Various kinds of necroses found in bud tissues of hosts (chestnut trees) were caused by oviposition and consequent gall formation by chestnut gall wasps. Necroses resulted from resisting reaction against parasites were initiated in parenchymatous tissues around vascular bundles which intervened between gall and normal tissues, and were classified as Type III. In the case of reaction of Type III, the acidic pigments failed to transfer into galls, though they were artificially applied to be absorbed through the cut surface of stems.
Tannic substances stained with FeCl₃ were scarcely found in gall tissues of resistant varieties. A small quantity of them were observed in the xylem and phloem of the host tissues but they were abundant in the parenchymatous tissues surrounding the vascular bundle system of normal tissues. The stainability was intensified not only in necrotic tissues and their adjacencies but also in the boundary regions of both gall and normal tissues. In the galls of susceptible varieties there were cells containing more tannins stained with FeCl₃. Such a reaction was not observed in the nutritive cell layer which probably functioned as a source of diet for the parasites and was not intensified in the boundary regions of gall and normal tissues.
Reaction of catechol tannins to the vanillin-HCl reagent was marked in nearby cells of the necrotic regions and in tissues which were later expected to produce browning. In contranst with this phenomenon, gall tissues and developing leaves which might produce galls after the oviposition of wasps did not exhibit any vanillin-HCl reaction. Thus, it seems likely that catechol tannins can be regarded as polyphenols formed as a result of resisting reaction against the parasite.
Prior to the production of browning, cells which could be stained with Sudan Black B appeared in the affected area. Cells reacting to the Schiff′s or phloroglucin-HCl reagents were observed in the same area, also.
Differences of gall weight depended on two strains of causal gall wasps; one produced spring galls (Kuritama) in resistant varieties and the other did not. Survival rates of the two strains were the same, and polyphenolic reaction to FeCl₃ was not detected in the larval bodies of the two strains studied.

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Four-year-old Campbell Early grape vines cultured in pots were used for the experiments. In mid March, slaked lime was applied to half the number of vines and sublimed sulfer to the remaining halve for the adjustment of soil acidity (pH) to high and low levels. Half of each set of lime or sulfur applied vines was top-dressed with superphosphate early in May. After that an amount of copper sulfate was applied to the soil of all pots, each set of vines with or without superphosphate was further divided into two treatments; half of vines were kept under water-saturated soil conditions by flooding the pots with water from late July to induce the vein-yellowing of leaves and the remaining halves were provided with adequate moisture.
1. The range of soil pH before the flooding treatment was 6.3-6.7 in the lime applied pots and 2.4-2.6 in the sulfur applied pots, respectively. Further, the available phosphoric acid content in soil was higher in the former than in the latter, and was increased by the superphosphate top-dressing. The contents of Cu in soil exchangeable with N/5 KCl were just reciprocal to those of available phosporic acid in these treatments.
2. The flooding treatment lowered the contents of N, K and Mg in the leaves of the basal part of shoots irrespective of the lime or sulfur application and the superphosphate top-dressing. The sap pH of the leaves was not affected by any of the treatments.
3. Vein-yellowing of basal leaves, detected only in the flooding treatment, was depressed by the superphosphate top-dressing and more notable in the lower soil pH condition than in the higher one. Further, the vines receiving both lime and superphosphate did not exhibit the vein-yellowing presumably caused by the excess of soluble copper in the soil even under circumstances which were suitable for the occurrence of the disorder.

