The purpose of this study is to establish the best method for applying granular nematicides to control nematodes. Four common methods of applying granular nematicides into the soil (the reader may refer to table 1) were adopted for the upland field to find out the best way to apply. The results were as follows:
1) As it is desirable for the soil clods to be smaller than 10mm diam. to improve the efficiency, the application methods II and IV were necessary to pulverize the soil more.
2) Though the moisture of the subsoil (15-40cm depth) was increased by the rainfall, that of the topsoil (0-5cm depth) was always constant and there was almost no recognizable difference of the water retentivity among the methods I-IV.
3) There were some differences of the bulk density in the upper layer soil (0-20cm) depending on the methods till a week after applying, but after a month, there was no difference among the methods II-IV. It became clear that the effect of the nematodes control was influenced significantly by the soil condition just after applying nematicide.
4) The peak of the nematodes vertical distribution in the soil agreed with the application depth 15-20cm of granular nematicide on using the methods II-IV. It was proved that it was very important to obtain a close agreement between the vertical distribution of the nematodes and the nematicide on using the gas diffusion type nematicides.
5) The decrease rate of nematodes was from -7% (the application method I) to -17.5% (the method IV) at a week after applying granular nematicide, and it became clear that the nematicides which have a low vapor pressure were unable to control the nematodes in an early stage.
6) The nematodes density of the test field of the method IV was 2-3 times as many as the other one, but that of the method IV decreased slowly and certainly from -17.5% to -30%, and then to -46.8% for two months. The method IV seemed to be an effectual method for the gas diffusion type of the granular nematicides.
7) As the results of comparing the efficiencies of the four application methods at a month and two months after applying granular nematicide, the duration of the effect of the method IV was longer than the other methods and valued high entirely.
8) The ratio accounting for the application times of the applications methods II-IV were 35-65% of total work time. It was considered that the improvement of the granular applicator based on the physical properties of granular nematicides was needed to improve the work efficiency.
9) Though the effect of the method IV was better than the other ones, the work efficiency of this method was very much lower. This was because in the application method IV, the tilling process, the ditching process, the applying process, the covering process and the pressing process were independent of each other. It is necessary to unify those independent processes into one working process for improving work efficiency.

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The authors made the survey of usual farm works for improving the cropping system as a part of the researches on the greenification of the loess plateau in China.
In this paper, we described social and natural conditions of the loess plateau and agricultural indices of the surveyed district, and then the results of the survey which was carried out on the sequence of crops at one village.
It was estimated that there were two kinds of crop-rotations. One was 4 years rotation, i.e. pes→wheat→millet or flax (edible oil), and another was 5 years rotation, i.e. pea→wheat→wheat→wheat→millet or flax (edible oil).
Specific characters of estimated sequence of crops were discussed from the view points of trapping and holding rain-water in soil, fertility of soil, securing of food and edible oil, and seasonal dispersion of labor force.

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The authors made the survey of usual farm works for improving the cropping system as a part of the researches on the greenification of the loess plateau in China.
In this paper, we described the farm work system of wheat, the most important crop there.
1) In the process of autumu land preparation, farmers repeat plowing and harrowing 3 times for trapping and holding rain-water in soil, and expend large amount of labor force for transporting of organic fertilizer which was made from the mixture of donkeys' dung and soil.
2) In the process of seeding, farmers sow seeds with wooden drill under the conditions of no tillage, no fertilizing deep seeding and high sowing density.
3) In the process of crop rearing, farmers work only for weeding, but it is very labor expendable work.
4) In the process of harvesting, farmers cut wheat with scikle and bind it into bundle, then they store it in large heap for halt a year. In winter, farmers thresh it with stone made roller drawn by donkeys.
5) Labor requirments of total and each process are nearly equal to Japanse one in pre-mechanized age.
6) In busy season, farmers need the aid of children and old folks.

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The outline of the XXIV CIOSTA-CIGR V Congress (Aug. 27-Aug. 30, 1990, at Helsinki) was reported. It consisted of eight sessions. One by one paper in each session was briefly commented. Also, the circumstances of the round table discussion on the role of work study and labour management in agriculture, the celebration meeting to commemorate CIOSTA fourty years and CIGR sixty years, and the one day excursion to visit three institutes and one private farm were added.

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