Category Archives: Volume 36 No. 2 (2014)

Aerobic Rice Production System(ARPS): Improving Productivity and Profitability in Water-Scarce Areas of Bulacan

Authors: Dinah Marie C. Dayag1, Junel B. Soriano2, Josie A. Valdez1 and Gregory Moses Villacorta1


On-farm study on rice-based cropping system following recent water-saving technologies for rice production such as ARPS-ARPS, ARPS-alternate wetting and drying (AWD) and existing or Farmers’ Practice (FP) was conducted in a rainfed lowland area in Brgy. Mataas na Parang, San Ildefonso, Bulacan. Field experiments were conducted from June to November 2011 for the wet season and December 2011 to March 2012 for the dry season. Variety used for the ARPS and AWD was NSIc Rc192 and PSB Rc18 for FP. Yield and yield components of the three treatments showed no significant difference during WS. Significant higher number of tillers hill-1 was observed for ARPS-ARPS and ARPS-AWD compared to FP. No significant difference was observed for the yield and yield components during the dry season (DS) for ARPS-ARPS and ARPS-AWD. FP was not established during the DS because of the unavailability of water during the time. During WS, ARPS was the most appropriate cropping system since this intervention obtained higher water productivity and ROI when compared with the FP. During the dry season, AWD and ARPS were suitable to the rainfed lowland areas of Bulacan. Results of this study showed that aerobic rice production system for the rainfed lowland areas improved water and land productivity as well as increased annual rice production and farmers’ income most particularly in ARPS-AWD which consistently gave the highest net income of PhP 36,896.20, PhP 14,417.50 and PhP51,313.70 during the Wet Season, Dry Season and for the total two cropping seasons, respectively

Keywords: Aerobic rice production system, alternate wetting and drying, farmer’s practice, water productivity, cropping system, rice ecosystems

Annals of Tropical Research 36(2):190-199(2014)
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Climate Change Impacts on Livestock Production Systems: A Review

Author: Angie R. Poliquit


The socio-economic contribution of livestock production to global livelihood and food security offsets its negative effects on the environment through greenhouse gas (GHG) emission. Livestocks are emitters of GHGs, carbon dioxide (CO2) from land conversion and deforestation, nitrous oxide (N2O) from manure and slurry, and methane (CH4) from animal digestion which significantly contribute to climate change. Climate change has both direct and indirect impacts on animal farming. Thus, the main concern nowadays is toward the development of programs for adaptation and mitigation of GHG emissions. This review provides knowledge about climate change impacts on livestock production systems with the identification of strategies for livestock adaptation to climate change and mitigation of GHG emissions.

Keywords: climate change, livestock, greenhouse gas, emission, enteric fermentation, adaptation, mitigation

Annals of Tropical Research 36(2):148-189(2014)
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Morpho-physical and Chemical Characteristics of Strongly Weathered Soils in Silago, Southern Leyte, Philippines

Authors: Maria Katrina B. Piamonte, Victor B. Asio and Suzette B. Lina


The study evaluated the morpho-physical and chemical characteristics of strongly weathered soils in Silago, Southern Leyte, one of the biodiversity hotspots in the Philippines. Examination of seven soil profiles revealed that the soils have colors ranging from yellowish brown to yellowish red, have high clay content (37.04 to 62.15%), and moderate to high porosity values (38.49 to 52.83%). They are deep (>3m) and friable when moist but very plastic and very sticky when wet. In terms of soil chemistry, most of the soils have acidic pH values (<6.75), have low to moderate potential CEC (11.31 to 38.13 cmolc/kg), low to high base saturation (0.76 to 69.62%), and extremely low to medium organic matter content (0.07 to 2.59%). The soils contain low to medium N (0.01 to 0.28%), and extremely low available P (< 5 mg/kg). However, most of the soils contain sufficient amounts of exchangeable Mg (0.12 to 9.28 cmolc/kg), and Na (0.05 to 1.70 cmol/kg) except profile 5, but are deficient in Ca (0.07 to 0.27 cmolc/kg) and exchangeable K (0.02 to 0.37 cmolc/kg) since the soils are acidic. Most of the soils are classified as Hapludults (USDA Soil Taxonomy) or Haplic Alisols (WRB) except the one in the toeslope which is a Hapludalf or Haplic Luvisol. The study revealed that the soils have closely related properties probably due to their similar parent material, original forest vegetation and climate. The differences in some soil properties appear to be the effect of topography.

