1954 317

Karyotaxonomy in Poaceae II. Somatic chromosomes of some species* TuguoTateoka NationalInstitute of Genetics,Misima

Received March 5, 1954

Introduction

A previous paper (Ono and Tateoka 1953) dealt with the somatic chromo somes of thirty two species and varieties belonging to Poaceae. In the pre sent paper, the results of the studies on the somatic chromosomes of fifty three species in the same family are reported

Material and method

The plants used were collected in the fields. Localities are as follows:

Kakunodate in Akita-ken, Suginami, Meguro, Musasisakai, Koremasa and Okutama in Tokyo; Hakone in Kanagawa-ken; Misima, Syuzenzi,

Makinogo, Mt. Amagi and. Heta in Sizuoka-ken; Mt. Nyugasa, Aoyagi, Mt.

Senzyo, Kamikoti and Mt. Yari in Nagano-ken. For the chromosome studies, the root-tip cells were always used, and they were fixed directly in the field by Navashin's solution. Paraffin sections were cut at 10-15 micra and

Newton's gentian violet method was used for staining. All the figures were drawn with an Abbe drawing apparatus at a magnification of 20•~100.

Observations

Table 1 lists the species, the chromosome numbers, the localities of col lection and the names of investigators. 1) Trib. Bambuseae

Sasamorpha purpurascens Nakai Fig. 2, Pleioblastus chino Makino

Fig. 1.

In both species, forty eight chromosomes of medium or small sizes are counted, as in many other species observed by Uchikawa (1953).

2) Trib. Hordeae

Agropyron ciliare Franch. Fig. 3, Elynzus sibiricus Linn. Fig. 4.

Twenty eight chromosomes are counted in both species, and they are of large sizes. The author also observed the somatic chromosomes of Brachypo dium sp. obtained in the northern India. It shows eighteen small chromo somes, like B. sylvaticum found in Japan (cf. Ono and Tateoka 1953)

* Contributions from the National Institute of Genetics, Japan, No. 70. 318 T. Tateoka Cytologia 19

3) Trib. Bromeae Bronurs japonicas Thunb. Fig. 16. Fourteen chromosomes are observed in somatic cells and their sizes are as large as those of Agropyron, Elymus, Horcicum, Triticum, etc. 4) Trib. Agrostideae (including Trib. Aveneae; i.e. Ohwi's Subtrib. Aveninae)

Figs. 1-15. Somatic chromosomes. 1, Pleiohlastus chino. 2, Sasamorpha purpurascens. 3, Agropyron cilia cc. 4, Elgnrus sihiricus. 5, Phleum pratense. 6, Calamagrostis arundinacca var. brachytricha. 7, Calamagrostis Langsdorffii. 8, Calamagrostis Epigeios. 9, Calamagrostis hakoncnsis. 10, Alopecurus japonicus. 11, Trisetum spicatum. 12, Beckmannia Syzigachne. 13, Kneleria cristata. 14, Deschampsia flexuosa. 15 Helictotri chon. Hideoi. 1954 Karyotaxonomy in Poaeeae II . 319

