Experiments were carried out during three years period, from 1966 through 1968, to clarify the effects of soil moisture supplied at various growth stages on the growth, yield, and fruit qualities of young Satsuma orange trees.
Six to eight years old trees (Oiwa No.5) grown on sandy loam in earthware pipes (60cm in diameter ×60cm in depth) were used as the materials.
Water-regimes were designed as follows:
Plot Periods of water regimes
sign May-June July-Aug. Sept.-Oct.
A High Medium Medium(Low)
B Low Medium Medium(High)
C Medium(Low) High Medium
D Medium(High) Low Medium
E Medium Medium(Low) High
F Medium Medium(High) Low
G Medium Medium Medium
Soil moisture tension and moisture content on a percentage basis of water-holding capacity were pF=1 and 66% in wet-, pF=2 and 44% in medium-, pF=3 and 29% in dry-regime, respectively, on an average during the decade of 2 month. Sign in parenthesis indicates the water regime in 1968.
Results obtained were summarized as follows:
1. The growth of plants in new shoot, leaf number, trunk diameter and tree crown was good when supplied with wet- and medium-moisture in soil. The effect of drought period on the growth was decisive as the extreme during from July to August, followed by plot F regimed during from September to October in 1966. The number of flowers in the next spring was the largest in wetregimed during from July to August, and the next largest during from May to June, while the smallest in dry-regimes during the periods mentioned above, especially from July to August. There was a negative correlation between the number of shoot sprouting in the fall and the flower bearing in the next spring.
2. Thickening growth of fruits was inhibited by the dry-regimes during each period, especially at the earlier stages of growth. Young fruits werealso dropped by this treatment. Yield and average weight of fruits was higher in wet- than in dryregimes. Color development in fruits was the best in dry-regime during the period from September to October, while the least in the other two dryregimes. Part of fruit rind was enlarged in dryregimes towards the later stages of growth. The content of soluble matter and citric acid in fruit juice was the highest in dry-regime during the period from September to October, while the lowest in wetregime during the same period. Fruit juice in the other two dry-regimes presented no good taste.
3. The degree of water saturation deficit (W. S. D.) and diffusion pressure deficit (D. P. D.) in leaf was higher in dry- than in wet-regimes. There was a negative correlation between W. S. D. or D. P. D. and the rate of apparent photosynthesis and transpiration. Nitrogen content in leaf was higher in dry- than in wet-regimes, while phosphorus content in it was just the contrary.
The pore space in dry-regimed soil was occupied by a higher proportion of soil air with less water. Soil pH was high in wet-regimes. Soluble salts and NO₃-N concentrations in the soil solution were increased by lowering the soil moisture. In conclusion, the medium- and wet-regimes at various growth stages were highly desirable for the growth and yield of young citrus trees. Considering fruit qualities, the sequence of soil moisture supply seemed to be the best in wet- or medium- during the period from May to June, in medium- during from July to August, and in dry-regime during from September to October.

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In 1961, the authors have made investigations on a number of Satsuma orange orchards which were attacked by the so-called“Abnormal defoliation.” And the present study was carried out in 1966 with some of those orchards examined formerly to make clear the recent situation of the orchards which have hitherto experienced certain recovery measures for such disorder.
1. Since 1964, those orchards attacked by“Abnormal defoliation”became getting somewhat better in condition, revealing that the occurrences of defoliation, brown spots on leaves and of decay of fibrous fine roots were remarkably infrequent
2. In the orchards which were still suffering “Abnormal defoliation”it was observed that both the manganese content in leaves and the soil acidity showed definite decline as compared with the results of former survey, although those soils showed always much higher levels of manganese content and of acidity than those of the intact healthy orchard soils.
3. In the orchards examined there could be noticed that the decreasing supply of nitrogen, and, in turn, the increasing use of lime, revealing that such practical measures might be duly appreciated to be somewhat effective for recovering from this disorder.
4. Negative correlation was obtained between the content of water soluble manganese and pH level in the soil. The more higher correlation was met with the more higher level of easily reducible manganese in the soil
5. In the former survey in 1961, a close relationship was obtained among the“Abnormal defoliation, ” manganese content in leaves, soil acidity and the water soluble manganese content in the soil. But, on the contrary, the result of present examination could not reveal clearly so much closer relationship as above stated. Therefore, it may be suggested that the period of surveying would have a no less important bearing on the result obtained.

