The high acidity of‘Summer Queen’passionfruit (Passiflora edulis × P. edulis f. flavicarpa) in the winter season lowers the taste and affects the acceptability to consumers. The present study was conducted to determine whether a high temperature regime and a high soil moisture level could improve the fruit quality by reducing the acidity in the winter season. Potted plants were grown in three different greenhouses where the maximum/minimum temperatures were 27.3/20.7°C (high), 25.3/19.4°C (medium), and 24.0/16.3°C (low) combined with three different soil moisture levels: high (around 18%), moderate (around 13%) and low (around 7%) by the application of irrigation at different intervals in a plastic house located at Ishigaki, Okinawa, Japan, to examine the fruit acidity at maturity in winter. The acid content was the highest under low temperature conditions combined with a low soil moisture level, and the lowest at a high temperature combined with a high soil moisture level. Since a high temperature accelerated fruit development, the peak of the acid content was observed at 50-55 days after pollination (DAP), while at 60-65 DAP under medium and low temperature regimes. Low soil moisture level delayed the peak of fruit acidity by 5 days irrespective of the temperature regimes. The number of days required to maturity were 60 to 75 DAP under high temperature conditions, 70 to 85 DAP under medium and low temperature conditions. Citric acid was the main organic acid in the juice of‘Summer Queen’passionfruit and the titratable acidity was correlated with the content of citric acid.

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To obtain a sustainable supply of rootstocks, Taiwan native strain of mango (Mangifera indica L.) was propagated by cuttings, using discarded shoots from young seedlings as rootstocks for grafting. Short cuttings (60 cm) were superior in rooting and root length to long cuttings (90 cm) . The use of cuttings with a non-lignified base resulted in a higher rooting percentage and length value, compared to that of cuttings with a lignified base. Auxin exerted a beneficial effect on rooting and on the number of roots, while it significantly decreased the number of shoots that sprouted. When the cuttings were treated with zinc (ZnSO₄ solution) in combination with auxin, rooting was enhanced and a positive interaction was found in the number of roots generated. A combination of NAA 1000 mgL^-1 and ZnSO₄⋅7H₂O 1000 mgL^-1 resulted in optimum rooting (87.5%), while the application of NAA 1000 mgL^-1 and ZnSO₄⋅7H₂O 2000 mgL^-1 induced the largest number of roots (13.0) . This is the first report on the effectiveness of zinc treatment for cutting propagation of mango.

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Elephant foot yams (Amorphophallus paeoniifolius (Dennst.) Nicolson) usually produce inflorescences 3-4 years after planting. However, seed production under natural conditions is rare because inflorescences appear at low rates at random times. Therefore, flower induction is necessary for breeding programs. In order to clarify the effects of gibberellic acid (GA₃) and corm age on the floral induction of elephant foot yam, GA₃ was sprayed to dormant three-year-old (1386 g), two-year-old (671 g), and oneyear-old (131 g) corms at concentrations of 0, 1, and 2 g l^-1. Although the application of GA₃ stimulated flower induction in one- and two-year-old corms, there was no difference in flowering percentage between 1 and 2 g 1^-1 GA₃. Three-year-old corms produced inflorescences without GA₃ application, and inflorescences appeared earlier in three-year-old corms than in one-and two-year-old corms. Some abnormalities were found in plants from one-and two-year-old corms. These included inflorescences with twisted or hooked spadix, inflorescences without male or female organs, and inflorescences fused with leaves.

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Amorphophallus paeoniifolius (Dennst.) Nicolson (elephant foot yam) and A. muelleri Mill. are commonly cultivated under tree canopies. They are usually harvested two to three years after the planting of one-year-old corms. However, information about suitable cultivation periods and shading levels is limited. The present study was conducted in a field located in Bogor, West Java, over a period of three years at four shading levels: control (0%), 25, 50 and 75%. Regardless of the shading level, the fresh mass of the corms increased exponentially in a year in elephant foot yams, while linearly in A. muelleri. Leaf size increased with the increase in the shading level, resulting in the production of large daughter corms at a low light intensity. About half of the A. muelleri plants flowered in the third year under the 75% shading condition, while no elephant foot yam plants flowered under the same condition. Daughter corms reached a commercial size two years after planting in A. muelleri and three years after planting in elephant foot yams under the 75% shading condition. These results suggested that both species are shade-loving plants and that A. muelleri could be harvested one year earlier than elephant foot yams under shading conditions.

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Taking into consideration that the development of a technical methodology is a fundamental goal of international technical cooperation projects, there is a need for comprehensive and participatory approaches to development that incorporate both technical as well as social aspects. In association with a Bolivian counterpart organization, a technical cooperation project of JICA (the Japanese International Cooperation Agency) for afforestation and erosion control was implemented in a small watershed area encompassing three communities, whose members participated in the project over a period of five years. In implementing the project, the participatory approach caused basic problems. Through the establishment of a community based organization in the project area, community members were encouraged to actively participate in erosion control activities. However, the final project evaluation mission, realized in March and April 2003, found that their participation, while functional, was not self mobilized. Focusing the objectives of participation, whether it is a means or end, the authors concluded that participatory approach was effectively utilized as a means, though the broad aim of participatory development was not sufficiently achieved in this project.
In the future, the following points should be well considered prior to the implementation of international technical cooperation projects on soil erosion control, watershed management and related activities which take the participatory approach: monitoring the relationship between the system of incentives and the achievement of project goals must be undertaken, while at the same time it is neither reasonable nor necessary that the participatory approach be incorporated into every technical cooperation project.

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