The musk-melon is usually evaluated or estimated by the maturity and the configuration of nets on the rind of the fruit by consumers as well as producers. In this paper, the growth of the melon, the distribution and the expansion of the nets were investigated, and their characteristics and relationship were analyzed from the view point of the information engineering. The results are as follows:
1. The longitudinal crack first broke out near the equator. The number of nets derived from longitudinal cracks of matured fruits was proportional to the radius on the latitude where the net broke out. The density of longitudinal nets did not change with tce latitude. The width of the nets was inversely proportional to the radius where the net broke out.
2. The density of nets derived from latitudinal cracks was higher than that derived from longitudinal cracks. The density of nets derived from latitudinal cracks on the circumpolar zone, near the peduncle or the stylar scar, was higher than that near the equator. The density of nets derived from latitudinal cracks is proportional to the distance from the center to the position where the net broke out. The distribution of nets was entropy-like while the growth of the difference between the growth of the pericarp and the growth of the rind tissue. The cracks broke out on the place where the velocity of stretching of the rind was higher. The greater part of the growth of the fruit after breaking out the cracks is attributed to the growth of the cracks.

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Soil pulverization is the chief aim of rotary tillage. Clod size distribution is the most commonly used index of soil pulverization. However, a method for measuring clod size distribution has not been established yet. Therefore, the present study seeks to establish a simple way of recording clod size distribution.
This paper deals mainly with the following: (a) the influence on mean weight diameter of the clod when cutting with sampler and separator, (b) the probability of reducing the number of grades in sieving, namely the number of use of sieves.
The results were as follows.
(1) In the case of down-cut rotary tillage, clod size on the upper layer was larger than that on the middle and lower layers. On the other hand, clod size distribution by up-cut rotary tillage yielded the opposite result. Therefore, when we evaluate the clod size distribution it is necessary to sample each layer.
(2) Among the three sampler sizes, statistical analysis for mean weight diameter rarely showed a significant difference between the two sampling methods. These results suggest that the separater's and the sampler's effect is no greater than that of original variance or experimental error.
(3) After Synthesizing the experimental results and conducting a simulation test which used synthetic in place of dirt clods, clearly 200mm samplers should be used with cases smaller than 25mm in mean weight diameter of clods, and 400mm samplers with cases over 25mm. In other words with practical measurement of clod size distribution, we should utilize 200mm samplers in upland field and 400mm samplers in paddy field.
(4) When the number of grades in sieving is properly reduced, we can, by applying a variation of Weibull's distribution, predict the clod size with an error level of 3%. These results show that we can estimate various clod size indices using on three sieves, provided that the mesh catches the largest clod.

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We conducted a study on harvesting cherry fruits by shaking small branches of cherry trees using commercial Japanese apricot shakers. Main results obtained are as follows.
1) Single cherry fruits of ‘Nanyou’ can be harvested from spurs within 5 seconds by shaking at a stroke length of 2, 4 or 6cm with frequency of about 900, 400 or 300cpm respectively. Larger stroke length did not cause stemless fruits. Shaking spurs with multiple fruits and leaves tended to induce more stemless fruits compared to shaking spurs with a single fruit.
2) Percentage of fruits removed from slender branches with many fruits per branch length was low.
3) Shakers with stroke lengths of 36 and 40mm did not remove fruits sufficiently and induced many stemless fruits. In field operation, stroke length of 70mm and frequency over 600cpm to the spur would be required to obtain higher harvest percentage of stemed fruits.
4) The induced stroke length of branch at the hook was somewhat smaller than the set stroke length of the hook, because the boom vibrated itself owing to its small mass.

