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(1)Sci.. Repts.. Nail.. Yokohama. Univ.,. Sec.. IIistological and Embryo. II,. No.. 34, p.. 15-30,. Changes. Cytological. Formation. in. October,. 1987.. During. ●. Aucuba. )aponica. By. Yoshihiko. STA6*. April. (Received. Abstract･ tions. differentiation. When. in cells. electron. value the. R. of other. cells. shortest. was. few. ment. of. frequently cells. of. the. vas. globular. investiga-. cytological The. paper.. embryo. histological. the. and. dif-. tissues. torpedo-shaped. of. cells. of. these. derivatives. of. bypopbysis of. the. And. than. the in. that the. where. polybe. to. seems. celトcycle. that. poly-nucleate. short.. larger. much. duration. the. be. to. seems. vere. the. where. meristem. tissues. and. on. celトcycle. frequently,. of number of plastids to the observations under. ratio. based. ground. protoderm and the duration. most. the. The. calculated. procambium. induced. were. in. And tissues, the value the cells of these of R the where poly-nucleate cell seldom vas epiphysis, to be very low. In these frequency were cells, plastids of division seems the was in number and value stationary throughout the developof R, which lowest. In was the there the cells were embryo, of dormant embryo, among. all. In. medium. induced, the very. the. in the In. presented. the embryo･. R). of. induced,. calculated tissues.. nucleate. the. In. frequently. were. cells. value. microscope.. and. in this. stage of embryo and the dividing become cells poly-nucleate. caffeine, the orientation caffeine for investigating and frequency of the. constructed. (the. 1987). the histological. of heart-shaped. the. at. 30,. body. the. YAMAGUCHI**. with. by. which. mitochondria. from was. in. well. treated. treated. was. embryo. division. obtained. japonica. distinct. delimited. were. development.. of. of Aucuba. became. ferentiated. The. knowledge. The. the embryos. on. Junko. and. the. the plastids developlng. tissues･. cells. of. with. a. body. prolamellar. was. which. in. observed. not. the. any. embryo.. IntrodtlCtion. Unfortunately, very. meager･. gated. by. pollen. development. and. Palm. knowledge at. *. **. Sakata. Kimitsu-gun,. the. Rutger. be. of formation. sac. embryo. Sat6. (1917) and the. and. in. obtained. from. histological. various. stages. of. Hodogaya-ku,. Seed Chiba. Biology,. the. Prefecture,. Sat6. of this. (1971), there the and. japonica are. The future.. near. In this. pollen. of report,. investlgations. cytological. the. on. reports. development. are. investi-. was. species no. Thumb.. on. the the. is presented.. Faculty. Yokohama, Corporation,. Aucuba. development.. embryo by. will. Department. Tokiwadai,. and. studies. embryological. reported. embryo. embryo. the Although. Plant 299-02,. Education,. of 240,. Yokohama. National. Universlty,. Japan.. Biotechnology. Japan.. Center,. Utikosbi,. Sodegaura-machi,.

