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

Abstract

Seaweed is an important export commodity, making a substantial contribution to the income of coastal fish farmers in South Sulawesi, Indonesia. In particular, kappa carrageenan from Kappaphycus alvarezii is a widely used raw material in the pharmaceutical, food, and other industries and Indonesia is currently ranked as the top carrageenan-producing sea weed exporting country. Crop failure in seaweed cultivation is mostly caused by disease. In Kappaphycus alvarezii crops, ice-ice and epiphytic diseases have been identified, and more information is required to develop ways to control these diseases. This study aimed to investigate these diseases and their effect on growth and carrageenan quality in this species. The research was conducted in Malosoro Bay, Jeneponto District, South Sulawesi. Observations on the effect of disease on seaweeds grown using a long line culture method were conducted "insitu". Observation on carrageenan quality was conducted in the laboratory using a Completely Randomized Design. Growth and carrageenan content data were analyzed using a one way ANOVA. The results showed that presence of these diseases had a significant effect (P<0.05) on K. alvarezii growth, thallus strength and integrity, and carrageenan content.Keywords Carrageenan; Ice-ice; Disease; Epiphytic; Kappaphycus alvarezii; Seaweed BackgroundIndonesia is the leading seaweed producer in the world (FAO, 2016). Currently, the seaweed export from Indonesia has reached 169,113 tons per year or equivalent to USD$ 134,348,000 (Statistics Department of Commerce, 2012) where Sulawesi contributes approximately 60% of the volume. The cultured seaweed in Sulawesi is dominated by Kappaphycus spp. foremost K. alvarezii.Presently, there are several problems faced by the seaweed farmers in Sulawesi that the cultured seaweed has infected by diseases for example epiphyte parasites and ice-ice diseases. Besides that, the quality of the seed is also gradually decreased due to multiple used of the thallus. These conditions led to the production decline and even threatened to harvest failure (Afrianto and Liviawati, 1993).Post-harvest handling is still constrained in conjunction with the drying mainly in the rainy season and drying technique is simple and does not consider the quality of seaweed on the results of the process of drying on the sand, roadside and other techniques that do not support to find the products seaweed quality. Seaweed processing is also just up the seaweed processing of raw materials or semi-finished namely dried seaweed, which is processed into chips and semi refine carrageenan, then exported.The low attention to make a plan in order to increase the maximum added value as a plan activities that make an assessment at the stage of implementation of an activity from upstream to downstream or from aquaculture production to production-ready material. Seaweed production is currently based solely on a two (2) genus that is Kappaphycus spp. reared in sea and Gracillaria spp. reared in brackish-water ponds which both the ge...

Horizontal transmission of ice-ice disease in seaweed Kappaphycus alvarezii (Doty) L. M. Liao (Gigartinales, Rhodophyta)

“…Ice-ice infection also causes a decrease in carrageenan content in K. alvarezii seaweed (Rantetondok & Latama, 2017;Ward et al, 2019). This is indicated by the loss of pigment due to lysis of the cells making up seaweed tissue.…”

Ghi nhận mới và mối quan hệ tiến hóa của epiphyte (<i>Melanothamnus thailandicus</i>) trên rong sụn (<i>Kappaphycus alvarezii</i>) tại Khánh Hòa

“…Các nghiên cứu trên thế giới về bệnh epiphyte cho thấy epiphyte gây ảnh hưởng rất lớn đến năng suất và chất lượng của rong sụn [8,17]. Các công bố đã chỉ ra mùa vụ là nhân tố chính ảnh hưởng đến việc bùng phát dịch bệnh do epiphyte và gây nhiễm khuẩn thứ cấp ở rong sụn [13,20,22].…”

Macroepiphyte biodiversity on Kappaphycus alvarezii surface and its interaction with environment in cultivation centers on Lombok Island, Indonesia

“…The presence of macroepiphyte negatively influences the host's growth and development (Tsiresy et al 2016). Rantetondok and Latama (2017) found a decreasing growth rate of the host due to an epiphytic attack. The presence of epiphytes not only interferes with growth but also causes a decrease in metabolite quality.…”