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Almost all of Japanese agricultural fields are small and narrow. In addition to that, autumn rain falls frequently in tomato harvesting season. So the use of large size automatic harvesters mounted fruit-pickup-mechanism, for example those developed in the United States, are unsuitable for Japanese fields.
To save labour and also facilitate the harvesting of processing tomato fruits, a small size harvester (Type SK) was jointly developed by the Research Farm of Shinshu University and the Research Institute of Kagome Co., Ltd. in 1992.
1) The new harvester consists of a crawler tractor, fruit separater, hopper, bar conveyer, reverse turn flat belt conveyer, sorting table and a weighing device.
The full length, width, and height of the harvester are 3600, 1745, and 1445mm respectively.
2) After cutting the tomato stem with sickle or garden scissors, the entire plants are lifted by hand onto the fruit separater.
Separated and collected fruits are carried by the bar conveyer to the reverse turn flat belt conveyer for the removal of foreign matters. After then, the fruits roll down to the sorting table. One to three persons standing around the table, sort out inferior fruits. Finally, the selected matured fruits fall into a container placed on the weighing device.
3) Results from field experiments indicate that, 203.8kg/man/hour of matured fruits were harvested using the developed harvester.
This was 1.8 times higher in comparison with hand picking of fruits. The mechanical harvester engages 2 to 7 persons. But the output per person is almost the same regardless of the number of persons engaged.
4) In manual harvesting, fruit containers and others were frequently lifted up by hand while carrying, weighing and loading. The total weight of these amount to 6.66 times that of the harvested fruit weight. By using the reported harvester, the weight was reduced by 55.6%.
5) Although manual operations are still necessary, the small sized harvester described in this report, resulted in a remarkable improvement in harvest work. Its usefulness was highly prized by the tomato growers and consequently 51 machines have been manufactured between 1992 and 1994.
To further increase its efficiency, it is desirable to do more studies to come out with appropriate varieties and cultural methods.

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1. In order to establish a method of plant hasbandry for the direct sowing of rice on dry land, the use of a tractor fitted with experimented iron row crop tires (provisional name is star-wheel) was investigated.
It was found that vehicle mobility, fertilization and herbicide application were stablized on both the dry sown and the wet transplanting field.
1. It was found that a tractor (22kw) fitted with the star-wheels could run stably on the dry sown field, when the corn index of soil layers at a depth of 10-30cm was more than about 0.5MPa (5kg f/cm²) before flooding, about 0.6-0.7MPa (6-7kg f/cm²) after flooding, and on the wet trans-planting field, when the born index of soil layers at a depth of 10-30cm was about 0.6-0.7MPa (6-7kg f/cm²).
2. The more the tractor fitted with the star-wheels run on the wheel ruts, the more the corn index on the wheel rut decreased and the more the wheel ruts width increased.
After the tractor ran three times on the wheel ruts, the width of the wheel rut increased to 15-20cm, the lug root of the star-wheel sank to 24-20cm, and the lug top of that sunk to 36-37cm.
3. The tractor could run until three times on the wheel ruts. But if the tractor has to run more than four times on the wheel ruts, it would be necessary to do farther study on tire design and running methods.
4. Fertilization and herbicide application on a large lot could be worked by one-man operation used the tractor fitted with the star-wheels.
When fertilizer was applied by a broadcaster mounted on tractor, work width was 8m, verlocity of work was 0.43-0.77m/s, effective field capacity was 0.98-1.53ha/h.
When herbicide was applied by a boom sprayer mounted on tractor, width work was 8m, velocity of work was 0.46-0.48m/s, and effective field capacity was 0.75ha/h.
When ditch was trenched with furrow opener mounted on tractor, the working interval was 7.5m, velocity of work was 0.46m/s, and rate of work capacity was 0.79ha/h.
5. In order to experiment on rice stubble damage by running of the tractor fitted with star-wheels, a control area where no tractor ran was established for the purpose of comparison.
The percentage of rice stubble damaged by running of the tractor fitted with star-wheels two or three times was 0.23-0.55% in the straightaway area, and was 4.2-12.9% in the turning area.
The damade rate of rice stubble for the total area of a large lot was 0.23-2.1%.
6. Then decrease in the rate of ear numbers of 1.9-5.3% and that in the rate of yield of 1.9-3.9% was noted.

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