(2) Y.. 16. SAT(ヨand. J. YAMAGUCHI. Material investigation. (1) Histological Fruits plants. at. in FAA. alcohol. 58-60oC). and. Heidenbain's. iron. alum. dividing. failure does. embryo. at. carefully were. embryos. induced. several. by. under. shaken. in 0.1%. in the. shaken. were丘Ⅹed. FAA. with. at. medium. by. and,. the. investigation. (3) The. embryos. in. aldehyde fixation. 0.2M. was. embedded. in. low. stained. in aqueous. on. and. a. excised. reciprocal. culture. After. shaker. for. that. The. the. medium then. they. histologlCal. examined･. in in. resin lead. and. the an. buffer,. same. ethyl. series. alcohol. (Spurr,. 1969)･.Thin. citrate,. and. which. undergo. 4oC. at. and were. sections. examined. for. with. electron. the. breaking. JEM-100CX.. microscope To. investigate. of dormancy, cultivated. and. dark. 16hr. the. developlng. embryos. MS. the. on. 25oC).. at. into. develop. to. cytologlCal. dormant. were. began. acetate. as. dehydrated. epoxy. viscosity. procedure. tetroxide. osmium were. uranyl. the. site where. fixed in 2.5% (v/v) glutarexcised were buffer (pH 7A), at 4oC for 5hr･ Post-. carefully l%. performed 丘Ⅹed materials. 24hr. of. in the. development. of. the White's. sectioned. cacodylate. sodium in. The. 8hr.. were. which. the. fruits･. for. to. on. were. learn. many. of. orientation distribution. stages. 25oC. by. investigated. several from. 48hr. same. they above, mentioned Cytological investigation. at. at. the. to. order. transferred for. 25oC. vith. poly-nucleate. was. in. solution. stained. The. 1969).. al.,. condition. caffeine were They. (75 cycles/minute).. shaker. sterile. become. treatment. Embryos. place･ a. excised. et. (m･p･. treatment. ca庁eine. (Fig. 1), though. plate. caffeine of development. took. were. combination. by. caffeine. the. stages. frequently. division. cell. were. cell. alcohol. in para氏n. sections. green. (Gim6nnz-Martin. change. cells. body. of. and丘Ⅹed. butyl. tert･. embedded. induced. aqueous. female. University, with. were. The. from. collected. National. fast. cells. with. formation. not. poly-nucleate. treated. cells. were. the dehydration. and. of poly-nucleate. the. of. Yokohama. materials 6/∠m thick･. at. hematoxylin. japonica. After. 丘Ⅹed. the serially. The. and. of the. sectioned. (2). division. a. campus. series,. Distribution. the. of. (formalin-acetic-alcohol).. ethyl. and. the. on. Aucuba. stages. various. growing. Methods. and. Seedling. were. a. changes. These. agal. after starting. the. examined. with. sections. made. electron. a. under. l%. containing. medium. Immediately seedling･. excised. were. which. after. (8hr. sterile condition light at 6000 1ux the. cultivation,. from. the as. microscope. tissues. embryo of the. Ⅶ`ell･. Observation. (1) Development The. body cells. suspensor layer,. that. of was. of embryo early. globular. of inner. consisted. is, protoderm･. embryo. The. inner. which cells cells. attached. covered. of. the. with early. the. at an. apex. of several. embryonic. globular. embryo. surface were.

(3) Embryo. formation. in Aucuba. japonica. 17.

(4) 18. Y.. destined and. system. procambial had. which. just begun. vertically. further,. the. meristems vith. into. cortex. and. pith.. condition. and. hypocotyl-radicle. a was. axis. delimited. radicle. was. formed.. A. Immediately. stage. development,. of. to. the. opposite axis became functional. as. root. tip. which. Many. embryonic. (Fig. 1). Many. division.. of the. Further,. four-nucleate. condition cells. In the. embryo.. infrequently. were. two-nucleate. there. were. portions. had. of the. the. middle. arrangled quently. part. transversely. in. poly-nucleate. cells. of. the. cells almost. ground never. meristems. found. before. the. or. globular four-nucleate. and. formation,. of embryo by. of these cells. part. to. of. most embryo.. the. the. induced. cells, their. before. of. which. attained. occurred. the. stage. frequently. were. epiphysis,. this. procambium. embryo. middle. in. and. At. in the. caffeine. particular,. hypophysis. of. the. the in. laterally,. cells. in the. subsequent. early. of. suspensor･. occurred. at. body. swelling. two-nucleate. infrequently,. three-nucleate. protoderm. the. by. embryo. the. a. process. derivatives. Immediately. were. procambium,. but. three-nucleate. In many strands. of procambial In this embryo, two-nucleate the. japonica. frequently. the. in the. cells. to. not. the. from. away. of development,. stage. of. undergo. attained. throughout. in. three-nucleate. differentiate.. to. condition.. Aucuba. epiphysis,. to. although. (Fig. 3A) cells. meristems. (Fig. 2C).. of the developing. begun. induced. embryo. two-nucleate. situated hypocotyl-. and. two-nucleate,. were. embryo, Throughout. frequently. globular. ground. just begun. of induced.. frequently,. heart-shaped at. the. many. development,. distributed. were. cells r In. treatment･. found,. also. were. this. body. a. already. were. protoderm. in. already. had. which. stages. subsequent it was. pith.. of them. had. nuclei. cells. Two-nucleate. cells. two. embryo. cells more. cells. induced. were. cells. and. These. dormant. the. (protoderm),. of cortex. of poly-nucleate. treatment. both. or. layer. surface. meristems. poly-nucleate. the caffeine one. :. attained dormant. the. beart-. heart-shaped. torpedo-shaped to. of. delimited. primordia. became. and. in. the. the this. hypocotyl-radicle. be. formation,. a. by. pole. the. the. at. and. a. result,. became. to. to. cotyledon. embryo. aplCal. of. to. arise. stainability.. of embryo. The. a. to. embryo. came. stage. process. identified. pole low. epiphysis. developlng. stopped. and ground Distribution. (2). the. cotyledons. further and the. were. follows. The. the. of. embryo. tissues. were. Throughout. elongated. radicle axis Finally, the. apical. juncture. the. As. attained. have. to. the heart-shaped. at. and. embryo. the. at. began. epiphysis.. embryos. of development. between the bases. The. an. the. cells. suspensor. as. in the. obviously. before. few. a. the the. ground. attained. began. near. the. at. them.. of. developed. from. embryo. of cotyledons. and elongation of cells which occurred bypocotyl-radicle to the suspensor axis opposite. (Fig. 2B).. the. till. constituted pair. axis divided. the embryo. obviously formed which. division. shaped. As. pith. (Fig. 2A). embryo. more. actively. and. the embryonic. strand.. hypophysis. divide. to. repeated. be. The. cortex. of. globular. the cells along. procambial. to. came. suspensor. dormant. a. meristems. In the. system.. laterally,. swell. procambium. of. the. into豆round. of vascular. to. differentiated. and. J. YAMAGUCIII. and. differentiate. to. subsequently. a. SAT6. nuclei. freThe. epiphysis.

