Cytomorphological Diversity in Some Members of Family Asteraceae from the Ecologically Disturbed Habitats of Solang Valley, Kullu District, Himachal Pradesh

Maninder Kaur* and Vijay Kumar Singhal

Department of Botany, Punjabi University, Patiala-147002, Punjab, India

Received September 30, 2014; accepted January 5, 2015

Summary Present cytomorphological surveys include meiotic studies and chromosome counts in 42 species under 93 accessions collected from the various localities of Solang Valley in Kullu district, Himachal Pradesh at different altitudes ranging from 2,400 to 3,100 m. Artemisia salsaloides (n=10), Dandranthema boreale (n=36), Ligularia fischeri (n=30) and Tussilago farfara (n=12) are recorded as the first ever chromosomal counts from India. Additional/variable cytotypes are recorded in Anaphalis nepalensis (2n=6x=42), A. triplinervis (2n=6x=42), Artemisia nilagirica (2n=4x=36; 2n=6x=54), Artemisia salsoloides (n=10), Brachyactis pubescens (2n=4x=36), Dandranthema boreale (2n=8x=72), Taraxacum officinale (2n=8x=64) and Tussilago farfara (2n=2x=24). Intraspecific polyploid cytotypes are reported in Anaphalis nepalensis (4x, 6x), Artemisia nilagirica (4x, 6x) and Taraxacum officinale (2x, 3x, 4x, 5x, 6x) from the valley. Existence of B-chromosome has been reported in Cnicus wallichii (2n=34+0-1B) which is the first ever record for the species at world level.

Key words Chromosome count, Male meiosis, Intraspecific cytotype, Asteraceae, Meiotic abnormality.

Kullu district, situated in the central part of Himachal Pradesh with an altitudinal range of 1,100–4,300 m, is represented by three valleys̶Kullu Valley, Parvati Valley and Solang Valley (Map 1a, b). Solang Valley, named after Solang River, lies between 77°2′29″–77°12′2″E longitude and 32°18′25″–32°24′57″N latitude. The valley originates from Beas Kund Glacier, culminates into Beas River near Palchan and covers an area of 11,215.03 ha. The valley, which is situated at the border of Greater Himalaya and Trans-Himalaya, harbors a rich biodiversity of plants. Based on its tourism potential, the area is being developed to attract tourists and, in doing so, several construction activities are going on in the valley. Also, the area is being intruded by more and more number of people resulting in serious threat to its bio-resources. Besides, the valley which was once ecologically undisturbed, has now become fragile and there is every possibility of erosion of many of its bio-resources in the near future. Keeping in view the ongoing threats to the existing plant diversity, the studies have been undertaken by the authors to explore the cytomorphological diversity in the ﬂowering plants of Solang Valley. Some of the findings in the form of an asynaptic mutant in the tetraploid cytotype (2n=4x=48) of Solanum nigrum L. (Singhal et al. 2012), reciprocal translocations in Achillea millefolium L. (Singhal et al. 2014) and cytomixis in Nepeta govaniana (Wall. ex Benth.) Benth. (Kaur and Singhal 2014) have already been published. The present communication includes the chromosomal counts, male meiotic studies and pollen fertility analysis in the members of family Asteraceae.

* Corresponding author, e-mail: [email protected] DOI: 10.1508/cytologia.80.203 204 M. Kaur and V. K. Singhal Cytologia 80(2)

Map 1. (a–c) a. Location of Himachal Pradesh in India. b. Location of Kullu district and Solang Valley in Himachal Pradesh. c. A broader view of Solang Valley.

The family Asteraceae contains 1,600–1,700 genera and approximately 23,600 species distributed all around the globe except Antarctica (Funk et al. 2009). This group furnishes more than 10% of the total ﬂowering plants and is cosmopolitan in distribution (Mabberley 1997). In India, the family contains 900 species under 167 genera (Hajra et al. 1995). Several species possess medicinal properties and many are known as ornamentals. Insecticides, oils, dyes and edible products are obtained from some members. The members are characterized by ﬂorets arranged on a receptacle in centripetally developing heads surrounded by bracts, anthers fused in a ring, with pollen pushed or brushed out by the style, and by the presence of achenes (cypselas) usually with a pappus (Funk et al. 2009). Extensive cytological information has been made available on the members of Asteraceae owing to the major cytological surveys conducted by Stebbins et al. (1953), Raven et al. (1960), Moore and Frankton (1962), Ornduff et al. (1963), Turner and Irwin (1960), Turner et al. (1961, 1962, 1967), Turner and King (1964), Turner and Lewis (1965), Solbrig et al. (1969), Strother (1976), Stuessy (1977), Turner and Powel (1977), Heywood et al. (1977), Razaq et al. (1988), Keil et al. (1988), Watanabe et al. (1995, 1997, 1999), Xiong et al. (1995), Carr et al. (1999), Valles et al. (2008) and Garcia et al. (2013). Cytologically, the members have also been studied by various workers from India̶Khoshoo and Sobti (1958), Sobti and Singh (1961), Koul (1964a, b), Mehra et al. (1965), Sharma and Sarkar (1967–1968), Subramanyam and Kamble (1967), Singh (1972), Mehra and Remanandan (1969, 1974, 1975, 1976), Shukur et al. (1977), Mathew and Mathew (1978, 1983, 1987, 1988), Gupta and Gill (1979, 1980, 1983, 1984a, b, 1989), Nirmala and Rao (1984), Kaul and Bakshi (1984), Gupta et al. (1989, 2010, 2013), Rajalakshmi and Jose (2011), Bala and Gupta (2013) and Usha et al. (2013). However, no such studies have ever been undertaken on the members of Asteraceae from this geographically isolated and ecologically disturbed area.

