Category Archives: Volume 29 No. 1 (2007)

Amplification of health risk messages in leading Philippine newspapers

Author(s): Jedess Miladel C. Nuñez and Rotacio S. Gravoso


This study aimed to find out the coverage and amplification of health risk messages of leading Philippine newspapers: Philippine Daily Inquirer, The Philippine Star, and Manila Bulletin. Data were gathered through a content analysis of health risk articles published by those newspapers in 2005.
Results revealed that the health risk articles published in 2005 by the three newspapers focused on bird flu, dengue fever, food poisoning and meningococcemia. However, the three newspapers did not give prominence to health risk articles. In terms of sources of information, most of the articles quoted experts and government officials but were prompted by public experiences. Most of the articles assigned blame or responsibility to organizations rather than individuals.
The lexical content analysis using the Language Inquiry and Word Count (LIWC) showed that negative emotion words, words linked to people’s ratings of anxiety, were present in health risk articles, indicating intensification of the health risk. For bird flu articles, most of the negative words were in the pre-peak and post-peak periods, while for dengue fever, in the peak period. For food poisoning and meningococcemia, most negative emotion words in the articles were published during the post-peak period.

Keywords : health risk messages, risk amplification, risk intensification, negative emotion words, Philippine newspapers, content analysis

Annals of Tropical Research 29(1):90-103(2007)

Chemical dynamics of a highly weathered soil under native tree species in Mt. Pangasugan, Leyte

Author(s): Juvia P. Sueta, Victor B. Asio, and Anabella B. Tulin


The study evaluated the changes of the chemical properties of a highly weathered soil planted to native tree species. Soil samples were gathered at monthly interval for 12 months and were analyzed for pH, OM, N, P, Ca and Mg. Decomposition of leaf litter of the dominant native tree species (Parashorea malaanonan and Dipterocarpus warburgii) in the site was determined using the litter bag method.
Results revealed significant temporal variations of pH in CaCl2, OM, total N and available P, but not for pH in H2O and exchangeable Ca and Mg. Significant differences between sites (spatial variation) were also observed for OM, total N and exchangeable Ca and Mg suggesting the important effects of vegetation type on these soil properties. Decomposition rates of 0.0331 kg/ha/week and 0.0231 kg/ha/week were obtained for D. warburgii and P. malaanonan, respectively. Both rates suggest fast litter decomposition.

Keywords : Research productivity; DevCom approaches; DevCom domains

Annals of Tropical Research 29(1):73-89(2007)

Survey and evaluation of promising mycoherbicides for the control of asyang [Mikania cordata (Burm.F.) B. L. Robinson]

Author(s): Lualhati M. Noriel, Yolanda C. Mangaoang, Rodolfo A. Paningbatan, Elizabeth P. Parac, and
Rowena V. Salva


The study surveyed and collected diseased specimens of asyang [Mikania cordata (Burm. F.) B. L. Robinson] from various places of Leyte and Southern Leyte; isolated and identified the promising fungal pathogens (technically known as mycoherbicide) for the control of asyang; and determined the host range of the promising mycoherbicides.
Seventeen fungal isolates were found pathogenic to asyang with 4-9 days incubation period. The isolates from the towns of Capoocan (Cap), Matalom (Mat-2) and Tomas Oppus (TO) consistently caused significantly higher number of lesions per square leaf centimeter of leaf surface causing early death of leaves than the other isolates. Based on lesion and conidial characteristics, Cap isolate was identified as Cercospora mikaniacola Stevens while Mat-2 and TO isolates as Curvularia pallescens Ellis. Moreover, the promising isolates were also found non-pathogenic to different host plants tested.

Keywords : asyang, Mikania cordata, biological weed control, Cercospora mikaniacola, Curvularia pallescens, mycoherbicides

Annals of Tropical Research 29(1):63-72(2007)

Reaction of abaca (Musa textilis Nee.) accessions and varieties to fusarium wilt caused by Fusarium oxysporum f.sp. cubense (E.F. Smith) Snyd. and Hans.