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1. In order to clarify the effects of N nutrition on the fruit qualities of Satsuma oranges, N rate experiment was carried out for 4 years on 16-year-old trees growing in concrete frame on diluvial loamy land of Ehime Fruit Tree Exp. Station. Ammonium sulphate and ammonium nitrate were respectively applied at the annual rates of 0 (non N), 200 (low N), 400 (medium N) and 800g (high N) of N per tree. The rates were split equally into March, April, July and November application. Other fertilizer elements were applied uniformly to all plots.
2. No difference in leaf N among N rates was found in the 1st year. Though the N concentration in relation to age of leaf varied substantially from year to year, there was the significant increase in leaf N of high N fertilized trees after the 2nd year, and the decrease in the non N. However, leaf N was not greatly different between the trees under low and medium N plot. Means of N concentration in 4- to 6-month-old leaves during the 3 years, the 2 nd to the 4th year, were as follows: 2.72, 2.94, 3.05 and 3.21 per cent in dry basis in the order of non, low, medium and high N plot. In October of the 4th year, the leaf N in non N plot decreased to about 2.60 per cent that seems to be the upper limit of low range for the nutrient status of Satsuma orange trees.
3. Yield during 4 years was not affected by N rates, and also tree vigor was not appreciably different among the low, medium and high N plot. Fruit qualities were not influenced by N rates in the 1st year. After the 2nd year, fruits showed that with increased amounts of applied N, soluble solids and acid in juice were increased, and ratios of soluble solids to acid except the 4th year were lowered. Especially in the 4th year, there was the significant difference in juice qualities among N rates respectively. The degree of increase in acid of fruits grown on the high N fertilized trees was greater than that in soluble solids. High N fertilization tended to produce a high proportion of late and poorly colored fruits with slightly thick and coarse-textured rind.
4. When the status of bearing was differential, N fertilization influenced greatly more on the juice quality in abundant bearing (small fruits) than in less bearing (large fruits). Conspicuous variation of juice quality from year to year was dominantly caused by the difference of meteorological condition in autumn. In this experiment, the fruit qualities of Satsuma oranges appeared to be affected greatly more by meteorological condition than by N fertilization. The difference of juice acid due to N fertilization occurred in young fruits in July or August. The same trend was found also in soluble solids 3 months before harvest.
5. The application of ammonium nitrate produced somewhat lighter green foliage and colored fruits than that of ammonium sulphate. Soluble solids and acid in juice were both slightly decreased by the application of ammonium nitrate, but ratio of soluble solids to acid was somewhat higher in ammonium nitrate than in ammonium sulphate. When calcium nitrate was compared with ammonium sulphate in pot experiment with young Satsuma orange trees, the fruit qualities showed remarkable difference with the same tendency.

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Effects of nitrogen forms supplied on the growth, concentrations of nitrogen fractions and carbohydrates of cabbage and turnip were investigated in the solution or sand culture.
Growth of plants in the NO₃ and the O₃+NH₄ treatments was the greatest, and growth of NH₄ plants was the smallest, and that of urea plants was intermediate.
The tendencies of higher concentrations of total, insoluble and soluble organic nitrogen were observed in the NH₄ and the NO₃+NH₄ treatments. However, such tendencies were not always found, when lower concentration of nitrogen was supplied. Higher concentration of nitrate nitrogen accumulated in the NO₃ treatment, and more ammonium nitrogen was ound in the NH₄ and the NO₃+NH₄ treatments. But, ammonium accumulation was much less than nitrate accumulation. In the urea treatment, lower concentrations of total, and insoluble nitrogen were found compared with those in the other treatments.
The concentrations of total, insoluble and nitrate nitrogen were higher at pH 7 than at pH 4 in cabbage leaves supplied with any forms of nitrogen. As for soluble organic nitrogen, the NO₃ treatment was higher than the NH₄ and the NO₃+NH₄ treatments at pH 4, on the other hand, at pH 7 vice versa. The concentration of ammonium nitrogen was somewhat higher at pH 7 than at pH 4 in the NH₄ and the NO₃+NH₄ treatments.
The concentrations of reducing and total sugars in the leaves were higher in the urea, NH₄ and NO₃+NH₄ treatments than in the NO₃ treatment. As for the concentrations of non-reducing sugar and starch, there were no consistent tendency owing to forms of nitrogen supplied. On cabbage leaves, the concentrations of reducing and total sugars were higher at pH 4 than at pH 7 in the NH₄ treatment, however, no differences of carbohydrate concentrations were found between pH 4 and pH 7 in the NO₃ and NO₃+NH₄ treatments.
As for cabbage leaves, the concentrations of potassium, calcium, magnesium and sodium were the highest in the NO₃ treatment, the lowest in the NH₄ treatment, and intermediate in the NO₃+NH₄ and urea treatments. Similar tendency was observed with regards to pH of leaf sap. There was found no difference in the phosphorus concentration owing to forms of nitrogen supplied.