Materials and methods

The materials for cytological studies were collected from the wild plants growing at various altitudinal ranges of Solang Valley, Kullu district of Himachal Pradesh, India, during the months of April–September, 2010–2013 from the different localities (Map 1c). Cytologically investigated species were identified by consulting ﬂoras of different regions, such as the Flora of Himachal Pradesh (Chaudhary and Wadhwa 1984), Flora of Lahaul-Spiti (Aswal and Mehrotra 1994) and 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 205

Flora of Kullu district (Dhaliwal and Sharma 1999). The plant specimens were also compared to the samples lying in the Herbaria, Department of Botany, Punjabi University, Patiala (PUN), Botanical Survey of India, Dehra Dun (BSI), and Forest Research Institute, Dehra Dun (FRI). Voucher specimens of the cytologically worked out accessions were deposited in the Herbarium, Department of Botany, Punjabi University, Patiala. For male meiotic studies, capitula of suitable sizes randomly collected from five individuals in each population, were fixed in Carnoy’s fixative (mixture of ethanol, chloroform and glacial acetic acid in a volume ratio of 6 : 3 : 1) for 24 h, transferred to 70% alcohol and stored in a refrigerator until analysis. Pollen mother cells (PMCs) were prepared by squash technique and stained with 1% acetocarmine. Freshly prepared slides were carefully examined to determine the chromosome number. PMCs were also analysed for detailed meiotic behaviour at different meiotic stages, diakinesis, metaphase I (MI), anaphases-I/II (AI/II), telophases-I/II (TI/II) and sporad stage. In accessions with a normal meiotic course, a total of 10–30 PMCs were examined for determining the chromosome counts, while in cytologically abnormal accessions, 30–50 slides prepared from different anthers/ﬂorets were analyzed. Pollen fertility was estimated through stainability tests by squashing the anthers from mature capitula in glyceroacetocarmine (1 : 1) mixture, and 1% aniline blue dye. Well-filled pollen grains with stained nuclei were taken as apparently fertile while shriveled and unstained ones were counted as sterile. Chromosome spreads were analyzed with an Olympus light microscope, and the best plates of chromosome counts, meiotic abnormalities, sporads and pollen grains (fertile, sterile) were photographed from the temporary mounts with a Nikon Eclipse 80i microscope. The previous chromosome counts in the worked out species were compiled from chromosome indexes, viz. Darlington and Wylie (1955), Ornduff (1968, 1969), Bolkovskikh et al. (1969), Moore (1970, 1971, 1972, 1973, 1974, 1977), Fedorov (1969), Löve and Löve (1980, 1982, 1986), Goldblatt (1981, 1984, 1985, 1988), Goldblatt and Johnson (1990, 1991, 1994, 1996, 1998, 2000, 2003, 2006), Kumar and Subramaniam (1986) and Khatoon and Ali (1993). Besides, IAPT/IOPB Chromosome Reports and various journals and the website of IPCN (http://www.tropicos.org/ Project/IPCN) were also consulted.

Results and discussion

Present cytomorphological surveys include the exact chromosome counts, detailed meiotic course and pollen fertility in 103 wild accessions falling under 8 tribes, 28 genera and 42 species of family Asteraceae collected from the geographically isolated and severely disturbed habitats of Solang Valley. The data regarding specific locality with altitude along with GPS coordinates, voucher specimen number (PUN), meiotic chromosome number, ploidy level, pollen fertility (%age) and previous chromosome counts are given in Table 1. Four species, Artemisia salsaloides (n=10), Dandranthema boreale (n=36), Ligularia fischeri (n=30) and Tussilago farfara (n=12) present the first ever chromosomal records from India. Additional/variable cytotypes are recorded in Anaphalis nepalensis (2n=6x=42), A. triplinervis (2n=6x=42), Artemisia nilagirica (2n=4x=36; 2n=6x=54), Artemisia salsaloides (n=10), Brachyactis pubescens (2n=4x=36), Dandranthema boreale (2n=8x=72), Taraxacum officinale (2n=8x=64) and Tussilago farfara (2n=2x=24). Intraspecific cytotypes at various ploidy levels are reported from the valley in Anaphalis nepalensis (4x, 6x), Artemisia nilagirica (4x, 6x) and Taraxacum officinale (2x, 3x, 4x, 5x, 6x). Presence of B-chromosome comes into light in Cnicus wallichii (2n=34+0-1B), which is the first ever report for the species at world level. Detailed results covering meiotic chromosome pairing and segregation, microsporogenesis and pollen fertility have been given in the species of cytological interest. 206 M. Kaur and V. K. Singhal Cytologia 80(2)

Table 1. Information on locality with altitude and GPS coordinates, accession number/s (PUN), meiotic chromosome number, ploidy level, pollen fertility %age and previous chromosome count of the cytologically investigated species.

Localities of collections Accession Meiotic Pollen Ploidy Previous counts Taxon (Altitude in meters) number/s chromosome fertility level if any** with GPS coordinates (PUN)* number (‘n’) %age