(5) Embryo. formation. in Aucuba. japan,lca. 19.

(6) 20. Y.. began. to. quently. the√ shoot. constitute. of embryo. In the. hearトshaped. ground. frequently at. meristems. cells. nuclei. whose. cells. found. The. cotyledons･. expanding tissues. of cotyledons. procambial. the. procambial. the. cells. the. transversely. of. in the. preparations. stages. the. were. tissues. the. and. mitochondria. distribution is diagrammatically. arranged. part･. cells gradually. be. It. seems. restricted. within. that, although before dividing. stop. dividing. cells occurred embryos. mature. various. at. cells 4･. in Fig･. shown. cells. its middle. poly-nucleate. of. In the. investigation kinds. various. developing. In. of embryo.. Out. embryos･ our. attracted. between. relations. in the cytoplasm. of organelles. mature. plastids. and. quantitative. The. in. of nearly. examination. the. over. nuclei. to. no. its. two-nucleate. and. they. while,. in. Orientation･. found. because. condition,. histologlCal. development. Cytological. There. for. embryos.. of embryo. (3). the. little. a. procambial. and. of two-nucleate. number. for. dormant. used. dormant. of. the. expanding. to. frequently. the. two-nucleate. all. whose. cells of two-nucleate hypophysis･ the derivatives of. were. attains. cells. came. and. strand. and. ln. its poles. near. were. further,. occurrence. embryo. embryo. and. the. and. at. in the. scattered. variously. two-nucleate. of this embryo, found frequently. were. whose nuclei arranged developed As the embryo decreased. arranged. nuclei. and. hypophysis. were. cells. two-. in. two-nucleate. (Fig. 3C),. embryo of its. derivatives. the. two-nucleate. their. and. strand. longitudinally. in. found. frequently. torpedo-shaped. the. prlmOrdia. In particular,. embryo･. fre-. cell■･ Also,. cotyledon. were. condition. bypophysis. of. two-nucleate. a. the. of. part. longitudinally. In. of this embryo. were frequently. strand. in. dormant. of the. derivatives. the. become. to. induced. middle. arranged. breaking. the. after. division. the. YAMAGUCHI. J.. (Fig. 3B),. nuclear. were. cells. apex. embryo. a. underwent. nucleate. SAT(ヨand. found. were. particular, in. differences. because. organelles. lipid globules. addition,. in. organelles,. attention,. two. these. the. of. of cells constitutlng. distinctively. various. among. occurred. the. within. the. in. less. embryo.. Mitochondrion. (a) Both. mitochondrion. differentiated. condition.. in. embedded entiated. inner. the. proliferate. They. were. regarded. the. and. low.. as. were. inner. a. a. a. plastid. about. of the. of the. system. only. The few. a. was. mitochondria. well･. had. still. were. embryo. differentiated. not. is, proplastids. least. differformed. vesicles. and/or a few single thylakoid-like thylakoids which plastids (Fig. 5B) had. envelop. of granum. which. had. just begun. to. be formed･. of differentiation chloroplast, thoughthe degree In a or frequently grains･ contained starch grain. young. than. more. starch in. cells. membrane. did. thin stacks. embryo,. and only. it. that. plastids. contained. procambium. gtJains. and. The. torpedo-shaped. meristems. The. in. slightly differentiated. to. very. plastid. of. membrane. began. was. and. (Fig. 5A),. The. structures.. plastid. and. stroma. poor. plastids. from. and. the. half of the plastids. grains, though, derivatives of hypophysis,. grain. 20 percent. or. of all plastids. in. contained. in. cells. cells. of the. of the. ground. epiphysis. with starch plastids in these ce11さ･.

