Ikan mas Mustika merupakan varietas unggul ikan mas hasil seleksi tahan penyakit Koi Herpes Virus (KHV). Secara laboratoris, uji tantang ikan mas Mustika dengan KHV menghasilkan sintasan lebih dari 90%. Namun demikian, performa ikan mas Mustika di lingkungan budidaya terkait pertumbuhan dan tingkat produktivitasnya belum banyak dikaji. Penelitian ini bertujuan mengevaluasi performa ikan mas Mustika sebagai varietas unggul tahan KHV di beberapa lokasi sentra budidaya. Penelitian dilakukan di kolam air deras (KAD) di Tanjungsiang, Subang; serta karamba jaring apung (KJA) di Waduk Jatiluhur, Purwakarta; Waduk Cirata, Cianjur; dan Waduk Darma, Kuningan. Sebagai pembanding digunakan ikan mas Majalaya yang berasal dari unit pembenihan rakyat (UPR) setempat. Penelitian dilakukan dengan tiga kali ulangan selama 90 hari. Hasil penelitian menunjukkan bahwa performa ikan mas lebih dipengaruhi oleh faktor lingkungan daripada faktor genetik, serta interaksi kedua faktor tersebut. Hasil penelitian juga menunjukkan bahwa kualitas perairan di Waduk Darma lebih rendah dibanding lokasi lainnya. Di lokasi tersebut, ikan mas Mustika mempunyai pertumbuhan, produktivitas, dan rasio konversi pakan sebesar 2,81%/hari; 13,42 kg/m2; dan 1,43 secara nyata lebih baik daripada varietas pembanding, sebesar 2,21%/hari; 8,16 kg/m2; dan 2,54. Di lokasi lainnya, performa ikan mas Mustika tidak berbeda nyata dengan varietas pembanding. Hal ini mengindikasikan bahwa ikan mas Mustika mempunyai toleransi yang lebih baik terhadap kondisi lingkungan perairan yang buruk, daripada varietas pembanding.Mustika is the newly produced superior variety of common carp strains resistant to Koi Herpes Virus (KHV). The challenge test of Mustika common carp against KHV resulted in a survival rate of more than 90%. However, the information on the growth and productivity of Mustika common carp in culture conditions is not yet available to supplement its superior resistance to KHV. This study was aimed to evaluate the performance of Mustika as a superior variety of common carp resistant to KHV resistance through multi-location tests which were in: running water ponds (KAD) in Tanjungsiang, Subang; floating net cages (KJA) in Jatiluhur Reservoir, Purwakarta; Cirata Reservoir, Cianjur; and Darma Reservoir, Kuningan. In all trial locations, Majalaya carp from the local hatchery (UPR) were used as the comparison population. The study was conducted for 90 days with three replications. The result showed that the performance of the carp was more affected by the environmental factor than both genetic and interaction of genetic >< environment factors. In Darma reservoir which has poorer water quality conditions, Mustika common carp had better growth, productivity and food conversion ratio of 2.81%/day, 13.42 kg/m2, and 1.43, respectively, compared to that of the comparison population of 2.21%/day, 8.16 kg/m2, and 2.54. Among the locations used in the multi-location test, the performances of Mustika common carp and the comparison population were not significantly different. These results indicate that Mustika common carp is more tolerant of being cultured in poorer water quality conditions

ABSTRAKTeluk Jakarta merupakan salah satu ekosistem perairan dengan tingkat pencemaran organik tertinggi di dunia. Kondisi ekologis perairan Teluk Jakarta akan memengaruhi kondisi ekosistem, termasuk sebaran bakteri heterotrofiknya. Penelitian ini bertujuan untuk mengetahui dinamika sebaran bakteri heterotrofik di perairan Teluk Jakarta. Pengambilan sampel dilakukan sebanyak 4 kali ulangan selama tahun 2013. Data yang digunakan berupa data primer dan sekunder. Hasil penelitian menunjukkan kelimpahan bakteri heterotrofik berfluktuasi dan relatif tinggi pada daerah dekat dengan muara sungai dan semakin menurun kelimpahannya di daerah laut. Kelimpahan tertinggi didapat di Stasiun 10 dengan kepadatan sebesar 3,5 × 10 6 CFU/ml dan kelimpahan terendah didapat di stasiun 1 dengan kepadatan sebesar 1,8 × 10 5 CFU/ml. Kepadatan tertinggi didapat pada bulan Oktober dengan rerata sebesar 1,3 × 10 6 CFU/ml dan kepadatan terendah didapat pada bulan Juli dengan rerata sebesar 3,5 × 10 5 CFU/ml. Kelimpahan bakteri heterotrofik memiliki hubungan erat dengan klorofil-a.Kata kunci: bakteri heterotrofik, dinamika sebaran, teluk Jakarta ABSTRACT Jakarta Bay is one of the aquatic ecosystems with the highest level of organic pollution in the world. Ecological condition of Jakarta Bay's water will affect the ecosystem, including the distribution of heterotrophic bacteria. This study aims to determine the dynamics of the heterotrophic bacteria distribution in the Jakarta Bay. Sampling was conducted four times in 2013. Primary and secondary data was used in this research. The results showed that the abundance of heterotrophic bacteria fluctuated and were relatively high in the area near the mouth of the river and it decreased towards the outer of the bay. The highest abundance was obtained at Station 10 with 3,5 × 10 6 CFU/ml density and the lowest one was at Station 1 with 1,8 × 10 5 CFU/ml density. The highest density was obtained in October with an average of 1,3 × 10 6 CFU/ml and the lowest density was obtained in July with the average of 3,5 × 10 5 CFU/ml. Abundance of heterotrophic bacteria had strong relationships with chlorophyll-a.