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A study was conducted to obtain some informations on the mode of action of CMMP (solan).
(1) First of all, 50% inhibitive concentrations of CMMP on fresh weight of several kinds of plant were investigated.
It appeared that Japanese honewort was the most resistant of all plants tested. Descending order was as follows: Japanese honewort (9.5%)>carrot (6.1%)>tomato (2.5%)>egg plant (0.08%)> tobacco (0.04%).
(2) Referring to above result, Hill reaction and cyclic or non cyclic photophosphorylation were investigated on several kinds of plants. In consequence, both of susceptible and resistant plants for CMMP were inhibited of Hill reaction and photophosphorylation.
(3) Therefore it can not be considered that the selectivity of CMMP is caused by different actions on cyclic photophosphorylation.
For this reason, the cosideration on selective action of this herbicide reported by COLBY is denied.
(4) Chloroplast in guard cell was observed in detail after spraying with CMMP. In CMMP susceptible plants, chloroplast disappeared by destructing (as if melting) day by day and in resistant plants it was as same as the check.
(5) In cosequence, sclective action of CMMP might be caused by resistant activity for chloroplast destruction of this herbicide.

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The experiment was carried out to study the effect of vernalization on morphological and histochemical changes of shoot apex in Brassica.
In this experiment, A and AB genome varieties of Brassica were used as materials. These plants were grown in the green house until seedlings became the 4th leaf stage at 20-25°C. After that, half of them were treated to vernalization (8-10°C). At the every leaf stage, several the shoot tips were fixed by Carnoy′s solution for morphological and histoch emical studies. The preparation was made by the use of paraffin method and stained by histochemical method (PAS and Brachet reactions).
The results can be summarized as follows:
(1) Tunica layer changed from 3 to 2 layers at the end of vernalization. (2) Both PAS and nucleic acid reactions were increased during the process of vernalization. It is recognized that these reactions were resembled to the adult stage of the ordinary culture.
From the results mentioned above, it is considered that there is the pattern of the morphological and histochemical changes of the shoot apex during the growth in Brassica. The pattern is shortened its period by vernalization.

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Studies have been continued in order to elucidate the mechanisms for cross-incompatibility and to transfer genes among the species of Cucumis with x=12. In this paper the behavior of pollen tubes in pistil both in cases of selfings and incompatible crossings which failed to set fruits was studied. The materials were grown in a greenhouse from March to October and ordinarily pollinated during 7-9 a.m.. Microscopic observations were carried out with pistils fixed at various intervals after pollination. The findings obtained from the experiments of selfing and incompatible crossing were summarized in Table 1 and 2 respectively.
In case of selfing of several species, the longest pollen tube entered inside the stylar tissue within 20-30 minutes (Fig. 2), and reached the upper part of the ovary 4-6 hours after pollination (Fig. 4). The pollen tubes grew along the surface of placentae and entered into ovules through the micropyles in 24 hours (Fig. 5). In most of the fertilized ovules 2 or 4 endosperm nuclei were observed 48 hours after pollination and these embryo-sacs showed remarkable increase in their volume 72 hours after pollination (Fig. 7). These views indicate that the fertilization took place within 24-48 hours after the self-pollination. The results were in agreement with those of the previous reports by other investigators and no specific difference was found in the behavior of the pollen tube in case of selfing.
In each incompatible crossing, the most of the pollen grains germinated on the stigma of foreign species and the pollen tubes entered inside the stylar tissue (Fig. 8, 9, 10), whereas marked differences were found in the behavior of the pollen tubes between incompatible crossings and selfings. That is, the pollen tubes in the styles of foreign species showed considerably delay or the discontinuation in their growth. Thus, almost in all the crossings pollen tubes grew only short distance and could not reach even in the lower part of the style, and their tips rarely entered inside the ovary in 24 hours. These pollen tubes frequently showed the abnormal appearence such as club-shaped swelling or branching at their tips (Fig. 8).
In every crossing, where C. figarei was used as the pistilate parent, the pollen tubes could be observed in the ovary 24 hours after pollination, although these pollen tubes did not enter into ovules except a few individuals of some of the crossings. In these crossings the ovules into which the pollen tubes entered were less than in comparison to selfing of each parental species and moreover these ovules ceased development.
From above mentioned results, it may be concluded that the abnormal behavior of pollen tubes in the pistil of foreign species are closely related with cross-incompatibility barriers among the species of Cucumis.

