With 4-year-old fruiting Delaware grapes planted in Wagner's pots, the effects of the soil oxygen concentration on the yield, and berry growth and quality were observed from the standpoint of macro-nutrient absorption. 1. With lowering soil oxygen concentration from May 1 (20 days before the blooming) to August 3 (harvest time), pollen germination and berry set as well as N, P, K, Ca and Mg contents of leaves were all inferior. Particularly, at the oxygen concentration of less than 5%, none of berries set. The percentage of germinated pollens correlated most significantly with P and K contents of leaves. 2. As the soil oxygen concentration was reduced from June 5 (15 days after berry set) to August 3, vine growth, yield, and berry growth and quality decreased greatly accompanied by a marked decrease in P, K and Mg contents of leaves and fruits at the harvest time, though each vine was uniform in both the tree vigor and fruit load in the beginning. 3. Respiration rate of excised roots decreased greatly as the oxygen concentration of the air in the manometer vessel was lowered. Particularly, the CO2 amount evolved exceeded the O2 amount uptaken by roots at the oxygen concentration of less than 5%.
1. During 1956_??_'57, fig trees (Masui Dauphine) were grown in sand culture, and growth, yield and quality of the fruits were determined in relation to the concentration and the ratio of nitrogen, phosphoric acid and potassium. 2. The greatest amount of growth in non-bearing trees occurred when the nitrogen level was maintained at 80ppm, and phosphoric acid and potassium concentrations both at 40ppm. For bearing trees, maximum growth and yield and quality of the fruits were achieved at 80ppm of nitrogen, 80ppm of phosphoric acid, and 160ppm of potassium. 3. Nitrogen was an important factor for the vegetative and reproductive development of the fig. 4. Phosphoric acid improved the quality and color of the fruits and accelerated maturity. 5. The yield and quality of the fruits were also dependent upon potassium concentration, maximum quality being achieved at 160ppm.
1. In order to investigate the effect of the physical and chemical properties of soils derived from different matrices on the growth of Satsuma orange trees, the pot experiment was carried on with 2-year-old Miyagawa wase oranges for 4 years of 1957_??_1961. Soils examined were collected from the uncultivated lands of main citrus raising area in Ehime Prefecture. The kinds of soils and their matrices were as follows: (i) Idai soil; Granodiorite, (ii) Tobe soil; Crystalline schist (graphitic), (iii) Sekizen soil; Paleozoic graywacke and lime stone, (iv) Yoshida soil; Mesozoic sand stone, (v) Ono soil Diluvial, and (vi) Ono volcanic ash soil; Volcanic ash. 2. The shoot growth, fruit yield and enlargement of trunk circumference were all the greatest in Satsuma orange trees planted in Sekizen soil throughout the experimental term. In the second vear, no significant differences of the shoot growth was found among the five soils except Sekizen soil. In the third year, Yoshida soil, Ono soil and Ono volcanic ash soil were all superior in the shoot growth to Idai soil and Tobe soil, while the formers were inferior in the fruit yield to the tatters. In the fourth year, the shoot growth, trunk circumference and yield were all better in Yoshida soil, Ono soil and Ono volcanic ash soil than in Idai soil and Tobe soil. 3. The best growth in Sekizen soil might be attributed to the chemical properties of the soil which was slightly acidic or alkaline, and rich in exchangeable cations, nitrogen applied being very effective. In the five soils except Sekizen, the chemical properties of soil such as cation exchange capacity, soil reaction, and contents of organic carbon, total nitrogen, exchangeable cations and phosphorus (water soluble, 0.002N-H2SO4 soluble and total) had no direct connection with the tree growth. Yoshida soil was strongly acidic, and Ono volcanic ash soil was extremely low in cation saturation. Nevertheless, the tree growth in both of them was not very bad, probably due to the high effectiveness of nitrogen applied under such a pot culture. Idai soil contained abundantly fine or small gravels, and Tobe soil was rich in large gravels. So, the poor growth of the trees planted in them might be a result of the marked leaching of nitrogen from them. Finally, it will be concluded that the growth of Satsuma orange trees planted in soils of different matrices may be mainly affected on one occasion by their physical properties and on other occasion by their chemical properties.
