GA-induced seedless berries containing immature abnormal tissues in the internal parts of matured berries, were found in Muscat Bailey A grapes. The development of the abnormal tissues was studied and a couple of factors affecting their formation are discussed.
1. The abnormal tissues developed inside the flesh were of three types; globular, spindle and cylindrical in shape. While the flesh was mature, the abnormal tissue was immature and covered with green pericarp-like tissue. Of these three types, globular and spindle ones were mainly produced in GA-treated berries, and cylindrical one mostly appeared in non-treated berries.
2. The abnormal berries were produced more frequently by GA-treatment, and vigorous shoots and perfect hermaphrodites were predominant for their formation. The formation of abnormal berries was significantly correlated with the formation of GA-induced seedless ones at a 1% level. The abnormal berries were formed to a greater extent, when GA was applied 12 days before anthesis, than the applications at 22, 17, 7 and 0 days. The abnormal tissues were also well found in berries with three locules.
3. The symptoms that precede abnormal berry development, were observed early in flowerets at anthesis. The abnormal tissues were originated from a basal portion of core as a protuberant tissue and frequently in a larger ovary. Some abnormal tissues formed corolla, anther and female organ on the basal core at anthesis and developed into flowers during green stage, and finally matured to fruits that obtained seeds at ripening stage.

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This paper deals with the effects of application of CaO₂ and CaO and soil moisture regimes, pF 1.3, 2.2 and 2.6, on the incidence of ‘Yuzuhada’ disorder. The effects were examined during the period from 1973 to 1977, using potted eight-year-old Nijisseiki pear trees that so far had developed the symptoms of ‘Yuzuhada’ disorder more or less every year. Besides the pot tests, multivariate analysis was applied to the data obtained by chemical analysis of soils, fruits, and leaves to detect major contributing factors. This information is necessary for devising an effective control measure of the ‘Yuzuhada’ disorder. The results obtained are summarized as follows:
1. In the treatment of pF 2.2, the incidence of ‘Yuzuhada’ disorder was decreased markedly by CaO₂ and CaO applications even in the first year after the application and thereafter decreased further to as low as 13 percent in the fourth year. Fruits of these treatments had grown fully and showed considerably high marketable quality with slight symptoms of the disorder. Under both pF 2.6 and 1.3, however, CaO₂ application increased the percentage of ‘Yuzuhada’ fruit up to 60 percent, and CaO up to 80 percent, though the calcium applications decreased it to less than 50 percent in the first year only.
2. When expressed as percentages of dry weight basis or as total quantity per fruit, N, P, and K contents of fruits of pF 1.3 treatment were lower than those of pF 2.2 and 2.6, and Ca and Mg contents of pF 1.3 treatment were lower than those of pF 2.2. K and Ca contents of fruits were lower, while N content was higher, under pF 2.6 than under pF 2.2 and 1.3.
3. P, K, and Ca contents of leaves expressed on a dry weight basis were lower under pF 1.3, and K and Ca contents were lower under pF 2.6 than under pF 2.2. Exchangeable Ca and Mg contents of soils were decreased in the pF 1.3 treatment, while exchangeable K and Ca were decreased in the pF 2.6 treatment. Besides, total calcium content of the soil was lower under pF 1.3 and 2.6 than under pF 2.2. These facts imply that the fixation and leaching of basic elements occurred in the soil by drying and moistening treatments, respectively.
4. Fructose and sucrose contents in the fruit were increased, while glucose and sorbitol contents were decreased, by the calcium applications under pF 2.2. Under pF 1.3 and 2.6, however, neither fructose nor sucrose was increased and glucose or sorbitol was not decreased by calcium application. On the other hand, titratable acidity of fruit juice was somewhat increased under pF 2.6 and conversely decreased under pF 1.3.
5. Respiration rate and ethylene production in the fruit were more increased under pF 1.3 and 2.6 than under pF 2.2. In other words, fruit maturity was markedly progressed by both drying and moistening of pot soils.
6. Principal component analysis was applied to the data obtained by chemical analysis of soil and plant materials. Ca contents of both fruit and leaves significantly contributed to the first principal component, while various factors, such as the content of exchangeable Ca and Mg, percentage calcium saturation, and pH values of soils, contributed to the second principal component. Additionally, amounts of CO₂, ethylene, and starch production also seemed to be significant factors pertaining to the incidence of ‘Yuzuhada’ disorder. The results of multiple regression analysis showed a tendency similar to those obtained by principal component analysis. It is suggested that factors which significantly contribute to the first and second components may influence the incidence of ‘Yuzuhada’ disorder developed on the Nijisseiki pear tree.