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To clarify the effect of fruit load on the matter economy of satsuma mandarin trees, net production (ΔPn), dry matter loss by death and removal (ΔL), respiration loss (ΔR) and gross production (ΔPg) were surveyed in separate periods from April, 1972 to February, 1973 using bearing (4 fruits per plant) and non-bearing 3-year-old‘Miyagawa-wase’trees. Fruit load was regulated by hand thinning on July 15.
1) From April 5 to May 31 (from sprouting to arrested current shoot elongation): ΔPg per plant in this period (57 days) was 41.0g, and ΔR accounted for 74 per cent of that. New organs grew vigorously accounting for 150 per cent of ΔPn. By contrast, old organs lost considerable weight.
2) From June 1 to July 14 (from arrested current shoot elongation to fruit thinning): ΔPg in this period (44 days) was 48.1 g, and ΔR accounted for 60 per cent of that. Fruits and old organs initiated their rapid growth with retarded current shoot elongation.
3) From July 15 to September 6 (from fruit thinning to rapid fruit growth): In the bearing trees, ΔPg in this period (54 days) was 90.7g, of which ΔR accounted for 54 per cent. Further, 37 per cent of ΔPn was distributed to their fruit. In the non-bearing trees, ΔPg was 127.7g, of which ΔR accounted for 52 per cent. This ΔR/ΔPg ratio was lowest among the non-bearing trees through the whole season. Each organ of the non-bearing trees grew more vigorously than that of the bearing trees.
4) From September 7 to November 9 (from rapid fruit growth to harvest): In the bearing trees, ΔPg in this period (64 days) was 83.9g, of which ΔR accounted for 55 per cent. Further, 66 per cent of ΔPn was distributed to their fruit. In the non-bearing trees, ΔPg was 98.3g, of which ΔR accounted for 65 per cent. Further, 74 per cent of ΔPn was distributed to underground parts because of vigorous growth of root crowns and roots.
5) From November 10, 1972 to January 11, 1973 (from harvest to arrested vegetative growth): In the bearing trees, ΔPg in this period (63 days) was 35.3g, of which ΔR accounted for 39 per cent. In the non-bearing trees, ΔPg was 28.1g, of which ΔR accounted for 76 per cent. This ΔR/ΔPg ratio was lowest among those of the bearing trees through the whole season. Since the bearing trees resumed their growth after harvest, their ΔPn was larger than that of the non-bearing trees.
6) From January 12 to February 25 (arrested vegetative growth period): In this period (45 days) ΔPg was 7.7g in the bearing trees and 11.6g in the non-bearing trees. In each treatment trees showed little growth and ΔR was almost equivalent to ΔPg.
7) Annual ΔPg of the bearing trees was 306.7g per plant, and 29%, 9%, 5%, 29% and 28% of it were distributed to leaves, stems, trunk, underground parts and fruits, respectively. Annual ΔPg of the non-bearing trees was 354.8g per plant, and 29%, 13%, 5%, 46% and 7% of it were distributed to leaves, stems, trunk, underground parts and fruits (until thinning), respectively. The bearing and non-bearing trees showed approximately the same annual ΔPn values; 131.0g and 132.4g per plant. Since annual ΔPn/ΔPg ratios of the bearing and non-bearing trees were 0.43 and 0.37, respectively, it was found that ΔPg of the bearing trees was utilized for ΔPn more efficiently than that of the non-bearing trees.

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The prebloom application of SADH (succinic acid-2, 2-dimethyl hydrazide) to clusters of Kyoho (V×L) by spraying at 2500 ppm was as effective for increasing the set of seeded berries as foliar treatment at the same concentration or prebloom shoot pinching. The spraying on cluster had no inhibitory effect on shoot growth during bloom and set stages. Nearly the same trend as above was observed in Muscat of Alexandria (V) to which CCC (2-chloroethyl trimethylammonium chloride) was applied at 200 ppm. These results reconfirmed those of our earlier study. In both cultivars, the application of the growth retardants to either clusters or leaves distinctly reduced the gibberellin activity in florets at the beginning of bloom, whereas the shoot pinching raised the activity in Muscat or did not affect it in Kyoho. On the other hand, the cytokinin activity in florets was markedly enhanced by the retardant applications and the shoot pinching in both cultivars.
These results indicate that reduction of shoot growth is not essential to exert the promotive effect of growth retardants on the set of seeded berries and that the increased level of cytokinin activity in florets induced by the chemicals is causally associated with the promoted berry set.

