Field and pot experiments were carried out during 1953_??_1958 to ascertain whether phosphate, potash and a foliar fertilizer containing nitrogen, phosphorus and potassium could be absorbed through apple leaves by foliage spray. The principal results obtained are summarized as follows. (1) Apple trees were able to absorb phosphorus and potassium through leaves by foliage spray of 0. 5 per cent mono-ammonium phosphate solution and of 0.5_??_1.6 per cent potassium sulphate solution. (2) Nitrogen, phosphorus and potassium in the foliage fertilizer could be absorbed through apple leaves by foliar spray. As to nitrogen and phosphorus in the foliage fertilizer, absorption began five hours after the spraying and as for potassium it was ten hours. (3) Sprays of the foliar fertilizer during middle in May to late in August increased the growth of young apple trees. (4) Sprays of the foliar fertilizer during middle in May to late in August reinvigorated an extremely weakened apple trees injured by the root. rot (Rosellinia necatrix and Helicobasidium mompa TANAKA)and suffered from the potassium deficiency. (5) The concentration of the foliage fertilizer for practical use to apple trees was 0.2 to 0.4 per cent. Spray solution of the foliar fertilizer mixed with lime sulphur caused burning of leaves, however, any burning of leaves, did not occurred mixing of the foliar fertilizer with Bordeaux mixture or with lime sulphur added ferric sulphate.
1. Apple scald is known as the breakdown of fruit peel during the storage, the cause of which has been attributed to the effect of certain volatile substances, especially esters, produced by the meta-bolism of the fruit tissue. However, the detail as to causal volatiles and the mechanism of their ge-neration is very little known, The present inves-tigation was planned to see the response of stored apples to various gasses, having possibility to be emanated through senescence and to determine their effect on the respiration of the fruit tissue, so as to make it possible to deduce what kind of metabolism should have been taken place within the fruit to initiate such a breakdown of the peel tissues. The materials used constituted of “Rails” apple from tree or stored as long as six months after harvested at the Shinshu University, Nagano Prefecture, and random picks from local retailers representing varieties of Yellow Transparent, Mc-Intosh Red, Starking, and Jonathan. 2. Gasses generally believed to have been emitted from apple fruits during the storage, are ethylene, acetaldehyde, alcohol, and ester. Esters were not used from the reason that THOMPSON and HUELIN had proved in 1951 to be not the causal agency. The first lot of fruit was kept enclosed separately in ethylene of the concentration 100, 500, 1000 and 5000 ppm. The second lot was constituted of apples sealed in 1.5l desiccator with 4ml each of acetal-dehyde or 95% of ethyl alcohol. In the third lot, apples were enclosed in larger desiccators of the capacity of 10l in which vessels containing 1, 3 or 5ml of acetaldehyde were placed separately. Res-. piration in term of μl/g/hr was measured by WAR-BURG apparatus at the temperature of 30°C by using 0.5g of diced blocks of peel and pulp of apple fruit treated with gasses above mentioned. 3. Ethylene gas evidently gave an after-ripe effect in concentrations lower than 1000 ppm, but in 5000ppm fruits became softened and discolored, but not scalded, with reduced uptake of oxygen but without appreciable change in the phase of respira-tion, i.e., R. Q. being unaffected. Ethylene in ordinary concentration seems to be not causal agency. 4. Vaporized alcohol also gave no effect on the fruit. Acetaldehyde, on the contrary, gave response to an appreciable degree along with its accumulation, developing a symptom quite identical with the natural scald. At its high concentration (5ml) the tissue breakdown will reach into the innermost part leaving only upper portion unaffected within 10 days. 5. The respiration of acetaldehyde-induced scald tissues of both peel and pulp shows a considerable depression in magnitude of oxygene uptake and carbon dioxide output, and smaller R. Q. 6. Agencies reducing the activity of respiration enzymes, such as NaF, monoiodoacetic acid, and malonic acid, are added to the acetaldehyde treated tissue and compared with healthy apple not exposed to acetaldehyde in treating with these agencies. The percentage inhibition of oxygen consumption of artificially scalded apple was reduced nearly one half as much as.that of healthy fruit so treated, so that in the scalded apple the oxygen must have been consumed in some other way than ordinary respira-tion. This is proved by an addition of oxidation-reduction reactants such as l-ascorbic acid or pyrocatechol, through which respiration is greatly increased in sick fruits than healthy ones in vitro. 7. The addition of succinate gave almost identical effect to sound or sick fruit in vitro, while the pyruvate caused sick fruit to generate unusually large amount of carbon dioxide, more than twice as much as that of the sound fruit. Metabolism of sick fruit, therefore, seems not necessarily enclosed within tricarboxylic acid cycle but the large amount of pyruvic acid consumption may have contributed to produce excessive acetaldehyde
