New chromosome counts and evolutionary tendencies in some dicots analyzed from Parvati Valley, Kullu district, Himachal Pradesh

ABSTRACT

The present study covers chromosome counts, male meiosis and pollen fertility in 164 species of dicots from the Parvati Valley, Kullu district, Himachal Pradesh. Gathered cytological information generates first ever chromosome counts, new diploid/polyploid cytotypes and varied chromosome counts. As many as 41 species (25%) showed intraspecific euploid cytotypes. Role of aneuploidy causing chromosomal variation is apparent from the existence of 71 species (43.29%) depicting aneuploid/dysploid cytotypes at diploid and/or polyploid levels and 114 genera showing dibasic/polybasic nature. The existence of abnormalities in several species resulted in the production of genetically imbalanced and sterile pollen grains. The viable gametes with variable chromosome numbers might have played a part in the origin of aneuploids, polyploids and species complexes. Also the non-viable gametes produced as a consequence of meiotic irregularities might have resulted in reduction of reproductive success of species through seeds. Consequently, the plants have adopted alternate means of propagation through asexual and vegetative modes which is quite prevalent in the plants of area.

KEYWORDS:

• Chromosome counts
• male meiosis
• dicots
• Parvati Valley
• Himachal Pradesh

1. Introduction

Parvati Valley, situated in Kullu district (Himachal Pradesh) along the River Parvati between 31°20ʹ21ʺ–32°25ʹ00ʺ N longitude and 76°56ʹ30ʺ–77°52ʹ20ʺ E latitude, is approximately 130 km long and 1.5 km wide. The altitude ranges between 1100 m at Bhuntar town, a confluence point of Parvati and Beas rivers, to Manatalai Lake at 4100 m. The climate varies from hot and sub-tropical in the southern lower tracts (600–900 m) to warm temperate (900–1800 m), cool temperate (1900–2400 m) and cold alpine to glacial (2400–4800 m) in the northern and eastern mountain ranges. The valley experiences high rainfall (800–900 m) in July–September and heavy snowfall (8–9 m) during winter months of January–March. The valley, which is known for its rich vegetation, supports dense forests of pines, deodar, oaks, spruce, fir, alder and rhododendron. The geographic location, varied climate, topography, altitudinal range and high precipitation in the form of rain and snow have contributed significantly toward the richness in plant diversity and dense forests. The valley has attracted a number of plant collectors and taxonomists. While compiling the flora of Kullu district, Dhaliwal and Sharma (1999) have included a large number of plants from the Parvati Valley. On the basis of extensive and intensive cytomorphological surveys carried out during the period between 2010 and 2015, some interesting results have been reported in the form of the first ever chromosome counts, varied chromosome records, intraspecific euploid and dysploid cytotypes, imbalanced polyploids, structural hybrids and aberrant genotypes (Gupta et al. 2010, 2017; Himshikha et al. 2010, 2017; Rana et al. 2012; Singhal et al. 2012, 2014, 2017; Kumar et al. 2014a, 2014b, 2015; Kaur et al. 2017). The present communication includes cytological information on 164 species. The aims of study were to (i) record the exact chromosome number in the meiocytes at different stages; (ii) analyze the detailed male meiotic course including chromosomal pairing and segregation to determine the base number, ploidy level and type of polyploidy, and to detect structural changes that a species might have undergone during evolution; (iii) estimate pollen fertility and pollen size variability if any; and (iv) unravel the extent of morphological and cytological variability in the flowering plants of the valley.