1. Achillea millefolium L. Palchan, 32°18′47″N 58571 9 2x 68 2n=18, 27, 34, 36, 77°9′48″E/2400 36+0-2B, 45, 48, Solang Nullah, 58570 9 2x 100 53, 54, 54+B, 32°18′13″N 54+0-3B, 60-66, 77°7′31″E/ 2700 63, 72, 74, 81±5 56885 9 2x 100 Dhundhi, 32°18′37″N 58572 9 2x 71 77°8′59″E/ 3050 2. Ageratum conyzoides Palchan, 32°18′47″N 57897 10 2x 100 2n=20, 36, 40 Linn. 77°9′48″E/2400 57898 10 2x 100 57900 10 2x 98 57901 10 2x 96 3. Anaphalis adnata Wall. Palchan, 32°18′47″N 59015 14 4x 100 2n=14, 28 ex DC. 77°9′48″E/2400 Schnag, 32°14′22″N 59047 14 4x 100 77°11′19″E/2450 4. A. nepalensis (Spreng) Palchan, 32°18′47″N 59016 14 4x 100 2n=28, 56 Hand.–Mazz. 77°9′48″E/2400 (=A. nubigena DC.) Schnag, 32°14′22″N 59029 21 6x 87 77°11′19″E/2450 Schnag, 32°14′22″N 59031 21 6x 98 77°11′19″E/2450 Dhundhi, 32°18′37″N 59043 21 6x 94 77°8′59″E/3050 5. A. royleana DC. Palchan, 32°18′47″N 59017 14 4x 100 2n=28 77°9′48″E/2400 Dhundhi, 32°18′37″N 59049 14 4x 100 77°8′59″E/3050 6. A. triplinervis (Sims.) Palchan, 32°18′47″N 59028 21 6x 100 2n=28 Clarke 77°9′48″E/2400 Schnag, 32°14′22″N 59053 21 6x 99 77°11′19″E/2450 Dhundhi, 32°18′37″N 59054 21 6x 99 77°8′59″E/3050 7. Artemisia nilagirica Palchan, 32°18′47″N 58969 18 4x 100 2n=18, 18+0-4B (Clarke) Pamp. 77°9′48″E/2400 Bahang, 32°16′25″N 58970 18 4x 99 77°10′51″E/2450 Palchan, 32°18′47″N 58973 27 6x 97 77°9′48″E/2400 Vashisht Village, 58971 27 6x 93 32°15′32″N 77°11′24″E/2475 Solang Village, 58972 27 6x 94 32°18′47″N 77°9′48″E/2750 8. A. salsoloides Willd. Palchan, 32°18′47″N 58974 10 2x 100 2n=18 77°9′48″E/2400 9. A. scoparia Waldst. & Palchan, 32°18′47″N 58975 9 2x 96 2n=18, 36 Kit. 77°9′48″E/2400 Bahang, 32°16′25”N 58976 9 2x 98 77°10′51″E/2450 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 207

Table 1. Continued.

Localities of collections Accession Meiotic Pollen Ploidy Previous counts Taxon (Altitude in meters) number/s chromosome fertility level if any** with GPS coordinates (PUN)* number (‘n’) %age

10. Aster thomsonii CB. Palchan, 32°18′47″N 58978 9 2x 100 2n=18, 18+0-4B Clarke 77°9′48″E/2400 Palchan, 32°18′47″N 58979 9 2x 99 77°9′48″E/2400 BRO Office, 58980 9 2x 100 32°19′22″N 77°9′23″E/2400 11. Bidens biternata (Lour.) Burua, 32°19′22″N 59010 36 6x 100 2n=24, 72 Merr. & Sherff. 77°9′23″E/ 2450 (=Coreopsis biternata Lour.) 12. B. pilosa Linn. Dhundhi, 32°18′37″N 59011 36 6x 100 2n=24, 36, 40, 46, 77°8′59″E/3050 48, 70, 72, 76, 96 13. B. tripartita Linn. Dhundhi, 32°18′37″N 57910 36 6x 100 2n=72 77°8′59″E/3050 14. Brachyactis pubescens Schnag, 32°14′22″N 58983 18 4x 99 2n=18 (DC.) Aitch. & C.B. 77°11′19″E/2450 Clarke (=B. robusta) Solang Village, 58981 18 4x 100 32°18′47″N 58982 18 4x 97 77°9′48″E/2750 15. Chrysanthemum Palchan, 32°18′47″N 57899 17 2x 68 2n=18, 18+3B, 36, leucanthemum Linn. 77°9′48″E/2400 54, 54+1-3B, 72 Palchan, 32°18′47″N 57902 17 2x 87 77°9′48″E/2400 Vashisht Village, 57904 17 2x 79 32°15′32″N 77°11′24″E/2475 Dhundhi, 32°18′37″N 57905 17 2x 89 77°8′59″E/3050 16. Cirsium arvense (L.) Palchan, 32°18′47″N 58992 17 2x 99 2n=34, 34+0-1B, Scop. 77°9′48″E/2400 34-36, 51, 68 Dhundhi, 32°18′37″N 58993 17 2x 100 77°8′59″E/3050 Dhundhi, 32°18′37″N 58994 17 2x 100 77°8′59″E/3050 17. Cnicus wallichii DC. Palchan, 32°18′47″N 58995 17 2x 100 2n=34 (=Cnicus wallichii 77°9′48″E/2400 Hook. f.) Schnag, 32°14′22″N 58996 17 2x 100 77°11′19″E/2450 Dhundhi, 32°18′37″N 58997 17+1B 2x 91 77°8′59″E/3050 18. Cosmos bipinnatus Cav. Solang Village, 59044 12 2x 99 2n=24, 24+1B 32°18′47″N 77°9′48″E/2750 59055 12 2x 100 59012 12 2x 98 Solang Nullah, 59056 12 2x 100 32°18′13″N 77°7′31″E/2750 19. Crepis japonica Benth. Vashisht Village, 58998 8 2x 100 2n=16, 18 32°15′32″N 77°11′24″E/2475 Solang Village, 58999 8 2x 98 32°18′47″N 77°9′48″E/2750 208 M. Kaur and V. K. Singhal Cytologia 80(2)

Table 1. Continued.

Localities of collections Accession Meiotic Pollen Ploidy Previous counts Taxon (Altitude in meters) number/s chromosome fertility level if any** with GPS coordinates (PUN)* number (‘n’) %age