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Farming work with agricultural machinery should be practised according to physical parameters which will not adversely affect the crop yield. The author attempted to determine the allowable range of seeding conditions for machinery cultivation of Daikon-radish and Chinese cabbage. The investigation was conducted for three years from 1972 to 1974. The results obtained are summarized as follows:
1. Germination of Daikon-radish was highly influenced by the size distribution of clods smaller than about 2.0cm in diameter in the soil, and the most satisfactory germination rate was obtained when the soil contained clods of this size at a rate of more than 40% in weight. On the other hand, germination of Chinese cabbage was highly influenced by clods smaller than 1.0cm in diameter, and soil containing clods of this size range at a rate of 25% or more in weight was favorable for germination.
2. The allowable range of depth for seeding was determined as follows: 1-4cm for Daikon-radish and 1-3cm for Chinese cabbage both in clayey loam and in sandy loam, and 2-4cm for Daikon-radish and 1-3cm for Chinese cabbage in sandy soil. The allowable range was defined to be the range of depth which would yield at least 70% germination for the plot in which the highest germination rate was obtained in the test, and which would avoid unfavorable factors to the germination such as susceptibility to damping-off fungus.
3. Root weight of Daikon-radish per plant decreased with increased planting density, but there was no significant difference in yield per unit area among the plots with different planting density. The same trend was observed between head weights of Chinese cabbage and planting density irrespective of maturing periods of the varieties tested, but there was an increase in yield per unit area with increased planting density. These results indicated that the allowable range of planting density should be determined by the prefered root weights rather than yields in Daikonradish and by the prefered head weights and yields in Chinese cabbage.
4. The increase of variation in hill spacing within rows resulted in a decrease of yield both in Daikon-radish and in Chinese cabbage, and an increase of variation both in root weight of Daikon-radish and in head weight of Chinese cabbage. This effect was higher in Daikon-radish than in Chinese cabbage.
5. The root weight of Daikon-radish and head weight of Chinese cabbage increased on a hill adjacent to a vacant hill. The rate of increase was higher in the former case than in the latter. When there were more than two successive vacant hills, the root weight of Daikon-radish on a hill adjacent to them increased slightly but no visible increase was observed for the head weight of Chinese cabbage.
6. The yield per unit area decreased with a rise in the percentage of vacant hills in Daikon-radish and in Chinese cabbage. In case of the same percentage of vacant hills, the smaller the variations in hill spacing were, the smaller the yield reduction was. When the allowable level of yield reduction was no more than 10%, the allowable percentage of vacant hills for Daikon-radish was greater than for Chinese cabbage. The variation of root weight of Daikon-radish or head weight of Chinese cabbage was proportionate to that of the distance between hills due to the existence of vacant hills. The variation in root weight of Daikon-radish was larger than that in the head weight of Chinese cabbage.

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Several experiments were conducted in order to investigate mechanisms involved in repression of Mn absorption by effect of high salt solutions, with the aid of radioactive tracer techniques.
Rates of Mn absorption by intact plants and excised roots of tomato were determined by incubating them in the experimental solutions for 24 and 3 hours respectively for intact plants and excised roots. Higher salt concentrations raised by multiplying a Hoagland solution repressed the incorporation of Mn into leaf, stem and root of intact plants, especially into physiologically active upper leaves, and also into excised roots. On the contrary, addition of polyethylene glycol to a Hoagland solution to give isosmotic potentials with multiples of it had only a slight effect upon Mn incorporation into intact plant leaves, and into excised roots as well.
Kinetic studies revealed that high salt solutions repressed Mn absorption by competing with Mn for the binding sites, and that the main competing ions might be K and Ca. In addition, the possibility that higher salt solutions disturb normal metabolism of roots to decrease mineral absorption in general including Mn in a long-term experiment was also suggested.

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Some experiments were carried out to elucidate the effects of plant size, N-nutrition and defoliation on low temperature induction of flower buds in onion plants.
The results were summarized as follows:
1. Effect of plant size.
As the index of plant size, the diameter of the leaf sheath at its base (abbreviated merely as diameter in the following) was shown to be most appropriate. It was found that the larger the diameter the shorter the period of low temperature exposure required for flower bud formation. Moreover, there was recognized the critical plant size above which plants were able to respond to low temperature and which varied with variety. Thus, in Senshuki (autumn sown variety) the critical size seemed to be 6mm in diameter and plants above 10mm in diameter formed flower bud in response to 30-40 days of exposure to 9°C, which was the most efficient exposure in this variety. In Sapporoki (spring sown variety, which, in consequence, had less chance to be selected against premature bolting), however, the critical size was about 3mm in diameter and plants above 9mm in diameter required no more than 20 days of 9°C exposure for their flower bud formation.
Plant age indicated by the growth period from sowing to low temperature exposure seemed to be less associated with the low temperature requirement for flower bud formation. Plants, irrespective of their age, required different periods of low temperature exposure according to their size.
2. Effect of N-nutrition.
Plants which were inferior in their growth under low N-fertilization formed flower bud following a shorter period of low temperature exposure than plants of rapid growth under high N-fertilization. At first sight this may be inconsistent with the result mentioned above the larger the plant size, the shorter the period of low temperature exposure required for the flower bud formation.
This can be attributed, however, to the high content of carbohydrates as well as to the high C/N ratio in N-deficient plants.
3. Effect of defoliation.
In plants tested, the brades of all leaves were cut off in varying degrees. Plants as large as 11mm in diameter formed flower buds following a comparatively small number of days of low temperature exposure irrespective of the degree of defoliation. While, in plants no more than 8mm in diameter, the more severe the defoliation the more days of low temperature exposure were required for flower bud formation. Our explanation of this result is that the site of the biochemical change which is induced by low temperature and results in flower bud formation is around the leaf bases of inner leaves and materials for such biochemical change, e. g. carbohydrates accumulate enough quantitatively around the leaf bases in large plants before defoliation, but not in small plants, thus, large plants can form flower buds regardless of severe defoliation.