Author(s): Lucia M. Borines, Elsie E. Salamat, and Rammel B. Cardines


Fusarium wilt caused by Fusarium oxysporum f.sp. cubense (FOC) is one of the problem diseases attacking abaca. The most effective way of minimizing the damage is through the use of resistant varieties. The levels of resistance of different abaca varieties/accessions, however, have not been determined yet so this study was conducted to: 1) evaluate the reaction of eight recommended abaca varieties to fusarium wilt, 2) evaluate the reaction of abaca varieties/accessions and abaca relatives from the National Abaca Research Center (NARC) germplasm collection and production area to fusarium wilt, and 3) confirm the reaction of the identified resistant varieties/accessions in a naturally infested field.
Among the 8 recommended abaca varieties, Linino showed resistance to FOC having the lowest infection, foliage yellowing and internal vascular discoloration ratings in a pot experiment. This variety was also proven resistant in the field plot screening together with 6 other accessions, namely: Alman No.2, Alman No.4, Tinawagan Puti #.2, Pakol, CES x Pacol and Pakil #1. Of the six, Alman No.4, Tinawagan Puti #2, Linino and Pakil also showed resistance to FOC, when planted in a naturally infested field in Polahongon, Mahaplag, Leyte.

Keywords : abaca, germplasm, resistance, fusarium wilt

Annals of Tropical Research 29(1):43-62(2007)

Forest carbon stock and livelihood opportunities under the CBFM Project in Midwestern Leyte Province, Philippines

Author: Arturo E. Pasa


The study assessed the carbon stocks or storage within the Community-Based Forest Management (CBFM) Project in Midwestern Leyte Province. The CBFM project area stored an average carbon density of 333 Mg/ha from aboveground biomass down to the soil complex (0-1m depth). The upperstorey biomass had an average carbon density of 166 Mg/ha while 1.94 Mg/ha for the understorey biomass. In addition, floor litter carbon density ranged from 1.38 Mg/ha to 2.75 Mg/ha, root carbon density from 11.0 to 17.4, and soil carbon density from 111 to 221 Mg/ha.
The huge amount of carbon stored under the CBFM project is a potential livelihood opportunity for the local people. Several organizations are interested in carbon offset projects where huge amount of fund is involved — a situation where both farmers and the environment would be benefited.

Keywords : environmental services, forest carbon, rewards, livelihood opportunities, CBFM Project

Annals of Tropical Research 29(1):26-42(2007)

Tomato fruit parthenocarpy and yield increase in response to chlorophenoxyacetic acid

Author(s): Rosalina D. Poliquit1 and Misael T. Diputado, Jr.2


An experiment was conducted to evaluate the influence of rate and time of application of chlorophenoxyacetic acid (CPA) on the fruit set, yield and quality of tomato (variety, Improved Pope) The application of CPA enhanced fruit set, reduced the number of days to fruit maturity and consequently increased the yield and yield components of tomato. The optimum concentration of the chemical was 75 pm. It was more effective when applied during anthesis than one week after anthesis.
CPA application regardless of concentration caused the production of parthenocarpic fruits. It did not significantly affect fruit quality in terms of peel color development, firmness, visual quality rating and weight loss.

Keywords : chlorophenoxyacetic acid, fruit set, plant growth regulator, parthenocarpy, tomato

Annals of Tropical Research 29(1):14-25(2007)

In vitro culture of rose species (Rosa spp.) via axillary bud growth

Author(s): Zosimo S. de la Rosa, Jr. and Marilyn M. Belarmino


The utilization of nodal stem cuttings containing dormant axillary buds as explants for plant production of two rose species; Rosa chinensis cv.‘Old Blush’ and R. centifolia cv. ‘Petite de Hollande’ was demonstrated in this study. This propagation technique required the breaking of dormant axillary buds by aseptically culturing them in agarsolidified Woody Plant Medium (WPM) added with 0.5, 1.0, and 2.0 mg l-1 of 6benzylaminopurine (BAP) or, a combination of 2.0 mg l-1 BAP and 0.01 mg l-1 naphthalene acetic acid (NAA). Production of multiple adventitious shoots from one nodal stem explant was obtained after three months of culture in medium supplemented with 1.0 or 2.0 mg l-1 BAP. Four types of plant morphology; single shoot (type 1), multiple shoots with normal leaves (type 2), cluster of tiny shoots with curly leaves (type 3), and single shoot with callus at the base (type 4) were observed from the axillary bud-derived plantlets. The rooting of plantlets was induced in WPM containing 0.25 to 1.0 mg l-1 of indole-butyric acid (IBA) or, 2.0 mg l-1 of indole-3-acetic acid (IAA).

Keywords : benzylamino purine, naphthalene acetic acid, nodal stem, woody plant medium

Annals of Tropical Research 29(1):1-13(2007)