(7) Embryo. formation. in Aucuba. 21. japon,lca. ○. 卒ヽ. ヽ ′. ￠. 恥. 8 0. 匂.. ○℡. ′ ′. (eo甲■中e 1. (b. ､缶. ○. l. 0?. A). Qt. ′. ′′. B. q)q?. o. 8. BB. 1. l. 血. ヽ-ヽ. (p. 'cB1.tb. ヽ ■. ヽ. l. A. ○. :. ■. ヽ. / ′ ′. c丸.:. B. ′. ヽ. ′. ヽ_. C. 8. A. 8. e88 e. /. 8. ､----ノ. e8. 8. B. B. 令. p8. 0 1/. :.ttL. l. /. J ∫. L l. l. l l. ㌔. e/′. I. 8､ 8. Q). 8. 8. 8′. ､Q. q)_tpむ匂. 専一. 8管-呑. ___･･. _i__e__Q_‥_. Jd. 叫ノ. CIC, 8. ￠. 史l. l ′. J. I. l. ′や. ノ. 1. .Je. L. 二￠8 ,/'￠ CEl. 8. 8I､､. 1 1. ∫. ￠ム￠. 1 J. 1. 8. ∫. ￠. ヽ I. l￠ l. 1 1. 8J. ヽ. I. ヽ. .1. l. 8. 88. )1. 1. 8･:.8. e. l. 1. 8. ･さ￠. E. D = 100. Fig.. Diagrams. 4. feine B･. Globular. E.. Embryo. Cells. between. the. followlng. and. plastids. equation. of. number to. embryos means some. of R.. that. obtained cells. of. their. along. axes. mitochondria. Torpedo-shaped. embryo.. dormant. condition.. In. (without. plastids And. counted.. of mitochondria. caf-. embryo.. were丘1med･. and. was. No.. No.. was. of plastid. then,. calculated. the. the. pboto-. distinctio･n. (R) of. ratio. to. according. the. simply. each. ×100. of mitochondria. in cells of calculated in Table 1. The shown. are. to. by. A･ Eal･1y globular D･. embryo･. induced. cells. division･. :. of R. values. poly-nucleate. of. attainment. chloroplasts). R=. The. before. sectioned. 11m. of cell. C･ Heart-shaped. were. proplastids of. and. immediately. the. number. orientation. embryo･. which. micrographs,. distribution. showing. treatment. ≠. each. by. adding. all the. tissue. and. dividing. tissue. of individual the. by. values. sum. the. constituting R. shown values. the. in. of number. Table R. developlng. 1. are. the. calculated. of the. values. in.

(8) 22. Y.. SAT6. and. J.. YAMAGUCIII.

(9) Embryo. tIS.. ｡ -,. ､･′′.蛋. <喜i覆. ･. ･､玩′-. formation. in Aucuba. japonica. 23. F/.垂萱. 璽i､,寧.

(10) 24. Y.. SAT6. and. J.. YAMAGUCIiI.