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Grape cuttings, Vitis labruscana Bailey, cv. Campbell Early, grown in a greenhouse were examined for following effects: a) defoliation and the leaf position with respect to inflorescence, b) SADH spray, on flowering, berry set and on subsequent berry development under natural sunlight conditions.
Development of floral organs at anthesis differed depending on leaf position; that is, proximal leaf contributed to better floral size than that distal to the inflorescence. The average percent of fruiting plants per treatment three weeks after full bloom in proximal lot and in distal lot was 40.0% and 25.0%, respectively. Poor fruit set in cuttings with expanding immature leaf above flower cluster is probably attributable to the diversion of reserve substances.
SADH (2500 and 5000ppm) treatment reduced the floral development in proximal lot, while it had no effect on percent of bearing plant per treatment. SADH treatment of proximal lot increased berry set, but the treatment did not inhibit vegetative growth, because all leaves were removed, one leaf being left. In completely defoliated treatment, percent of bearing plants three weeks after full bloom was high in all lots, and cuttings with SADH at 5000ppm gave the best result in berry set per cluster.
Berry maturity in distal lot was advanced more than in proximal lot. Leaf area of distal lot is larger than that of proximal lot as was the mean berry size. SADH treatment not only resulted in poorest berry size, maturation was also retarded.

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Physiological effects of CCC on the growth of grapevine inflorescence differentiation, cytokinin activity in the xylem sap, and photosynthetic and respiratory activities of grape leaves were investigated by the application of CCC as a soil drench.
1. Shoot elongation and dry weight of shoot were not affected by CCC treatment. However, CCC caused an increase in dry weight of roots without changing any external features of the roots.
2. The top/root ratio of CCC-treated plants was reduced to about one-half that of the control plants. The volume of xylem sap of CCC-treated plants exceeded about two times that of controls.
After separation of xylem sap by Sephadex LH-20 column chromatography, at least five cytokinin-like substances including zeatin and zeatin riboside were present in the sap of control plants. The main peak of cytokinin-like activity (Compound 1) in the sap was depressed by CCC treatment, whereas the sixth cytokinin-like substance (Compound 5) appeared in the chromatograms of the sap examined.
3. Number of inflorescence differentiation in the lateral bud of CCC-treated plants was larger than that of controls. The number of inflorescence differentiation of lateral buds from the 3rd to the 5th node of the shoot was larger than that of the 8th to the 10th node of the shoot.
4. Chlorophyll content of the leaves of CCC-treated plants was higher than that of controls, especially in young leaves. Photosynthetic activity of mature grape leaves was stimulated by CCC treatment, though dark respiration was not affected by the treatment. Photorespiration rate (PIB-1) and PR/DR ratio of mature leaves were increased by CCC treatment.

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Relations of soluble solids and acid contents to fruit size were examined with fruits harvested from 9-year-old Miyagawa Wase trees grown in the Chiba Horticultural Experiment Station, Tateyama, Japan.
Fully mature fruits at harvest were sized into 5 classes and 640 fruits randomly chosen from each class were used as the material. Mean weights of fruit and the pulp, and mean concentrations of soluble solids and titratable acids in the juice were determined for each class.
1. An allometric relation, w'=Hw^h, was observed between pulp weight(w', fresh weight of a whole pulp per fruit) and fruit weight (w, fresh weight).
2. With increasing fruit size, the soluble solids concentration (brix) and titratable acid concentration in the juice decreased, but the rate of decrease tended to become smaller with an increase in fruit weight.
3. The total soluble solids content of whole pulp (x_S), estimated by the product of brix reading and pulp weight, was positively correlated with fruit weight (w), following the allometric function similar to the pulp weight-fruit weight allometry.
4. The total acid content of a whole pulp (x_A), or the product of titratable acid concentration in the juice and pulp weight, increased with an increase in fruit size, but tended to approach a ceiling value at very large size classes. This relation can approximately be expressed by the reciprocal equation, 1/x_A=(A/w)+B, a special case of the so-called generalized allometric function, 1/x_A=(A/w^h)+B, proposed by Ogawa et al. (14).
5. From these formulations of the interrelationships among fruit weight, pulp weight, and total soluble solids and acid contents of a whole pulp, relations of fruit size to soluble solids and acid concentrations in the juice and their ratio were also formulated.

