Buitenzorg: Journal of Tropical Science

Effect of fermented coconut waste and rice bran feed using Rhiodiotorula taiwanensis UNJCC Y-171 on Black Soldier Fly (BSF) larvae growth and proximate composition

Yunita Sari, Melta Rini Fahmi; Dalia Sukmawati — Thu, 26 Jun 2025 00:00:00 +0000

Black soldier fly (BSF) larvae, or maggots, are a promising alternative protein-rich feed for aquaculture. This study aims to evaluate the effect of fermented feed made from coconut pulp and rice bran using the yeast Rhodotorula taiwanensis UNJCC Y-171 on maggot growth and proximate composition. The study was conducted from June to August 2024 at the Universitas Negeri Jakarta and the Ornamental Fish Aquaculture Research Center. The treatments included a control group (K) and fermentation using yeast at 30% (A) and 40% (B) concentrations. Measurements were taken on days 10, 13, 16, and 19. The results showed that fermented feed significantly increased maggot wet weight and body length, particularly in treatment B. On day 16, the wet weight of maggots in treatment B reached 182.00±45.14 g, higher than the control (77,00±52.03 g). The body length of maggots in treatment B was also greater (1.59±0.12 cm) than in the control (1.19±0.09 cm). Proximate analysis indicated that maggots in treatment B had a higher fat content (15.57%) compared to the control (12.11%), while crude fiber content was lower (1.27% compared to 1.63%), indicating improved feed efficiency. Although the protein content in treatment B (12.29%) was slightly lower than in the control (13.27%), fermentation with R. taiwanensis UNJCC Y-171 enhanced nutrient bioavailability. This study confirms that feed fermentation with R. taiwanensis UNJCC Y-171 at a 40% concentration optimally improves both maggot growth and nutritional quality. Therefore, this method has the potential to serve as a more cost-effective alternative feed for aquaculture.

Keywords: Rhodotorula taiwanensis, feed fermentation, maggot, proximate analysis, feed efficiency

Modulating flowering for breeding efficiency and biomass optimization: A molecular and biotechnological review

Aqwin Polosoro — Thu, 26 Jun 2025 00:00:00 +0000

Regulation of flowering time is a critical determinant of plant reproductive success and a key trait for optimizing crop adaptation, yield stability, and breeding efficiency. This review highlights recent advances in the molecular pathways controlling flowering, including photoperiod sensing, vernalization and temperature response, autonomous and hormonal regulation, and floral integrator networks. Key genes such as FT, SOC1, FLC, TFL1, and Ghd7 serve as central nodes within these interconnected pathways. The application of genetic engineering tools—including gene overexpression, CRISPR/Cas-mediated knockouts, promoter editing, and transient expression systems—has enabled precise manipulation of flowering phenology across a wide range of crops. These strategies have accelerated fast-track breeding in temperate and tropical perennials and facilitated the enhancement of vegetative biomass in forage and industrial crops through delayed flowering. However, the deployment of flowering-modified genotypes presents challenges, including environmental interactions, phenological trade-offs, biosafety regulation, and potential ecological impacts. Future directions should emphasize the integration of flowering time control with speed breeding platforms, genomic selection, and climate-adaptive trait design, tailored to species—and region—specific requirements. Such multidisciplinary approaches will be vital to advancing crop resilience, productivity, and sustainability under changing environmental conditions.

Keywords: flowering time regulation, genetic engineering, FT gene, fast-track breeding, biomass optimization

Characterization and Economic Feasibility of Citrus aurantifolia ‘Nimas Agrihorti’ Cultivar as a Potential Biopharmaceutical Commodity in Indonesia