(11) Embryo. At. stage. each. of the. protoderm. ground. and. those. of other. tissues,. values. of the. procambium. ably. the. that. values. considerably. very. small,. equal. in number. while. the. larger. than. to. is. larger. the. those. in. the. the. R. of. the. extreme. in. (4.0-6･0) and. ground. of R･. small. plastids. and. And,. remain. But. almost tissues,. other in. the. is extremely. in. the. the. epiphysis. ground. other small. (35･0). meristems. (1･5｢2･0) epiphysis (7･0-15･0)･ This causes. in. the. the. epiphysis, any. at. unchanged. is. embryos･ are. and. always. meristems in the. are. (弧0) is much. of hypophysis. in number. seems. embryo. globular. procambium. (20･0-30･0) and fewer. value. the. it. development･. the. of mitochondria. number. of. of procambium hypophysis and. of. consider-. hypophysis. cells. (Fig･ 7A). epiphysis. are. torpedo-shaped. and. derivatives. is much. of mitochondria. of R. than. The. And. meristems･. embryo. of. cells. protoderm. plastids. protoderm. the. in. the. The. in. that. (10.0-25.0), while. number. in. in. derivatives. the. of. value. of hypophysis. of. cells. larger develops･. embryo. derivatives. its value. 3･5-4･0). mitocholldria. examined.. than. epiphysis. process. is. number. (30･0-35･0). that. embryos. in. the. in. calculated. considerably. the. that in the heart-shaped. the. of. Also,. the. and. because. with. number. tissues.. procambium. throughout. compared. (of which. in. the. of. are. as. ground. and. R. of. derivatives. protoderm. is interesting,. procambium. than. R. of. increases. value. of the. values. (Fig･ 6A). (Fig. 6B) and. stationary. the. plastids. the. 25. jaPonica. the. meristems. and. those. than. smaller. development,. embryo. of. in Aucuba. formation. respective Of embryo. stages. development.. In Table the. and. 1,. of the 44.9,. and. the. of. apical. respectively･. of expanding. part. the. value. which. selected. in the. 52.6,. and. 1.. 1, also,. embryo. is 71･3･. by. of. number. embryo. Protoderm Meristem. Der.. Epiphysis *. Derivatives. of. phypophysis･. the ground. ground. much. lower. averaglng. Values. of R. protoderm. and. ground. of plastids. to. number. Heart-shaped embryo. of. at. the. decreased. of pith. meristem. apical 5･1. meristems only. calculated. of R than in cells calculated value. meristems. mitochondria･ Torpedo-shaped embryo. 51.9. 79.3. 26.1. 35.5. 71.3. 24. 1. 22.4. 19.7. ll.3. 6.0. 4.4. ll.2. Hypo.*. values. with. they. embryo,. were. 30. 5. 8.0. Procambium. at. the. of the. protoderm. of R of the. the values. respectively･. of the cotyledon. meristems･. ground. percentages. of. the. at. torpedo-shaped. But. 79･3,. and. the protoderm. at. only. is, cells. simply. cells. whole. Globular. Ground. and. That. obtained. and. protoderm. the. In Table. cotyledons. from. randomly. Table. of. respectively･ was. and. embryo. 51･9. heart-shaped. of the. protoderm. as. only. calculated. cotyledon. expanding. the. shown. are. were. heart-shaped. torpedo-shaped. 30.7. to. the. of. in. calculated. embryos. the values. when. primordia. of R. values. torpedo-shaped. However,. part. the. occur.