Annals of Tropical Research 36(2):115-147(2014)
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In vitro Antioxidant Potential of Fatty Acids Obtained by Direct Transmethylation from Fresh Cordia sebestena Flowers

Authors: Olubunmi Atolani, Oluwatimilehin O. Kayode, Oluwaseeni Adeniyi and Charles B. Adeosun


The determination of fatty acid profile of plant material is often attained via multistep procedures. Recent innovation has made it possible to obtain fatty acids from fresh matrix in a single step. This study was conducted to analyze the fatty acids present in C. sebestena using direct transmethylation in a one-step procedure with methanol:benzene: hexane:aluminium chloride:sulphuric acid (37:20:36:5:2 v/v) as transmethylation reagents and gas chromatography/mass spectrophotometry, GC-MS for quantification. The antioxidant potential of the transmethylation product was also evaluated using DPPH assay. GC-MS revealed the presence of seventeen fatty acids in C. sebestena. Palmitic acid (32.45%), myristic acid (21.49%), cis-oleic acid (9.57%), 13-octadecenoic acid (5.76%) and stearic acid (4.95%) were the major fatty acids while gondoic acid (0.88%) (an omega-9 fatty acid) and other 11 fatty acids (0.11 to 0.96%) constitute the minor components. Non-fatty acids compounds (17.43%) were also present in the obtained product. Yield (3.33% fresh weight) was modest and product had high antioxidant activity suggesting the viability of the method in determining the fatty acid profile of the plant. The procedure saves time and resources that are associated with conventional multistep method. Results obtained showed evidence that Cordia sebestena could be an attractive source of fatty acids that are important natural antioxidants.

Keywords: Antioxidant, Cordia sebestena, Essential fatty acid, FAMEs, GCMS, Transesterification

Annals of Tropical Research 36(2):104-114(2014)
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Extraction and Characterization of “Batuan” [Garcinia binucao (Blco.) Choisy] Seed Protein

Authors: Elizabeth S. Quevedo1, Marivic S. Lacsamana2 and Antonio C. Laurena3


“Batuan” [Garcinia binucao (Blco.) Choisy], an indigenous, lesser known member of the Gutifferae family with export potential is underutilized and understudied. The present study was carried out to extract and characterize the protein in “batuan” [Garcinia binucao (Blco.) Choisy] seeds for nutritional quality assessment. Protein content of “batuan” seed meal was 8.9 ± 0.59% dry basis. Solubility fractionation of “batuan” seed meal showed globulin and glutelin as the major seed proteins. SDS-PAGE resolved the globulin and glutelin into three groups of polypeptides with molecular weights of about 20 – 54 kDa. Amino acid analysis revealed that seed protein contained all the essential amino acids with leucine as the most abundant while tryptophan, the least. “Batuan” seed proteins were mostly made up of acidic and hydrophobic amino acids with glutamic acid (2.67%) as the highest. Nutritional assessments including E/T (38.4%), amino acid score (1.6%), predicted PER (3.2-3.7) and estimated BV (98.3%) suggested that the seed proteins are of good quality. Hence, “batuan” seeds has a promising potential as an important sources of valuable proteins and amino acids for use as food supplement/enhancing ingredient.

Keywords: amino acid, “batuan” seed protein, nutritional, tryptophan

Annals of Tropical Research 36(2):89-103(2014)
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Use of Information and Communication Technologies in Natural Calamities by Residents in a Flood-Prone Community: A Case in Leyte, Philippines

Authors: Ma. Victoria Stephane G. Asio and Editha G. Cagasan


Residents in disaster-prone areas use information and communication technologies (ICTs) to cope with risks. This study was conducted in a flood prone barangay of Palo, Leyte to determine the informants’ use of ICTs in natural calamities. Following the grounded theory approach, the 23 informants were chosen using snowball sampling and were interviewed using an in-depth interview guide. The theoretical model generated from the data showed that in this flood-prone community, residents are exposed to various information sources that they use in the different phases of the disaster for various reasons. Although informants’ reasons for accessing and using ICTs were not primarily related to their use in times of disasters, their good access to these technologies proved useful in times of calamities. ICTs have also proven as crucial means of communication especially in giving residents warnings of an incoming disaster and in surviving and recovering from the disaster. Results suggest the need to enhance ICT access among residents and officials in disaster-prone communities.