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The present experiment was aimed at confirming the generally recognized assumption on the chimerism of ‘Kobayashi Mikan’. This cultivar is the so-called synthetic chimera that has arisen in grafting at the junction of satsuma mandarin (Citrus unshiu Marc.) scion and natsudaidai (Citrus natsudaidai Hayata) stock. The external features of leaves, floral parts, and fruits were examined carefully by scanning electron microscopy. From the viewpoint of chimerism, the results obtained in a taxonomic comparison of satsuma, natsudaidai, and ‘Kobayashi Mikan’ are summarized as follows:

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The mechanism of nucellar embryogenesis was studied in histological experiments and ovule cultures. Seven citrus cultivars were used as materials.
A primordium cell of the nucellar embryo, designated by the authors in a previous paper (6), was observed in the ‘Trovita’ orange ovule from 4 days before anthesis. The primordium cell was observed in the other polyembryonic cultivars from the time of flowering. However, the primordium cell was not observed throughout the developmental stages of the ovule in any of the monoembryonic cultivars studied. In the culture of ovules excised from flower buds and young fruits, nucellar embryoids were formed only in the polyembryonic cultivars. The embryoids formed in the monoembryonic cultivars originated in the fertilized egg. The nucellar embryoids formed in the polyembryonic ones were derived either from the primordium cell of the nucellar embryo or other cells which might have such a potential as to develop into the primordium cell. Moreover, the nucellar embryoids were formed in an agar medium containing sucrose only. The mechanism of nucellar embryogenesis is discussed on the basis of these results.

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The application of a tissue culture to the problem of the multiplication of male sterile plants in common onion was examined.
1. Explants each containing two inner scale bases, 2-3mm wide and 1.0-1.5mm long, attached to the disk tissue, 1mm thick, were found to be best for production of adventitious shoots. About 25 pieces of such explants may be obtained from one stock bulb, because the bulb has 4 to 6 tiller shoots which may further be divided into 4 to 6 sectors according to size.
2. The explants were grown on Murashige-Skoog medium with various levels of kinetin and NAA under a 12hr light regime at 20°C.Adventitious shoot formation was strongly dependent on the presence of kinetin, while NAA only had a modifying effect on the kinetin influence. Proliferation of adventitious shoots was at its maximum in the medium containing 12mg/l kinetin and 0.5mg/l NAA.
3. The explants excised from stock bulbs in a post-dormant stage were more active in the formation of adventitious shoots than the explants excised in a dormant stage, and produced about 10 shoots per explant in 30 days of incubation.
4. Microscopic observations of cultured explants revealed that adventitious shoots were induced directly without intervening callus from the disk tissue adjacent to the scale bases and cell division for the shoot initiation became rapidly weak after 20 days from the explanting time.
5. The divided sections of cultured tissues with one or two adventitious shoots were transferred to Murashige-Skoog medium containing 0, 0.01 and 0.1mg/l NAA without kinetin and kept under a 12hr light regime at 20°C for 20 days. Most satisfactory plantlets enduring open culture were produced in the absence of NAA.

