Page 1 植物研究雜誌 J. Jpn. Bot. 77: 129 138 (2002) Cytotaxonomic
Total Page：16
File Type：pdf, Size：1020Kb
ふふ市巴一司，物bA1.E1L涜恥山判・ホ正也誌 4・ τ L3 d， J'周 ウ nxuρAUnUウ-EF B M Cytotaxonomic Cytotaxonomic Study of Ferns from China 11. Species of Fujian Su-Juan Su-Juan LIN a， Hui-Ru ZHUANG b，Kunio IWATSUKI c and Hai-Sheng Lu b aDepartment aDepartment of Biological Science ， Graduate School of Science ，University of Tokyo ， Hongo 7-3-1 ，Bunkyo-ku ，Tokyo ， 113-0033 JAPAN; bTh e Bioengineering College ，F 吋ian Teacher's University ，Fuzhou 35007 ，Fujian ，CHINA; CThe CThe University of the Air ，Wakaba 2-11 ，Mihama-ku ，Chiba ， 261-8586 JAPAN (Received on August 8，2001) A cytotaxonomic study of ferns from Fujian Province ，China ，was carried ou t. The reproductive reproductive modes of 31 species in 18 genera were examined using a conventional method ， and the chromosome numbers were counted for 24 species ，including 12 newly examined examined in China. The chromosome numbers of both Lygodium microstachyum and L. scandens scandens are 2n = 60. Pteris sem 伊innata is a sexual tetraploid with 2n = 116 chromo- somes ， while P. esquirolii has 2n = ca. 90 chromosomes and is considered to be an agamosporous agamosporous triploid. Five species were observed in Dryopteris ，all of them being agamosporous. agamosporous. Deparia japonica has been recorded from J apan as a hexaploid ， with n = 120 120 chromosomes but this study reports a sexual tetraploid with 2n = 164 chromosomes from from Fujian. Thelypteris glanduligera and T. parasitica are agamosporous triploids with 2n 2n = 108 chromosomes. (Continued from J. Jpn. Bo t. 71: 214-222 ， 1996) Key words: agamospory ，Fujian Province ，reproductive mode ，pteridophyta. In In studies of the biodiversity and Obviously ， Fujian is also one of the prov- systematics systematics of Asian pteridophytes ，cytologi- inces with a rich pteridophyte flora. Four- cal cal information from Chinese ferns is indis- hundred and four species (including 25 en- pensable. pensable. Although more than 300 Chinese demic) of ferns and fern-allies have been re- pteridophytes pteridophytes have been studied cyto- corded in F吋ian [Lin et al.， 1982 ， following logically logically by both Chinese and overseas re- Ching's system (1 978)]. Approximately 37 searchers searchers (Lin et al. 1996) ， this is only % of the total Fujianese species range to around around 10 % of the 3000 or so species found Japan ，and more than 12 % of the species to in in China. Lin et al. (1996) have previously Taiwan. As far as we know ， the F吋ianese performed performed a cytotaxonomic study of Chinese pteridophytes have never been investigated ferns ferns (Series 1) from Yunnan. As the con- cytologically ， with the exception of a few tinuance ， in the present study ，we carried out Dryopteris species (Weng 1989). cytological cytological observations on material from As a first step in the systematic studies of F吋ian. Fujianese pteridophytes ，we 問 port here the Fuiian Fuiian Province is located in the south- chromosome numbers of 24 species and re- eastern eastern coastal area of China. The variable productive modes of 31 species. The chro- landforms landforms and warm ，humid climate provide mosome numbers of some species are Fujian Fujian with various ecosystems ，which sup- counted for the first time in China. The pre- port port an abundance of plant diversity. sent study expects to contribute to our wider -129- 130 130 植物研究雑誌第77 巻第3号 平成14 年6月 knowledge knowledge of the Chinese fems ， and to make reproductive modes (Yoroi and Iwatsuki possible possible a comparative study of the 1977 ，Murakami and Iwatsuki 1982 ， Kato et pteridophyte pteridophyte floras of East China and Japan. al. 1992). The presence of 32 spores per spo- rangium rangium is supporting evidence for 島'I aterials and Methods distinguishing agamospory from the normal As shown in Table 1 ，materials were col- sexual type with 64 spores per sporangium. lected lected from the Linshi Forest center of In cases where spores escaped from the split Fuqing ， the Forest Park of Fuzhou ， and of sporangia of dry specimens ， the spore num- the the Gushan mountain in Fuzhou ，southeast of ber was estimated to be 64 based on practice Fujian. Fujian. Voucher specimens 紅 'e deposited in counts of more than 32 in each sporangium. the the Herbarium ， the Bioengineering Co l1 ege ， On the other hand ，if the practice count was Fujian Fujian Teacher 乍 University. lower than 32 ，it was considered to be 32- Fresh Fresh root tips were pretreated with 0.002 spored. M 8-hydroxyquinoline solution for 4-6 In the present study ， the chromosome hours hours at 18-20 oC ， and then fixed in 3:1 ace- numbers of 12 species were newly reported tic tic acid: alcohol (99 %) in the field ， for ob- for China. Cytotaxonomically noteworthy servation servation of somatic chromosomes. The species 訂 'e described and discussed below. observation observation method follows Lin et al. (1996). Frond Frond material was fixed in K'nop solution Lygodium About 40 species of Lygodium for for gametic observation and spore counting. are recorded worldwide (Iwatsuki 1992). Dry specimens were also used for spore Only a few species have been studied counts ， with more than 10 sporangia being cytologically ， the basic chromosome num- counted counted for each individua l. bers of the genus being variously reported as x = 28 ， 29 or 30 (Mitui 1965 ，1968 ， Kurita Results Results and Discussion 1967 ， Tsai and Shieh 1983 ，Roy and Rao The results are shown in Table 1 and Figs. 1985 ，Walker 1985 ， Singh and Roy 1988 ， 1-18. 