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The best use of mulch covers constituting of a petroleum derivative, black polythene 200 gauge film, and sugar cane trash was investigated during the cultivation of a tomato crop. The optimum vegetative growth and the highest yield were observed in the petroleum mulch. Black polythene mulch, on the other hand, was found to be the best with regard to early yield. The differences in vegetative growth and yield among the mulches were due to the different retaining capacities of available soil moisture.

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1. The present report is the second one in a series of articles dealing with an extensive chromosome survey of the present-day chrysanthemums cultivated exclusively in Japan.
2. The cultivars of chrysanthemum used for the present study were as follows: Number of the large, medium and small flowered forms for cut flower use, including those of foreign origin, attained to 127, that of the pot-mum to 11, that of the cushionmum to 7, and that of the cooking form to 13.
3. Results of the present chromosome survey were compiled in Table 1, revealing the following facts. 1) Throughout the whole cultivars in chrysanthemums, excluding those of the exhibition use, there occurred various somatic chromosome numbers ranging 36 through 66. 2) The variation range in chromosome numbers showed definite difference from type to type of cultivars. 3) In general, the variation range in chromosome numbers was relatively slight with the large- and medium-flowered forms for cut-flower use (Japanese and foreign varieties) and also with the pot-mums (2n=53-56), forming a striking contrast to the conspicuous and remarkable complexities prevailing in their speciation procedures morphologically and ecologically. 4) In the present study, the lowest number of chromosomes, i.e., 2n=36, could be encountered for the first time with a certain small-flowered cultivar for cut-flower use. 5) The variation range in somatic chromosome numbers, i.e., 53-56, 63, 64, 66, which was obtained with the cooking varieties, was nearly the same as that in the large-flowered exhibition forms. 6) Intimate relationships of chromosome numbers to the crop season and as well to the flower colouring could not be ascertained with the large- and mediumflowered forms for cut-flower use. 7) An appreciable intimate relationship between flower size and chromosome number could be recognized only in a certain limited forms of the large-flowered chrysanthemum, such as the incurve-petaled Atsumono varieties. Most of the giant-flowered varieties were almost exclusively confined to those forms having nearly 60 chromosomes.

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In the previous paper, it was proposed that the respiratory pattern in ripening process of harvested fruits should be classified in three types. The present paper reports the effects of endogenous and exogenous ethylene on ripening and respiration of fruits, in relation to the respiratory pattern. The materials used were as follows: tomatoes (Fukuju 2-go) and bananas (Musa sapientum L.) as the temporary rise (climacteric) type; strawberries (Dana), Japanese persimmons (Hiratanenashi and Jiro), and peaches (Hakuto, white flesh variety) as the late peak type; Satsuma oranges (Citrus unshiu M.) as the gradual decrease type.
(1) Color development of mature-green tomatoes was accelerated by externally applied ethylene, and the effect was more obvious with late-picked fruits than early-picked ones in the same field. Climacteric rise of respiration was hastened by the ethylene applied. When the mature-green tomatoes were stored, ethylene concentration in the fruits increased markedly during coloring, and a considerable level of ethylene was found prior to climacteric onset.
(2) Green bananas rapidly turned yellow by the ethylene application. Climacteric rise took place immediately, but the peak in the rate of carbon dioxide production was much higher than that of naturally occurred climacteric rise.
(3) When strawberries were treated with ethylene at the stage of turning to white (immediately before color appearance), developments of coloring and softening were not affected. On the carbon dioxide production of the fruits, also, no effect was found. Ethylene concentration in the fruits had reached to a considerable level at the atage of turning to white.
(4) Softening of peach fruits after harvest was not influenced by ethylene treatment, and little effect was found on carbon dioxide production. Ethylene concentration in the fruits was at considerably high level even at unripe stage.
(5) Japanese persimmon fruits were markedly affected by ethylene treatment. Softening and coloring of fruits which were treated at unripe stage occurred rapidly, and astringency was removed. Production of carbon dioxide increased sharply in ripe fruits as well as unripe fruits. Ethylene concenration in the fruits was generally at low level, but some increase was observed in soft fruits.
(6) Immature Satsuma orange were accelerated the coloring by ethylene application. Marked increase of carbon dioxide production occurred in both half-green and full-yellow fruits. When ethylene was removed with vacuum pump from the fruits of which respiration had increased by ethylene application, the carbon dioxide production lowered to the extent of non-treated fruits, being different from the fruits of climacteric class, and re-application of ethylene on these fruits induced increase of respiration again. Ethylene concentration in the fruits was generally at low level throughout the storage period.
(7) It seems that the effects of ethylene treatment depend on the endogenous ethylene concentration, and discrimination between the climacteric and others can not be made from the response to ethylene applied, when the fruits of the late peak type are included.

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