(12) 26. Y.. The. young. embryo,. oping. found. dormant at. of these. least. at. of the. cells not. chloroplasts. the. only. chloroplasts. occurrence. embryo. of. body. the. with. plastids. of. a. a. the. but. (Fig. 7B), developlng. in the body. prolamellar. Some. cells.. body. in. were. chloroplast. found. not. deveト. of. But,. in these. prolamellar. were. with. as. found. were. bad. cells. development.. differentiated that. proplastids. in the. proplastids stage. plastids. in the dormant. or. the. with. torpedo-shaped. embryo,. proplastids. proplastids The embryo.. till the. YAMAGUCflI. J.. and. coexists. It was. all.. the. SAT6. be. to. seems. (. feature. in. (b). Lipid. globule. The. number. distinct. as. counting. the. of. Tbe. development. to. from. japonica.. as photomicrographs The plastids. numbers. and. heart-shaped. tissues to. globules developlng. On. the. in. was. the torpedo-shaped. the. number. hand,. the. procambium. the. it. stage. was. of lipid globules The number of. number. and. protoderm. Although. become. to. seems. found. among. almost cell. tissues. uniformly of embryo.. began. to. actively the. decrease. cultivation. in the. dormant. After. the. rapidly. developing on. developing. of the. the. embryo. breaking. which for. medium. Table. 2.. Globular embryo. Protoderm Ground. Meristem. Procambium Der.. Hypo.*. Epiphysis *. Derivatives. of. bypophysis.. and a. of. there. and. seedling. embryo,. globules. were. about. stationary. The. globules. the. number. in each. any. cells embryo. (Fig. 8).. of. lipid. globule.. Heart-shaped. was. lipid globules. the. dormant. stage. distributed. were. in. the. at. globules. 25 globules. condition, from. obtained. 40 days. Numbers. lipid. the. not. lipid. of the. ､･dormant. were was. there. and lipid. development.. of embryo. and ground meristems. distinct difference in distribution. the. lipid. of. delimited had just begun more to be of epiphysis which obviously heart-shaped but lipid at stage many the torpedo-shaped contain globules, be lipid to decreased the number globules of remarkably similar to the the. are. In the. tissues.. actively,. development.. large. not. of both. cells. other. the embryo. with. those in. cells. in. well. its change accompanied in the ground meristem.. and. to. hypophysis. of the. of these. protoderm. similar. which both tissues.. in. accompanied. in cells. in the. was. derivatives. the. the. mitochondria. lipid. many. embryo. in its changes globules. Aucuba. from. counted. were. considerably. decreased. similar. of. lipid globules. embryo. torpedo-shaped globules. was. at. embryo. in. 2. of. were. dormant. of the. number. number. the. with There. cells. lipid globules. of. in Table. shown. the. least. Torpedo-shaped. embryo. embryo. 7.3. 29. 0. 16.3. 15.5. 25, 3. 20. 2. 3.0. 5.0. 5.7. 1.0. 4.0. 3.2. 49.0. 19.7. of. an. by.

(13) Embryo. in. formation. Aucuba. 27. japonica. 30. 20. α: l⊥l 〔EI. ≡: = ≡. t). 10. 2O. 30. ⊃AYS. Fig.. 8.. OF. Disappearance breaking. 40. lipid globules. of. dormant. the. of. 50. CUしTIVAT10N. after. condition.. Discussion The. site. distribution early. of. poly-nucleate. embryo,. In particular,. nucleate conditions. dermal cells is shorter And,. protoderm. for. heart-shaped place. torpedo-shaped hypophysis meristem further,. The. poly-nucleate. with. that. at. and. duration. the of with. near. cells. any two. the. other. the. provide. As. the. cells. in. and. development･ cells. the. ground. derivatives. of. continue. to. However,. long,. the This. of epiphysis･. is very. of. develops. embryo. bypophysis. of. early. derivatives. division. of. of. poles. In the. the. and. of cells of epiphysis. protodermal. and after the frequently takes. and near infrequently.. in the. of the. to. at. procambial derivatives. proto-. before. low.. of embryo. the. preparation. cotyledons. is induced. of cell-cycle. compared. cells.. nuclei apices. and. process. never. almost. divide. becomes. the. a. division. cell. frequency. the. though. be. Immediately the. of expanding. the. throughout. condition. that. cells. the cells. by. the. layer. a. in. induced. it is inhibited. of hypophysis. procambial. frequently. shows. but. part of embryo middle division is restricted in. the. hypophysis. divide. cells.. in. of celトcycle. to. the. the .In throughout the embryo to threeattain and four-. surrounded. considered. the. at. cells. from. treatment･. caffeine occur. cells duration. development,. divide,. frequently. are. of embryo,. the. frequently. inner. of the. embryo. embryo,. inner are. cells. derivatives. the. in. These. part. middle. though. embryo. of. the. is inferred. place. induced. protodermal that. that. of volume. stage. the. at. than. embryos.. increase. an. shows. two-nucleate. developing. cells of. of. This. by. cells. the. some. take. induced. cells. poly-nucleate. globular. body.. frequently. divisions. cell. where. which of. the. arrange procambial. longitudinally strands. were. of the. frequently developing. found embryo,.

