The purpose of this study was to determine the effect of different seedling sources on growth and carrageenan yield of K. alvarezii. There were three various seedlings sources used in this study: local strain, tissue-cultured seedlings, and seedlings resulting from mass selection combined with tissue–cultured method called “prof’. This research was over three months (August-October 2018) in Marobo coastal waters, Bone District, Muna Regency SE Sulawesi using the longline method. The results showed that the daily growth rate (DGR) during this study tended to fluctuate among treatments “prof’ and tissue-cultured seedlings had higher the DGRs than local strain seedlings. Ratio fresh weight (FW) and dry weight (DW) showed no significant differences among different seedling sources. The mean FW: DW ratio showed the local strain had the highest ratio (10.10:1) followed by tissue-cultured seedlings (9.88:1) and prof (9.06:1). Furthermore, the local strain showed a significant difference in carrageenan yield from the “prof’ and tissue-culture seedlings. Local strain seedlings showed the highest carrageenan yield (40.58±2.51%) followed by tissue-cultured seedling (35.35±2.79%) and prof seedlings (33.88±2.09%). Ice-ice disease and epiphyte (Sargassum polychystum) were found during this study. This study showed that prof and tissue-cultured seedlings greater potential for improved seaweed farming.

This research was conducted for four months from January to May, 2019 in Sasara coastal Waters, Kulisusu Bay, Buton Utara, SE Sulawesi, Indonesia. The aim of this research was to determine the best oblique incision length (OIL) to use in slide-slipped grafting using tissue cultured and local seedlings in terms of the growth and carrageenan yield of the seaweed Kappaphycus alvarezii. The treatments used in this study were A: 25-mm OIL, B: 30-mm OIL and C: 35-mm OIL. After 18 days, grafts using all OILs were successfully attached together. The new seedlings were then cultivated for 45 days. The results showed that the daily growth rate (DGR) did not differ significantly between treatments. The 25-mm OIL treatment had the highest DGR (3.98±0.97 %.day−1) followed by 35-mm OIL(3.90 ± 1.32%.day−1 and 30-mm OIL (3.69 ± 0.91 %.day−1). The ratio of fresh weight (FW) to dry weight (DW) also showed no significant differences among treatments. FW:DW ratios of treatments 25 mm OIL, 30 mm OIL, and 35 mm OIL were 8.13:1, 7.42:1, and 5.78:1, respectively. For carrageenan content, 30-mm OIL seedlings of showed higher content but it was not significantly different from the other treatments. Water quality parameters were: salinity 24-32 ppt; temperature 29-31 ° C; nitrate 0.336-0.432 mg.l−1; phosphate 0.195-0.542 ppm; and turbidity 3,124-9,331 NTU.

Acadian Marine Plant Extract Powder (AMPEP) is a commercial organic fertilizer extract from brown seaweed, Ascophyllum nodosum. This study aimed to examine the effect of different concentrations of AMPEP extract on K. alvarezii “Kulisusu” seedlings. We investigated the daily growth rate (DGR), ratio of wet weight and dry weight (FW: DW ratio), and the survival rate of seedlings in encircling tanks. Concentrations of AMPEP used in this study were 0.2, 0.4, 0.6, 0.8, 1.0 g L-1 at 30 min immersion time and without AMPEP as control for a 1-month cultivation period. The results showed that the 0.2 g L-1 of AMPEP showed higher DGR in 6-18 days of culture period (3.43-4.25%/day), the 0.6 g L-1 was higher in the 24 days culture period (3.50%/day), and the 0.8 g L-1 concentration was higher in the 30 days of culture period (3.76%/day). For FW: DW ratio, 0.2 g L-1 of AMPEP concentration showed the highest ratio (8.73:1) and was significantly different from the other treatments (p<0.05). In addition, all treatments showed a high survival rate (>93.33%) with minor variation amongst the treatments (p>0.05). The results concluded that using 0.2 g L-1 of AMPEP in encircling tanks was suitable for seedling development.

Wa Iba, Citra Utami and Abdul M. Balubi. 2019. The Growth of Chlorella vulgaris Cultured in Liquid Organic Fertilizer of Water Hyacint H (Eichhornia crassipes) at Different Salinities, Indonesia Aquacultura Indonesiana, 20 (2) : 117-126. This study aims to determine the effect of salinity on the growth of microalgae C. vulgaris cultured in 5% concentration of water hyacinth liquid organic fertilizer. The research used a completely randomized design with four salinity treatments at 30, 35, 40 and 45 ppt in triplicates. The volume of culture media was 150 mL that consisted of 142.5 ml of sterile sea water and 7.5 ml of water hyacinth organic fertilizer. The increase in microalgae cell density was observed every other day using haemocytometer under light microscope. The culture was harvested after they reached stationary phase at day 8. Culture age (p= 0,00<0.05) and salinity (p= 0,00<0.05) affected the growth, dry weight and biomass productivity of C. vulgaris. Cells density and yield in all salinities tested was significantly different (p= 0,00<0.05) at stationary phase of growth. Higher cell density, specific growth rate, yield, dry weight and biomass productivity were observed in 40 ppt salinity compared to other salinities. At 40 ppt, cell density was 85.33 x 10 4 cells. ml-1 as well as specific growth rate that was at 0.839 cells.day-1 , with the highest average yield of C. vulgaris was observed on day 6 and day 8 (exponential to stationary phase) at 115, 3 x 10 4 cells.ml-1. Similarly, considerably higher dry weight at 40 ppt was observed at 0.038 g.L-1 with biomass productivity at 0.032 g.L-1 .day-1 compared to other salinities tested However these results were not significantly different (p=0.7>0.05) from other salinities. This study suggested that 40 ppt can be used to culture C. vulgaris in 5 % concentration of water hyacinth organic medium to obtain better growth and higher biomass production.

ABSTRAK Penelitian ini di lakukan di Unit Pembenihan Rakyat Kuncup Mekar di Desa Duriasih Kecamatan Wongeduku Kabupaten Konawe pada bulan juli sampai Agustus 2018 dengan tujuan untuk mengkaji proses pemesanan benih ikan bawal, proses pengantaran dan proses pembayaran komiditi ikan bawal dari balai benih sleman, mengkaji proses budidaya benih ikan bawal, dan mengkaji besar keuntungan dari tiap penjualan. Metode yang di gunakan dalam penelitian ini adalah metode studi kasus.Penelitian ini mengambil responden seorang pengusaha benih ikan bawal dengan menggunakan tekhnik wawancara dan observasi untuk mengumpulkan data. Adapun hasil dari penilitian ini adalah kegiatan pembudidayaan benih ikan bawal pada unit pembenihan rakyat kuncup mekar pada tahap budidaya mulai dari  proses pemesanan benih di balai benih slemen  dengan umur benih sekitar 2 minggu dengan harga 20Rp/ekor yang dimana pembayaran benih ini di lakukan melalui transfer rekening ke bank, serta pengiriman benih ikan bawal melalui jalur transportasi udara yaitu pesawat, Proses budidaya benih ikan bawal melalui tahap pemisahan benih ikan bawal cuman membutukan waktu selama 30 hari sehinga mencapai ukuran 3-12 mm dengan harga Rp 500 – Rp 3.000/ekor benih, dan keuntungan dari penjualan benih ikan bawal selama satu kali produksi adalah sebesar sebesar Rp. 32.659.393.-Kata kunci :Benih ikan bawal, Budidaya benih ikan bawal,