JERAFF - Linker (The Journal of Emerging Research in Agriculture, Fisheries and Forestry)

Quantification of Nitrous Oxide, Methane, and Carbon Dioxide Emissions from Agricultural Machineries in Cagayan Valley Rice Farming Systems

Sarah Aquino — 2025-12-29

Rice cultivation in Cagayan Valley is one of the major sources of greenhouse gas (GHG) emissions, having 80.61 Gg of methane (CH?) emission in 2021 from irrigated and rainfed fields (Aquino and Galamgam, 2025) yet emissions from agricultural machineries remain poorly quantified despite rising mechanization levels.

This study quantified nitrous oxide (N?O), methane (CH?), and carbon dioxide (CO?) emissions from key agricultural machineries used in rice farming systems across the region. Fuel consumption and machinery data were obtained from the Department of Agriculture – Regional Agricultural Engineering Division (DA-RAED). Emissions were estimated using the IPCC Inventory Software (2006 Guidelines, Tier 1 and Tier 2 methodologies), with disaggregation by gas type, machinery type, and province.

Results showed that Four-Wheel Drive Tractors (4WDT) and Rice Combine Harvesters (RC) contributed 64.7% and 33.8% of total emissions, respectively, while rice seeders and transplanters accounted for less than 1.5% combined. Isabela and Cagayan emerged as the highest provincial emitters due to extensive mechanization. Findings highlight the trade-off between productivity gains and increasing carbon footprint in mechanized rice farming.
This study recommends targeted interventions in high-consumption provinces, promoting fuel-efficient technologies, low-emission machinery, and renewable energy integration to achieve climate-smart mechanization. Results provide baseline data to support regional climate policies, DA mechanization programs, and the Philippines’ commitments under the Paris Agreement.

Whispered Bidding Practice (Bulungan) in the Mercedes Fish Port: Cultural Communication and Informal Economy in Philippine Fisheries

Melanie D. Bacuno — 2025-12-31

This study investigates bulungan (a whispered bidding practice) at the Mercedes Fish Port in Camarines Norte, Philippines, as both a cultural communication system and an informal economic mechanism. The fisheries sector is vital to the Philippine economy, yet many trade practices operate outside formal structures. Bulungan is one of these practices, sustained by trust, secrecy, and reciprocity among fisherfolk, brokers, and buyers. The study used a qualitative case study design. Data were collected through focus group discussions, observations, and audio-visual documentation of the process. Thematic analysis was guided by communication models, including Shannon and Weaver's linear model and Barnlund's transactional model, as well as theories of cultural communication and the informal economy. Findings show that bulungan works as a structured communication cycle where participants shift roles as senders, receivers, and feedback providers. It conveys cultural meanings such as fairness, discretion, and trust, and it performs communicative functions like regulating prices, avoiding conflict, and keeping order in a noisy marketplace. Economically, it provides a grassroots system of trade that supports livelihoods when formal regulations are limited. The practice faces challenges such as oversupply, price disputes, and cheating (dayaan), which create noise in the communication process. However, it adapts through trust-based relationships and alternative methods, as seen during the COVID-19 pandemic. The study concludes that bulungan is more than a trade practice. It is an intangible cultural heritage that expresses community values while ensuring economic resilience. Recommendations stress the role of development communication in documenting and preserving bulungan, while also integrating it into fisheries governance to create more inclusive and culturally grounded policies.

Effects of Combined Fermented Sheep Manure and Plant Juice on Cucumber Growth, Yield, and Return on Investment

Alvin Ramos — 2025-12-29

Organic inputs such as fermented manures and plant extracts are increasingly explored as alternatives to synthetic fertilizers. This study evaluated the effects of fermented sheep manure and fermented plant juice on cucumber (Cucumis sativus) growth and productivity at the Agri-Tech Eco Tourism Farm, Isabela State University–Roxas Campus. A Randomized Complete Block Design (RCBD) with five treatments was used: 100% recommended fertilizer (control) and four combinations of 50% recommended fertilizer plus varying levels of fermented sheep manure (500–650?ml) with a constant dose of fermented plant juice. The growth and yield parameters measured included fruit number per plant, fruit length and diameter, and weight of marketable and non-marketable fruits. Results showed that while cucumber growth was comparable across treatments at 15 and 30 days after sowing, significant differences were observed at 45 days. The control (T1) produced the heaviest and most numerous marketable fruits, the lowest proportion of non-marketable fruits, and the highest total yield, resulting in a return on investment (ROI) of 94.81%, which was higher than all organic input combinations. Fermented sheep manure and plant juice supported growth and yield but did not surpass the productivity or profitability of full synthetic fertilization. These findings highlight that, under the conditions of this study, the control treatment provided the highest ROI, quantifying the economic advantage of the recommended fertilizer rate.