Calajnagrostis arundinacea Roth . var. brachytricha Hack. Fig . 6, C. hakonensis Fr. et Sav. Fig . 9, C. Langsdorffii Trin . Fig. 7, C. epigeios Roth. Fig. 8, Alopecurus japonicus Steud . Fig. 10, Phleuna pratense Linn . Fig. 5, Helictotrichon Hideoi Ohwi Fig . 15, Koeleria cristata Pers. Fig. 13, D eschaanpsia flexuosa Trin . Fig. 14, Trisetzena spicatum Richt . Fig. 11, Beck mannia Syzigachne (Steud .) Fernald Fig. 12. Except Koeleria cristata , the other species all show polyploid numbers of seven, and the large chromosome size. In Koeleria, cristata, sixteen chromosomes are observed in somatic cells , and among them, two chromo somes are very small in comparision with the other sisters of the same nuclear plate. These small chromosomes have submedian constrictions and are found in all plates observed. They may be supernumerary chromosomes , judging from the small size and especially the basic number of the genus Koeleria and its related genera. Beckmannia Syzigachne shows fourteen large chromo somes, one pair having satellites and subterminal constrictions , six pairs hav ing submedian constrictions. In Aloprcurus japonicas , Deschaurpsia flexuosa and Trisetunz spicatum, twenty eight large chromosomes are found , Phleum pratense showing a hexaploid number, and Helictotrichon Hideoi a diploid number. In Calamagrostis arundinacea var. brachytricha, hexaploid (2n=42) and octoploid (2n=56) are found, though C. arundinacea s. str. was reported only as tetraploid by Nygren (1946), Avdulov (1931), etc. Sixty four individuals are observed up to the present. Localities where they were obtain ed are as follows; Okutama, Musasisakai and Suginami in Tokyo; Hakone in Kanagawa-ken; and Misima, Heta, Yugasima-Mt. Amagi in Sizuoka-ken. In total, twelve individuals are octoploid and fifty one are hexaploid, and one individual obtained at Musasisakai showed 2n=51. Ecological and distribu tional differences between octoploid and hexaploid can not be found so far as the author's observations indicate. In C. hakonensis, tetraploid (2n=28) and octoploid (2n=56) are found. Among fifteen individuals observed, twelve individuals obtained in Hakone are all tetraploid. Two individuals obtained at Kakunodate in Akita-ken and one individual obtained at Kamikoti in Naga no-ken are octoploid. C. Langsdorffii obtained at Mt. Nyugasa, a closely related species to C. purpurea (2n=56-91 Nygren 1946), shows twenty eight chromosomes. C. epigeios obtained at Makinogo, among which various polyploids were found, shows a tetraploid number. 5) Trib. Stipeae Milium effusum Linn. Fig. 17. Twenty eight chromosomes are counted and their sizes are large, in ac cordance with the Hunter's (1934) observation. 6) Trib. Phalarideae Phalaris arundinacea Linn. Fig. 18, Anthoxanthum odoratum Linn. Fig. 19, A. japonicum Hack. Fig. 20, Hierochloe odorata Beauv. var.

Cytologia 19. 1954 21 320 T. Tateoka Cytologia 19 pubescens Kryl. Fig. 23, H. alpina Roem. et Schult. Fig. 21. Two species of Anthoxanthum observed are polyploids of the basic num ber of five; A. odoratum, twenty and A. japonicum, seventy. In Phalaris arundinacea twenty eight chromosomes are counted, as in the observations

Figs. 16-27. Somatic chromosomes. 16, Bromus japonicus. 17, Milium effusum. 18, Phalaris arundinacsa. 19, Anthoxanthum odoratum. 20, Anthoxanthum japonicum. 21, Hierochloe alpina. 22, Dactylis glomerata. 23, Hierochloe odorata var. pubescens. 24. Festuca parcigluma. 25, Festuca ovina var. supina. 26, Fcstuca rubra var. pacifica. 27, Cinna latifolia. of previous investigators. Hierochloe alpina, obtained at Mt. Senzyo, shows an octoploid number (2n=56), coinciding with Flovik's (1938) observation in the materials of northern Europe. In H. odorata var. pubescens, forty two 1954 Karyotaxonomy in Poaceae II. 321 chromosomes are counted. Chromosomes of all species observed show large sizes, as in those of other species observed by previous authorities. 7) Trib. Festuceae Poa annua Linn. Fig. 28, P. acroleuca Steud. Fig. 29, P. nipponica Koidz. Fig. 30, Dactylis glomerata Linn. Fig. 22, Cinna latifolia Griseb. Fig. 27, Festuca parvigluma Steud. Fig. 24, F. rubra Linn. var. pacifica Honda Fig. 26, F. ovina Linn. var. supina Hack. Fig. 25. All of the species observed are polyploids of the basic number of seven, and most of the chromosomes are of medium or large size. In Poa annua, two individuals observed show twenty eight chromosomes; two pairs of large and J-shape, and the other twelve pairs of medium or small V- or J-shaoe. In P. acroleuca, six individuals are observed and all show twenty eight chromo somes, of which one chromosome has a long secondary constriction and a submedian primary constriction. An individual of P. nipponica obtained at Misima has forty two chromosomes, while Moriya and Kondo (1950) reported n=28 in the material of Utunomiya. Dactylis glonierata shows twenty eight chromosomes as was observed previously by Muntzing (1937), Felforldy (1940), etc. In Cinna latifolia, twenty eight large chromosomes are found. Festuca parvigluma shows twenty eight chromosomes, in which one pair of J-shape and many pairs of V-shape are observed. In Festuca rubra var. pacifica, an individual obtained at the seaside in Heta shows a hexaploid number, and an individual of F. ovina var. supina obtained at the alpine belt of Mt. Sen zyo has a tetraploid number. 8) Trib. Meliceae Melica nutans Linn. Fig. 32, M. Onoei Fr. et Sav. Fig. 31, Tor reyochloa viridis (Honda) Church Fig. 34, Glyceria acutiflora Torr. 33, G. ischyoneura Steud. Fig. 35, G. lithuanica Lindm. Fig. 37, G. alnasteretum Komar. Fig. 36. In the two species of Melica, ML nutans and M. Onoei, eighteen chromosomes are counted. Torreyochloa viridis obtained at Kakunodate in Akita-ken shows twenty one large chromosomes (triploid) in somatic cells. In Glyceria acutiflora obtained at Misima, twenty chromosomes are counted while Church (1949) reported 2n=20 in the materials obtained in the United States. In G. ischyoneura, 2n=40, and in G. alnasteretumn and G. lithuanica, 2n=20 are counted. Their chromosomes are of small or medium size. 9) Trib. Phaenospermeae Moliniopsis japonica Hayata Fig. 40. Fifty chromosomes are observed in somatic cells. 10) Trib. Arundineae Phraginites japonica Fr. et Sav. Fig. 38. Forty eight small chromosomes are observed. The author also observed the somatic chromosomes of P communis obtained at Misima, which show ed 2n=ca. 96. 21* 322 T. Tateoka Cytologia 19