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The present investigation deals with the effect of pollination on formation of mature seeds on excised placenta cultivated in vitro.
Artificial pollination was performed by the two following methods: (i) pollen grains were dusted directly onto the ovules with a placenta (placental pollination); (ii) styles were excised aseptically, cut into about 7 to 10mm in length after applying pollen grains onto the stigma, and then were inoculated on or around ovules with a placenta (stylar pollination).
Placental pollination. In self- and cross-pollination of the clone W166H, 3.1 and 2.9 mature seeds per ovary were obtained, respectively. The mature seeds which were detached from the placenta were sown on a fresh medium containing agar alone, and then some of them germinated.
Germinating pollen grains were observed on both self- and cross-pollination explants of the clone K146BH, but neither of the combinations produced mature seeds.
Stylar pollination. A number of mature seeds were obtained by self-and cross-pollination of clone W166H, that is, 12.2 seeds per ovary in self-pollination and 11.5 seeds in cross-pollination, respectively, were obtained. About one-fourth of these seeds germinated.
In self- and cross-pollination of clone K146BH, 5.2 and 5.9 mature seeds per ovary were obtained, respectively. Some of these seeds which detached from the placenta were germinated normally on a fresh medium containing agar only.
It was concluded that the number of mature seeds per ovary depends upon the technique of pollination, that is, stylar pollination was substantially more successful than the placental pollination.

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Grafting experiments were made with 12 species in Hibiscus (Table 1) to examine the affinity between species and the possibility of using grafting for breeding and cultural practice. The materials included annual and perennial or herbaceous and arboreal species.
1. When annual species were grafted on to perennial herbaceous species and an arboreal species (H. mutabilis), all the combinations resulted in good union. In some cases, grafted scions grew better on stocks of different species than on the stock of own species (control). The number of flowers was, however, reduced by inter-specific grafting (Table 2, 6 and 7).
2. Mutual graftings between the three herbaceous perennials of North American origin resulted in good flowering and vegetative growth not inferior to those of the control plants. Grafting them on to H. mutabilis stock caused a fairly decrease in the percentage of flowering to control in the second year (Table 3, 6 and 7, Fig. 1).
3. The scions of two tropical woody species united well with the stocks of three hardy arboreal species and H. moscheutos (a herbaceous perennial). Their vegetative growth was, however, inhibited and no flowering was observed except in control plants. A dwarf tropical woody species, H. pedunculatus, grew vigorously on any of the stocks, but the flowering of the scions was very poor, especially when grafted on to H. syriacus and H. moscheutos (Table 4, 6 and 7, Fig. 1).
4. Relatively good growth but fairly reduced flowering resulted from the mutual graftings between the three hardy arboreal species, H. mutabilis, H. syriacus and H. hamabo. H. mutabilis showed excellent growth and flowering when grafted on to perennial herbaceous species, but other two species on to the same stocks showed an inferior performance especially in their flowering (Table 5, 6 and 7, Fig, 1).
5. H. rosa-sinensis a popular tropical shrub, did not grow well and flower on the stocks of any species. Its use as stock also brought the same results for all scions tested (Table 4).
6. The results of all graft combinations suggested that the three species, H. coccineus, H. militaris and H. moscheutos, were, as compared with the other species, closely related to each other as shown by their excellent mutual grafting affinity (Table 3).
7. As far as the graft union is concerned, all the combinations of the species tested proved to be successful, but none of them was found practically useful for the purpose of promoting scion′s growth and of dwarfing.