One-year-old trees of nine fruit species were planted in each pot with 45.0, 15.0 and 4.3kg of soils respectively, and their growth was measured based on the shoot length and fresh weight of a tree after 2 years. 1. The less the amount of soil per tree, the more inferior the growth was in most of fruit species. The trend was marked with peaches, figs and grapes, followed by walnuts, loquats, apples and pears in the order. However, the result was sorpewhat different with citrus trees and Japanese persimmons, the growth being most superior in the 15.0kg treatment. 2. With lowering amount of soil per tree, the root density in the soil increased greatly, as if this might be one of causes for retarding growth. However, this relation could not account fof the specific differences of the growth induced by the reduced amount of soil. It is only evident that the growth of citrus trees and Japanese persimmons which was not so much influenced even in the 4.3kg treatment was generally very slow, and the growth retarding function of their root-excretions was very weak as reported in the previous paper.
1. In Japanese persimmons, the pollens stored at -196°C and -80°C in sealed ampoules for one year gave a germination of 41.8 and 42.7% respectively, and the growth of their pollen tubes was normal. 2. When the stored pollens were taken out in the room of high temperature, their germination rate decreased rapidly. However, they germinated well in the room of the temperature lower than 10°C for one or two weeks. 3. When both the stored and freshly collected pollens were used in pollination, no differences of the fruit set, fruit development and seed number of a fruit were found between them.
1. This investigation was carried on from 1960 to 1963 with three varieties of Japanese persimmons (Jiro, Monpei and Hiratanenashi) to make clear the main factors connected with the yearly change of the average individual fruit weight of a tree. Fruits were thinned usually to one per bearing shoot in July of each year, except for on some of trees in 1963. 2. When the correlation was observed between shoot length and leaf area, and between leaf number and leaf area respectively, its coefficient was higher in the former than in the latter. Consequently, fruit number per one meter length of shoot was employed as an indicator of fruit load on a tree, dividing the total number of fruits by the total length of non-bearing and bearing shoots. 3. A significant negative correlation was always found between fruit load of a tree and average individual fruit weight. However, a significant positive correlation existed only occasionally, both between bearing shoot length and average individual fruit weight, and between seed number of a fruit and average individual fruit weight. Therefore, the fruit load of a tree seemed to have a deeper connection with the average individual fruit weight than the length of a bearing shoot and the seed number of a fruit. 4. Average individual fruit weight varied from 150 to 250g in the yearly change of the same tree as well as among the different trees of the same year. The variation coefficient expressed as a measure of dispersion of individual fruit weights was 7 to 15% regardless of the fruit load. A significant positive correlation was always found between fruit load of a tree and its yield.
1. It is well known in Nagano district that Nijisseiki pear trees will usually develop so-called“Ijoyo” (abnormal leaves) when the shoots continue to grow vigorously without being cut back for one or two years in Momozawa's training system. That is, leaves which spread nearly on and after the nineth node of new shoots, become narrow, thick and brittle, having faint mosaic symptoms. The shoots, with these abnormal leaves are somewhat stunted. The fruits born are inferior in their transverse growth. Their skin is partially lacked in lenticels and often have some russet stripes on the surface, though the taste is generally normal. 2. In the result of this experiment, the longer the length of vigorous shoots, and the later the ceasing of their elongation in the fall, the higher the developing percentage of abnormal leaves on them in the following year. The location of buds which would develop to the disordered shoots with abnormal leaves after sprouting, was restricted to the tip of the vigorous shoots. So, by cutting back the vigorous shoots at their tip during the rest period, the development of the disorder was completely retarded. However, once the abnormal leaves developed on shoots, the cutting back of the shoot had no effect as a preventive measure of the disorder. 3. In any other varieties than Nijisseiki none of abnormal leaves developed, even though the shoots grew vigorously and were not cut back in the trees trained in the same system.