20. Dandranthema boreale Solang Village, 58977 36 8x 99 2n=18, 36 (Makino) Ling ex 32°15′32”N 59041 36 8x 98 Kitamura 77°11′24”E/2750 (=Chrysanthemum boreale (Makino) Makino) 21. Erigeron annuus Press. Palchan, 32°18′47″N 58984 2n=27 3x 64 2n=18, 18+0–9B, 77°9′48″E/2400 20, 26, 27, 28, 36, Palchan, 32°18′47″N 58985 2n=27 3x 67 54 77°9′48″E/2400 Vashisht Village, 58986 2n=27 3x 76 32°15′32″N 77°11′24″E/2475 Dhundhi, 32°18′37″N 59034 2n=27 3x 71 77°8′59″E/3050 22. E. canadensis L. Palchan, 32°18′47″N 59030 9 2x 100 2n=18, 27, 36, 54 77°9′48″E/2400 Burua, 32°19′22″N 59037 9 2x 97 77°9′23″E/2450 23. Galinsoga parviﬂora Palchan, 32°18′47″N 59048 8 2x 99 2n=16, 24, 32, 48 Cav. 77°9′48″E/2400 Dhundhi, 32°18′37″N 59013 8 2x 97 77°8′59″E/3050 8 2x 100 24. Lactuca longifolia DC. BRO Office, 57918 8 2x 100 2n=16 32°19′22″N 77°9′23″E/2400 25. L. macrorhiza (Royle) Palchan, 32°18′47″N 59000 8 2x 100 2n=16 Hook. f. (=Cicerbita 77°9′48″E/2400 macrorhiza (Royle) Palchan, 32°18′47″N 59001 8 2x 99 Beauv.) 77°9′48″E/2400 Dhundhi, 32°18′37″N 59002 8 2x 100 77°8′59″E/3050 26. Ligularia ﬁscheri Dhundhi, 32°18′37″N 59018 30 2x 98 2n=60 (Ladeb.) Turcz. 77°8′59″E/3050 27. Myriactis nepalensis Palchan, 32°18′47″N 58987 18 4x 86 2n=36 Less. 77°9′48″E/2400 Dhundhi, 32°18′37″N 58988 18 4x 89 77°8′59″E/3050 Dhundhi, 32°18′37″N 58989 18 4x 78 77°8′59″E/3050 28. Myriactis wightii DC. Palchan, 32°18′47″N 58967 18 2x 79 2n=36 77°9′48″E/2400 58968 18 2x 98 29. Parthenium Solang Nullah, 57914 17 2x 100 2n=34, 36 hysterophorus Linn. 32°18′13″N 77°7′31″E/2750 57915 17 2x 100 57916 17 2x 100 30. Prenanthes brunoniana Solang Nullah, 59036 8 2x 98 2n=16, 18 Wall. ex DC. 32°18′13″N 77°7′31″E/2750 59046 8 2x 94 31. S. alatus Wall. ex DC. Dhundhi, 32°18′37″N 59022 20 8x 99 2n=40 77°8′59″E/3050 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 209

Table 1. Continued.

Localities of collections Accession Meiotic Pollen Ploidy Previous counts Taxon (Altitude in meters) number/s chromosome fertility level if any** with GPS coordinates (PUN)* number (‘n’) %age

BRO Office, 59038 20 32°19′22″N 77°9′23″E/2400 32. Senecio Palchan, 32°18′47″N 57917 20 8x 98 2n=40 chrysanthemoides DC. 77°9′48″E/2400 Palchan, 32°18′47″N 59019 20 8x 92 77°9′48″E/2400 Burua, 32°19′22″N 59020 20 8x 93 77°9′23″E/2450 Vashisht Village, 59021 20 8x 94 32°15′32″N 77°11′24″E/2475 33. Senecio ruﬁnervis DC. Solang Nullah, 57907 20 8x 97 2n=20, 36, 40 32°18′13″N 77°7′31″E/2750 Dhundhi, 32°18′37″N 59023 20 8x 99 77°8′59″E/3050 59024 20 8x 98 59025 20 8x 100 34. Siegesbeckia orientalis Solang Nullah, 57909 30 4x 92 2n=24, 30, 60 Linn. 32°18′13″N 77°7′31″E/2750 Dhundhi, 32°18′37″N 59014 30 4x 99 77°8′59″E/3050 35. Solidago virga-aurea Palchan, 32°18′47″N 58990 9 2x 100 2n=18, 44 Linn. 77°9′48″E/2400 Burua, 32°19′22″N 58991 9 2x 99 77°9′23″E/2450 36. Sonchus asper (L.) Hill Palchan, 32°18′47″N 59003 9 2x 99 2n=18, 18+3B, 32, (=S. oleraceous L. var. 77°9′48″E/2400 36 asper L.) 37. S. brachyotus DC. (=S. Solang Nullah, 59004 9 2x 98 2n=18, 36 arvensis L. var.glaber 32°18′13″N Haines) 77°7′31″E/2750 38. S. oleraceus Linn. Vashisht Village, 59005 16 4x 97 2n=18, 20, 32, 36 32°15′32″N 77°11′24″E/2475 39. Tagetes minuta Linn. Palchan, 32°18′47″N 59027 12 2x 100 2n=24, 48 77°9′48″E/2400 59050 12 2x 94 59051 12 2x 98 59052 12 2x 100 40. Taraxacum ofﬁcinale Palchan, 32°18′47″N 59006 8 2x 99 2n=8, 16, 18, 21, Wigg. 77°9′48″E/2400 23, 24, 24+01B, Vashisht Village, 59007 2n=24 3x 74 24+2B, 26, 27, 32, 32°15′32″N 34, 36, 37, 40, 48 77°11′24″E/2475 Solang Village, 57911 16 4x 83 32°18′47″N 77°9′48″E/2750 Solang Nullah, 59008 2n=40 5x 68 32°18′13″N 77°7′31″E/2750 Dhundhi, 32°18′37″N 59009 32 8x 97 77°8′59″E/ 3050 210 M. Kaur and V. K. Singhal Cytologia 80(2)

Table 1. Continued.