Comparative Yield Performance of Hybrid Eggplant (Solanum melongena) Using Vermicast Produced by Different Earthworm Species

Dominic Rodriguez — 2025-12-29

The study aimed to determine the performance of the vermicast produced from the three surface-dwelling earthworms, Cross Bred Earthworm, African Night Crawler (Eudrilus eugeniae), and Native Earthworm (Perionyx excavatus), on the yield of hybrid eggplant. The study was conducted at the Central Experiment Station of the Department of Research and Development of the Isabela State University-Cabagan Campus. It is envisioned to encourage farmers in producing their own fertilizer through vermicomposting and using pure organic fertilizer instead of being dependent on inorganic fertilizer. This study evaluated the use of pure organic fertilizer on the production of hybrid eggplant, particularly the variety Morena. Treatments used are the result of the nutrient analysis of the five treatments from vermicomposting, particularly the Nitrogen, Phosphorus, and Potassium (NPK), namely: T1 – 0.61-0.13-0.40, T2 -0.48-0.18-0.36, T3- 0.51-0.15-0.37, T4 – 0.60-0.11-0.42, and T5 – 0.59-0.17-0.43. The result of the study revealed that T2 has the highest yield with an average weight of 5.53 t/ha, followed by T5 with 5.49 t/ha. T1 with 4.41 t/ha, T3 with 4.27 t/ha, and T4 has the lowest yield with a mean weight of 4.10 t/ha. Among the five treatments, T2 has the highest return on investment (ROI) with 314%, followed by T5 with 311% and T1-230%, T3-220%, and T4-207%, respectively. This study showed that vermicast was still productive when used in a hybrid variety of eggplant compared to the usual use of either balanced fertilization or pure inorganic fertilizer, which has more or less the same productivity.

Effect of Microbial Ratio, Storage Temperature, and Packaging on the Viability and Stability of Co-Inoculated Rhizobium tropici and Azospirillum spp. in Nitrogen-Fixing Biofertilizer

Sarah Aquino — 2025-12-29

The privatization of Bio-N biofertilizer in the Philippines created an urgent need for locally produced and cost-effective alternatives. In response, the Department of Agriculture–Ilagan Soil Laboratory (DA-ISL) developed a dual-strain biofertilizer by co-formulating Rhizobium tropici, isolated from wild tallgrass (Saccharum spontaneum), with Azospirillum spp., a well-established nitrogen-fixing bacterium. This study aimed to assess the long-term viability and stability of co-inoculated formulations under varying microbial ratios, packaging types, and storage conditions.

An experimental research design was employed, testing five mixtures of R. tropici and Azospirillum spp. stored for 12 months under ambient (28–32 °C) and air-conditioned (20–25 °C) conditions. Viability was assessed monthly using serial dilution and spread plate techniques, with colony-forming units (CFU/g) analyzed to determine formulation and storage performance.

Results showed that microbial populations typically stabilized or increased in the first two to three months before gradually declining. Among all treatments, Mixture A (50% R. tropici + 50% Azospirillum spp.) packaged in aluminum foil and stored under air-conditioned conditions demonstrated the highest stability, maintaining 2.6 × 10? CFU/g at Month 12. In contrast, R. tropici–dominant mixtures exhibited sharper viability losses, while Azospirillum alone remained more resilient. Packaging and storage temperature emerged as critical factors influencing shelf life.

These findings highlight the potential of co-inoculated biofertilizer as farmer-ready product. Balanced microbial ratios, protective foil packaging, and cool storage can ensure product reliability, reduce dependence on commercial inoculants, and strengthen farmer adoption of sustainable soil fertility practices. Future research should validate field performance, assess cost-effectiveness, and explore alternative carriers to support large-scale adoption and farmer use.

