Acclimatization of micropropagated Kappaphycus alvarezii (Doty) Doty ex Silva (Rhodophyta, Solieriaceae) in outdoor nursery system

Abstract

Seaweed farming has been identified as one of the entry point projects (EPPs) in Malaysia since the government introduced the Economic Transformation Programme, which aims to increase seaweed production to 150,000 t annually by 2020. To achieve this goal, micropropagation and subsequent acclimatization of the micropropagated seaweeds to the open sea is one of the available options to solve the seedling shortage problem. Acclimatization is an important process in which micropropagated seaweeds adjust to gradual changes in environments such as temperature, humidity, photoperiod, and pH. Success acclimatization is an important key for the seaweed tissue culture industry to move forward, and therefore, the protocol of acclimatization of micropropagated Kappaphycus alvarezii has been extensively optimized in this study. Direct planting out of the micropropagated seaweeds to the open sea without goingthrough the nursery acclimatization phase may cause shock to the seaweeds due to sudden changes in environmental conditions. In a 2-week acclimatization study, seedlings were found to achieve optimum growth when cultivated in seawater enriched with mixed-algae fertilizer, natural seaweed extract (NSE), under a regimen of daily medium change and culture density of 0.40 g L −1 . The acclimatized K. alvarezii has achieved 83.33 ± 5.77 % of survival in the seaweed farm with normal physiology and no epiphyte coverage. This study has provided useful information for seaweed cultivators to enhance the survival rate of micropropagated K. alvarezii through nursery acclimatization prior to serve as seedlings for commercial seaweed cultivation.

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.…”

Chemical composition of farmed and micropropagated Kappaphycus alvarezii (Rhodophyta, Gigartinales), a commercially important seaweed in Malaysia

“…Micropropagation of K. alvarezii was carried out according to the optimized protocols developed by Yong et al (2014a), followed by acclimatization (Yong et al 2014b) prior sea farming. After 4 weeks of cultivation in the seaweed farm, 10 crops of K. alvarezii from each source of propagation were harvested and cleaned to remove epiphytes and unwanted particles.…”

Pertumbuhan dan Perkembangan Eksplan Rumput Laut Gracilaria verrucosa dan Gracilaria gigas pada Aklimatisasi di Tambak

“…Menurut Yong et al (2014), suatu organisme bila dipindahkan ke habitat baru akan melakukan penyesuaian diri terhadap kondisi lingkungan baru, rumput laut yang cepat menyesuaikan diri dengan lingkungan barunya akan mampu tumbuh dengan cepat, sehingga pertumbuhan optimal. Perbedaan pertumbuhan eksplan G. verrucosa dan G. gigas terjadi karena adanya perbedaan kemampuan beradaptasi pada lingkungan tambak.…”

“…Kesuksesan proses aklimatisasi merupakan kunci penting untuk industri kultur jaringan rumput laut. Pemeliharaan rumput laut hasil kultur jaringan tanpa proses aklimatisasi dapat menyebabkan kematian rumput laut karena akan mengalami stres akibat perubahan kondisi lingkungan yang mendadak (Yong et al, 2014 …”

“…Batas toleransi nitrat terendah untuk pertumbuhan alga adalah 0,1-3 mg.L -1 dan kandungan fosfat dalam perairan pada kisaran 0,051-0,2 mg.L -1 digolongkan dalam kategori kesuburan tinggi (Moore, 1991;Effendi, 2003 Proses aklimatisasi bagian dari rangkaian proses bioteknologi, merupakan proses adaptasi eksplan dengan lingkungan budidaya. Keberhasilan eksplan dalam beradaptasi dengan lingkungan budidaya merupakan kunci keberhasilan produksi masal bibit rumput laut hasil kultur jaringan (Rorrer dan Cheney, 2004;Yong et al, 2014 …”