Localities of collections Accession Meiotic Pollen Ploidy Previous counts Taxon (Altitude in meters) number/s chromosome fertility level if any** with GPS coordinates (PUN)* number (‘n’) %age

41. Tussilago farfara Linn. Dhundhi, 32°18′37″N 59026 12 2x 100 2n=60, 72 77°8′59″E/3050 59042 12 2x 98 42. Xanthium strumarium BRO Office, 57913 18 4x 92 2n=16, 36 Linn. 32°19′22″N 77°9′23″E/2400 57906 18 4x 96 57908 18 4x 100 57912 18 4x 97

* Code of Herbarium of the Department of Botany, Punjabi University, Patiala, India, as per the “Index Herbariorum” by Holmgren and Holmgren (1998). ** Darlington and Wyile (1955), Fedorov (1969), Ornduff (1968, 1969), Bolkovskikh et al. 1969, Moore (1970, 1971, 1972, 1973, 1974, 1977), Löve and Löve (1980, 1982, 1986), Goldblatt (1981, 1984, 1985, 1988), Goldblatt and Johnson (1990, 1991, 1994, 1996, 1998, 2000, 2003, 2006), Kumar and Subramanian (1986), Khatoon and Ali (1993) and IAPT/IOPB and SOCGI Chromosome Reports and journals concerned with chromosome reports.

Achillea millefolium Linn. This erect perennial herb with a spreading rhizomatous growth is a native to temperate regions of the Northern Hemisphere in Asia, Europe, and North America. Meiotic investigations carried out on three accessions collected from Palchan (2,400 m), Solang Nullah (2,700 m) and Dhundhi (3,150 m) showed the diploid chromosome count of n=9 which was confirmed by the presence of nine bivalents at diakinesis (Fig. 1a) and 9 : 9 chromosomal distribution at A-1 (Fig. 1b). In one of the accession collected from Dhundhi (3,050 m), 31.79% PMCs showed the presence of one to two multivalents (Fig. 1c) and univalents (Fig. 1d), besides bivalents. The PMCs also showed some meiotic irregularities like chromatin stickiness (Fig. 1e) and out of plate bivalents (Fig. 1f) resulting into abnormal microsporogenesis (Fig. 1 g) and reduced pollen fertility (Fig. 1h). The presence of multivalents and reduced pollen fertility in this diploid cytotpe is attributed to structural heterozygosity for reciprocal translocations. Although the species has been investigated quite extensively from India and other parts of the world with an array of chromosome numbers (2n=18, 35, 36, 44, 45, 53, 54, 36+1B, 62-74, 63, 72, 36+0-2B, 54+0-3B, ca. 48, 54+B, 60-66, 81±5), the reciprocal translocations have been reported for the first time.

Anaphalis nepalensis (Spreng) Hand.–Mazz. This erect perennial herb is widely distributed in Bhutan, India, Myanmar and Nepal in alpine or sub-alpine grasslands, forest margins, scrubs, valleys, riverbanks, rocks, rock crevices and among lichens on slopes at an altitude of 2,400–4,500 m. Meiotic investigations made on the plants scored from Solang Nullah (2,700 m) and Dhundhi (3,050 m) revealed the existence of intraspecific tetraploid (n=14, Fig. 1i) and hexaploid cytotpes (n=21, Fig. 1j, k). Individuals of both the cytotypes depicted regular bivalents formation, normal microsporogenesis and cent per cent fertile pollen grain formation. The present study adds a new hexaploid cytotype (2n=42) for the first time to the already existing 4x, 2n=28 (Mehra and Remanandan 1969) and octoploid (2n=56, Malik and Gupta 2013) cytotypes in Indian populations.

Anaphalis triplinervis (Sims.) Clarke A perennial herb and a native to the Himalayas and South West China, this plant is widely distributed in India, Pakistan, Nepal, Bhutan and Xizang to China. The individuals collected from Dhundhi (3,050 m) showed a meiotic chromosome count of n=21 which was confirmed from the 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 211

Fig. 1. (a–r) (a–h) Achillea millefolium (a) PMC at diakinesis showing nine bivalents. (b) PMC showing 9:9 chromosomal distribution at A-1. (c) PMC depicting two chain type quadrivalents (arrowed). (d) PMC showing eight bivalents and two univalents (arrowed). (e) PMC showing stickiness in chromosomes at M-1. (f) PMC showing out of plate bivalent at M-1 (arrowed). (g) Tetrad with micronuclei (arrowed). (h) Larger fertile and smaller sterile pollen grains. (i–k) Anaphalis nepalensis (i) PMC with 14 : 14 chromosomal distribution at A-1. (j) PMC showing 21 bivalents at diakinesis. (k) PMC with 21 : 21 chromosomal distribution at A-1. (l) Anaphalis triplinervis PMC showing 21 : 21 chromosomal distribution at A-1. (m, n) Artemisia nilagirica (m) PMC showing 18 bivalents at M-1. (n) PMC showing 27 bivalents at M-1. (o–q) Artemisia salsoloides (o) PMC depicting 10 bivalents inclusive of one small sized bivalent (arrowed) at diakinesis. (p) PMC showing nine large and one small sized bivalent (arrowed). (q) PMC showing 10 : 10 equal chromosomal distribution including one smaller chromosome at A-1. (r) Brachyactis pubescens PMC showing 18 bivalents at M-1. 212 M. Kaur and V. K. Singhal Cytologia 80(2) presence of 21 : 21 chromosomes at A-1 (Fig. 1l). Based on x=7, the plants of Solang Valley exist at 6x level. Meiotic course in the individuals was observed to be perfectly regular resulting into normal sporad formation and cent per cent pollen fertility. Earlier, a tetraploid cytotype with 2n=28 has been reported by Sharma (1970) and Mehra and Remanandan (1975) from other parts of Indian Himalayas suggesting the existence of intraspecific polyploidy (4x, 6x).

Artemisia nilagirica (Clarke) Pamp. Also known as “Indian Wormwood”, this plant is an erect, hairy aromatic shrub, 1–2 m tall, and grows throughout India in hills up to 2,400 m. Investigations based on detailed male meiotic studies carried out on the individuals scored from three different localities of Palchan (2,400 m), Bahang (2,450 m) and Vashisht Village (2,475 m) revealed the first ever existence of two intraspecific cytotypes (4x, 6x) as confirmed from the presence of 18 (Fig. 1m) and 27 (Fig. 1n) bivalents at M-1. The diploid cytotype with 2n=18 (based on x=9) has already been reported by Mehra and Remanandan (1969, 1974) from the Kashmir Himalayas and recently by Bala and Gupta (2013) from Kangra district of Himachal Pradesh, India. It thus indicates that the species depicts the existence of intraspecific polyploidy (2x, 4x, 6x) in the Indian Himalayas. The meiotic course in both the polyploid cytotypes is perfectly regular resulting into normal tetrad formation and nearly 100% pollen fertility.

