Impact of AMPEP on the growth and occurrence of epiphytic Neosiphonia infestation on two varieties of commercially cultivated Kappaphycus alvarezii grown at different depths in the Philippines

Abstract

Two varieties of the carrageenophyte Kappaphycus alvarezii (Tungawan, TUNG; and Giant tambalang, GTAM) from Zamboanga Sibugay, Philippines were used to test the efficacy of Acadian Marine Plant Extract Powder (AMPEP) as source of nutrients for growth, and to determine if applications had any effect on the percent occurrence of an epiphytic infestation of the red alga Neosiphonia sp. at four different depths in the sea. Results showed that the use of AMPEP significantly (P<0.05) increased the growth rate of both Kappaphycus varieties tested but decreased the percent occurrence of Neosiphonia sp. The percent occurrence of Neosiphonia sp. infection (6-50% at all depths) of both Kappaphycus varieties with AMPEP treatment was significantly lower than the controls (i.e., 10-75% at all depths). Both the growth rate of the cultivated seaweed and the percent occurrence of the epiphytes decreased as the cultivation depth increased. Plants dipped in AMPEP and suspended at the surface had the highest growth rates (i.e., 4.1%, TUNG; 3.1%, GTAM) after 45 days; those without AMPEP dipping had the highest percent occurrence of Neosiphonia infection (viz. 70-75%). The occurrence of Neosiphonia infestation was found to be correlated with changes in irradiance and salinity at the depths observed. The results suggested that both varieties of K. alvarezii used in this study have the fastest growth rate when grown immediately at the water surface. However, in order to minimize damage caused by the occurrence of epiphytic Neosiphonia, K. alvarezii should be grown within a depth range of 50-100 cm. These observations are important for the improved management of Kappaphycus for commercial farming. Furthermore, the use of AMPEP treatments for enhancement of growth and reduction deleterious Neosiphonia sp. infections is encouraging.

Extract powder from the brown alga Ascophyllum nodosum (Linnaeus) Le Jolis (AMPEP): a “vaccine-like” effect on Kappaphycus alvarezii (Doty) Doty ex P.C. Silva

“…The efficiency of the use of AMPEP improving the K. alvarezii daily growth rate and preventing the settling of epiphytes was demonstrated by Hurtado et al (2009), Loureiro et al (2010, Borlongan et al (2011). Similar results were also achieved with all the treatments where AMPEP was used in this work (KA and KAE) when compared to oxidative burst induced ones (KAO and KAOE).…”

“…These compounds would be part of a pathway leading to an oxidative burst eliciting the production of hydrogen peroxide and promoting the bleaching of the epiphytic thalli, as observed by Pedersén et al (1996a, b) for other genera and by Weinberger et al (1999) for Gracilaria conferta (Schousboe ex Montagne) Montagne. This may provide some explanation for the non-settling and survival of epiphyte propagules as described in previous works (Borlongan et al 2011). It also might explain the bleaching effect caused by the oxidative burst in K. alvarezii induced samples and the bleaching effect on P. subtilissima as well as K. alvarezii low daily growth rate and higher carrageenan yield when compared to other samples not induced to produce an oxidative burst response.…”

“…Silva cultures, showed promising results on improving plantlets in tissue culture, increasing daily growth rates and mitigating the occurrence of epiphytes (Hurtado et al 2009;Loureiro et al 2010;Yunque et al 2011;Borlongan et al 2011). However, the mechanisms of action of the AMPEP extract have not yet been discussed or tested.…”

Epiphytic and Ice-ice Diseases of Seaweed, <i>Kappaphycus alvarezii</i> and its Effect on Growth Rate and Carrageenan Quality

“…The results of the research in the field observations indicate that the prevalence of epiphytes can reach 70-75%. It is in accordance with Borlongan et al (2011). The research indicates that also ice-ice decreases the production of seaweed from 25-40%.…”

Intimate Associations Between Epiphytes, Endophytes, and Parasites of Seaweeds

“…However, type III to type V epiphytes (see above), as well as endophytes and eukaryotic parasites, cannot be controlled by such treatments and alternative methods based on the current understanding of the genetic and biochemical basis of close associations are required in order to limit their impacts on algal mariculture. Interestingly, a recent study showed that dipping of seedlings in a commercial extract from Ascophyllum nodosum (AMPEP), prior to out-planting, was efficient for both improving the daily growth rate and increased productivity of both varieties of Kappaphycus and could be used as part of a management protocol to control or reduce the impact of Neosiphonia infection in commercial cultivation areas in the sea (Borlongan et al 2011).…”