Cytologia 41: 5-22, 1976

Cytological Observations on some W. Himalayan Monocots ll. Smilacaceae, and Trilliaceae

P. N. Mehra and S. K. Sachdeva

Department of Botany, Panjab University, Chandigarh, India

Received May 16, 1974

Hutchinson (1959) segregated most of the woody non-xerophytic members from the former family Liliaceae and placed them into several distinct families like Smila caceae, Ruscaceae and Philesiaceae and also raised the tribe Parideae of Krause (1930) to the family level designated as Trilliaceae. The family Liliaceae (sensu Hutchinson) now consists of 250 genera and 3,700 , while the family Smilaca ceae includes 4 genera and 375 species (Willis 1966). The family Trilliaceae is the smallest of the three being comprised of 4 genera and 53 species (Willis l.c.). A perusal of the literature reveals that cytological data on Smilacaceae are rather meagre, but the families Liliaceae and Trilliaceae have been fairly well studied as they provide ideal material for such investigations. Although a number of reports on the cytology of Indian members have appeared, several W. Himalayan taxa are still unexplored. In order to fill this gap the present study was undertaken. This communication presents cytological data on 17 taxa of this region.

Materials and methods

The materials were collected from nature in the W. Himalayas. Voucher specimens have been deposited in the Herbarium of the Department of Botany,

Panjab University, Chandigarh. For meiotic studies buds were fixed in

1:3 acetic alcohol with an addition of a little chloroform for a period of about 24 hours and then transferred to 95% alcohol. Squashes were made in 2% aceto carmine. For mitotic studies young root-tips were pretreated with 0.003M solution of 8-hydroxyquinoline for 3-4hours. The root-tips were rinsed in water, fixed in

1:3 acetic alcohol and macerated in 9:2 mixture of 2% lacmoid solution in 45 acetic acid and N.HCI. Squashes were made in 2% aceto-lacmoid solution. Graph paper ruled in 1mm squares was used for drawing idiograms. The primary con striction was represented by 2mm gap and the secondary constriction by 1mm gap.

In determining the chromosome morphology Battaglia's (1955) terminology was employed. The terms median, submedian, subterminal and terminal chromo somes have been used for describing their morphology. Unless otherwise stated, the photomicrographs were made at a uniform magnification of •~1500. Ex planatory diagrams have been given wherever found necessary. Photomicrographs have been taken on Printon R Agfa films. The prints were made using different grades of Agfa glossy paper. 6 P. N. Mehra and S. K. Sachdeva Cytologia 41

Results

Table 1 lists the species, their chromosome numbers and the specific localities from where they were collected. The details are as follows:

Table 1. 1976 Cytological Observations on some W. Himalayan Monocots II 7

Table I (cont'd)

* Species investigated for the first time . t New chromosome number report (New Cytotypes) . Literature cited in Table 1 according to Darlington and Wylie (1955), Cave et al. (1956-1968), Love and Love (1961), Fedorov (1969) and Taxon (1969-1973).

Smilacaceae L. Seven species of the genus are met with in the W. Himalayas (Hooker 1894). Three species have presently been worked out. S. aspera L. is well represented in the Simla hills between 1,500-2,100m. Its roots are valued as substitute for Indian sarsaparilla. PMCs revealed the haploid chromosome number to be n=16 (Fig. 1). Meiosis was normal. The present count conforms to the report of Carvalho (1948). S. elegans Wall. occurs in the Kumaon hills at an altitude of 1,800-2,100m. Its chromosome number, as determined from PMCs, was found to be n=16 (Fig. 2). The course of meiosis was perfectly normal. The species has been studied for the first time. S. parvifolia Wall. is common in the Simla and Kumaon hills at 1,500-2,100m. PMCs revealed 16 bivalents at M-I (Fig. 3). Meiosis was regular. This is the first report for the species. A study of the literature reveals that only fragmentary reports on some of the species of the genus exist. Mention may be made of the work of Lindsay (1930), Nakajima (1933, 1937), Jensen (1937), Lewis et al. (1962) and Larsen (1966). The genus is polybasic with x=13, 14, 15 and 16 (Darlington and Wylie 1955). All the species investigated to date are diploids with the sole exception of S. china which is a tetraploid with 2n=60 (Sato 1942). Liliaceae 8 P. N. Mehra and S. K. Sachdeva Cytologia 41