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By the applications of paper chromatographic and spectrophotometric techniques quantitative and qualitative studies were made of developmental changes in the anthocyanidins in the flowers of the spring-flowering sweet pea. From the time the anthocyanin formation occurred, petals grew in weight exponentially until they reached their senescence. The logarithm of petal fresh weight increased linearly with time and served as a convenient morphological index to relate the progress of anthocyanin synthesis.
The maximum relative anthocyanidin concentrations (optical density at λ maximum/ mg dry weight) were generally attained by the petals approximately 6 days after the initiation of anthocyanin synthesis, namely, the most rapid anthocyanin formation occurred after flower opening.
Of the six kind of anthocyanidins identified, delphinidin, petunidin and malvidin were found in the deep purple or lavender coloured cultivars, cyanidin and peonidin were found in the deep red or deep pink coloured cultivars and pelargonidin was found in the salmon coloured cultivar. Furthermore, in the scarlet coloured cultivar pelargonidin, cyanidin and peonidin were found. And the relative contents of pelargonidin: cyanidin: peonidin in mature petals of the last cultivar was about 67: 12: 21.

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Natsudaidai fruits, which account for respectable fraction of Japanese citrus fruit production, have not been frozen commercially because severe bitterness develops in the pulp due to freezing. This paper describes the general aspects and the mechanism of bitterness increase due to freezing.
1. The organoleptic test showed that pulp which had been frozen at -20°C tasted much more bitter than the unfrozen raw pulp. 2. When segments were frozen with or without segment cover (membrane), bitterness of pulp (juice sacs without segment cover) taken from the former was greater than that from the latter. 3. When the segments were frozen by immersion in liquid nitrogen and subsequently stored at -20°C, the bitterness was not so severe as when they were frozen and stored at -20°C. No substantial bitterness change was found for either material during storage at -20°C. 4. The contents of soluble and total naringin in the pulp did not show any change due to freezing and during storage in the frozen state. 5. To determine the leakage of naringin, pulp or segment cover was immersed in water for a short time and filtered, then naringin contents in the filtrate were measured; this may suggest the ease of exudation of naringin. The leakage of naringin increased obviously due to freezing at -20°C as compared with leakage from the raw materials. The leakage from pulp frozen with liquid nitrogen, on the contrary, did not show any increase coinciding with the organoleptic evaluation. 6. No change of bitterness was found when extracted juice was frozen.
It is concluded that the increase of bitterness must be fundamentally due to the increase of readiness of exudation of naringin associated with tissue damage by the freezing. But the total amount of naringin is not the cause. Since most of the naringin is located in the outer part of the pulp and segment cover, it would leak out at thawing and bring about a high concentration on the pulp surface. The high local concentration of naringin causes the bitterness increase.

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This research was conducted to determine the shape, the total volume of pulp and volume, size distribution and p value (assumed average particle size) of sample′s pulp over 0.05mm in minimum size in cloudy juice taken from each process in the chopper pulper or In-Line juice extractor systems of A, B and C juice plants and to investigate changes in these volumes and values viz. each juice extraction system at these plants.
(1) It was possible to separate pulp over 0.05mm in size into ten fractions according to size by the use of washing, and ten testing sieves with 20, 35, 60, 100, 145, 170, 200, 250, 280 and 300 mesh openings. P value was estimated through the results of this sieving process.
(2) Pulp separated over 0.05mm in size was neither uniform nor regular in shape. Under the miscroscope, many pulp particles exhibited the pericarp in pieces which were torn, had ragged edges, or rectangular form. The shapes produced by the chopper pulper process displayed more torn shapes than those of the In-Line juice extractor process.
(3) The total volume of pulp, the volume and p value of pulp over 0.05mm in size were 700, 550 and 750ml, 454, 502 and 546ml, 0.74, 0.86 and 0.72mm from the chopper pulper process and 500, 650 and 450ml, 438, 478 and 372ml, 0.85, 0.89 and 0.76mm from the In-Line juice extractor process, respectively. There were differences in these values between both systems. Compared to the volume of In-Line juice extractor process the total volume of pulp and the volume of pulp over 0.05mm in size from the chopper pulper process were large but the p value from the In-Line juice extractor process was larger than for the chopper pulper process. These volumes and values with the pulper finisher process in both system were 350, 275 and 350ml, 233, 226 and 234ml, 0.22, 0.32 and 0.28mm and 256 and 250ml, 196 and 180ml, 0.27 and 0.24mm, respectively. Although the flow diagram of the C juice plant was different from that of the A and C juice plants, these values were decreased by about 1/2 or 1/3 by this process. By the centrifugal machine, these volumes and values were decreased by 150, 100 and 90ml, 104, 88 and 73ml, 0.15, and 0.14mm, respectively. These volumes and values were decreased by about 1/5.7 compared with the volume and value of the chopper pulper and In-Line juice extractor process. For that reason, it seems that these volumes and values were adjusted by the pulper finisher and the centrifugal machine.
(4) When straight juice was prepared by hand Reamer juice extractor from six Citrus Unshiu fruits cultivated in different districts there were large differences in the total volume of pulp over 0.05mm in size. It was recognized that these volumes and values were affected by the properties of the raw material.