In order to clarify the effects of temperature on the function of pollen and pistil in the common bean, experiments were carried out, using a dwarf variety “Masterpiece”. The results obtained are summarized as follows: 1) The fertilizing ability of pistil occurred from 3 days before anthesis. Set percentage increased gradually toward the day just before anthesis. 2) By the method of cutting style after pollination, the authors studied the velocity of elongation of pollen tube. In the case of cutting after 1 hour, a few pods were secured, and the later the cutting time, the higher the set percentage. But the increase in set percentage was very small when the temperature was high. 3) The potted plants were placed under the constant temperatures between 10°C and 45°C for 4 hours, after pollination and then the styles were cut off. No pods were secured under 10°C and 45°C, and there were observed only very poor set under 30_??_40°C, while good results in the set of pods were obtained under 15_??_25°C. 4) To study the effect of alternating tempera-tures on set percentage, the 2 plots were set, one from 25°C to 35°C (each for 2. 5 hours) after pollination and the other from 35°C to 25°C. The set percentage of the former was worse than that of the latter. 5) The potted plants were placed under constant temperatures between 10°C and 45°C for 4 hours, and then were pollinated. Under 10°C and 45°C, no pods were secured. But under the range of 15_??_40°C, the set percentages were pretty high and there were no significant differences among them. It seems, therefore, that the pistil adapts oneself to wider range of temperature than pollen.
Experiments were carried out to clarify the effects of nitrogen supply for the various stages of growth on the yield and quality of potatoes (var. Irish Cobbler) in the sand culture. Seed potatoes were planted late in March (1955) or early in April (1956), and plants were harvested early in July (1955) or middle in July (1956). The concentration of nitrogen in the solution was 140 ppm and other nutrient elements also were supplied sufficiently. The results obtained are as follows. (1) The emergence of tubers in the minus nitrogen treatment was delayed five days compared with that of the control treatment in 1955. But the difference between both treatments was only two days in 1956 experiment, in which larger seed potatoes were used (seed weight was 42_??_43g in 1955, while about 110g in 1956). (2) In both years, plants which were withheld nitrogen supply after late in June (almost ceasing stage of top growth) showed earlier yellowing of ower leaves, but their yields did not fall behind the control plants supplied with nitrogen throughout all stages of growth. But, when nitrogen supply was discontinued after late in May (begining stage of tuber thickening), or early in June (vigorously growing stage of both top and tubers), yield decreas-ed considerably. On supplying with nitrogen after early in May (completing stage of emergence), top growth caught up soon with that of the control, but tuber yield did not reach. And yield of plants supplied with nitrogen during the period between early in May and late in June, was almost the same as the yield of the control plants. Further, nitro-gen supply being delayed till late in May, yield lowered considerably. (3) As to tuber quality, there were no distinct differences in dry matter percentage among the treatments But, in ascorbic acid and total nitrogen, the earlier nitrogen supply was discontinued, or the later nitrogen supply was delayed, the lower were their contents. In conclusion, the period most needed for nitrogen in this experiment, was between early in May (30_??_40 days after planting) and late in June (about 80 days after planting), and nitrogen supply from planting to emergence was also effective for yield increase. But nitrogen supply after late in June was not effective.
Premature bolting is one of the most serious problems in head lettuce culture. In the course of ecologiol studies of head lettuce, observation on the developmental process of flower clusters and flowers was carried out in relation to bolting. After a slight elongation of the stem, the growth point of the stern thickened and rounded up, then its base was surrounded by bracts. This stage was designated as “terminal cluster differentiation stage”. Then lateral clusters differentiated in the axils of bracts succesively from top to base of the stem (“lateral cluster differentiation stage”). Bracts developed around the base of the terminal cluster (“bract formation stage of the terminal cluster”), then primordia of flowers started to develop inside of the bracts (“flower primordia formation stage”). Petals, stamens, carpel, and pappus in the order were formed successively in each flower (“petal”, “stamen”, “carpel” and “pappus formtion stages”). These developmental stages were illustrated in the figures 1_??_13.