1. With Japanese pears (Nijisseiki) grown under sand culture, the cell-division in the flesh development was studied from the standpoint of the nutrient contents of the dormant shoot. The very highly significant correlations existed between the cell number of a young fruit of April 20 (10 days after full bloom) and both the starch and total carbohydrate contents of the shoot of February 8. The respective coefficients were r=+.958 and +.947. The cell number was correlated also with both the reducing sugar and total sugar significantly, with the respective coefficients of r=+.602 and +.700. However, the cell number was correlated negatively with each content of the nitrogen fractions, though not significantly. 2. Furthermore, on May 8 near the end of cell-division period of the flesh (28 days after full bloom), the cell number was observed in relation to the carbohydrate and nitrogen contents of the current shoot. The correlations were found negatively between the cell number and each content of the carbohydrate fractions, and positively between the cell number and each content of the nitrogen fractions, though not significantly.
The present experiment was conducted from 1959 to 1961 to obtain the fundamental data on the flower head formation and development of cauliflower plants. The following was noted. 1. It was suggested from the relations between the sowing time in spring and summer and the growth behavior of various cauliflower varieties that the highest yield was obtained by vigorous vegetative growth for more than 95 days with Early Snowball A, 100 days with Nozaki-wase and Italian broccoli (De Cicco), 110 days with Masuda-nakate and 130 days with Masuda-bansei at average temperatures above 20°C. Also shown was that the flower head developed well at 15° to 18°C for 55 days with Early Snowball A, and 25 days with Nozaki-wase and Italian broccoli. Comparing with the ideal pattern mentioned above, both number of days to flower bud induction, and the duration of head development were shortened owing to the temperature in spring and summer when the seeds were sown in early spring, whereas in the case of late summer sowing, the flower bud differentiated with shorter duration of vegetative growth, followed by the longer duration of head development depending on cold temperature in autumn. 2. Phytotron experiment showed that the earliness of flower bud induction was affected with temperatures, plant sizes and varieties of cauliflower plants. The larger the plant size, the shorter the chilling requirement for flower bud differentiation. The most sensitive variety to the low temperature was Early Snowball A, followed in decreasing order by Nozaki-wase, Italian broccoli, Masudanakate and Masuda-bansei. It was considered that the maximum critical temperature which induces florwer bud was 25°C for Early Snowball A and Nozaki-wase, and 20°C for Italian broccoli, and that the minimum was 5°C for all of them. It was further suggested that the optimum temperature for induction of flower bud was 13°C with Early Snowball A and it was lower with medium and late varieties. The low temperature treatment for 10_??_15 days following flower bud induction was required for normal head development, though number of days required varied with plant sizes and varieties. Leafy head was induced by shortage of the low temperature stimulus. Daily interposal of higher temperature enhanced the low temperature requirement for flower bud differentiation and normal head development. 3. It was clearly shown that the seed vernalization promoted flower bud induction when it was partially supplemented with plant vernalization in Sakata-gokuwase, Nozaki-wase and Italian broccoli.
This study was undertaken to clarify the effect of, soil on the seed production of onion. Mother bulbs were planted in large bottomless frames filled with soils differing in their origin and texture. The soils used were fluvial sand, Shirasu sandy loam, volcanic ash loam, fluvial clay loam, basalt clay and polder clay. Plant growth was vigorous in fluvial clay loam and polder clay, medium in fluvial sand and basalt clay, and poor in Shirasu sandy loam and volcanic ash loam. Leaves in the volcanic ash loam plot were abnormal and showed die back in winter. Upper portion of seed stalks turned yellow as seeds matured. This change occurred quickly and abruptly in the seed stalks growing on sandy soils, while in clay and clay loam soils, it proceeded gradually, and seed stalks retained green until harvesting date. Heavy infection of the black stalk rot disease (Macrosporium porri) was observed in sandy loam, sand and volcanic ash loam. Severe injury was induced by the Botriotinia allii in volcanic ash loam, sandy loam and polder clay. Number of florets per plant was found tc be closely correlated to the plant growth in spring (r=+0.82), when the plant growth was expressed in cm of leaf length in March. The yield of seeds was highest in fluvial clay loam, followed by basalt clay, polder clay and fluvial sand. The yield was poor in Shirasu sandy loam, and especially in volcanic ash loam, in which it was about one third as small as that in clay loam. It was found that the seed weight was depending on the conditions of seed stalks on which seeds were produced. Stalks remaining healthy and green until harvest produced heavy seeds, while those turned yellow quickly or affected by diseases produced light seeds with low germination rates.