Asparagus L. Five species occur in the W. Himalayas of which three have been presently studied. A. curillus Ham. is met with in the Kumaon hills at 900-1,500m. Ten bivalents were discernible at M-I (Fig. 4). Meiosis was normal. The present finding con

Figs. 1-6. 1, , n=16 at early M-I . 2, S. elegans, n=16 at early M-I (arrows in dicate univalents). 3, S. parvifolia , n=16 at M-I. 4, Asparagus curillus, n=10 at M-I f . 5, A. ilicinus, n=10 at M-I. 6, Smilacina purpurea , 2n=36 in root-tip mitosis. All •~1500 . 1976 Cytological Observations on some W. Himalayan Monocots II 9 firms the report of Malik and Tandon (1959). A. filicinus Ham. was collected from the Kashmir hills at 1,500-2,100m. At M-I ten bivalents were observed (Fig. 5). Meiosis was found to be regular. The present report is in conformity with the findings of Larsen (1963). A. racemosus Willd. occurs commonly in the Nainital and Kashmir hills at an altitude of 900-1,500m. Meiotic chromosome number in the species was found to be n=10 (Fig. 7). The course of meiosis was normal. This report is in agree

Figs. 6a-9. 6a, explanatory diagram to Fig. 6. 7, Asparagus racemosus, n=10 at M-I. •~2500.

8-9. Eremurus himalaicus. 8, A-1 showing seven chromosomes at each pole. 9, pollen mitosis showing n=7. Both •~1500. ment with the findings of Sharma and Bhattacharyya (1957). Thombre (1959) and Raju (1960), however, observed 2n=30 and 2n=40 respectively, obviously indicat ing the existence of cytological races in this species. Smilacina Desf. Only one species of this genus, S. purpurea occurs in the W. Himalayas. 10 P. N. Mehra and S. K. Sachdeva Cytologia 41

S. purpurea Wall, occurs commonly in the Simla and Kumaon hills between

2,700-3,300m. Root-tip mitoses gave a mitotic count of 2n=36 chromosomes

(Figs. 6, 6a). The karyotype consisted of ten pairs of large and eight pairs of small chromosomes (Fig. 19). Of the large chromosomes, two pairs possessed median

primary constriction, three pairs submedian and five pairs subterminal primary constriction. One chromosome pair had two secondary constrictions, one situated

subterminally and the other submedianly in the long arm. Of the eight pairs of

small chromosomes, three were median, three submedian and two subterminal.

Chromosome size ranged from 10ƒÊ to 3ƒÊ.

Mehra and Pathania (1960) earlier reported n=18 in this species. The base

number for the genus is x=9 (Darlington and Wylie 1955) and the species, therefore,

is at tetraploid level. Majority of the species of this genus investigated to date are

also tetraploids. However, Kwano (1966) observed tetraploid, octaploid and 16

ploid races in a single species S. racemosa. Photomicrographs of S. japonica var. robusta and S. yezoensis given by Hara and Kurosawa (1963) and that of S. formo

sana by Chuang et al. (1963) showed the basic karyotypes to consist of ten pairs of

large and eight pairs of small chromosomes, thus agreeing exactly with the Himala

yan species.

Eremurus Bieb.

E. himalaicus Baker is widespread on dry rocks of Kashmir hills at 2,100

3,000m. It is a highly ornamental horticultural with white . The chromosome number was determined from PMCs and pollen mitoses . PMCs revealed n=7. At A-I 7:7 distribution of chromosomes was observed (Fig. 8).

