Category Archives: Volume 31 No. 2 (2009)

Conditions leading to addiction and avoidance of massively multiplayer online role playing games (MMORPGs) among game addicts

Author(s): Neil Anthony C. Rusia and Rotacio S. Gravoso


Interviews with 23 massively multiplayer online role-playing games (MMORPGs) addicts revealed that they were addicted to the games because they lacked worthwhile activities, MMORPGs offer online game features and deep online experience, they were interested in technological trends and gained personal satisfaction from playing MMORPGs, and due to their exposure to the game through the mass media, peers and relatives. Respondents said that playing MMORPGs is advantageous because it recreational entertaining; enhances interaction and socialization among peers and new acquaintances; promotes knowledge and improves players’ computer skills; neutralizes mood and relieves stress; serves as an escape from problems; improves self-confidence and develops self-expression; enhances trading skills and provides business opportunities; improves English communication skills; provides bragging rights among gamers; and it provides deeper online experience. However, MMORPGs are disadvantageous because they negatively affect gamers’ health, academic performance and analytical skills, relationship with peers, friends and family; these games expose them to deceit, distrust, cheating and sham; leads to financial setback; and develops negative personality among players.
Respondents said that they quit playing due to the monotony and software flaws of the MMORPGs and the games’ financial, time and health effects. Other reasons cited were their diversion of their attention to other activities and influence of people they consider significant to them. To quit playing, respondents re oriented their priorities, diverted their attention, sought guidance from significant others, and set themselves to quit the game. When they quit MMORPGs, they felt that they were able to improve management of their finances, became mature, and improved their academic performance, family and peer relationship, and health conditions.

Keywords : Computer games, addiction, students

Annals of Tropical Research 31(2):120-147(2009)

Improvement of the growth, yield, and tuber quality of purple yam through macro and micronutrient fertilization

Author: Anabella B. Tulin


The high demand for yam as food and for industry calls for the development of new technologies and innovations that will increase yam production. This study was conducted to assess the effects of the addition of different levels of micronutrient fertilizers (Biozome-200 micronutrient soil conditioner) to NPK fertilizers on the growth and yield of purple yam. Seven sets of experiments were conducted in six years employing different fertilizer treatments representing five levels of inputs. Purple yam (VU – 2 variety) was used as planting materials and these were planted at a distance of 1m x 50cm at a depth of 10cm.
of NPK fertilizers produced significantly bigger yams and higher plant biomass as compared to the unfertilized plots and those applied with NPK fertilizers only. Total tuber yields ranging from 15 tons to 26 tons/ha was obtained through the application of 150-50-150 kg/ha N – P2O5 – K2O + 4 to 16 kg/ha Biozome-200 using 100 gm tuber setts as planting materials. In terms of tuber quality, plant tissue analysis of tubers showed that purple yams that were fertilized with macro and micronutrients have higher amounts of total N, K, Zn, Ca, Mg, Fe, Mn, and Cu as compared to the unfertilized plants. These results implied the improvement of the nutritional content of purple yam tubers with macro and micronutrient addition.

Keywords : purple yam, macronutrients, micronutrients, yield, income.

Annals of Tropical Research 31(2):95-119(2009)

A review of soil degradation in the Philippines

Author(s): Victor B. Asio1, Reinhold Jahn2, Federico O. Perez3, Ian A. Navarrete4 and Sergio M. Abit Jr.1


The paper reviews the available information on soil degradation which is a major agricultural and environmental problem in the Philippines. Soil erosion appears to be the most widespread process of soil degradation and is also the most studied. Other important but less studied soil degradation processes include loss of nutrients and organic matter, salinization, acidification, pollution, compaction, and subsidence. Studies reviewed have shown that the widespread degraded upland soils possess chemical and physical constraints for crop growth like acidic or calcareous chemical condition, low organic matter and nutrient contents, shallow solum, presence of toxic substances and compaction. There is a need for more data on the physical and socio-economic characteristics of degraded lands to aid in the formulation of appropriate soil management strategies to support biodiesel production in these unproductive lands which is now being promoted by the Philippine government.