Artemisia salsoloides Willd. This perennial herb commonly grows in alpine grasslands, meadows and pastures between altitudinal range of 1,800–4,100 m in Russia, Pakistan, China and India. Present meiotic investigations have been analyzed from the accession collected from Palchan (2,400 m) which showed a meiotic chromosome count of n=10 which was confirmed from the presence of 10 bivalents inclusive of one small-sized at diakinesis (Fig. 1o), M-1 (Fig. 1p) and 10 : 10 chromosomes distribution at A-1 (Fig. 1q). Further meiotic course including microsporogenesis was noticed to be regular resulting into cent per cent pollen fertility. The species has been worked out for the first time from Himalayas in India and adds a new cytotype (2n=20) against the earlier diploid reports of 2n=18 recorded by Khatoon and Ali (1993) and Razaq et al. (1994) from Pakistan.

Brachyactis pubescens (DC.) Aitch. and C.B. Clarke Also described in some ﬂoras under B. robusta Benth., this plant grows as an erect annual and branched herb with leaves narrowed into a short petiole. The species is extensively distributed from Kashmir to Kumaon and Garhwal regions in the Western Himalayas between an altitudinal range of 1,200–4,200 m. Both the accessions collected from Schnag (2,450 m) and Solang Village (2,750 m) shared the same meiotic chromosome count of n=18 as confirmed by the presence of 18 bivalents at M-1 (Fig. 1r). Further meiotic course including segregation of chromosomes at A-1 (Fig. 2a) including microsporogenesis is regular leading to high pollen fertility (91–98%). Based on x=9, the individuals exist at 4x level. Earlier, Mehra and Remanandan (1969, 1974) have reported a diploid cytotype (2n=18) from Kashmir Himalayas. Therefore, the present study adds a new 4x cytotype and the existence of intraspecific polyploidy (2x, 4x) in Indian taxa.

Chrysanthemum leucanthemum Linn. A native to Europe and the temperate regions of Asia, this plant grows as a perennial herb with a creeping rhizomatous rootstock in meadows and fields, under-scrubs, open canopy forests and in disturbed areas. A meiotic chromosome count of n=18 (Fig. 2b) has been recorded presently on the basis of three accessions. Based on x=9, the studied individuals exist at 4x level. These individuals showed the presence of multivalents (Fig. 2c), laggards (Fig. 2d), chromatin bridges (Fig. 2e) and abnormal microsporogenesis with the formation of dyads, triads, polyads and sporads with 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 213 micronuclei (Fig. 2f–h) and consequently reduced pollen fertility (68% Fig. 2i). The 4x cytotype with similar type of meiotic behavior has also been reported by different workers from India (Mehra et al. 1965, Kumar 1982, Gupta and Gill 1984a, 1989, Gupta et al. 1989) and outside of India (Tahara 1915, 1921, Tischler 1934, Cooper and Mahony 1935, Negodi 1937, Rohweder 1937, Löve and Löve 1956, Gadella and Kliphuis 1963, 1966, 1967, Engelskjon 1979, Van Loon and Kieft 1980). The species is also known to have diploid cytotype with 2n=18 (Gadella and Kliphuis 1963, Mehra et al. 1965, Taylor and Mulligan 1968, Engelskjon 1979, Kumar 1982, Gupta and Gill 1984a, 1989, Gupta et al. 1989) 6x, 2n=54 (Dowrick 1952, Böcher and Larsen 1957, Mulligan 1958) and 8x, 2n=72 (Favarger 1963) cytotypes.

Cirsium wallichii DC.=(Cnicus wallichii Hook. f.) Commonly known as ‘Indian Thistle’, this is an erect sub-shrub, which occurs usually in Bhutan, Eastern Himalayas, Jammu and Kashmir, Western Himalayas and Nepal. Meiotic investigations carried out on three localities of Palchan (2,400 m), Schnag (2,475 m) and Dhundhi (3,050 m) showed a meiotic chromosome number of n=17 which was confirmed from the presence of 17 bivalents at M- 1 (Fig. 2j). The same diploid chromosome number has been reported by Mehra and Remanandan (1969, 1976), Gupta and Gill (1988, 1989), Gupta et al. (1989) and Bala and Gupta (2011). However, the presently studied individuals also showed the presence of 1B chromosome (Fig. 2k, l), which is a first ever report of B-chromosome for the species.

Dandranthema boreale (Makino) Ling ex Kitamura An annual erect herb and a native to regions of eastern Asia such as Korea, Japan, and China, this plant is also naturalized in certain parts of the Himalayas in India. The plant is used locally to treat vertigo in traditional medicine. The present chromosome count was determined on the basis of the meiotic study carried out on the accession collected from Solang Village (2,700 m) which revealed the presence of 36 bivalents at M-1 (Fig. 2m) and 36:36 chromosomal distribution at A-1 (Fig. 2n). Based on x=9, plants of Solang Valley exist at an octoploid level. Inspite of high chromosome number (n=36) and ploidy level (8x), the studied individuals depicted regular chromosome pairing and equal chromosomal segregation, resulting into normal tetrad formation and very high pollen fertility (98–99%). The species has been counted chromosomally for the first time from India. Besides, the present study adds a new cytotype (8x) to the already reported 4x (Dowrick 1952, Tanaka 1959, Byung-yun et al. 1996) and 6x (Kaneko 1957) cytotypes from outside of India.