(14) 28. Y.. not. of. two. cells with frequently,. and,. division. cell. remains. in two-nucleate. that. of nuclei. and. as. is not. increases. in. Based. the. on. follows:. and. derivatives. ably. the. as. they. are. value. R. of. R,. dermal. the. value. these. cells. tissues. which. from. this. elongates. at. embryo. are. an. constructing meristem,. arrangeits. poles. system In cells. tissues.. classi丘ed. procambium 1, the. value. it increases. and. Group. as. classified. ground. 2;. In Group. Groups,. two. and. Group. epiphysis.. tissues. torpedo-shaped. and. nuclei. developlng. a. an. of. remarkdifferentiate. i adult. of these. body,. plant. tissues, therefore,. in multiplicatio□. But, cells which have smaller occur in in Table 1 the shown cotyledons expanding. mitochondria the. with. their. of in. division. cell. treated. part.. other. photosynthetic. arrangement. It is considered. ground and Group 3; and. with The. an. is. cell. principally,. tissues. system. torpedo-shaped. in. induced. its middle. at. of. actively than. of the. pith. strand,. compared. hearトshaped. of the. procambial. 1; protoderm. a. surpass. plastids. caffeine.. develops･. into. princlpally. and. with. value. embryo. of. treated. thickness. large. is,. orientation. observed, although The orientation. strand.. dividing. That. 1969).. al.,. of hypophysis,. is very. of R. if the. even. was. procambial. the. the. Group. the. of. shows. cells. which. embryo. part. unchanged, et. transversely. arrange. middle. (Gim6nnz-Martin. caffeine. ment. the. J. YAMAGUCHI. and. which. nuclei. in. SAT6. embryos And. embryo･. in. and. the. two-nucleate. a. ground. of meristem is frequently. condition. by. lS, the caffeirle treatlnent. That in the young daughter has Just been formed by the division cells which surpass of cell, mitochondria In Group 2, the value R is plastids in multiplication. medium value of of and it is almost least at development. stationary after the globular stage of embryo. In these throughout. the. frequently. that. plastid. the. globular. is. The. condition. 1984). may. seldom. epiphysis lt may. never. and differentiates be summarized. is high,. value. while. is small. epiphysis. maintains. investigation. present. of. very tissues,. multiplication in differentiated the. near. value. the. undifferenti(Natesh and Rau,. development. of embryo. the. cells. it is. and. are. ours.. Two-nucleate. in cells of epiphysis. Therefore, 1t Seems And, the the number of mitochondria development. throughout the process of embryo. that. division.. procambium. japonica, the. general,. process. owing is induced. unchanged. the. the. of R. value. root,. and. of these. cells. mitochondrion has Just which. procambium. in. in. seems,. division,. cell. the. to. undergo. remains. that. division. throughout. almost. cells. Aucuba. view. be supported. condition. among. system. poly-nucleate. It. treatment.. In the. that,. Vascular. development,. embryo. however,. Into. princlpally. caffeine. maintained. embryo,. ated. seems. of the. multiplication.. of epiphysis･. plastids. by. induced. and. the. process. balance. a. di庁erentiate. remains later. than. undifferentiated the. follows;. as. of. an. R. the value. is. ground at least in. small. is large. condition. where. in cells where. the. the. It to. the. of. cell. similar. does. meristem in the developing. cells. and. embryo. frequency. frequency. of. of division. islow. As. the. lipid, it may. lipid globules be. understood. have that. been. considered. the globules. as. occurrlng. a. kind ln. of. form. storage. all cells. of. a. dormant. of.