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In order to investigate the effects of handling practices such as dropping and waxing in a packing-house line on the quality of satsuma mandarin, simulated handling tests were conducted. To evaluate the handling practices, the change of quality during storage for a week was evaluated with respect to respiration rate, ethanol accumulation, sugar content (Brix) and citric acidity. Results were obtained asfollows.
1. An increase in the respiration rate was caused by the dropping practice and that increase was proportional to the number of drops. Immediatey after dropping from a height of 30cm onto the board with repetitions of 10, 20 and 30 times, the increment in the respiration rate was 198%, 265% and 315% respectively. The state of increased respiration rate continued and did not recover to an initial state until 40 hours or so of elapsed time from dropping practice.
2. When satsuma mandarin was waxed after the dropping practice, respiration rate seemed to decrease for a short time after the waxing treatment and to increase until 4 hours of elapsed time. The author thought that it was due to the decrease in gas permeability through the peel by waxing treatment.
3. The relationship between dropping height and maximum acceleration was as follows.
G=0.58H^0.89
where G: maximum acceleration (multiple of gravity)
H: dropping height (cm)
4. Ethanol accumulation appeared to be due to low oxygen concentration inside the fruit that occured as a result of increase in the respiration rate due to dropping the fruit. The ethanol buildup was accelerated by the lowering of gas permeability caused by waxing treatment. An ethanol content of more than 170mg/100ml caused an abnormal flavour in juice.
5. While sugar content of dropped fruit did not change, citric acidity decreased noticeably during storage for a week. The rate of decrement in case of early ripening fruit and late ripening one was 0.3g/100ml and 0.1g/100ml respectively.
6. As for the dropping practice, late ripening satsuma mandarins were affected more vigorously than the early ripening ones. The limit for the number of drops from 30cm was 20 times in case of early ripening fruit and 10 times in case of stored late ripening fruit. The waxing practice must be avoided in stored late ripening fruit.

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(1) Uniformly ¹⁴C-labeled L-phenylalanine was administered to pepper seeds stored at 1°C and 2°C. Ethanol soluble phenolic acids in seeds were extracted and identified by paper chromatography. L-phenylalanine was incorporated readily into trans-cinnamyl-quinic acid, chlorogenic acid, caffeic acid and an unidentified substance after 6 hours of storage at both 1°C and 20°C. In the seeds stored at 1°C, once-accumulated active cinnamyl-quinic acid and chlorogenic acid decreased rapidly between the 6th and 24th hours of storage while the seeds stored at 20°C did not show such change.
(2) Incorporation into lignin from L-phenylalanine was also estimated, determining the radio activity of alkaline nitrobenzene oxidized product of ethanol insoluble residue in seeds. From the result of this tracer experiment it was found that labeled phenylalanine was incorporated readily into lignin aldehydes of seed at the temperatures of both 1°C and 20°C.
(3) From the above results, it was deduced that the metabolic pathways of phenolic acids in pepper seeds are (i) phenylalanine→cinnamyl-quinic acid→ chlorogenic acid-its oxidized product, brown pigment and (ii) phenylalanine→lignin, and that the former pathway (i) may proceed better temporarily at low temperature than the latter one (ii).

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