1-18. The somatic chromosomes of 24 spe- N akato 1990 ， Ammal and Bhavanandan cies cies belonging to 14 genera of 10 families 1992 ，Takamiya 1995). were were examined and the reproductive modes There are eleven species of Lygodium in of of 31 species of 18 genera were inferred by China ， four of which are found in F吋ian ， but spore spore counting. The frond materials were no previous cytological data were available used used for spore counts as the young spores in for them. In the present study ，two species ， each each unopened sporangium can be counted L. microstachyum Desv. and L. scandens (L.) exactly. exactly. However ， fronds were too old to be Sw. ， were observed cytologically. The chro- used used for gametic chromosome counting in mosome numbers of both species were re- the the present study. Dry specimens were used corded as 2n = 60. This coincided with the for for spore counts in those species for which numbers n = 30 ，2n = 60 of L. scandens from we did not have suitable frond materia l. In Nepal (Srivastava 1985) ， but not with n = 29 most most higher leptosporangiate fems ， 64 in L. microstachyum of Taiwan (Tsai and haplospores 訂 e produced in each sporan- Shieh 1983). In Japan ， L. microstachyum is gium in sexually reproductive species ， while distributed in the south of the Ryukyus ， and 32 32 diplospores are produced in each sporan- is considered to be a variety of L. japonicum gium in agamosporous species. A few sex- (Thunb.) Sw. (n = 29 ，2n = 58). To determine ual ， 32-spored groups ， such as lindsaeoid the correct base number and the relationship fems ， are the exceptions (Lin et al. 1990). between L. microstachyum and L. japoni- Thus ， spore counts can be used for inferring cum ， further research is encouraged. June June 2002 Journal of Japanese Botany Vo l. 77 No. 3 131 Figs. Figs. 1-5. Photographs of somatic chromosomes. Scale bar = 10μm. 1. Lygodium microstachyum 2n = 60. 2. 2. Microlepia marginata 2n = ca. 164. 3. M. strigosa 2n = 84. 4. Lindsaea orbiculata 2n = 176. 5. Sphenomeris Sphenomeris chinensis 2n = ca. 190. Microlepia Microlepia Microlepia is a well-known Qiu (1 988) ， Kato et al. (1992) ， Nakato et al. genus genus in Asia. About 81 % of the 70 known (1 995) and Kato and Nakato (1 999) in these species species have been recorded from China ，five studies ， the basic numbers were considered of of these being recorded from Fujian. Only to be x = 42 or 43. four four Chinese species were studied Two species ， M. marginata and M. cytologically cytologically by Weng (1 985b) ，Weng and strigosa ， were collected for this study. 132 132 植物研究雑誌第77 巻第3号 平成 14 年6月 Figs. Figs. 6-12. Photographs of somatic chromosomes. Scale bar = 10 Il m. 6. Pteris semipinnata 20 = 116. 7. Woodwardiajaponica 20 = 68.8. Arachniodes exilis 20 = 82. 9. Dryopteris gushanica 2n = 123. 10. D. varia varia 2n = 123. 11. Thelypteris glanduligera 20 = 108. 12. T. acuminata 2n = 72. June June 2002 Journal of Japanese Botany Vo l. 77 No. 3 133 Cytologically ， triploids ， te 位aploids and a good explanation for the ex 住eme diversity hexaploids hexaploids have been reported in M. seen in this genus. marginata marginata from China ，Taiwan and Japan Pteris esquirolii was cytologically ob- (Mitui (Mitui 1968 ， Nakato and Serizawa 1981 ， served here for the first time in China. Based Tsai Tsai and Shieh 1983 ，Weng 1985b ，Weng on the chromosome number 2n = ca. 90 ， and and and Qiu 1988 ， Nakato et al. 1995). For about thirty-two spores in each sporangium ， Chinese Chinese materials ， the chromosomes were it is suggested to be an agamosporous counted counted as n = 86 by Weng (1985b) and triploid in Fujian. Weng and Qiu (1 988) from Zhejiang Province Province and 2n = 168 by N akato et al. Woodwardia japonica Except for a single (1 995) from Jiangsu Province. Microlepia report (n = 17) from Zhejiang (Weng and marginata marginata is a morphologically variable and Qiu 1988) ，Woodwardiajaponica has always very very common species in F吋ian. Our chro- reported as a sexual ，diploid species with n = mosome and spore counts showed 2n = ca. 34 ，2n = 68 chromosomes in China and 164 ， and about 58 (64) spores in each spo- Japan (Mitui 1965 ，1968 ，Takamiya et al.