Judul: Flower Color Characterization, Metabolite Profiling and Flavonoid-Related Gene Expression in Sudamala Barak Marigold Flowers (Tagetes patula).
Abstrak: Marigold (Tagetes spp.) is a floricultural plant belonging to the Asteraceae family and is extensively cultivated in Indonesia, particularly in the province of Bali, where it is used as a prop in religious ceremonies. Marigold flowers exhibit limited color variations including yellow, orange, and red, with flower color being a critical characteristic that determines the commercial value of floricultural plants. Therefore, there is a need to develop marigold varieties to enhance flower color variation. Traditional breeding techniques such as hybridization and mutation have limitations due to their random nature, which hinders the creation of specific flower color variations. These challenges can be addressed through biotechnology-based breeding techniques such as genetic engineering, which require information on biochemical contents and gene expression patterns in desired pigment biosynthesis pathways. Sudamala Barak Marigold (T. patula) exhibits a unique red color change in its flowers from early to late developmental stages, likely originating from carotenoid, flavonoid, and anthocyanin pigments. This research aims to investigate flower color changes, identify metabolite profiles, and analyze gene expression patterns related to the flavonoid biosynthesis pathway across four stages of flower development. The genetic material used in this study includes Sudamala Barak marigold flowers at four developmental stages: closed buds (stage 1), semi-open buds (stage 2), open flowers (stage 3), and fully open flowers (stage 4). Sudamala Barak marigolds were clonally propagated using cuttings and grown at the Pasir Sarongge Experimental Garden, Cianjur, West Java, at an altitude of 1100 meters above sea level (masl). In metabolomic analysis, samples were extracted and metabolized with 70% methanol containing 0.1% HCl, and the data obtained were analyzed using MetaboAnalyst software. For gene expression analysis, RNA extraction and cDNA synthesis were performed, and the data were processed using Livak and Schmittgen methods. From this research, Sudamala Barak marigold flowers experienced a color change from moderate reddish brown at stage 1 to strong orange at stage 4. A total of 58 compounds have been identified during four stages of development, with 32 compounds present in all stages. The main compound groups include amino acids, phenols, flavonoids and terpenoids, where flavonoids, especially flavonols such as patuletin, isorhamnetin, and others, are thought to contribute to the formation of yellow color in flowers. Gene expression analysis shows that early biosynthesis genes (CHS, CHI, F3H) and late biosynthesis genes (F3'H, DFR, ANS, UFGT, OMT) play a role in pigment formation, with the highest expression occurring at different stages. It was confirmed that the red color of the flowers was caused by anthocyanins., Marigold (Tagetes spp.) merupakan tanaman florikultura yang termasuk ke dalam famili Asteraceae dan banyak dibudidayakan di Indonesia khususnya provinsi Bali karena digunakan sebagai salah satu properti dalam upacara keagamaan. Bunga marigold memiliki variasi warna terbatas yaitu kuning, oranye dan merah, sedangkan warna bunga merupakan ciri penting yang menentukan nilai komersial tanaman florikultura. Oleh karena itu, diperlukan perakitan varietas marigold untuk meningkatkan variasi warna bunga. Teknik pemuliaan seperti hibridisasi dan mutasi memiliki kelemahan yakni bersifat acak, sehingga belum dapat diciptakan variasi warna bunga yang spesifik. Kendala tersebut dapat diatasi dengan teknik pemuliaan berbasis bioteknologi seperti rekayasa genetik yang memerlukan
Keyword: gene expression, metabolit sekunder, ekpresi gen, analisis LCMS tidak tertarget, analisis kuantitatif PCR, quantitative PCR analysis, secondary metabolites, flavonoid, flavonoid, untargeted LCMS analysis

Judul: Flower Induction of Marigold ‘Sudamala  Barak’ (Tagetes patula) with Plant Growth Regulator
Abstrak: Tagetes patula merupakan tanaman multifungsi, terutama pada bagian bunganya. Salah satu varietas dalam negeri yang potensial dikembangkan adalah Sudamala Barak, namun varietas ini memiliki umur berbunga yang lama yaitu 13-15 minggu sejak ditanam. Penelitian ini bertujuan mengetahui pengaruh ZPT (zat pengatur tumbuh) BAP (benzyl amino purine), GA3 (gibberellin acid), dan PBZ (paclobutrazol) terhadap respon pembungaan tanaman marigold ‘Sudamala Barak’ serta mengetahui konsentrasi terbaiknya. Penelitian dilaksanakan di dalam rumah kaca Kebun Percobaan Leuwikopo, IPB pada bulan September 2023 hingga Maret 2024. Penelitian ini menggunakan rancangan kelompok lengkap teracak dengan satu faktor yaitu jenis serta konsentrasi ZPT. Terdapat 10 taraf perlakuan yang terdiri dari kontrol (tanpa ZPT), BAP (50, 100, 150 ppm), GA3 (100, 200, 300 ppm), dan PBZ (50, 100, 150 ppm). Pengamatan meliputi karakter generatif dan vegetatif. Hasil penelitian menunjukkan pemberian ZPT berpengaruh nyata terhadap jumlah bunga, bobot total bunga, panjang tunas, panjang daun, dan panjang anak daun. Persentase tanaman berbunga tertinggi ditemukan pada perlakuan GA3 200 ppm (66,6%). Pengaruh ZPT terhadap karakter generatif menunjukkan GA3 200 ppm menghasilkan jumlah bunga dan bobot total bunga terbesar dibandingkan seluruh perlakuan lainnya. Hasil percobaan ini menunjukkan bahwa GA3 200 ppm berpotensi menginduksi pembungaan T. patula ‘Sudamala Barak’. Pada karakter vegetatif, pemberian BAP memberikan pengaruh yang netral kecuali pada BAP 150 ppm menghambat pemanjangan tunas, sementara GA3 mendorong pemanjangan tunas, dan PBZ menghambat pertumbuhan vegetatif., Tagetes patula is a multifunctional plant, especially in its flower parts. One potential domestic variety to be developed is Sudamala Barak, however this variety has a long juvenile period, which lasts for 13-15 weeks since planting. This study aimed to determine the effect of PGRs (plant growth regulation) BAP (benzyl amino purine), GA3 (gibberellic acid), and PBZ (paclobutrazol) on the flowering response of the marigold 'Sudamala Barak' and to determine the best concentrations. The research was conducted in the greenhouse of Leuwikopo Experimental Station, IPB University from September 2023 to March 2024. The experiment applied a completely randomized design with one factor, PGRs. There were 10 treatment levels consisting of control (without PGRs), BAP (50, 100, 150 ppm), GA3 (100, 200, 300 ppm), and PBZ (50, 100, 150 ppm). Observations included generative and vegetative characters. The results showed that the application of PGRs significantly affected the number of flowers, total flower weight, length of formed shoots, leaf length, and leaflet length. The highest percentage of plant flowering was found on GA3 200 ppm (66,6%). GA3 200 ppm treatment also produced the largest number of flowers and total flower weight compared to all other treatments. This experiment results imply that GA3 200 ppm has the potential inducer to induce flowering in T. patula ‘Sudamala Barak’. In the vegetative characteristics, the application of BAP had a neutral effect except at 150 ppm, where it inhibited shoot elongation, while GA3 promoted shoot elongation, and PBZ inhibited vegetative growth.
Keyword: benzyl amino purine, flower mechanism, gibberellic acid, paclobutrazol, production

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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