Experiments have been continued to investigate the sex expression in Cucumis Melo L. In the present paper, the structure of flower and the inheritance of andromonoeciousness versus monoeciousness are described, and the result of comparison as regards function of pollen from either hermaphroditic or staminate flower is presented. The andromonoe-cious plant used in the experiment was commercial variety Earl's Favourite which represents C. Melo L, var. reticulatus, and for the monoecious plant No. 111 and No. 981, collected in Afghanistan and Pakistan by the Japanese expedition in 1955 were used, of which No. 111 is believed to belong to the snake melon, C. Melo L. var. fLexuosus (Fig. 1). The results obtained are summarized as followes. 1. The hermaphroditic flower on andromoneci-ous plant bore the pistil and the stamens filled with pollen, while the pistillate flower on monoe-cious plant bore the pistil and the rudimentary stamens (Fig. 3, 4). 2. Though there was a fare occurrence of the andromonoecious plant bearing pistillate flower and of the monoecious plant bearing hermaphroditic flower, it was confirmed that the monoeciousness differed from the andromonoeciousness in a single dominant allele (Table 1. 2). 3. Pollen grains of the hermaphroditic flower as well as those of the staminate flower within the same vine germinated on the artificial media (1 agar, 5% sucrose and pH 6. 5) in different degree. The difference of germination percentage of the pollen of hermaphroditic and staminate flower was significant at 5 per cent level, i.e. 75.8 per cent and 66. 2 per cent respectively after one hour of culture. No significant difference was shown in the elongation of pollen tubes, and moreover, the rate of normal pollen was as high as 95 per cent or more in either hermaphroditic or staminate flower (Table 3). 4. Either through the intra self pollination or through the neighbour pollination with pollen of staminate flower within the same vine, the yield and the market value of the mature fruit from hermaphroditic flower were the same. Comparing the character of hermaphroditic flower with those of staminate flower, no significant difference was found with regards the function of pollen, i.e. the rate of fruit setting, the number of germinable seed, and the weight of fruit or seed. From the results, it is suggested that the intra self pollination on hermaphroditic flower facilitates practical procedure of pollination, with an advantage of securing the strict inbred seed.
Although the double flowering tetraploid petunias are worthy of high admiration due to the typical gigantium of their attractive large flowers and plants growth, their available value for the popular growing is sometimes changed or decreased by the other various genetical and physiological peculiarities with which are endowed them on account of chromosomal doubling. For instance, fairly later flowering habit and exceedingly lowered seed productability of the tetraploids are almost inevitable events and are considered to be inexcusable demerits for economical culture. So in order to explain their main peculiar characteristics regard to the double- and singleness, size and coloring of flowers, and also, to seed productability by self-and cross-polli- nation, the experiments were carried out in 1955-1957, and the results were discussed as follows. (1) As the double flowering character (D) is assumed to be monogenic dominant against recessive (d) in the diploid state, tetraploid plants of DDDD, DDDd, DDdd and Dddd-typed, which were produced by crossing with various typed parents of different genic constitutions, are all expected to be double flowering naturally. However, it was found in the experiments clearly that the more number of the single flowering plants than expected theoretically appeared always in the hybrid seedlings mixed with DDDd, DDdd, Dddd and dddd-typed. The cause is now explained conveniently by the assumption that about 27% of Dddd-typed plants transgressed to single flowering owing to the overwhelming of three minor recessive ddd genes against one major D. So the all-double strains were obtained only by cross- ing between Dddd or dddd and homo-double DDDD parents. (2) The size of flowers, together with double and single, showed the wide range of segre-gation from 6 to 14 cm in diameter in all hybrids: of various combinations. Then the colors of a most of flowers in the experiments indicated the compli-cated segregation modes showing redish-purple, magenta, carmine, red, rose and pink in accordance with differences of parental combinations, and ex-ceptionally, it was confirmed that salmon color was. perhaps recessive against the above-described ones. and bred true well. (3) It was one of the most striking facts of the induced autotetraploids that the-seed production decreased remarkably to about 10 and, more percentages of that of the ordinary diploids. The causes will be attributed to the two sources. The first one is the presence of higher-graded self-and cross-incompatibility strengthened by genic com-plication due to chromosomal doubling. And the second is the peculiar restricted adaptability of the autotetraploids for the environmental conditions, especially temperature, in the growing place. Name-ly, they necessitate the definite narrower and cooler temperature zone for getting good seed pro-duction than the corresponding diploids which, on the contrary, can raise up a much quantity of seeds in the condition of hotter and wider range of environ-mental temperatures. For example, the former requires 27_??_31°C zone for increasing pollen and seed fertility and the latter 28_??_33°C, signed as the maximum point of a day in the greenhouse at Utsu nomiya. These differences will be perhaps explain ed by supposing the presence of modifying minor genes regard to fertility which are much sensible. for temperature but inactive or recessive properly in the diploid state and become efficacious on modifying the fertility firstly when they are doubled in, the tetraploid constitution.