Meiosis was normal. Pollen mitoses too showed n=7 (Fig. 9) . The karyotype consisted of five large and two small chromosomes (Fig . 20). All the five large chromosomes possessed subterminal primary constriction . Of the two small chromosomes, one possessed median and the other submedian centromere. None of the chromosomes showed secondary constriction . Chromosome size ranged from 9ƒÊ to 4ƒÊ.

The present report is in agreement with the findings of Burstrom (1929) and

Oksala and Therman (1958). Sato (1942) described the karyotype of E . robustus (2n=14) in which he observed five pairs of large chromosomes with subterminal primary constriction and two pairs of short chromosomes also with subterminal primary constriction, thus suggesting a highly advanced type of karyotype in the species. The presently worked out species is diploid , x=7 being the base number for the genus. Polyploidy does not seem to have played any role in the evolution of species within the genus, as all the species hitherto investigated are diploids .

Lilium L. Six species of this genus occur in the W . Himalayas (Hooker 1894). Two species have presently been worked out . L. cordifolium Thunb. occurs in the interior ranges of the Kumaon hills between

1,800-3,000m. The chromosome number was determined only from root -tip mitoses which showed 2n=24 (Fig. 10) . The karyotype is asymmetrical with a very gradual transition from long to short chromosomes except for two chromo somes (Fig. 21). The two largest pairs had submedian primary constriction and one of these possessed a secondary constriction in the short arm . All the remaining 1976 Cytological Observations on some W. Himalayan Monocots II 11

ten pairs were with subterminal primary constriction and of these, two pairs had a subterminal secondary constriction in the long arm. Chromosome size ranged from 17ƒÊ to 8ƒÊ. The present report is in conformity with that of Sato (1932),

Hall (1934) and Stewart (1947).

L. polyphyllum Don. is widespread in Simla, Kumaon and Kashmir hills be tween 2,100-3,300m. The species is of considerable horticultural importance.

Root-tip mitoses revealed 2n=24 (Figs. 11, lla). The karyotype consisted of two pairs of long and ten pairs of relatively shorter chromosomes (Fig. 22). Both the large pairs had submedian primary constriction. All the ten pairs of relatively shorter chromosomes possessed subterminal primary constriction and, of these, two pairs had a secondary constriction situated submedianly in the long arm and one chromosome of another pair showed a secondary constriction in the short arm.

Chromosome size ranged from 20ƒÊ to 11ƒÊ. The species has been investigated for the first time.

Stewart (1947) worked out the karyotypes of 48 species and varieties of this

genus. He observed some species possessed three different karyotypes, while as

Figs. 10 and 11a. 10, Lilium cordifolium, 2n=24 in root-tip mitosis. •~1150. l1a, explanatory diagram to Fig. 11.

many as four species had identical karyotypes. The number, position and activity of the secondary constriction was also found to be variable. B-chromosomes too were observed in a number of species (Stewart 1943, 1947). Polyploidy is very rare in the genus and is reported in nature only in L. tigrinum (Darlington and Janaki-Ammal 1945). Mehra and Kachroo (1951) who studied chromosome morphology in some Lilium species also arrived at the same conclusion. Apart from polyploids, the occurrence of aneuploids has also been reported (Stewart 1943). Fritillaria L. Five species of this genus are met with in the W. Himalayas. Only one species has been worked out. F. roylei Hook. is well represented in Kashmir hills at an altitude of 2,850 3,900m. The plant is of great medicinal value. The somatic chromosome number for the species was found to be 2n=24 (Figs. 12, 12a). One of the twelve pairs possessed median primary constriction, another submedian and the remaining ten pairs had subterminal primary constriction (Fig. 23). One subterminal pair showed 12 P. N. Mehra and S. K. Sachdeva Cytologia 41

s econdary constriction in the long arm. The chromosome size ranged from 16ƒÊ to 8ƒÊ. Meiosis was perfectly normal showing twelve bivalents at M-I (Figs. 13,

13a). Ten PMCs were examined and total number of chiasmata were counted.