Ikan mas (Cyprinus carpio) merupakan komoditas budidaya yang mudah beradaptasi dengan berbagai kondisi lingkungan. Penelitian ini bertujuan mempelajari pengaruh genotipe, lingkungan, dan interaksi antara genotipe dengan lingkungan terhadap stabilitas penampilan fenotipik ikan mas dalam kegiatan budidaya. Rancangan percobaan menggunakan rancangan faktorial 3 x 5 dengan lima ulangan. Lima strain ikan mas, yaitu Rajadanu, Sutisna, Majalaya, Wildan, dan Sinyonya dipelihara secara komunal di dalam tiga model wadah budidaya, yaitu kolam beton, kolam jaring, dan kolam tanah, selama 90 hari. Hasil penelitian menunjukkan bahwa penampilan fenotipik ikan mas dipengaruhi oleh genotipe, lingkungan dan interaksi kedua faktor tersebut. Strain Sutisna dan Wildan mempunyai nilai sintasan yang paling baik di semua lingkungan dibanding tiga strain lainnya. Strain Sutisna mempunyai pertumbuhan terbaik di kolam tanah sedangkan strain Wildan di kolam jaring. Hal ini menyebabkan kedua strain tersebut menghasilkan biomassa panen terbaik pada lingkungan yang berbeda. Hasil analisis stabilitas menunjukkan bahwa kelima strain ikan mas dalam penelitian ini relatif tidak stabil dan mempunyai respons yang berbeda jika dipelihara pada lingkungan yang berbeda. Strain Wildan dan Rajadanu merupakan strain ikan mas yang mempunyai respons terhadap perbedaan lingkungan paling tinggi. Strain dengan karakteristik tersebut akan mempunyai performa terbaik pada lokasi dan kondisi pemeliharan yang sesuai dengan kebutuhannya, tetapi mempunyai penampilan fenotipik yang rendah jika kondisi lingkungan budidayanya tidak sesuai. Strain Sutisna, Sinyonya, dan Majalaya merupakan strain ikan mas dengan daya responsi terhadap lingkungan lebih rendah. Karakteristik ini menyebabkan penampilan fenotipik ketiga strain tersebut relatif stabil pada semua lokasi dan kondisi budidaya, meskipun tidak bisa mencapai hasil yang maksimal.Common carp (Cyprinus carpio) is known as fish species highly adaptable to various environmental conditions. This study aimed to evaluate the effect of genotype, environment, and their interaction in phenotypic performance stability of common carp. The experimental design used a 3 x 5 factorial design with five repetitions. Five strains of common carp, namely Rajadanu, Sutisna, Majalaya, Wildan, and Sinyonya were stocked communally for 90 days in three culture systems: concrete pond, net cage pond, and earthen pond. The result showed that the phenotypic performance of common carp was influenced by genotype, environment, and their interaction. Sutisna and Wildan strains have a higher survival rate compared to other strains in all culture systems. Sutisna and Wildan strains have the best growth performance in the earthen pond and net cage pond, respectively. Both strains also have the highest biomass production at harvest in all culture systems. Based on the stability performance analysis, Wildan and Rajadanu have the highest response to the different environmental conditions. Strains with this characteristic perform best in different locations or culture systems as long as the environmental conditions are suitable. However, these fish will likely perform poor in the unsuitable culture environment. Sutisna, Sinyonya, and Majalaya are carp strains with lower responsiveness to environmental change. Such characteristic causes the phenotypic performance of these three strains cannot achieve the maximum results, yet it is relatively stable in all locations.

