1. In order to estimate the amounts of the nutrient elements absorbed by Japanese persimmon trees, all parts of a 9 year old tree in the persimmon orchards of Horticultural Division (Okitsu), Tõkai-Kinki Agricultural Experiment Station were separated, weighed and analysed. Trunk, branches and roots were divided into new and old tissues of both bark and wood.
2. The dry matter weights of these parts of the tree were as follows:
Leaves 3.96kg, fruits 5.06kg, one year old branches 1.13kg, larger branches and trunk 13.29kg, fine roots 0.59kg, other roots 10.56kg and total 34.59kg. All the new tissues formed in the current year amounted to 18.04kg.
3. The amount of these new tissues was 52% of total weight of the tree and sum of leaves, one year old branches and fine roots was about 60% of total new tissues.
4. Analytical data showed that one year old branches had the highest contents of N, P₂O₅ and K₂O in top parts of the tree and in the root, young fine roots had higher contents than the older parts.
5. Total amounts of nutrient elements contained in this tree were 323.33g of N, 96.40g of P₂O₅ and 251.39g of K₂O and amounts of these elements in the new tissues were 213.63g of N, 57.61g of P₂O₅ and 183.15g of K₂O. Sum of these elements in leaves, fruits, one year old branches and fine roots was N 70%, P₂O₅ 56% and K₂O 79% each of total of these elements in all the new tissues.
6. From these data, amounts of the nutrient elements absorbed by Japanese persimmon trees were 8.55kg of N, 2.30kg of P₂O₅ and 7.33kg of K₂O based on that trees were planted at the rate of 40 trees per tan (1/4 acre) and produced 380 kan (1425kg) fruits.

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To know whether the soil moisture relationships with seedling trees are applicable to grafted trees, young peach seedlings and grafted trees were grown on the soils which had been regulated to 10, 20, 30, 40, 50 and 60 per cent moisture on dry basis.
Hardly any differences were found between the seedlings and grafted young trees on wilting and discoloring of leaves and growth curve of lineal shoot growth. But grafted trees seemed to show such morphological disorders a little earlier than seedlings. Soil temperature during the experiments was maintained less than critical high temperature.

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In the regions of high altitude in Nagano Prefecture, cabbage seedlings to be set into fields are transported from the regions of low altitude where they has been raised in beds. Experiments were carried out to determine the optimum size of seedlings to be set into the fields and the optimum time of transplanting from the warm regions in spring. The results obtained vere as follows:
When large seedlings were set into the fields of the high altitude early in the season, they were apt to form imperfect flower stalks and to develop side shoots forming small heads such as Brussel's sprouts, pointed heads, or rosettes. It was not safe to plant large seedlings having six or more leaves early in the spring, because they were inclined to form flower stalks when exposed to low temperature below 10°C for more than 30 days.

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1. Minowase, a summer variety of Japanese radish, was planted successively at the three regions of different altitude in Nagano Prefecture, Nagano (360m), Fujisato (710m), and Sugadaira (1, 390m), in 1949 and 1950, in order to clarify the most favorable temperature for its vegetative growth.
2. Minowase formed flower buds when it had been planted early in the season when the minimum temperatures were lower than 16°C for more than 15 days after sowing.
3. Development of seed stalk of Minowase was forced when it was planted early in the season when the minimum temperature was lower than 12_??_13°C, and the lower the temperature, the larger the percentage of bolting plants, The earliest bolting was observed 40 days after planting.
4. It seems that vegetative growth of Minowase can bedivided into two phases: the first phase of about 20 days after planting during which the growth is rather slow, and the second phase during which the root develops very quickly.
5. The most favorable temperature for the vegetative growth of Minowase was from 17 to 23°C in the mean temperature. It is not sensitive to temperature in the first phase, but becomes sensitive in the second phase.
6. On the region of 800m high above the sea level, where the mean temperature, does not exceed 23°C, the culture of Minowase is easy even in summer season. The lower the altitude, the more difficult the culture of Minowase in the summer season. as the temperature exceeds the optimum range for its vegetative growth. In the lower regions, Minowase should be planted so as the time of root development may be occur at the temperature range of 17_??_23°C in spring or fall.