Erigeron annuus Press. An erect annual herb with dense foliage, this plant is a native to eastern United States. The species commonly grows in disturbed areas of moist to slightly dry prairies, pastures and abandoned fields, areas along roadsides and disturbed open woods. Two accessions collected from Palchan (2,400 m) and Vashisht village (2,475 m) reﬂects the presence of a triploid cytotype with a meiotic chromosome count of 2n=27 as confirmed from the presence of 27 scattered chromosomes in the PMCs of mixed A-1 (Fig. 2o). Meiotic course in these triploid individuals (based on x=9) is highly abnormal characterized by the presence of unequal distribution of chromosomes at A-1 (Fig. 2p), presence of laggards at A-1 (Fig. 2q) and consequently abnormal sporads as dyads, triads, tetrads with micronuclei and polyads (Figs. 2r, 3a). Consequently, the individuals showed high pollen sterility (Fig. 3b). The triploid cytotype which is widely distributed in the Indian Himalayas and other regions of high hills outside of India has also been reported by a number of workers (Holmgren 1919, Okabe 1934, Bergman 1944, Huziwara 1958, Montgomery and Yang 1960, Solbrig et al. 1964, 1969, Arano 1965, Mehra et al. 1965, Hsu 1968, Dmitrieva 1987, 2000, Huber and Baltisberger 1992, Frey et al. 2003). 214 M. Kaur and V. K. Singhal Cytologia 80(2)

Fig. 2. (a–r) (a) Brachyactis pubescens PMC showing 36 chromosomes at mixed A-1. (b–i) Chrysanthemum leucanthemum (b) PMC showing 18 bivalents at M-1. (c) PMC depicted with 15 bivalents and one chain-shaped quadrivalent (arrowed) at M-1. (d) PMC showing laggards at late A-1 (arrowed). (e) PMC with chromatin bridges at A-1 (arrowed). (f) Dyad with micronucleus (arrowed). (g) Triad with a micronucleus (arrowed). (h) Polyad. (i) Fertile and sterile pollen grains. (j–l) Cirsium wallichii (j) PMC with 17 bivalents at M-1. (k) PMC showing 17 bivalents and 1B chromosome (arrowed). (m) PMC showing 17:17 chromosomal distribution and 1B chromosome (arrowed) at one pole at A-1. (m, n) Chrysanthemum boreale (m) PMC showing 36 bivalents at M-1. (n) PMC showing 36:36 chromosomal distribution at A-1. (o–r) Erigeron annuus (o) PMC with 27 chromosomes at mixed A-1. (p) PMC showing irregular distribution of chromosomes at A-1. (q) PMC showing laggards at A-1 (arrowed). (r) Dyad and Triad.

Ligularia fischeri (Ladeb.) Turcz. The species is distributed in damp shady places and sloping fields in Burma, Bhutan, China, India, Japan, Mongolia, North Korea, Nepal, South Korea and Russia. Its leaves have been used to treat jaundice, scarlet fever, rheumatoid arthritis and hepatic diseases (Choi 1991). Detailed meiotic 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 215 studies showed a chromosome count of n=30 which was confirmed by the presence of 30 bivalents at diakinesis (Fig. 3c). Further meiotic course is characterized by equal chromosomal distribution at A-1 resulting into normal tetrads and subsequently equal sized pollen grains and cent per cent pollen fertility. The species which has been studied chromosomally for the first time from India, confirms the earlier reports of2n=60 by workers from Russia (Gurzenkov 1973, Rudyka 1990, Probatova 2005). Liu (2004) has reported an aneuploid chromosome count of 2n=58 from eastern Qinghai-Tibet Plateau.

Myriactis wightii DC. The species, which grows in forests on slopes, grasslands and streamsides in the Himalayas at altitudes of 1,900–3,600 m, is an annual herb with hemispheric ﬂower heads having a large yellow centre with small white ray-ﬂorets on the periphery. The studied accession depicted a meiotic chromosome count of n=18 which was confirmed from the presence of 18 bivalents at M-1 (Fig. 3d). A few PMCs also showed the presence of one quadrivalent besides 16 bivalents (Fig. 3e). Meiotic course in the studied individuals showed the presence of other irregularities like out of plate bivalent (Fig. 3f), laggards at anaphases/telophases (Fig. 3 g) resulting into abnormal sporads (Fig. 3h) and heterogenous sized pollen grains (Fig. 3i) with a significant reduction in pollen fertility (79%).

Taraxacum officinale Wigg. Taraxacum ofﬁcinale (the dandelion weed) is a perennial herb commonly found in the temperate regions of the world in lawns, along roadsides, disturbed banks and shores of waterways, and other areas with moist soils. The species which is very widely distributed in the Himalayas is highly variable morphogenetically constituting a complex species. It has been worked out quite extensively for chromosome counts from the Himalayas in India and mountain regions outside of India, depicting an array of chromosome numbers (2n=16, 18, 21, 23, 24, 26, 27, 32, 34, 36, 37, 40, 48) involving intraspecific aneuploidy and/or polyploidy. Present detailed male meiotic investigations made on individual plant basis collected from Palchan (2,400 m), Vashisht village (2,475 m), Solang Nullah (2,700 m), Solang Village (2,750 m) and Dhundhi (3,050 m) revealed the presence of five different cytotypes, the diploid (2n=16, Fig. 3j), triploid (2n=24, Fig. 3k), tetraploid (2n=32, Fig. 3l), pentaploid (2n=40, Fig. 3 m) and octoploid (2n=64, Fig. 3q). However, the individuals of these intraspecific cytotypes are morphologically indistinguishable. Of these, the pentaploid cytotype has been found for the first time from North India against the earlier report of 2n=40 by Mehra and Remanandan (1969) from South India. The octoploid cytotype (2n=8x=64) has been recorded in the species for the first time. Among these, the meiotic course is highly abnormal in 3x and 5x cytotypes characterized by the high frequency of univalents (Fig. 3k), laggards (Fig. 3n), abnormal sporad formation (Fig. 3o) and pollen sterility (74% and 68%, respecively, Fig. 3p).

