Respon Pertumbuhan Pada Berbagai Kedalaman Bibit Dan Umur Panen Rumput Laut Eucheuma Cottonii Di Perairan Teluk Palu

Penelitian tentang respon pertumbuhan pada berbagai kedalaman bibit dan umur panen rumput laut bertujuan untuk mengetahui pengaruh kedalaman bibit dan umur panen terhadap pertumbuhan mutlak, produksi, dan produktivitas. Penelitian menggunakan metode bentangan tali ris apung berbentuk empat persegi panjang (18 x 18 meter) yang didesain dalam rancangan lingkungan acak lengkap pola faktorial dengan dua faktor, yaitu faktor kedalaman bibit (K1 20 cm dan K2 50 cm) dan faktor umur panen (U1 40 hari, U2 45 hari, dan U3 50 hari) setelah tanam. Dengan demikian terdapat 6 kombinasi perlakuan dalam 3 ulangan tali ris, sehingga diperoleh 18 satuan unit percobaan. Hasil analisis ragam menunjukkan bahwa, kedua faktor tidak memberikan pengaruh nyata (P>0,05) terhadap pertumbuhan mutlak dan produksi, tetapi berpengaruh sangat nyata (P<0,01) terhadap pruktivitas rumput laut. Namun demikian faktor interaksi berpengaruh sangat nyata (P<0,01) terhadap pertumbuhan mutlak dan berpengaruh nyata (P<0,05) terhadap produksi rumput laut. Bentuk interaksinya merupakan interaksi positif. Hasil uji BNT menunjukkan bahwa, kombinasi perlakuan K1U1 berbeda dan berinteraksi sangat nyata dengan K1U2 dan K1U3. Demikian halnya pada kombinasi perlakuan K2U1 dengan K2U2 dan K2U3, serta kombinasi perlakuan K2U2 dengan K2U3 terhadap pertumbuhan mutlak dengan nilai interaksi sebesar 34,44 g/hari. Selanjutnya kombinasi perlakuan K1U1 berbeda dan berinteraksi nyata dengan K1U2 dan K1U3. Demikian halnya pada kombinasi perlakuan K2U3 dengan K2U1 dan K2U2, serta kombinasi perlakuan K2U1 dan K2U2 terhadap produksi dengan nilai interaksi sebesar 944,98 g

Meristic characters and length-weight relation of climbing perch (Anabas testudineus) from wetlands in Sigi District, Central Sulawesi, Indonesia

Abstract The climbing perch, Anabas testudineus Bloch 1972, is a valued freshwater fish with a wide distribution in South and Southeast Asia. This study examined the meristic counts and length-weight relation of climbing perch from Sigi District, Central Sulawesi, Indonesia, close to the eastern extremity of the species distribution. Specimens collected from wetlands in Sigi District were weighed and measured (total length) to derive length–weight relation (n = 265) and meristic counts (n = 140). Length (L, in mm) – weight (W, in g) relation (W = a·Lb) parameter b = 2.98 overall; for females b = 3.06 while for males b = 2.88. Maximum length Lmax was 163 mm. The meristic formula using median values was D, XVII+8; A, X+9; P, 13; V, I+5; C, 16. Mean scale counts for both male and female climbing perch were: longitudinal 31 and vertical 15. There was no significant between-sex difference in meristic characters. Although the average growth pattern was isometric, males exhibited a slight allometric negative tendency. Low maximum size is consonant with other indications of a population under pressure, reinforcing the need for sustainable, holistic wetland management. In the context of domestication, high variability in meristic characters may indicate high genetic diversity and/or plasticity, which could provide scope for selective breeding.</jats:p

Length-Weight Ratio and Condition Factor of Endemic Fish Oryzias nigrimas (Kottelat, 1990) in Poso Lake, Central Sulawesi

Abstract This research aimed to evaluate the length-weight relationship (LWR) and condition factor of the endemic fish Oryzias nigrimas in Lake Poso and took place from May 2017 until April 2018. A total of 645 O. nigrimas samples were analysed (137 males and 508 females). The length-weight equation was 1.55 × 106 L2.346 for males and W = 3.95 × 106 L2.107 for females. The LWR coefficient b was b = 2.346 for males and b = 2.107 for females (combined value 2.155) which means that b &lt; 3, indicating O. nigrimas is a fish with an allometric negative growth pattern. The condition factor ranged from 0.945-1.091 for males and 0.940-1.107 for females. Overall, the condition factor (Kn) ranged from 0.940 - 1.091, indicating that the sampled fish could be considered in a normal condition. Kn appeared to be related to reproduction with the average Kn value of both male and female fish, being highest in September and February during peak spawning seasons.</jats:p