Effect of various planting distances on growth and carrageenan yield of Kappaphycus alvarezii (doty) using seedlings produced from mass selection combined with tissue-cultured method

Abstract

Kappaphycus alvarezii (Doty), a red seaweed, is the most widely cultivated commodity in Indonesia. However, there is a decline in the cultivation production in the last three years. One way to overcome this problem is by improving the quality of seedlings through a development of farming. Efforts made from these are to develop farming techniques using different planting distances (PD) treatments. This study aimed to determine the effect of different PD on growth and carrageenan yield of K. alvarezii using seedlings produced from mass selection combined with tissue-cultured method. This research was conducted in Marobo coastal waters, Bone District, Muna Regency, SE Sulawesi, Indonesia. This study used a Completely Randomized Design (CRD) with three treatments based on different PD and five replications. The treatments were A: 10 cm PD, B: 15 cm PD, and C: 20 cm PD. The results show that the daily growth rate (DGR) of all treatments tended not to differ significantly. For 10 cm PD, the DGR tended to be higher and significantly different from the other two treatments, 15 cm and 20 cm. DGR averagely were 6.00±1.19%/day, 5.36±1.17%/day, and 5.27±1.62%/day for 10, 15, and 20 cm PD, respectively. The ratio of fresh weight (FW) and dry weight (DW) showed no significant differences among treatments. Ratio of FW:DW treatments of 10 cm, 15 cm, and 20 cm were 8.34:1, 9.58:1, and 8.98:1, respectively. For carrageenan yield, the treatment of 20 cm PD showed highest yield and it was significantly different from other treatments. Seaweed diseases and epiphytes found during this study were ice-ice and epiphytes (Sargassum polychystum).