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Recognition pollen grains were collected from broccoli and cabbage plants. ‘Crushed’pollen as a recognition pollen material was prepared by grinding pollen grains with an agate mortar, while‘untreated’pollon as another recognition pollen material was collected without artificial treatment from the anther after the opening of broccoli or cabbage flowers. Immediately after the application of recognition pollen materials, each radish stigma was pollinated further with self pollen grains. In addition, conventional self pollination was carried out as controls.
Growth behavior of pollen grains on the stigma was examined to estimate the degree of fertility. Detailed procedures used in this investigation are stated in the previous paper.
In the self pollination (controls), a few radish pollen grains could germinate on the stigma. Pollen germination, however, was fairly increased by the preceding application of‘crushed’or‘untreated’broccoli pollen grains. In such cases, many pollen tubes could penetrate the barrier of stigma papillae. A few emptied pollen grains that had transferred their contents into the developing pollen tubes were observed on the stigma.
The percentage germination of radish pollen grains was increased considerably by the preceding application of‘crushed’or‘untreated’cabbage pollen grains. In general, the length of developed pollen tubes that were produced by the cabbage pollen application was shorter than that of pollen tubes by the application of broccoli pollen grains. In such cases, few emptied pollen grains were recognized on the stigma.
It seems that the preceding application of recognition pollen grains collected from broccoli or cabbage plants in combination with the following self pollination partially overcomes the self-incompatibility of Japanese radish.

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In the meristem culture of Cattleya alliance, both explants and culture media usually turn reddish brown by enzymatic browning in the presence of phenolic compounds that are produced by explanted tissues. Under such conditions, cultures eventually die because of toxic effects of phenolic compounds. Thus, some factors which influence the survival of explants in connection with phenolic compounds produced by new pseudobulb tissues were examined in this study.
1. Lateral buds with bracts were cut off from new pseudobulbs and then explanted in the liquid RM medium which was renewed once every week for 3 weeks. After that, bracts and leaf primordia were removed to get apical domes of explants exposed, and then transferred to the solid RM medium. Such an explanting technique seemed superior to the current method in both growth and survival rates of explants.
2. When tissues were incubated in sterilized water, fully mature lateral buds of new pseudobulbs that had grown 9 to 12cm in length were better than those of younger pseudobulbs in both survival rate and adventitious bud formation in vitro. The former was revealed to produce less amount of phenolic compounds than the latter.
3. When cultures were incubated in sterilized water, phenolic compounds produced in tissue pieces of pseudobulbs were less in amount at 15-20°C than above 25°C. Excellent growth and survival rates of explants were achieved when the temperature was kept at 15-20°C during the first 4 weeks from explanting (during the first 3 weeks in a liquid medium and subsequent 1 week on a solid medium), and thereafter 25°C.
4. Though medium pH had no direct effects on the growth of Cattleya plantlets within a range from 4.2 to 6.0, maximum survival rate was obtained when medium pH was adjusted to 5.5. Tissue pieces of new pseudobulbs produced less amount of phenolic compounds when incubated in sterilized water of pH 5.5 than in media of the other pH range and compositions.

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Interrelated effects of daylength and winter chilling on the growth and dormancy of several woody plants were studied for two consecutive years.
1. The shoot growth of Japanese holly (Ilex crenata Thunb.) cuttings remained linear throughout most of the test period at 16hr or more daylengths, though under daylengths less than 16hr the shoot of Japanese holly cuttings ceased to elongate after a certain period of growth. Shoot growth of Japanese black pine (Pinus thunbergii Parl. ) seedlings seemed daylength-independent.
2. The shoot of Japanese holly cuttings did not respond to winter chilling, though they showed active growth under long day conditions. Contrary to Japanese holly cuttings, the shoot of trident maple (Acer buergerianum Miq.) seedlings became dormant even under long day conditions and eventually died unless it had previously been exposed to winter chilling. When trident maple seedlings were subjected to winter chilling, however, their shoots continued to grow vigorously even under short day conditions, that is, the shoot growth of trident maple seedlings was typically chilling-dependent. The shoot growth of Japanese privet (Ligustrum japonicum Thunb.) seedlings was facultative-long-day-dependent. The winter chilling treatment did not affect the shoot growth of sweet viburnum (Viburnum awabuki K. Koch) cuttings and Japanese black pine seedlings showed facultative-chilling-dependent responses along with facultative-long-day-dependent behavior, whereas that of sawleaf zelkova (Zelkova serrata (Thunb.) Makino) seedlings was facultative-chilling-dependent and daylength-independent.
3. The seedlings of Japanese privet and Japanese black pine which were not exposed to winter chilling produced much fewer numbers of lateral shoots under both long and short day conditions than those exposed. No matter what daylengths Japanese privet seedlings and Japanese holly cuttings received, more than half of them bloomed when they were exposed previously to winter chilling, whereas those that were not subjected to winter chilling never bloomed.