Keywords : Degraded uplands, land use change, soil degradation, soil erosion, tropical soils

Annals of Tropical Research 31(2):69-94(2009)

Impacts of the Techno Gabay Program in Eastern Visayas, Philippines as revealed by stakeholders’ stories of significant change

Author(s): Editha G. Cagasan1 and Ma. Theresa H. Velasco2


Monitoring of the impacts of the Techno Gabay Program (TGP) using the most significant change (MSC) technique was done for one year in nine Techno Gabay (TG) centers in Eastern Visayas, Philippines. Field technicians of the TG centers were trained on how to collect and select ‘stories of change’ from the TGP clients and other stakeholders. The collected stories were analyzed to determine the themes of the reported changes. The levels to which the reported changes correspond were determined using Bennett’s hierarchy of program outcomes as a guide.
A total of 80 stories were collected. These were about improvements in the field technicians’ extension delivery capability, changes in the program beneficiaries’ lives, improvements in stakeholders’ knowledge, attitudes and skills and about other changes. Analysis of the MSC stories revealed that the TGP was able to cause changes corresponding to higher levels of Bennett’s hierarchy of program outcomes. This suggests that the TGP was already able to have an impact on the knowledge, attitudes, skills, behavior, and the economic and social conditions of the program stakeholders.

Keywords : Monitoring and evaluation, story approach, stories of change, communication for development program

Annals of Tropical Research 31(2):41-68(2009)

Sweetpotato weevil pheromones and their precursors: Dose-response and structure-activity relationship in Cylas formicarius Fabr., Cylas brunneus Olivier and Cylas puncticollis Boheman

Author(s): Erlinda A. Vasquez1,2,5, Dietmar Schmidt2, Claus Peter Zebitz1, Uwe Beifuss2, Iris Klaiber2, Jurgen Kroschel3
and Remberto Patindol4


Structure-activity and species specificity of the three synthetic sweetpotato weevil pheromones, (Z)-3-dodecenyl-(E)-2-butenoate of C. formicarius, dodecyl-(E)-2butenoate of C. brunneus and decyl-(E)-2-butenoate C. puncticollis and their corresponding precursor free alcohols and trans-crotonic acid were assayed on virgin males of the three weevil species in the laboratory using one-arm olfactometer with bidirectional airflow. Each of the sex pheromones was specific to its conspecific males, however, a pheromone of a particular species may become active to another species only at higher amount to elicit the same degree of response. The free alcohol precursor of the pheromone of C. formicarius, 3-Z- dodecen-1-ol, showed sexual stimulation on C. brunneus and C. puncticollis while dodecan-1-ol functioned as an aggregation compound. The decan-1-ol, precursor of C. puncticollis pheromone, had the lowest attraction index regardless of weevil species tested. Males of C. formicarius and C. brunneus exposed to trans-crotonic acid performed a complete series of mating behavior

Keywords : Cylas formicarius, Cylas brunneus, Cylas puncticollis, female sex pheromones, crotonic acid, olfactometer assay, pheromone gland, chemical profile, GC-MS

Annals of Tropical Research 31(2):16-40(2009)

Callus induction and plant regeneration of two Cuban rice cultivars using different seed explants and amino acid supplements

Author(s): Maylin Pérez-Bernal , Magalis Delgado Rigo, Carlos Alberto Hernández Díaz, María Teresa Barceló Ávila and
Raúl Armas Ramos


Most of Cuban rice cultivars are classified into indica subspecies, and they are inclined to poor in vitro response. In this paper we studied the role of endosperm and amino acids on callus formation of two Cuban rice cultivars: J-104 and IACuba-28. Callus cultures were initiated from three treatments for mature seed: intact seed, embryo with scutellum but without endosperm, and endosperm alone. It demonstrated the direct incidence of endosperm on in vitro seed contamination. But the higher percentage of embryogenic calli was obtained from intact seeds, despite of 12.94 % of seed contamination. Callus formation from endosperm alone did not occur. The role of endosperm to successful callus formation from scutellum was discussed. Effect of amino acids on rice callus growth from intact seeds was examined by supplying callus formation medium with glutamine and proline, separately or in combination, in both cultivars. Callus formation of J-104 was improved considerably with 500 mg/l of proline and glutamine in the culture medium, but in IACuba-28 were not observed significant changes. The percentage of embryogenic callus and the increase of fresh weight of calli were correlated with genotype and amino acid supplement in culture medium.

Keywords : Endosperm, embryogenic calli, genotype, glutamine, proline

Annals of Tropical Research 31(2):1-15(2009)