11) Trib. Oryzeae Leersia oryzoides Swartz. Fig. 39. Forty eight chromosomes are observed in somatic cells. 12) Trib. Chlorideae

Figs. 28-47. Sematic chromosomes. 28, Poa annua. 29, Poa acroleuca. 30, Poa nipponi ca. 31, Melice Onoei. 32, Melica nntans. 33, Glycerin acutiflora. 34, Torreyochloa viridis. 35, Glyceria isclryuneura. 36, Glyeeria alnasteretum. 37. Glyceria lithuanica. 38, Phragmi 1es japonica. 39, Leersia oryzoides. 40, Moliniopsis japonica. 41, Cynodorr Dactylon. 42, Erairostis ferruginea. 43, Eriochloa rillosa. 44, Panicum bisulcatum. 45, Echinochloa Crus-galli. 46, Setaria ciridis. 47, Isachne glohosa. 1954 Karyotavonomy in Poaceae II. 323

Cvnodon Dactylon Person Fig. 41, Eragrostis ferruginea Beauv. Fig. 42. In the former, forty chromosomes are found, and among them eight are very small in comparison with the others. In the latter, eighty small chromo somes, including one pair of Sat-chromosome, are observed. 13) Trib. Arundinelleae Arrnrdinella hirta Tanaka Fig. 48. Fifty six chromo somes are observed in somatic cells, while Moriya and Kondo (1950) reported n=14 to the material obtain ed at Utunomiya. The chromosomes are all small. 14) Trib. Paniceae Echinochloa Crus galli Beauv. var. cau data Kitagawa Fig. 45, Eriochloa villosa Kun th. Fig. 43, Panicum1 bisulcatum Thumb. Fig. Figs. 48-53. Somatic chromosomes. 48, Arumrdinella hirta. 44, Setaria viridis 49, Miscanthus sinensis. 50, Arthruron hispidus. 51, Impera Beauv. Fig. 46, Isach ta cylindrica var. Koenigii. 52, Themeda japonica. 53, Microstelium japonicnm. ne globosa O. Kuntze Fig. 47. All of the species observed show small sizes of chromosomes, anct poiy ploid numbers of nine or ten; Echinochloa Crus-galli var. caudata, 2n=54; Eriochloa villosa, 2n=54; Panicann bisulsatum, 2n=54; Setaria viridis, 2n =18; Isachne globosa, 2n=60. While Avdulov (1931) reported tetraploid in Panicunz bisulcatum, the individual observed by the author is hexaploid. 15) Trib. Andropogoneae Imperata cylindrica Beauv. var. Koenigii Dur. et Schinz. Fig. 51, Miscanthus sinensis Anders Fig. 49, Microstegium japonicum Koidz. Fig. 53, Arthraxon hispidus Makino Fig. 50, Theineda japonica Tanaka Fig. 52. The species reported in the present paper show small or medium sized chromosomes and their numbers are polyploids of ten or nine; Imperata cylindricaa var. Koenigii, 2n=20; Miscanthus sinensis, 2n=40; Micr-ostegium japonicum, 2n=20; Arthraxon hispidus, 2n=36; Themeda japonica, 2n=80.