Keywords: Mobile phones, Disaster response, Risk Communication, Community communication

Annals of Tropical Research 36(2):63-88(2014)
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Behavioral Responses to Climate Information: A Case of Small Scale Rice Farmers in Vulnerable Communities in Leyte, Philippines

Authors: Rotacio S. Gravoso1, Remberto A. Patindol2 and Canesio D. Predo3


As in many developing countries, the advent of extreme climatic events, including El Niño and La Niña phenomena has exposed the livelihoods of small scale Filipino farmers to climate vulnerabilities. Recent developments in climate prediction suggest that seasonal climate forecasts (SCF) have potentials for alleviating the vulnerability of farmers’ livelihoods. In the Philippines, however, farmers’ uptake of SCF is low. This study pilot-tested SCF dissemination and examined if small rice farmers from communities vulnerable to flooding and drought would use the information in their farming and management decisions. Farmers then participated in a seminar on the basic concepts of climate and were advised of the climate forecast for the July 2012 cropping season. Focus group discussions were conducted four months after, that is, during the harvest season. Respondents assessed the SCF as “accurate” but in making farm decisions, they relied on their experiences on the onset and amount of rain. For some farmers, the shortage of rainfall in the middle of the cropping season led to crop failure. Thus, they resorted to growing other crops. Results of this study highlighted the need to inform farmers of the onset, amount, and duration and distribution of rainfall for the incoming cropping season. Overall results indicate the need for the meteorological agency to improve the skill and to down-scale (localize) the climate forecast.

Keywords: Climate change risk, climate change adaptation, seasonal climate forecast, forecast skill

Annals of Tropical Research 36(2):45-62(2014)
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Factors Contributing to the Decline of the Anchovy Fisheries in Krueng Raya Bay, Aceh, Indonesia

Authors: Zulhamsyah Imran1,2 and Masahiro Yamao1


Anchovy fisheries in Indonesia faces an imminent collapse in the next decade. This research explores some crucial factors contributing to the overfishing or depletion of anchovy resources. It was conducted in Krueng Raya Bay during September – October 2012. Survey, focus group discussion and interviews were implemented to explore the state of anchovy and coastal ecosystem degradation. It was shown that 52% of the total production was caught by lift net boats during the west monsoon season of 2012. Simple regression analysis resulted to different models of MSY either before or after the tsunami in 2004 which were shown as y = 0.8696 – 0.00008x and y = 0.1138 – 0.00002x, respectively. Model 1 recommended reducing the number of lift net boat to 43 units for optimization of yield. On the other hand, Model 2 suggested that only 23 units could be operated for optimal effort each year. Average recent catch in MSY showed 53.9% (less abundant) before the tsunami and 5.5% (depletion) after that. These conditions was led by increasing effort, un-friendly, destructive fishing gears, and degradation of coral reef and mangrove. Such a tragedy was accelerated by anthropogenic factors and compounded by the tsunami factor. The tsunami impact on anchovy fishery depletion may be lesser than the combined effects of destructive fishing and anthropogenic factors.

Keywords: Anchovy fisheries, factors contributing, maximum sustainable yield, anchovy depletion

Annals of Tropical Research 36(2):23-44(2014)
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Role of Secondary Metabolites and Radical Scavenging Aptitude for Better Adaptability of Mangroves in Varying Salinity of Sundarbans, India

Authors: Nirjhar Dasgupta1,2 , Chandan Sengupta2 and Sauren Das1


Comparative adaptability in five halophytes (Bruguiera gymnorrhiza, Excoecaria agallocha, Heritiera fomes, Phoenix paludosa and Xylocarpus granatum, of which, H. fomes and X. granatum presently are stressed in Sundarbans area) were evaluated with respect to occurrence of total phenol, flavonoids, and radical scavenging ability following ABTS [2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)], DPPH (1, 1-diphenyl-2-picrylhydrazyl) assay and Fe2+ chelating ability.
Amount of total phenol (TP) and flavonoids (TF) were much higher in all taxa grown in Sundarbans than those of mesophytic one. TP and TF were significantly augmented as the substrate salinity increased in B. gymnorrhiza, E. agallocha and P. paludosa but disordered in H. fomes and X. granatum, where increment occurred only up to a certain salinity level. Percent of free radical scavenging of extractants by DPPH and ABTS radical perceived significant correlation with salinity in former three but differ in H. fomes and X. granatum. Ferrous ion chelating ability also showed the similar trend.
Owing to polyphenols occurrence and ROS scavengers, the present work clearly indicates the better adaptability of B. gymnorrhiza, E. agallocha and P. paludosa in elevated substrate salinity than those of the other two. Lower ROS scavenging ability of H. fomes and X. granatum also points to their perilous occurrence in elevated saline zones.

Keywords: Flavonoids; Phenols; ABTS; DPPH; Fe2+ chelation; mangroves; Sundarbans

Annals of Tropical Research 36(2):1-22(2014)
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