In order to clarify germination characteristics of pincette harvested seeds in cultivated strawberries, three different experiments were carried out, using pincette harvested seeds and blender harvested seeds of 'Sachinoka', 'Nyoho' and 'Asukaruby' cultivars. In 'Sachinoka' and 'Nyoho', the germination rates of the pincette harvested seeds were much higher than those of blender harvested seeds. However, the seed germination rates of 'Asuka-ruby' were less than 10% in the case of both seed harvesting methods. The germination rates of the blender harvested seeds which had no damage in appearance were much less than that of the pincette harvested seeds in 'Sachinoka'. Furthermore, the germination rates of out-crossed and selfed seeds in 'Sachinoka' were more than 90%, but those in 'Asuka-ruby' only were approximately 30%. From the results of these experiments, it could be considered that the pincette harvested strawberry seeds exhibited the gemination characteristics in nature, as compared with the brender harvested seeds.

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The optimum planting period of onion plugs is less than a week and large number of plugs are required because of the high planting density, with the result that the labor for producing plugs is concentrated into the period. To smooth the peak of the labor for producing plugs and to save the storage space of the seedling, the storage of the seeded plug trays was discussed. Seeded plug trays were stored up to 71days under the dark condition at 2℃. After the storage, seeds were germinated in the open-field and were transplanted mechanically. Then the cultivation experiment was carried out. The experimental results showed that the average weight of the onion was about 250g and the average yield was more than 6 tons per decare in any storing periods. There were no significant differences in the average weight and yield between stored and unstored plugs. Storage of the trays before the germination required less storage space compared with that of the seedling. These results showed this storage method of the plug trays was effective for leveling the labor concentration and saving the storage space.

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The results presented in this paper show that the return to education, as found in the total income, is positive and statistically significant. It supplements the human capital literature because it makes clear that the farmers' education is rewarded. Although the benefits of education to the sample farms are not found in their effects on crop income, it cannot mean that the households engaged in crop farming do not benefit from education. The sample data make clear that the typical household is engaged in numerous income-generating activities. Although a household's farm/non-farm profitability might not improve, its total income will increase from the improved education of the household members.

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In this study, efficient absorbing and removing method of seedling on tray was examined in order to replace poor quality seedling or blank cell to good seedling. Problems of usual contact type method were taken up, and in order to solve them insertion type method was manufactured as a trial of new type. Following results were obtained. 1) Absorption and removal method needs enough air for removing all soil and seedling in the cell. 2) Contact type method needs high suction power because it uses inflow air only from the drain hole. 3) Insertion type method uses all inflow air from chink and drain hole that can remove soil and seedling with extreme efficiency and precision. 4) How hard the surface is, soil can be absorbed by using a vertical motion.

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The purpose of this experiment is to clarify the cause of chlorosis of younger leaves and the method to remedy it on shoot in blueberry. Manganese content in chlorotic leaves was much lower than that in normal leaves. It was also found that chlorosis occurs when soil pH is higher than optimum for blueberry and exchangable manganese content in soil is low. It was considered that clorosis derived from manganese deficiency which was due to high soil pH. To remedy chlorosis the application of sulfur powder was effective because it lowered soil pH.

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The purpose of this study was to determine the effects of photoperiod on flower bud initiation in okra (Abelmoschus esculentus). Six accessions from Thailand and two cultivars from Japan were cultivated under natural day-length (12.21 to 14.26 hr), short-day (10 hr of natural light) and long-day (natural day-length plus additional fluorescent light, 3 μmol・m^<-2>・s^<-1>, for a total of 16 hr) photoperiods in early, mid and late summer in japan. Flower buds of HE022, HE035, HE045, HE047 and 'Clemson Spineless' formed at a lower node and earlier under short-day compared to long-day and natural day-length conditions in early, mid and late summer. Flower buds of HE015 and HE050 developed at a similar node and similar time regardless of photoperiod and season. Flower bud initiation in 'Emerald' fluctuated slightly with the different photoperiods and seasons. In all accessions and cultivars, flower buds continued to form under short-day conditions. But the reversion to a vegetative phase of growth after the appearance of flower buds was observed noto only in HE022, HE035, HE045, HE047 and 'Clemson Spineless' but also in HE050 and 'Emerald' under long-day conditions. Based on these results, it was thought that HE022, HE035, HE045, HE047, HE050, 'Clemson Spineless' and 'Emerald' might have a short-day response for flower bud initiation. HE015 might have a day-neutral response. The majority of photoperiodic responses for flower bud initiation in okra accessions from Thailand might have a short-day requirement.

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