Tussilago farfara Linn. A perennial herb native to several locations in Europe and Asia, this plant is often found growing in waste and disturbed places and along roadsides and paths in Indian Himalayas. Meiotic details carried out on the accession scored from Dhundhi (3,050 m) revealed a chromosome count of n=12 which was confirmed by the presence of 12 bivalents at M-1 (Fig. 3r) andequal chromosomal distribution at mixed A-II (Fig. 3s). Further meiotic course including sporad formation in this diploid taxon was perfectly regular leading to high pollen fertility (98%). Based on x=12, the presently studied individuals exist at 2x level. The species which has been counted chromosomally for the first time from India adds a new cytotype (2x) to the already existing polyploid chromosome counts of 2n=60 (Langlet 1936, Delay 1947, Löve and Löve 1956, Gadella 216 M. Kaur and V. K. Singhal Cytologia 80(2)

Fig. 3. (a–s) A, B Erigeron annuus (a) Dyad with a micronucleus (arrowed). (b) Fertile and sterile pollen grains. (c) Ligularia fischeri PMC showing 30 bivalents at diakinesis. (d, e) Myractis wightii (d) PMC showing 18 bivalents at M-1. (e) PMC showing one quadrivalent (arrowed) along with 16 bivalents. (f) PMC depicting out of plate bivalent (arrowed). (g) PMC with laggards at A-II (arrowed). (h) Tetrad with a micronucleus (arrowed). (i) Heterogenous sized pollen grains. (j–q) Taraxacum officinale (j) PMC showing eight bivalents at M-1. (k) PMC showing five bivalents and 14 univalents. (l) PMC showing 16 bivalents at diakinesis. (m) PMC with 40 chromosomes at mixed A-1. (n) PMC showing laggards at A-1 (arrowed). (o) Dyad. (p) Heterogenous sized pollen grains (q) Octoploid PMC showing 32 bivalents. (r, s) Tussilago farfara (r) PMC showing 12 bivalents at M-1. (s) PMC showing 12 : 12 : 12 : 12 chromosomes at A-II. and Kliphuis 1966, Knaben and Engelskjøn 1967, Leveque and Gorenflot 1969, Májovský 1970, Loeve and Kjelloqvist 1974, Van den Brand et al. 1979, Arohonka 1982, Dmitrieva and Parfenov 1985, Kuzmanov et al. 1986, Kapoor et al. 1987, Hill 1989, Parfenov and Dmitrieva 1988, Hollingsworth et al. 1992, Druskovic and Lovka 1995, Mĕsiček and Jarolímová 1992, Liu 2000, 2015 Cytomorphological Diversity in Some Members of Family Asteraceae 217

Lövkvist and Hultgard 1999, Probatova et al. 2001) and 2n=72 (Hagerup 1941) from outside of India. Perusal of earlier chromosomal data and present investigations revealed that out of the 42 presently analyzed species, as many as 18 species (42.85%) exist at different ploidy levels. Two or more than two intraspecific cytotypes at different ploidy levels are present in Achillea millefolium (2x, 3x, 4x, 5x, 6x, 7x, 8x, 9x), Ageratum conyzoides (2x, 4x), Anaphalis adnata (2x, 4x), A. nepalensis (4x, 6x, 8x), A. triplinervis (4x, 6x), Artemisia nilagirica (2x, 4x, 6x), A. scoparia (2x, 4x), Bidens biternata (2x, 6x), B. pilosa (2x, 3x, 4x, 6x, 8x), Brachyactis pubescens (2x, 4x), Chrysanthemum leucanthemum (2x, 4x, 6x, 8x), Cirsium arvense (2x, 3x, 4x), Dandranthema boreale (2x, 4x), Erigeron annuus (2x, 3x, 4x, 6x), Galinsoga parviflora (2x, 3x, 4x, 6x), Sonchus asper (2x, 4x), S. brachyotus (2x, 4x), S. oleraceus (2x, 4x), Siegesbeckia orientalis (2x, 4x), Tagetes minuta (2x, 4x), Taraxacum officinale (2x, 3x, 4x, 5x, 6x, 8x), Senecio rufinervis (4x, 8x), and Tussilago farfara (2x, 5x, 6x). Intraspecific chromosomal variations involving aneuploidy and/ or polyploidy is illustrated in Achillea millefolium (2n=18, 35, 36, 44, 45, 48, 53-54, 54, 60-66, 62- 74, 63, 72, 74, 81), Crepis japonica (2n=16, 18), Erigeron annuus (2n=18, 20, 26, 27, 28, 36, 54), Parthenium hysterophorus (2n=34, 36), Solidago virga-aurea (2n=18, 44), Sonchus asper (2n=18, 32, 36), S. oleraceus (2n=18, 20, 32, 36), Taraxacum officinale (2n=16, 18, 21, 23, 24, 26, 27, 32, 36, 37, 40, 48), Ageratum conyzoides (2n=20, 36, 40), Bidens pilosa (2n=24, 36, 40, 46, 48, 70, 72, 76, 96), Siegesbeckia orientalis (24, 30, 60), Senecio rufinervis (2n=20, 36, 40) and Xanthium strumarium (2n=16, 36). Achillea millefolium and Taraxacum officinale seems to constitute species complexes and are well established in different parts of the world. Introgression and hybridization in these species seem to be quite frequent, making identification of the different cytotypes difficult, uncertain or even impossible (Baltisberger 2006). The wide distribution of triploid cytotype of E. annuus in the Himalayas could also be attributed to its successful propagation through apomixis (McDonald 1927, Gustafsson 1946, Fagerlind 1947).

Acknowledgements

Authors are thankful to the University Grants Commission, New Delhi for providing financial assistance under the DRS SAP I, II & III and ASIST programme. Senior author is also thankful for providing fellowship under Maulana Azad National Fellowship Scheme for Minority Students 2011–2012 (Award letter No. F1–17.1/2011/MANF-SIK-HAR-4278/(SA-III/Website). Thanks are also due to the Head, Department of Botany for providing necessary laboratory, library and internet facilities.

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