Some chemical changes were examined in the mixture of soil, organic materials and calcium cyanamide during composting. Rice straw and leaf mold were used as bulky organic material. Calcium cyanamide was added at the rates of 0.5, 1.0 and 2.0kg as nitrogen per cubic meter of the mixture. The mixtures were piled in the open in mid-August, turned over twice in the fall, and allowed to mature by February. Immediately after piling, temperature of the mixture rised sharply, then falled gradually and followed to the fluctuation of air temperature. Volume of the mixture was reduced to about 70% as small as that of the original volume. No significant variations were noticed in percentage of loss of ignition. Contents of total nitrogen were decreased, and the ratios of C/N were increased. Exchangeable potassium was significantly reduced, while no apparent reduction in available phosphorus content was noticed. When the composts matured, tomato seeds were sown in the boxes filled with those varying in their composition. Vigorous growths were obtained in the straw compost with low N and leaf mold composts with low and medium N. On the other hand, straw composts with medium and high N and leaf mold compost with high N showed retardation of seed germination and depression of plant growth. Above all, the seedlings grown in the straw compost with high N showed slight burning of leaf tips four days after emergence, the burning extended soon to the leaf base, and caused death of the plant. Analyses and incubation tests of the composts revealed that normal mineralization of nitrogen preceeded in those which supported vigorous plant growth, and those which showed plant toxicity had remarkable accumulation of NH4-N, high pH, and low NO3-N content. In the latter, considerable amounts of dicyandiamide and guanidin were detected by paperchromatographic technique using FCNP reagent. Sand culture tests showed that the above mentioned toxicity symptoms were the same as those induced by the cyanamide delivertives rather than by high content of NH4-N. It was suggested that application of excessive amount of calcium cyanamide should be avoided, because of the possibility of producing cyanamide delivertives harmful to the seedlings under high pH condition, and also accumulation of high NH4-N resulted from depression of nitrification in the compost.
Light sensitive seeds fail to germinate in the dark or in seed beds when they are covered with soil. It was reported by some investigators that gibberellin is effective to make them germinable in the dark. The treatment with GA solution of some seeds of very small size is, however, not so practical, because they are difficult to handle when they are wet. In this study, attempts were made to apply GA through the leaves or capsule to the seeds. Materials used were Primula malacoides, Sinningia speeiosa (gloxinia), Calceolaria herbeohybrida, and Nicotiana tabacum (tobacco). In a series of experiments, GA solution was sprayed on the stock plants at the flowering stage or at the immature capsule stage. In another series of experiments, capsules were soaked in GA solutions of various concentrations immediately after picking. The seeds were then taken from the treated plants or capsules and were stored for a few months. These seeds were germinated in the light and in the dark, and also in the seed bed. In Primula, seeds taken from the plants sprayed with GA solution at the flowering or immature capsule stage showed about 40% germination in the dark (Table 3). The seeds taken from the capsules soaked in GA solution of 500ppm after picking showed high percentages of germination in the dark. The treatment at the immature stage was slightly more effective than that at the mature stage (65_??_76%) (Table 4). The seeds taken from the treated plants and capsules showed high percentage of germination in the seed bed as well as in the germinator (Table 6). The effect of GA treatment on the germinability of seeds in the dark was maintained for at least 15 months of storage (Table 7). In gloxinia, foliar application of GA at the flowering stage had little effect, while soaking the capsule in GA solution was effective, resulting in more than 30% of germination of seeds during 15 days in the dark (Table 9). Germination at the rate of 37% was obtained with the seeds taken from the capsule cut with a peduncle of 5cm long whose cut end was soaked in GA solution for 24 hours (Table 10). In calceolaria, soaking of the capsule immediately after picking was found to be effective to improve germination of seeds in the light as well as in the dark after 6 months of storage (Table 12). In tobacco, foliar application showed little effect on the germination of seeds in the dark, white soaking treatment of the capsule immediately after picking was highly effective. The effect was greater on the immature seeds than on the mature ones, and the higher the concentration of GA the greater the effect (Tables 14, 15 and 16). These results seem to show that GA applied to leaves and capsules are translocated to the seeds. through living tissues, though it was not clear whether GA was translocated per se or after transformed.