyllum nodosum can increase root growth, and transplant (runner) and fruit yields of strawberry. From 2014 to 2016, we conducted three field trials on strawberry farms in the nursery sector at Toolangi and in the fruiting sector at Coldstream in Victoria, Australia. We applied the seaweed extract as a monthly drench (10 L ha−1) to two cultivars of strawberry (‘Albion’ and ‘Fortuna’), compared with an untreated control. In the nursery sector, use of the extract significantly increased the density of secondary roots (feeder roots) on harvested runners by up to 22%. Treatment with the extract also significantly increased yields of marketable runners by 8–19%. In the fruit sector, use of the extract significantly increased the root length density (root length per volume of soil) of strawberry plants by 38% and marketable fruit yields by 8%. Root length density at final harvest and marketable fruit yield of strawberry were highly correlated (r = 0.94). This relationship provides an insight into the mode of action of seaweed extracts and is discussed. Overall, the results show the potential benefits of the integrated use of seaweed extracts in strawberry production across the nursery and fruit sectors, and their promise for supplementing or replacing the increased growth response provided by soil fumigants.

The Potentiality of Marine Macro-Algae as Bio-Fertilizers to Improve the Productivity and Salt Stress Tolerance of Canola (Brassica napus L.) Plants

“…This indicated that seaweeds are efficient bio-fertilizers under normal growth conditions and noticeably increased their plant tolerance under stressful conditions. Khan et al [4] and Mattner et al [33] reported positive outcomes when seaweeds were used. These outcomes included root development, leaf quality, general plant vigor, and resistance to pathogens.…”

Trends in Seaweed Extract Based Biostimulants: Manufacturing Process and Beneficial Effect on Soil-Plant Systems

“…Different application rates of Kappaphycus alvarezii were investigated in respect to 100% of the recommended dose of fertilizers on maize [29] and potato tubers [30], interestingly, 7.5% was found to be the best application rate at both studies. Similarly, Mattner et al [31] applied a commercial seaweed extract based on Duvillaea potatorum and Ascophyllum nodosum on strawberry at nursery and production stages, results showed an increase of the root length density of plants which had been treated at the production stage regardless of whether the treatment was applied at the nursery stage or not. This increase was highly correlated with the enhancement of the final yield recorded.…”

Phaeophyceaean (Brown Algal) Extracts Activate Plant Defense Systems in Arabidopsis thaliana Challenged With Phytophthora cinnamomi

“…The seaweeds used in this study are different, so the extracts are not identical, therefore we standardized the testing approach. The 1:400 dilution of the extracts were chosen because of (i) greenhouse and field studies demonstrating the efficacy for this dilution ( Mattner et al, 2013 , 2018 ), and (ii) by testing for root growth efficacy using the dilution as described previously ( Arioli et al, 2015 ). For alignment with our previous greenhouse and field studies and the root growth testing, each of the seaweed extracts where standardized to 16% (w/w) soluble solids before preparing the 1 in 400 dilution for each seaweed extract.…”

“…This study used the model plant A. thaliana and the generalist, globally devastating pathogen P. cinnamomi, to examine the impacts of treatment of plants with two selected brown algal extract-based biostimulants or their combination, on pathogen growth and development in roots. Several previous studies have shown that applications of various brown algal extracts, either to soil or to foliage, enhanced root growth and plant development (Arioli et al, 2015;Mattner et al, 2018). Here we have used a sand culture system to grow A. thaliana with extracts from A. nodosum ("AN"), or D. potatorum ("DP"), or their combination ("AN/DP").…”