Thu, 26 Jun 2025 00:00:00 +0000

‘Nimas Agrihorti’ is a citrus cultivar developed to fulfil the increasing domestic demand for biopharmaceutical-grade citrus in Indonesia. Its development aligns with the growing public interest in health-promoting agricultural products. This study aimed to evaluate the morphological characteristics, chemical composition, and economic viability of ‘Nimas Agrihorti’ as a biopharmaceutical citrus. Field observations were conducted from June 2019 to October 2020 at the Banjarsari Experimental Field, Bayeman Village, Probolinggo, East Java. Morphological assessments followed the Descriptor List for Citrus by IPGRI, and chemical analyses were performed at the Post-Harvest Laboratory of Brawijaya University, Malang. Economic feasibility was assessed by calculating production costs and revenues over a 2-year cultivation cycle. ‘Nimas Agrihorti’ exhibited favorable morphological traits, including large fruit size (72–82 g), yellow skin, and sweet taste. Chemical analysis revealed vitamin C content of 34.8 mg/100 g and low acidity at 0.45%. The total production cost over 2 years was IDR 42,640,000.00 (equivalent to USD 2,584), with total revenue amounting to IDR 77,360,000.00 (equivalent to USD 4,688), resulting in a Revenue-Cost (R/C) ratio of 2.81. The combination of desirable morphological and chemical characteristics, along with strong economic returns, indicates that ‘Nimas Agrihorti’ holds significant potential for development as a biopharmaceutical citrus cultivar in Indonesia.

Keywords: citrus, cultivar, biopharmaceutical products, economic feasibility

Micromorphological Characterization and DNA Barcoding of Durio macrantha Kosterm. from the Bogor Botanical Garden Collection

Mahat Magandhi, Diyana Sabila Rusydina, Arnia Sari Mukaromah — Thu, 26 Jun 2025 00:00:00 +0000

Durio macrantha is an endemic species first discovered in 1981 in Gunung Leuser National Park, North Sumatra, and has been conserved at the Bogor Botanical Garden since 1994. This study aims to characterize the micromorphology and DNA profile D. macrantha using DNA barcoding with rbcL and ITS gene markers. Sample of D. macrantha were collected from the Bogor Botanical Gardens for analysis. Micromorphological analysis revealed that the leaves exhibit three vein types (primary, secondary, and tertiary) with a pentagonal venation pattern and a tri-veinlet veinlet pattern. Additionally, eight types of trichomes were observed on the abaxial surface. Molecular characterization showed that the rbcL sequence was 563 bp long, with nucleotide composition T (27.9%), C (21.7%), A (27.9%), and G (22.6%). The ITS sequence was 960 bp long, with nucleotide composition T (15.4%), C (33.4%), A (19.0%), and G (32.2%). BLAST analysis of both rbcL and ITS genes revealed a high level of similarity between D. macrantha and D. zibethinus. This study provides fundamental data supporting the conservation and further research of D. macrantha, particularly in morphological and molecular aspects.

Morphological Characterization and In Vitro Culture Optimization of Purple-Fleshed Sweet Potato (Ipomoea batatas L. Poiret) Accessions

Muhamad Sabda, Clarencia Margareth — Thu, 26 Jun 2025 00:00:00 +0000

Purple-fleshed sweet potato (Ipomoea batatas L. Poiret) is a functional food crop known for its high anthocyanin content and nutritional value. This study aimed to characterize the morphological traits of stem and leaf organs from seven purple-fleshed sweet potato accessions and to evaluate the effectiveness of in vitro culture techniques for their conservation. Morphological traits were assessed using a standardized scoring system and analyzed using Principal Component Analysis (PCA) and cluster analysis. Results showed significant variation among accessions, with Ungu Lonjong appearing genetically distinct, while Ayamurasaki, KT Lampa, and Local NTT exhibited high similarity. In vitro culture analysis involved the sterilization and cultivation of explants on Murashige and Skoog (MS) medium and minimal growth medium. The highest sterilization success rate was observed in Ungu Lonjong (78.3%), whereas Local NTT showed the highest contamination. This study demonstrates the potential of combining morphological data and tissue culture for effective characterization, conservation, and future purple-fleshed sweet potato germplasm breeding.

Keywords: Ipomoea batatas, germplasm conservation, morphological characterization, tissue culture