From this value, mean chiasma frequency per cell and per bivalent was calculated

Figs. 11-12a. 11, Lilium polyphyllum, 2n=24 in root-tip mitosis. 12, Fritillaria roylei , 2n=24 in root-tip mitosis. Both •~1100. 12a, explanatory diagram to Fig. 12.

Fio. 13a. Explanatorydiagram to Fig. 13showing total and terminalchiasmata for eachbivalent . to be 43.1 and 3.60 respectively. In Figure 13a total and terminal chiasmata are given for each bivalent. Sharma and Sharma (1961) also reported 2n=24 in this species, but the karyo type of the present taxon does not tally with their description. The present authors 1976 CytologicalObservations on someW. HimalayanMonocots II 13 observed one pair of median, another pair of submedian and ten pairs of subterminal chromosomes with one subterminal pair possessing a secondary constriction, while Sharma and Sharma (l.c.) recorded one pair of median, seven pairs of submedian and four pairs of subterminal chromosomes with four pairs possessing secondary

Figs. 13-15. 13, Fritillaria roylei, n=12 at early M-1. 14, Gagea persica, n=24 at M-I. Both

•~1200. 14a, explanatory diagram to Fig. 14. 15, Gagea lutea, n=48 at one pole at A-I. •~1200. constrictions. Darlington (1936) has studied various diploid and triploid species of Fritillaria. The karyotype of the present taxon resembles very much with that of F. askabadensis. In both there are twelve pairs of somatic chromosomes of which one pair is median, another submedian and the rest are subterminal. Darlington (l.c.) also calculated mean chiasma frequency per bivalent in many diploid and 14 P. N. Mehra and S. K. Sachdeva Cytologia 41

triploid species. Among the diploid ones the mean chiasma frequency per bivalent varied from 1.8-3.0. It is obvious that the mean chiasma frequency per bivalent in the case of F. roylei is the highest among the diploid species so far investigated, being of the order of 3.6 per bivalent.

Figs. 16-18. 16, Gloriosa superba, n=11 at A-1 . 17-18. Kniphofia uvaria; 17, root-tip mitosis showing 2n=12; 18, M-1 showing 6 bivalents . All•~1500.

Gagea Salisb. Three species of this genus have been reported from the W . Himalayas. Presently only two species have been studied . G. persica Boiss. is widespread in the Kashmir hills at elevations between

1,500-2,700m. At M-I twenty four bivalents were discernible (Figs . 14, 14a). 1976 Cytological Observations on some W. Himalayan Monocots II 15

Meiosis was regular. This is the first report for the species. G. lutes Schultz. is distributed in the Simla, Kumaon and Kashmir hills be tween 2,400-3,600m in meadows. PMCs revealed a gametic number of n=48

Figs. 19-24. Idiograms. 19, Smilacina purpurea, 2n=36. 20, Eremurus himalaicus, n=7. 21, Lilium cordifolium, 2n=24. 22, L. polyphyllum, 2n=24. 23, Fritillaria roylei, 2n= 24. 24, Kniphofia uvaria, 2n =12. 16 P. N. Mehra and S. K. Sachdeva Cytologia 41

Figs. 25-26. 25, Trillium govanianum, 2n=20 in root-tip mitosis. •~1500. 26, Paris polyphylla,

2n=20 in root-tip mitosis. •~1250. 1976 Cytological Observations on some W. Himalayan Monocots II 17

(Fig. 15). In a few mother cells laggards were observed at A-I. Pollen fertility was found to be 87%. This is a new cytotype, since Westergaard (1936) reported 2n=72 in this species.

Figs. 25a-26a. 25a, explanatory diagram to Fig. 25. 26a, explanatory diagram to Fig. 26.