1. In order to make the growth mechanism of dropper of tulip bulbs clear, 4 gram seed bulbs of Kansas and William Pitt were planted in October and their morphology were investigated at regular intervals. 2. It was difficult to recognize any symptom of the dropper from appearance or on examination of the section of the bulbs with the naked eye before the planting time, but in early December after two months since then the bulbs were harvested and examined, it was found that of the ones which would produce a normal type daughter bulb in each mother bulb, the primordia of inner bulb was situated in the center of the nose of the bulb, whereas of the bulbs which would produce the dropper, there was a hump in which the primordia of inner bulb was produced eccentrically on the side wall of the nose as shown in Fig. 1. 3. It was ascertained that the hump of nose which would develop into the dropper stalk was located on the opposite side of the point where the seed bulb attached oneself to its mother bulb in the previous year, and the hump (dropper), pushed its way through the scale beside the disk, elongated vertically down the ground, and produced a bulb on its tip. (Fig. 1. 2. 3.) 4. The dropper stalk has a meristem on its tip, where the daughter bulb was originated, and as its meristem produces new cells actively and sends them backward, the dropper stalk makes its way rapidly into the earth with the base of the daughter bulb at the head as in the case of peanut's gyno-phore, On the other hand, it is confirmed that the dropper stalk has the geotropism in its growing stage, because when it was harvested and kept horizontally in moisture condition, it bents its tip downward. 5. The morphology of the dropper stalk is quite similar to the basal part of the leaf stalk, that is, its center is hollow as shown in Fig. 5, and its wall has not the same thickness, namely the side where it was attached to its mother bulb is thicker than the other side. Some vascular bundles run through the dropper stalk to the base of the daughter bulb in its tip, from the leaf and others from the disk of seed bulb.
The fluctuation in auxin and inhibitor in gladiolus corm are investigated by means of paper chromatography followed by bioassay with straight growth of Avena coleoptile section. Auxin appears in the corms from growing plants, disappears after harvest and appears again in the corms stored in room temperature for two months. While, inhibitor appears in every measurement during the experiment, its activity being different. It appears in limited degree in growing corms, increases at harvest time, and reaches maximum one month after storage. Then, it decreases gradually. High temperature treatment followed by cool storage accelerates the appearence of auxin in corms. The relation of the flnctuation in auxin and inhibitor to the degree of dormancy is re cognized. Auxin is considered as IAA by the detection with spraying of EHRLICH reagent. The authors express their thanks to Mr. Y. SANO and Mr. T. NAMIKI for their kind help during this study. This work was carried out under a grant of scientific research provided by the Ministry of Educ-ation. The authors express their thanks to the Ministry of Education, too.
This study was carried out to obtain basic data on the seed production of florist crop in Tohoku region aiming the improvement of seed producing technique. Annual vnca (Vinca rosea L, var. Kermesiana) was used as the material, and its flower-ing and fruiting habits were observed comparing intact plants with pinched ones. In this experiment, the seeds were sown on the May 24 1957. The results are summarized as follows: (1) The anthesis began in early August and reached the maximum in early September. And, it continued until the frosting season, but decreased extremely after early October. (2) The anthesis on the uppermost branch was observed about two weeks later than that on the main stem. It was delayed gradually according to the height of branches downwards. On the lowest branch, a delay of three weeks was recorded. (3) The tendency was recognized that the lateral branches, on which flowers opened succes-sively during from late August to early September, showed uniform growth as the result of pinching the main stem. The pinched plant produced flowers twice as many as the intact one. (4) Seeds could be harvested from the flowers opened by early September, but not later. A consi-derable amount of seed pods could be gathered from the pinched plant in one harvest. Hence, therefore, the labour for seed production may be saved by pinching.