Development of Production Protocols for Local Sesame Varieties in a Tropical Agro-Ecological Setting

Vilma Atalin — 2025-12-29

Sesame (Sesamum indicum L.) is an ancient oilseed crop valued worldwide for its high?quality edible oil and protein. In the Philippines, sesame remains a minor crop compared to staples like rice and corn, despite its potential to enhance farmer livelihoods and nutrition. Expanding local sesame production could reduce dependence on imports, diversify income sources, and provide healthier oil alternatives for consumers. Productivity, however, is constrained by limited adoption of improved agronomic practices and a lack of varietal evaluation under local conditions. Addressing these challenges through research on fertilizer management and varietal performance across seasonal environments is essential to unlock sesame’s potential as a profitable and sustainable crop. This study assessed sesame growth and yield under varying fertilizer treatments across wet and dry seasons (2022–2023). Results showed that the FT2 treatment (60-60-60 NPK/ha) + 10 bags organic fertilizer/ha) consistently produced the highest seed yield in both seasons (352.58 kg/ha in wet; 200.67 kg/ha in dry), along with superior capsule and seed counts. Among the tested varieties, black sesame (V2) outperformed brown sesame (V1), recording a significantly higher mean seed yield (321 kg/ha vs. 281 kg/ha). Although fertilizer rates did not significantly affect plant height, brown sesame produced taller plants. Findings highlight the benefits of organic fertilizer supplementation and the profitability of black sesame. Beyond supporting SDG 2 (Zero Hunger), this research demonstrates practical strategies for resilient cropping systems, reduced reliance on imports, and sustainable farmer incomes in the Philippines.

Microscopic Investigation and Identification of Mitotic Stages Using Onion (Allium cepa) and Onion Spring (Allium fistulosum)

Mary Grace Hista — 2025-12-29

Mitosis is a fundamental process in plant growth and development because it governs the production of new cells in meristematic tissues. Examining its stages provides insights into genetic stability and cellular behavior, which are relevant to agriculture, crop improvement, and environmental monitoring. Although cytological studies using Allium species are well established, there is continued value in demonstrating how classical staining methods, such as acetocarmine, effectively visualize mitotic events in educational and basic laboratory settings. This study aimed to identify and describe the stages of mitosis in onion (Allium cepa) and spring onion (Allium fistulosum) root tips using acetocarmine-stained squash preparations. Fresh root tips were hydrolyzed in hydrochloric acid, stained with acetocarmine, and examined under a compound light microscope. The observed mitotic stages were documented based on chromatin morphology and nuclear characteristics. Both species exhibited similar observable mitotic features under the staining and microscopic conditions used, with clear visualization of prophase, metaphase, and telophase, identified by chromatin condensation, chromosome alignment, and nuclear reformation, respectively. Anaphase was not observed, likely due to its brief duration relative to the other phases. Overall, the results demonstrate that acetocarmine staining provides reliable visualization of major mitotic stages, although it lacks sufficient resolution to distinguish individual chromosomes. These findings confirm that simple cytological techniques remain effective tools for demonstrating mitosis in instructional and introductory research contexts. Future studies may employ DNA-specific stains, digital imaging, and larger sample sizes to capture short-lived stages and enable quantitative analysis.

Comparative Evaluation of Black and Brown Sesame (Sesamum indicum L.) Varieties in the Development of Novel Food Products

Vilma Atalin — 2025-12-29

Sesame (Sesamum indicum L.) is a nutrient-rich oilseed crop with recognized health benefits, yet its utilization in innovative food products remains limited. This study aimed to develop sesame-based products and assess their microbial safety and consumer acceptance. Black and brown sesame varieties were processed into three products: sesame butter, sesame brittle, and sesame polvoron. Microbial testing was conducted at the Department of Science & Technology–Regional Standards and Testing Laboratory to ensure food safety, followed by a single-blind sensory evaluation with 75 respondents using a nine-point hedonic scale. Brown sesame butter demonstrated the highest overall acceptance, particularly in terms of taste and aroma, outperforming both Black sesame butter and the commercial control. For sesame brittle, only the brown variety passed microbial testing. While the commercial control was generally preferred, the brown brittle scored comparably in terms of aroma and texture. In contrast, only black sesame polvoron met microbial safety standards, but it was consistently rated lower than the control across sensory attributes. Results indicate that consumer acceptance varied by product and sesame variety, with brown sesame being generally preferred for butter and brittle, and black sesame being viable only for polvoron. The study highlights the pivotal role of microbial safety and sensory attributes (taste, texture, aroma, and above all, visual appeal) in the evaluation of consumer acceptance. As such, the results indicate that sesame seeds have good potential for product innovation, although their successful commercialization relies on the convergence of product level with customer perception.