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In this experiment flowering periods of branching stock plants sown in the summer were examined. In addition, intercultivar differences in temperatures allowable for flower bud initiation and flowering, and difference in response of flowering of pinched and non-pinched seedlings to low temperature conditions were investigated, using extremely early, early, medium, and late flowering stock cultivars.
1. Shoots of seedlings of 12 cultivars sown on August 6 were pinched immediately above the 10th node from the basal point and grown thereafter in an unheated plastic house. Every cultivar initiated flower primordium formation from October to November and flowered from the beginning of December to the middle of March in the order of extremely early, early, medium and late flowering cultivars. Mean temperatures at the time when flower bud initiation was observed were 22°C in the extremely early, 18°C in early, and 13°C in both medium and late flowering cultivars.
2. Seedlings with 2 unfolded leaves were planted in glass-houses where minimum temperatures were maintained at about 3°, 8°, 13°, 18°, and 23°C. Shoots of most seedlings were pinched above the 12th node from the basal point.
At minimum temperatures higher than 23°C, about 75% and 50% of the treated plants flowered in the extremely early flowering cultivar, ‘Iwaiaka No. 1’and‘Sevenweek Trysomic Dwarf Double’, respectively. At minimum temperatures higher than 8°C, from 70 to 100%, and about 17% of the treated plants bloomed in the early flowering cultivar, ‘Iwaiaka No. 2’, ‘Wakazakura’, and‘Dwarf Ten-week’, respectively. All of the medium flowering cultivar, ‘Kanchidori’, flowered at temperatures higher than 13°C. In the case of late flowering cultivar, 75% of the‘Matsudoaka’ plants and 80% of the‘Trysomic Hidouble Lilac-lavender’plants flowered at minimum temperatures higher than 13°C. Thus, it seems that the highest temperature which can induce flower bud initiation are 23°C for the extremely early flowering cultivar, 18°C for the early flowering cultivars, 13°-18°C for the medium flowering cultivars, and 13°C for the late flowering cultivars.
Within temperature regimes allowable for flower bud initiation, flower-budding and flowering periods on both the main and the lateral shoot were earlier in early flowering cultivars than in late flowering ones. The number of nodes to inflorescence was also smaller in the former than in the latter.
When plants before pinching were grown under temperatures allowble for flower bud initiation, the number of nodes to inflorescence on the lateral shoots of all the pinched plants was somewhat decreased below the number of nodes to inflorescence above 12 nodes on the main shoot of non-pinched seedlings.
In all cultivars, there was little difference between two treatments in the number of nodes to inflorescence on the lateral shoots. In one of the treatments seedlings were grown under allowable temperatures from the 2-leaf stage, and in the other treatment the seedlings received low temperatures only after the pinching. Number of days from the pinching to the flower-budding and the flowering was somewhat decreased by low temperature treatments after the pinching.
3. These results suggested that maintaining the temperatures above the low temperature regime allowable for flower bud initiation for a certain period is necessary for the production of cut flowers that have the stalk of sufficient length.