Upaya meningkatkan performa budidaya ikan mas dapat dilakukan melalui seleksi. Salah satu faktor keberhasilan program seleksi adalah tingkat keragaman genetik yang tinggi pada populasi bahan seleksi. Penelitian ini bertujuan membentuk dan mengevaluasi keragaan populasi dasar (F-0) ikan mas sebagai populasi awal dalam kegiatan seleksi. Materi kegiatan ini adalah populasi sintetis yang merupakan penggabungan lima strain ikan mas, yakni Majalaya, Rajadanu, Sutisna, Wildan, dan Sinyonya. Pembentukan populasi dasar (F-0) dilakukan menggunakan metode seleksi berdasarkan indeks individu dari empat karakter fenotipik, yakni panjang, tebal, tinggi, dan bobot. Masing-masing karakter diberi nilai 1:1:1:2. Titik cut-off seleksi populasi dasar (F-0) sebesar 60%. Hasil penelitian menunjukkan bahwa populasi F-0 ikan mas yang dibentuk terdiri atas individu hasil seleksi sebanyak 1.662 ekor, dengan komposisi 723 jantan dan 939 betina. Populasi dasar (F-0) sintetis hasil seleksi tersebut mempunyai keragaman genetik lebar karena diperoleh dari 25 populasi hasil persilangan dalam proporsi yang berbeda-beda. Kontribusi genetik paling besar dalam pembentukan populasi F-0 tersebut diberikan oleh strain Sutisna (22,55%) diikuti Majalaya (21,52%), Rajadanu (20,84%), Wildan (18,33%), dan Sinyonya (16,75%). Tingginya tingkat keragaman genetik populasi dasar ini berpotensi besar dalam keberhasilan kegiatan pemuliaan ikan mas khususnya melalui program seleksi.Improvement on phenotipic characters in common carp culture can be achieved through selection. In order to achive that goal, A base population (F-0) must be initially formed. This study aimed to establish and evaluate the performance of base populations (F-0) common carp. The synthetic populations had been created which were the combinations of five common carp strains, namely Majalaya, Rajadanu, Sutisna, Wildan, and Sinyonya. These common carp base populations (F-0) were created through a selection based on the individual index of four phenotypic characters, i.e. length, thickness, height and weight, which scored 1:1:1:2, respectively. The selection cut-off in this program was 60%. The results showed that the base populations (F-0) of common carp formed from 1,662 selected fish consisted of 723 males and 939 females. These F-0 populations have wide genetic diversity as the crossing results of 25 populations with different proportions. The Sutisna strain (22.55%) had the most genetic contribution in the formation of the F-0 populationss followed by Majalaya (21.52%), Rajadanu (20.84%), Wildan (18.33%), and Sinyonya (16.75%). High level of genetic variation in this base population has great potential in the success of common carp breeding activities, especially trough selection program.

Benih ikan mas telah mengalami penurunan kualitas genetik yang menyebabkan penurunan performa fenotipik di lingkungan budidaya. Salah satu upaya perbaikan genetik adalah melalui pembentukan populasi sintetis yang merupakan penggabungan potensi genetik beberapa populasi plasma nutfah ikan mas. Penelitian ini bertujuan membentuk dan mengevaluasi performa genotipik dan fenotipik populasi sintetis ikan mas, yang merupakan penggabungan dari strain Rajadanu, Majalaya, Sutisna, Wildan, dan Sinyonya. Performa genotipik dievaluasi menggunakan metode mikrosatelit DNA, sedangkan performa fenotipik dievaluasi menggunakan analisis biometrik terkait kegiatan budidaya. Hasil penelitian menunjukkan bahwa nilai keragaman genetik populasi sintetis lebih tinggi 55,0%-287,5% dengan tingkat inbreeding 40,0%-77,14% lebih rendah dibanding populasi-populasi pembentuknya. Hal ini berdampak terhadap performa fenotipik populasi sintetis yang lebih baik, diindikasikan dengan peningkatan panjang, bobot akhir, dan tingkat produktivitas, masing-masing sebesar 2,5%-20,6%; 9,4%-61,8%; dan 18,2%-66,0% lebih baik dibanding populasi-populasi pembentuknya. Peningkatan kualitas genetik dan performa fenotipik populasi sintetis ini memberikan peluang untuk memperbaiki kualitas benih ikan mas pada kegiatan budidaya.Common carp in Indonesia has experienced a decline in genetic quality. The progressive decline leads to a significant decrease in carp performance in the farming environment. One of the efforts to genetically improve carp growth performance is through developing synthetic carp populations, which is a blend of the genetic potentials from several germplasm populations. This study aimed to form and evaluate the performance of genotypic and phenotypic of synthetic populations of common carp, blended from five strains of common carp, i.e., Rajadanu, Majalaya, Sutisna, Wildan, and Sinyonya. The genotypic performance was evaluated using the DNA microsatellite method. The phenotypic performance was assessed using biometric analysis, especially in terms of culture performance. The results showed that the genotypic performance of the synthetic populations of common carp was better than that of the founder strains. This performance was indicated by higher genetic diversity values, about 55.0%-287.5% and lower levels of inbreeding, about 40.0%-77.1%, compared with their founder populations. Phenotypic performance of the synthetic populations is also better than their founder populations, indicated by higher body length, weight, and productivity, about 2.5%-20.6%, 9.4%-61.8%, and 18.2%-66.0%, respectively. The improvement on genetic quality and phenotypic performance of the synthetic population provide opportunities to improve the quality of common carp fry in aquaculture activity.