The base number for the genus Gagea is x=12 (Darlington and Wylie 1955). Quite high 2n numbers were observed in G. fistulosa (c. 80) and G. spathaceae (c. 102) by Bianchi (1946), and Westergaard (1936) indicating that polyploidy has played an important role in the evolution of species within the genus. 18 P. N. Mehraand S. K. Sachdeva Cytologia41

Gloriosa L. Only one species, G. superba occurs in India throughout the tropical parts. It is also cultivated for its showy flowers. PMCs revealed n=11. At A-I 11:11 distribution of chromosomes was observed (Fig. 16). Meiosis was regular. The

Figs. 27-28. Idiograms. 27, Trillium govanianum, 2n=20. 28, Paris polyphylla, 2n=20. present report is in conformity with the findings of Tjio (1948), Sharma and Sharma (1961) and Khoshoo (1956). Sharma and Sharma (l.c.) have also reported a race with 2n=90 in the species, whereas Khoshoo (1956) has reported tetraploid and hexaploid cytotypes with 2n=44 and 66 respectively. Kniphofia Moench 1976 Cytological Observations on some W. Himalayan Monocots II 19

K. uvaria L. is cultivated in the Kumaon and, Kashmir hills for its attractive

showy flowers and also occurs as an escape. Root-tip mitoses revealed 2n=12

(Fig. 17). The karyotype consisted of two pairs of large chromosomes with sub median primary constriction, while the remaining four pairs had subterminal

primary constriction (Fig. 24). In none of the chromosomes secondary constriction could be seen. Chromosome size ranged from 10ƒÊ to 6ƒÊ. The present description

of the karyotype agrees with that of Webber (1932) differing only in respect of the

presence of secondary constriction. Webber found a secondary constriction in one of the subterminal chromosome pairs while no such thing was observed in the

present material. However, de Wet (1960) observed three pairs of submedian chromosomes each with a secondary constriction in the long arm, one pair of median

and two pairs of submedian chromosomes in this species. PMCs revealed n=6

(Fig. 18). Meiosis was normal. The base number for the genus is x=6 (Darlington and Wylie 1955). The presently worked out species is, thus, at diploid level. Mof

fett (1932 in Sato, 1942) observed diploid, tetraploid and octaploid forms in K.

nelsonii.

Trilliaceae Trillium L. Two species of this genus occur in India.T

. govanianum Wall. is distributed in the Kashmir hills at 2,700-3,000m.

The chromosome number as determined from root-tip mitoses was 2n=20 (Figs.

25, 25a). Only a single cell with clear chromosomes was analysed for karyotypic

study. Several chromosome pairs were found to be heteromorphic (Fig. 27).

The largest chromosome pair possessed median to submedian primary constriction. The pair next in length possessed median primary constriction. Of the remaining

eight pairs, four had submedian and the rest four had subterminal primary con

striction. One of the two chromosomes of the pair with median primary constric

tion (3-4) possessed two secondary constrictions, one in each arm. Of the two

chromosomes comprising a subterminal pair (5-6), one possessed an attenuated

satellite attached to the distal end of short arm, while the second chromosome of

this pair had three secondary constrictions, one in the long arm and two in the short

arm. Of the two chromosomes constituting another subterminal pair (9-10), one

showed two secondary constrictions while the other had only a single secondary

constriction in the long arm. One chromosome of a submedian pair (19-20) pos

sessed a secondary constriction situated near the centromere in the short arm. The

chromosome size ranged from 27ƒÊ to 12ƒÊ.

The present chromosome report agrees with the finding of Hara (1966) but the

karyotypes of the two taxa show marked differences especially in regard to the

number and position of secondary constrictions. The karyotype of the present

taxon (analysed from a single clear cell of the root-tip) revealed several pairs to be

heteromorphic, while in Hara's figures the pairs are all homomorphic. In the present taxon there were one pair of median-submedian chromosomes, another pair of median chromosomes, four pairs of submedian chromosomes and four pairs of subterminal chromosomes with varying number of secondary constrictions in the chromosomes constituting one median, one submedian and two subterminal pairs. On the other hand the drawings of Hara (l. c.) show that there were two 20 P. N. Mehra and S. K. Sachdeva Cytologia 41

pairs of median, four pairs of submedian and four pairs of subterminal chromo somes with one secondary constriction in two subterminal pairs only. Malik (1961)

has reported haploid chromosome number in this species as n=10.

