The semi-mounted type onion picker with forklift was developed in order to improve the onion harvesting system on a small scale paddy field.
1. This machine picks up the onions, made in windrow on top of each row, and puts them into small containers (20kg capacity), and them trans-fers 300kg onions together to a truck. The dimensions of this picker was 2.0m length, 1.5m width, 1.7m height and 0.7m working width.
2. The operation of the system using this machine needs three workers, that resulted in high field capacity of 4.1h/10a and light labor requirement for harvest work.

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A new method of Gibberellin (GA₃) treatment was developed to avoid GA-induced hardening of the rachis in ‘Pione’ grapes (Vitis vinifera L.×Vitis labrusca L.).
GA solution including starch or gelatin, to increase its viscosity, was spread on the surfaces of clusters using the palm of the human hand. The solution with starch contained 39ppm GA (treatment at bloom) and 78ppm GA (postbloom treatment). The solution with foamed gelatin contained 139ppm GA (treatment at bloom) and 156ppm GA (postbloom treatment). The effects on berries of this GA treatment (spreading) were compared with conventional GA dipping and with untreated specimens.
GA spreading settled more berries on the clusters than GA dipping. The size, color, seedless rate, Brix and acid in mature berries treated by GA spreading were all similar to values for GA dipping.
Rachises of berries treated by GA spreading were as slender and as flexible as those of untreated berries, and were similar in length to those treated by GA dipping. GA spreading could prevent the hardening of the rachis, but not the postharvest dropping of berries. The postharvest dropping of berries treated with GA could be caused by weak berry adhesion rather than by the hardness of the rachis.

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To improve uniformity of growth of cabbage plug seedlings, we investigated the effects of seed size and sowing depth on the growth of seedlings.
1) Cabbage seeds divided by size (2-7mg by every 1mg) were sowed in plug tray at 10mm depth, and germination rate and shoot growth at cotyledon expanded stage were investigated.
(a) The germination rate of 100% did not obtained in each size. (b) Growth of shoot differed depending on the seed size. (c) The difference in seed size did not influence the uniformity of the shoot growth. The result of (b) and (c) clearly shows that uneven of the shoot growth in a tray is caused by not seed size but coexistence of different size of seeds.
2) We sowed cabbage seeds (5.0-5.9mg) into the sowing hole set in three depth of 5mm, 10mm, and 20mm, and growth of seedlings at cotyledon expanded stage were investigated. (a) The ratio of defective seedlings was decreased when sowed more than 10mm depth. (b) Growth of the shoot was inferior when sowed at 5mm or 20mm depth compared to 10mm because of the smaller root growth in the former, and because of the delay of emergence and increased dry matter partitioning to hypocotyl in the latter. These results indicates that the desirable sowing depth to be 10mm in plug nursery system in cabbage.
In concluding, we should note that it is possible to get the uniform growth of cabbage seedlings in plug nursery system by the seed selection of high accuracy of about 1mg and then sowing in the depth of 10mm.

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For the establishment of a tomato cropping system with hairy vetch (Vicia villosa Roth), effectiveness of incorporation and mulch (no-till) of hairy vetch and nitrogen fertilizer effect on tomato (Lycopersicon esculentum Mill.) growth and yield were examined, compared with tomatoes conventionally grown in a tilled field without hairy vetch (conventionally-tilled field), in 1997 and 1999. The NO₃^- concentration in the petiole sap was highest 42 days after transplanting. Though it decreased to below 1, 000ppm in tomatoes grown in conventionally-tilled field 56 days after transplanting, it remained more than 2, 000ppm in tomatoes grown in the hairy vetch-incorporated field (HV-incorporated field) and hairy vetch-mulched field (HV-mulched field). The growth index (GI) was higher in the HV-incorporated and HV-mulched fields than in the conventionally-tilled field. No difference in GI was observed among the rates of nitrogen fertilizer applied to HV-incorporated and HV-mulched fields and GI in these fields reached the recommended levels for obtaining average tomato yield at the beginning of the harvest even with no nitrogen fertilizer. The NO₃^- concentration in the petiole sap and GI in HV-mulched field was larger than those in HV-incorporated field in early period of tomato growth. Higher total tomato yields were shown in HV-incorporated and HV-mulched fields than conventionally-tilled field in both years, especially, HV-mulched field added 0-60kg/ha nitrogen fertilizer showed similar yield obtained in conventionally-tilled field with 120kg/ha nitrogen fertilizer. Yield-increase was recognized in early and middle harvest. Though tomato yield increased as nitrogen fertilizer added in conventionally-tilled field, there were no differences in yield among rates of nitrogen fertilizers applied in HV-incorporated and HV-mulched fields. Hairy vetch used for incorporation and dead mulch contributed to the increase in NO₃^- concentration in the petiole sap, and promoted tomato growth and yield, especially in HV-mulched field, compared with the conventionally-tilled field. There is a possibility to reduce the nitrogen fertilizer in the tomato cropping system with hairy vetch-incorporation and hairy vetch-mulch.

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