Consideration

Taxonomic information obtained from the above observations will be set forth coherently in later papers. In the present paper, some information 324 T. Tateoka Cytologia 19

Table 1. List of chromosome numbers reported 1954 Karyotaxonomy in Poaeeae II. 325 326 T. Tateoka Cytologia 19 1954 Karyotaxonomy in Poaceae II. 327 concerning the genera Milium and Torreyochloa will be briefly brought out bellow. In spite of the fact that the genus Milium is included in the tribe Stipeae, which is supposed to have small chromosomes, those of Milium are large, difference being so great that phylogenic difference must be considered. Thus, further investigations are required although this taxonomic placeing of the genus Miliuann is supported by many taxonomists on morphological bases. Church (1949) established a new genus Torreyochloa, differing from the genus Glyceria on the bases of chromosomal, morphological and anatomical characters. Of Glyceria found in Japan, two species, i.e. G. viridis and G. natans, may be transferred into Torreyochloa (Church l. c.). According to Church the somatic chromosomes of Torreyochloa are characterized by the basic number of seven and comparatively large sizes, while those of Glyceria have the basic number of ten and small sizes. In the present work, the somatic chromosomes of four species of Glyceria and one of Torreyochloa were reported. In accordance with Church's statement, the chromosomes of Torreyochloa (T viridis) showed the basic number of seven and larger sizes in comparison with those of Glyceria. As morphological characteristics which differentiate Torreyochloa from Glyceria, Church offered the following ones; number of nerves of 2nd glume; lemma apex; palea apex; shape and matter of lodicule; stigma branching; shape, hilum and apex of caryopsis. Further more, Church (l. c.) offered the cell patterns in the leaf epidermis as anatomical characters. Considering the status mentioned above, the present author supports Church in opinion.

Summary

1) Somatic chromosomes of fifty three species in Poaceae were report ed (Table 1, Figs. 1-53). 2) In Koeleria cristata, supernumerary chromosomes were observed. 3) In Calanzagrostis arundinacea var. braehytricha and C. hakonensis, intraspecific polyploidy was found; in the former, hexaploids and octoploids; in the latter, tetraploids and octoploids. 4) The karyotypic differences between two closely related species Poa annua and P acroleuca were mentioned. 5) The taxonomic problem of the genus Milium was considered. 6) The genera Torreyochloa and Glyceria were discussed from a karyotaxonomic standpoint. I wish to express my cordial thanks to Dr. Y. Takenaka, Dr. H. Ono and Dr. J. Ohwi who gave me various valuable advices during the course of the present investigation. 328 T. Tateoka Cytologia 19

References

Avdulov, N. P. 1931. Karyo-systematische Untersuchung der Familie Gramineen. Bull. Appl. Bot. Pl. Breed. Suppl. 44: 1-428. Brown, W. V. 1950. A cytological study of some Texas Gramineae. Bull. Torrey Bot. Club 77: 63-76. - 1951. Chromosome numbers of some Texas grasses. Ibid. 73: 292-299. Church, G. L. 1949. A cytotaxonomic study of Glyceria and Puccinellia. Amer. Jour. Bot. 36: 155-165. Darlington, C. D. and E. K. Janaki Ammal 1945. Chromosome Atlas of Cultivated Plants. London. 397 pp. Flovik, K. 1938. Cytological studies of arctic grasses. Hereditas 24: 265-376. Hunter, A. W. S. 1934. A karyosystematic investigation in the Gramineae. Canad. Jour. Res. 11: 213-241. Krishnaswamy, N. 1940. Untersuchungen zur Cytologie and Systematik der Gramineen. Beih. Bot. Zbl. 60: 1-56. Maude, P. F. 1940. Chromosome numbers in some British plants. New Phytol. 39: 17-37. Moffett, A. A. and R. Hurcombe, 1949. Chromosome numbers of South African grasses. Heredity 3: 369-373. Moriya, A. and A. Kondo. 1950. Cytological studies of forage plants. I. Grasses. Jap, Jour. Genet. 25: 126-131. Nygren, A. 1946. The genesis of some Scandinavian species of Calamagrostis. Heredi tas 32: 131-262. Ohwi, J. 1941. Gramina Japonica 1. II. Acta Phytotax. Geobot. 10: 94-135; 261-274. - 1942. Ditto III. IV. Ibid. 11: 27-56; 145-193. Ono, H. and T. Tateoka. 1953. Karyotaxonomy in Poaceae I. Chromosomes and taxono mic relations in some Japanese grasses. Bot. Mag. Tokyo. 66: 18-27. Parthasarathy, N. 1939. Cytological studies in Oryzeae and Phalarideae. Ann. Bot. 3: 43-76. Stebbins, G. L., Jr. and R. M. Love 1941. A cytological study of California forage grasses. Amer. Jour. Bot. 28: 371-382. Uchikawa, I. 1935. Karyological studies in Japanese Bamboo II. Further studies on chromosome number. Jap. Jour. Genet. 11: 308-313.