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This work was designed to investigate the effects of chilling of parent bulbs on the subsequent growth of inner bulb cores and also of scale bulblets that develop from the detached middle scale of Easter lily (Lilium longiflorum Thunb. ) cv. ‘Hinomoto’.
After the parent bulbs, 14-15cm in circumference, were stored at 25 and/or 10°C for 35 days, the outer and the middle scales were detached from parent bulbs. Of these scales the outer scales were discarded, and the middle scales and the remaining bulb cores (inner bulbs) were planted at the depth of 3cm in wooden boxes and grown in the open field.
The number of newly formed scale bulblets became larger as the chilling duration was increased. The chilling treatment increased the production of Epigeous Type Plants (ETPs) and decreased that of Hypogeous Type Plant (HTPs). In contrast with inner bulbs, leaf emergence from the scale bulblets was delayed as the chilling duration was increased.
In the treatment of 4 to 5 week chilling, 90% of the inner bulbs almost simultaneously sprouted shoots, but the others remained dormant until the end of the experiment. All of the plants which sprouted shoots were tall in height and initiated the flower bud. In the treatment of 0 to 2 week chilling, however, inner bulbs produced very late but fairly concurrent shoot sprouting, and 100% of them completed the sprouting within 5 weeks. These plants were low in height and failed to initiate the flower bud. In the treatment of 3 week chilling, some of the inner bulbs developed shoots rather rapidly and the others slowly. Thus, the percent emergence of shoots in this treatment increased most slowly among the treatments. Plants with early shoot emergence were tall in height and initiated flower bud, whereas those with late shoot emergence were low in height and remained vegetative as in the treatment of 0 to 2 week chilling.
From these results obtained it was concluded that effects of low temperature were essentially different in chilling duration and altered by the physiological condition of individual bulbs. Shorter chilling exerted almost no effects on the physiological condition of bulbs, whereas long chilling seemed to exert effects that were different in the maturity of bulbs. In other words, in more aged bulbs the chilling promoted shoot emergence and flower bud initiation, whereas in less aged bulbs it produced a dormant condition.
The effects of chilling on the leaf and/or shoot emergence were different for the scale bulblet and the inner bulb. The leaf emergence from the scale bulblet was retarded but that of the inner bulbs was promoted as chilling duration was increased, though in the latter case its effects were confined to the more aged bulbs. This fact suggests that the leaf and/or shoot emergence of scales detached from a bulb is essentially different from that of scales which are left intact with the parent bulb.

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The incidence of mechanical injury produced during the processes of sorting, washing, and packing, and effects of pertaining factors on fruit quality were determined experimentally with satsuma mandarin fruit.
1. Under the quasi-static load of 10kg, various types of surface abrasion and internal bruises were caused in the treated fruit. Collapse of the oil gland and partial rupture of peels were observed as the first signs of mechanical injury. Inside the fruit, separation and rupture of locular membranes and breakdown of juice sacs were produced, which necessarily caused exudation of juice from sacs into intervesicular spaces of fruit.
2. When quasi-static loads of more than 10kg were applied to the M-sized fruit, the peel was readily ruptured. The rupture of locular membranes and breakdown of juice sacs were produced by the application of loads of more than 8kg and 4kg, respectively. When accompanied with rotating treatment of fruit, juice sacs were broken with loads as low as 2kg.
3. The severity of breakdown of juice sacs was evaluated conveniently by determining the amount of exudate produced by infliction of pressures. The amount of exudate contained in the intervesicular spaces could be determined by measuring the weight increment of blotting paper sheet which had absorbed the exuded juice when peeled pulp segments were pressed lightly on the blotting paper.
4. In order to determine the effects of factors pertaining to mechanical injury, behavior of traveling fruit in the packing line, intensity of loads inflicted on the fruit, and bruises produced in the line were examined. Most types of mechanical injuries were produced mainly in the processes of mixing, washing, waxing, sizing, and packing of fruit and sealing and stacking of boxes. Dropping impact, compression, and surface abrasion were the main factors of fruit deterioration.
5. The rupture of peels due to artificial dropping was diminished by preparatory drying of fruit. In the line processes of the actual packing house, however, preparatory drying did not show any preventive effects against mechanical injury.

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This paper deals with the breakdown of juice sacs produced in the processes of sorting, washing, and packing in connection with effects of the pertaining factors.
1. The severity of breakdown of the juice sacs that had been subjected to the impacts inflicted in all of the line processes was 5 times greater than that of juice sacs that had passed through only the first process of fruit handling in the packing house.
2. Breakdown of juice sacs was produced principally in the processes of dumping, mixing, and packing of fruit, and sealing and stacking of boxes. Two main factors that cause breakdown of juice sacs were dropping impact and compression.
3. Effects of fruit size, physical properties of peels, and preparatory drying on the breakdown of juice sacs were examined in connection with dropping impact and compression. In fruit smaller than L-size, fruit with relatively thin peels, and fruit that were subject to peel puffing, juice sacs were more susceptible to the breakdown because of tenderness of peels. Preparatory drying was also revealed to increase the breakdown of juice sacs caused by dropping and compression. A most possible reason is that firmness of fruit, especially stiffness of peel tissues, may considerably be decreased by the preparatory drying of fruit.

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