Optimization of culture conditions for tissue culture production of young plantlets of carrageenophyte Kappaphycus

Abstract

To improve the production of Kappaphycus plantlets in tissue culture, optimum media concentrations of an Ascophyllum nodosum extract (Acadian Marine Plant Extract Powder, AMPEP), plant growth regulators (PGR), pHtemperature combinations, and explant density were determined. Kappaphycus alvarezii var. tambalang purple (PUR), kapilaran brown (KAP), vanguard brown (VAN), adik-adik (AA), tungawan green (TGR), and K. striatum var. sacol green (GS) were used as explants. Based on the shortest period for shoot emergence and the economical use of AMPEP, the optimum enriched media was 3.0 mg L −1 AMPEP and 0.1 mg L −1 AMPEP+PGR 1 mg L −1 each phenylacetic acid (PAA) and zeatin for PUR, 1.0 mg L −1 AMPEP+PGR for KAP and GS, 0.1 mg L −1 AMPEP+PGR for VAN, and 3.0 mg L −1 AMPEP and 0.001 mg L −1 AMPEP+PGR for AA and TGR. Results showed that the addition of PGR to low concentrations of AMPEP hastened shoot formation. pH-temperature combinations for the most rapid shoot formation were determined for the brown (KAP) and purple (PUR) color morphotypes of K. alvarezii var. tambalang and the green morphotype of K. striatum var.sacol (GS) cultured in 1.0 mg L −1 AMPEP+PGR. The brown morphotype produced the most number of shoots at pH 7.7 at 20°C after as little as 20 days. Purple K. alvarezii showed an increased shoot formation at pH 6.7 at 25°C and the green K. striatum morphotype at pH 8.7 at 25°C. The optimum number of explants added to the culture media was also determined for tungawan green (TGR), brown (KAP), and tambalang purple (PUR) varieties of K. alvarezii in 1.0 mg L −1 AMPEP+PGR. The number of explants and the volume of the culture media combination were also tested. The highest average number of shoots formed occurred in two explants:1 mL culture media (2:1) for KAP and PUR (35.00% and 16.67%, respectively) and 1 explant: 2 mL culture media for the TGR (100.00%) with a range of 0.5-3.0 mm shoot length after 40 days in culture. The earliest shoot formation was observed after 21 days for the brown and 9 days for both the green and purple color morphotypes of Kappaphycus, in all densities investigated. This indicated that within the range tested, the density of explants did not have a significant effect on the rate of shoot formation but did influence the average number generated from the culture. The rate of production of new and improved Kappaphycus explants for a commercial nursery stock was improved through the use of AMPEP with optimized culture media pH, temperature, and density conditions.

Phyconomy: the extensive cultivation of seaweeds, their sustainability and economic value, with particular reference to important lessons to be learned and transferred from the practice of eucheumatoid farming

“…Earlier studies reported propagule production from spores (Azanza-Corrales & Aliaza 1999; Azanza-Corrales & Bulboa et al 2007Bulboa et al , 2008 Hurtado et al 2009;Luhan & Mateo 2017;Neves et al 2015;Reddy et al 2003;Sulistiani et al 2012;Tibubos et al 2017;Yeong et al 2014;Yong et al 2014Yong et al , 2015Yunque et al 2011;Zitta et al 2013). Because of the technical sophistication required, these were neither embraced by farmers nor, perhaps surprising, sponsored by the very industry which was dependent on generation of the raw materials for processing.…”

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

“…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.…”

Genetic Identification and Mass Propagation of Economically Important Seaweeds

“…Low growth rate of K. alvarezii explants in acidic conditions may also due to the denaturation of proteins beyond the tolerance limit, which in turn hinders the cellular physiological and biological processes of seaweeds [15]. However, better growth of purple K. alvarezii morphotype in slightly acidic condition (pH 6.7) was reported indicating different Kappaphycus varieties may respond differently to pH conditions [104].…”

“…The use of AMPEP was first reported to successfully induce the regeneration of young plants from different varieties of Kappaphycus seaweed [100]. Other studies have also highlighted the positive influence of AMPEP application on the growth and health of K. alvarezii cultures both in vitro and in the field [101][102][103][104]. Brown seaweed extracts as contained in AMPEP have been discovered to potentially activate the natural defense system of K. alvarezii against pathogens and ameliorate the negative impacts of exposure to oxidative bursts, which may result in bleaching of thallus [105].…”