(15) Embryo. the. from. disappear. embryo. developlng. the. where. cell. development. body. plant. in. embryo. in. a. cells. the. dormant. have. some. is common. points. in. the. cells. of embryo investigation. further. in. cells. of epiphysis. dormant. of the. cells. occurrence. base. the. body. the. the. on. endosperm prolamellar. cells. of dormant. just. mentioned. meristem. a. 1984).. a. with. because. plastids leaf. (Wellburn,. well-developed. of plastid. near. of the. of light. in. is embedded. the cells. in. process. in the. at. interesting,. to. few. the. although､. meristem the low intensity. very. be. seems. plastids with a prolamellar & Meier, 1984). The. the. the. It. Seedling.. may. body. the. are. japonica. embryo. small,. Lichtenthaler. Thus,. fruit wall.. red. throughout. are. there. under. of Aucuba. place. prolamellar. near. is cultivated. embryo. by. a. that. globules. of lipid globules. (Sch】1epe, 1980;. which. enclosed. known. occur. dormant. of R. 29. developlng. lipid. the. takes. with. jaPonica. actively. behavior. the. plastids. leaves. body. the. body. to. It is well. in etiolated. well. the values. where. the. are. embryo･. The. frequently. in Aucuba. an. of that. as. division. in regard. There. with. all cells. embryo. and. is required. formation. above.. 摘. 要. アオキの腫形成過程における組織学的及び細胞学的研究から得られた結果について報告した｡肱本体中の組織学的分化は球状旺からみられほじめ, --ト形腫,水雷形腫に発達するにつれて複雑化し,各組織ほ明瞭に識別できるようになる｡分裂中の細胞をカフェインで処理すると多核性の細胞が誘導できる｡そこで,腫の発達と細胞分裂の頻度や方向を知るために,匪をカフェインで処理した｡また,発達中の旺の各組織の電子顧徴鏡的な観察からミトコンドリアの数に対する色素体の数の割合(形, R値)を計算した.原表皮と基本分裂組織でほ,多核性の細胞がよく誘導されて, 細胞分裂がよく起こるものと推論される｡また,この両組織で計算されたR値は他のどの組織よりも大きい値を示した｡前形成層と原板端が作りだした幼板でほ,もっともよく多核性細胞が誘導され,発達中の経ではもっともよく細胞分裂が起こっていると推論できるo また,ここではR値は原表皮や基本分裂組織の値よりもかなり低い値である｡原茎頂の細胞が多核化することは殆どなく, この細胞の細胞周期はきわめて長いものと思われる｡また,色素体の数ほ極端に少なくR値は旺形成のどの時期でもはぼ同じで,どの組織の値よりも極めて小さい｡休眠中の旺を構成している細胞には,発達中の腫の細胞にはみられない,プロラメラ･ボディーを持つ色素体がしばしばみられた｡ References GIM丘NEZ-MARTiN, 34:. G.. LICHTENTIIALER, by. H. K.. light. for. Press,. Univ.. S. and B.. bot.. SAT(ラ,. Y. to. Kinetics. M.A.. 1971.. D.. MEIER,. light. and. RAU,. binucleate. of. RuTGER,. production. by. caffeine.. Cytologia. biology,. Regulation In. Series. Seminar. The. In. embryo.. Springer-Verlag, 1917.. The. of. chloroplast. R.∫. Ellis. B.M.. photomorphogenesis biogenesis. (ed.), Cbloroplast 21). pp. 261-281. Johri. Cambridge. (ed.), Embryology. of. Berlin. of Aucuba. embryology. japonica.. Rec.. Tray.. 119-126.. Embryological. unusual. 1984. quality.. 1984.. 377-443.. pp.. and A.A.L. Neelリ14:. the. and. experimental Cambridge.. Angiosperms. PALM,. 1969.. al,. intensity. (Society NATES甘,. et. 29-35.. development. (Biol.), 35: 20l-206.. in. study. of. Aucuba the. embryo. japonica sac.. Thumb., S°i, Rep.. with. T6hoku. special reference Univ. Ser. ⅠⅤ.

(16) Y.. 30. ScHNEPE,. E.. Reinert SpuRR,. 1980.. SAT(ヨand. J. YAMAGUCHI. Their of plastids: Chloroplasts (Results and (ed.),. Springer-Verlag, Berlin. pp.ト27. A.R. 1969. A low-viscosity epoxy scopy.. WELLBURN,. Journ. A.R.. development. Types. Ultrastruct. 1984.. Resリ26. Ultrastructural,. :. problems. resin 31-34.. embedding. resplratOry. development. Baker In N.R. vith cbloroplast 253-303. EIsevier, Amsterdam. biogenesis. pp.. interconversions.. and. in cell. and and. differentiateion.. medium metabolic. ∫. Barber. for. electron. changes. In Vol.. J. 10),. micro-. associated. (ed.), Cbloroplast.

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