Paris L. The genus is represented in the W. Himalayas by only a single species.

P. polyphylla Smith. is widespread in the Kumaon hills at elevations between

1,800-3,000m. The root-tip mitoses showed 2n=20 (Figs. 26, 26a). Here too

the karyotype was studied from a single cell which exhibited well spread out chromo

somes. Two chromosome pairs possessed median primary constriction, four pairs

submedian and another four had subterminal primary constriction. One chromo

some pair with submedian primary constriction (11, 12) revealed a secondary con

striction situated subterminally in the short arm cutting of a small satellite. The

individual chromosomes of most of the pairs constituting the complement varied

greatly in length as seen in the idiogram (Fig. 28). The largest chromosome in the complement measured about 60 p while the smallest about 20ƒÊ. Kurosawa's

(1966) drawing of chromosomes of this species also revealed this type of karyotype except for the difference that while Kurosawa's drawing show the chromosomes to

match perfectly into pairs, in the present taxon individual chromosomes constitut ing the various pairs varied greatly in their length. The present species is at tetra

ploid level, x=5 being the base number for the genus. The other taxa of this species are reported to be diploids ccasionally with 1-2 B chromosomes (Gotoh and

Kikkawa 1937, Darlington 1941, Larsen 1963).

Discussion

There is nothing very much further to discuss after what has been appended in the text in respect of each genus and species. However, one remarkable fact needs to be emphasised. In both Trillium and Paris-genera possessing exceptionally long chromosomes, homologous chromosome pairs were not noticed. Either all, or at least some of the pairs were heteromorphic indicating wide spread transloca tions in the species in their root-tips. In order to assess the significance of these in the evolution of various taxa, it is imperative to study extensively the karyotypes from as many cells as possible in the root tips of the same individual and also from the individuals belonging to different populations. Already it has been brought to light that in such with extensive vegetative multiplication through bulbs, corms and rhizomes, different populations of species from different geo graphical areas show variations in karyotypic configurations (cf. Stewart 1947, Mehra and Pathania 1960). Of course, such studies have to be further supplemented with investigations of the nature of karyotypes in the sex cells, pairing phenomenon at meiosis, as also the extent of fertility of the pollen grains as well as the seeds to be of real value in drawing pertinent conclusions . It is also pertinent to point out that Sharma (1956) attaches considerable im portance to the evolution of new taxa on the assumption that such cells, were they to enter the constitution of individuals as a result of vegetative reproduction , would give rise to new forms. This could very well be the case but cogent and unequivocal proof in this regard has yet to come. 1976 Cytological Observations on some W. Himalayan Monocots II 21

Summary Cytological observations on 17 W. Himalayan taxa belonging to Smilacaceae, Liliaceae and Trilliaceae are presented. Four species have been investigated for the first time. These are Smilax elegans (n=16), S. parvifolia (n=16), Lilium polyphyllum (2n=24) and Gagea persica (n=24). New chromosome number has been recorded in Gagea lutea (n=48). Detailed karyotype analysis has been made in Smilacina purpurea (2n=36), Eremurus himalaicus (n=7), Lilium cordifolium (2n=24), L. polyphyllum (2n=24), Fritillaria roylei (2n=24), Kniphofia uvaria (2n=12), Trillium govanianum(2n=20) and Paris polyphylla (2n=20).

Acknowledgements

Financial assistance from U. S. Department of Agriculture under a PL 480 Project (Grant No. FG-In-281) to the senior author is gratefully acknowledged. We are thankful to Head of the Division of Botany, F. R. I., Dehradun for the help in identification of . Our thanks are also due to Atomic Energy Commission for providing the laboratory facilities at the High Altitude Research Laboratory, Gulmarg, Kashmir.

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