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The amount of oxygen absorbed by the vegetable roots which were cut off the stems was compared with that of the roots which attached leaves and stems, with 18 species of vegetable crops. Oxygen supply to roots from stems and leaves was discussed, and the following conclu sions were drawn.
(1) In these vegetables, the roots are supplied oxygen from stems and leaves.
(2) In mitsuba(Cryptotania japonica), asparagus beans (Vigna sesquipedaris), onions (Allium Cepa), and taroes (Colocasia antiquorum), the amount of oxygen supplied to roots from stems and leaves, is fairly large it amounts to above 20% of oxygen required by the roots. Such vegetables as these tolerate well to submersion.
(3) The amount of oxygen which is supplied to roots from stems and leaves in carrots (Daucus arrota) and chinese cabbages (Brassica pekinensis) cis not large.
(4) The vegetables, the roots of which do not rapidly lose their ability of absorbing oxygen when they are put in water, tolerate well to submersion. On the contrary, those of which the roots lose their absorbing power remarkably when put _??_ water, are easily affected by submersion.
But in the roots of edible burdocks (Arctium Lappa), though t hey decrease the amount of absorbing oxygen when their roots are put in water, they continue their growth for a long time even if they are put in the submerged soil, because a large amount of oxygen is supplied to the roots from their stems and leaves.
The submersion tolerance of vegetables differs according to various factors and these factors are not simple.

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1. An experiment was conducted concerning the degeneration of seeds caused by careless management, using Hikoshima Haruna as an example of slow-bolting Chinese cabbage.
2. If the seed was sown too early, the plants grew fairly large, became somewhat insensitive to the low temperature which is a factor for seed stalk development and became susceptible to cold and diseases, resulting in a small harvest of seeds. If the sowing was done too late, seed stalks developed when the plants were young, and seed production was also decreased.
3. The proper time for sowing Hikoshima-Haruna for seed production was Nov. 9th in 1949 for a warm winter, and Oct. 25th in 1950 for a cold winter, both about 10 days later than that of Nagasaki Chinese cabbage, an early variety used as a check.
4. Considering the results of low temperature treatments it seems that Hikoshima-Haruna is more insensitive to low temperature, so that the flower bud differentiation was delayed longer and the leaves by that time were more profuse than those of the check variety.
5. Weighing the seeds produced per plant, it was recognized that the earlier the seed stalk development and flowering the, greater the seed production. However, such seeds were subject to degeneration due to improper development. This relation became obscure when the sowing was properly delayed.
6. A progeny test was conducted to know the bolting character of such plants by using seeds which were obtained from self-pollinated and intra-pollinated plants. It was ascertained that seeds obtained from early bolting mother plants produced early bolting crops, and that inbreeding also brought about bad harvest.
7. From the experiments, it is concluded; (1) in stock seed production, the mother plants must be grown in heavy clay soils with precise care, and must be selected respecting to slow-bolting character; (2) in the case of commercial seed production, the sowing should be delayed properly and early bolting plants must be eliminated, to prevent the degeneration of seed as far as possible, thus enabling the production of high quality seeds in large quantities and at inexpensive cost which are the most importantfactors in seed production.

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1. The data reported in this paper include the results of studies of the effects of temperature, photoperiod and age of plant on bulb formation of 11 Japanese and 10 American onion varieties planted in the fall of 1951 at Nagano (360 m) and in the spring of 1952 at Sugadaira (1, 250m).
2. In Aichishiro, an extra early variety, bulb developed even under short day conditions of 10-12 hours if temperature was faborable and plant had grown to certain size. In Senshuki, a midseason variety, and Sapporoki, a late variety, bulb did not develop under the same conditions.
3. In Aichishiro and Kaizuka-gokuwase, both extra early varieties, plants which were sown in the fall, did not develop their bulbs in spring in spite of the sufficient day length for bulb formation.
4. Increasing the day-length to 16 hours accelerated bulb formation and topdown in the middle and late-season varieties, some of which did not down their tops completely under the natural day-length at Nagano.
5. Under the deylength of 13 hours, time of topdown was accelerated by high temperature in the early varieties, but was not accelerated in the late varieties.
6. When plants of different ages were grown in the high and cool region, the larger plants formed bulbs earlier than the smaller ones. The size of plant which was necessary to be attained before bulb formation, was larger in the late varieties than in the early ones.
7. Those results show that the factors affecting bulb formation in onion are day-length, temperature and age of plant, of which temperature and age of plant are important for the early varieties, and photoperiod and age of plant are important for the late varieties.
8. If photoperiod and age of plant were not sufficient for bulb formation of the variety, the tops did not fall down and remained erect. Long day and high temperature which promoted bulb formation, promoted topdown, too.

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1. Some experiments were carried out to know the influence of sowing dates on the ecology of lettuce varieties, New York, Great Lake, Wayahead, and Simpson.
2. As the fall crop in Shiga Prefecture, such cabbage-heading varieties as New York and Great Lake could not form compact heads when sown after the end of August, while Wayahead and Simpson formed good heads even when sown as late as in the middle of September.
3. Those that had been sown late in September to early in October could be hardiest in winter and had flower in spring, but those having been sown earlier and grown larger were injured sever4ly by the winter cold.
4. Sugar content at the beginning of December was generally higher in inner leaves than in outer leaves and it was also higher in those that had been sown later and were in younger stage.
5. Osmotic pressure was, just like the sugar content, higher in inner leaves and in those having been sown later.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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