2. Materials and methods

Wild accessions of the presently analyzed species were collected from the various localities at different altitudes in the Parvati Valley during the months of April-September. For meiotic and pollen grain studies, floral buds were fixed in a freshly prepared Carnoy’s fixative (mixture of alcohol, chloroform and acetic acid in a volume ratio 6:3:1) for 24 h and preserved in 70% ethanol in a refrigerator. Meiocytes preparations were made by squashing the anthers in 1% acetocarmine and observed at different stages of prophase-1, metaphase-1, anaphase-1/II, telophases-1/II and sporads. Pollen fertility was estimated through stainability tests by smearing the mature anthers in glycerol-acetocarmine (1:1) mixture. Well-filled pollen grains with stained nuclei were scored as apparently fertile, while shriveled and flaccid pollen grains with unstained or poorly stained cytoplasm as sterile. Cytologically analyzed plants were identified by consulting the regional floras. The plants were re-validated by comparing the specimens in the Herbarium, Northern Circle, Botanical Survey of India, Dehra Dun. Duly identified specimens were deposited in the Herbarium, Department of Botany, Punjabi University, Patiala. Photomicrographs of meiocytes, sporads and pollen grains were taken from temporary preparations using Leica Microsystems, Wetzlar, Germany and Nikon 80i Eclipse microscope, Melville, USA. The information on 164 species (397 accessions) falling under 114 genera and 37 families of dicotyledons covering sites of collection, vouchers (PUN), gametic chromosome number, meiotic course, ploidy level, pollen fertility and previous chromosome counts is provided in Table 1.

Figure 1. (a-x ) Gametic chromosome counts . 1 (a) Herpetospermum pedunculosum, PMC showing 10 bivalents at M- I. (b) Bilderdykia pterocarpa, PMC showing 40 bivalents at diakinesis . (c) Incarvillea arguta, PMC showing 11 bivalents at M- I. (d) Phagnalon niveum, PMC showing nine bivalents at M- I. (e) two Androsace lanuginosa, PMCs showing 10 bivalents at M- I. (f) Crepis foetida, PMC showing five bivalents at M- I. (g) Delphinium pyramidale, PMC showing eight bivalents at M- I. (h) Impatiens micranthemum, PMC showing nine bivalents at M- I. (i) I. spirifer, PMC showing seven bivalents at M- I. (j) Potentilla leuconata, PMC showing seven bivalents at M- I. (k) Senecio pedunculatus, PMC showing 20 bivalents at M- I. (l) Trigonella pubescens, PMC showing eight bivalents at M- I. (m) Geranium lucidum, PMC showing 14 bivalents at M- I. (n) Gnaphalium affine, PMC showing 7:7 chromsomes at M-II. (o) Nepeta floccosa PMC showing 18 bivalents at diakinesis . (p) Corydalis thyrsiflora, PMC showing 7:7 chromosomes at A- I. (q) Gerbera lanuginosa, PMC showing 24:24 chromosomes at A- I. (r) Gentiana argentea, PMC showing 9:9 chromosomes at A- I. (s) Inula grandiflora, PMC showing 16 bivalents at M-I . (t) Lepidium sativum, PMC showing 16 bivalents at M- I. (u) Potentilla desertorum, PMC showing 14 bivalents at M- I. (v) Roylea cincerea PMC showing 10:10 chromosomes at A- I. (w) Rumex nepalensis, PMC showing 40 bivalents at diakinesis. (x) A PMC showing 60 bivalents at diakinesis. Scale bars = 10 μm.

3. Results and discussion

3.1. Chromosome counts

Apart from the first ever chromosome counts at generic and species level and new intraspecific dysploid/polyploid cytotypes, the rest of the records substantiate the earlier reports. Four genera namely, Herpetospermum Wall. (H. pedunculosum (Ser.) C.B. Clarke (n = 10; Figure 1(a)). Bilderdykia Dumort. (B. pterocarpa (Wall. ex Meisn.) Greene, (n = 40; Figure 1(b)), Incarvillea Juss. (I. arguta Royle, (n = 11; Figure 1(c)) and Phagnalon Cass. (P. niveum Edgew.) (n = 9; Figure 1(d)), and 10 species, Androsace lanuginosa Wall. (n = 10; Figure 1(e)), Crepis foetida L. (n = 5; Figure 1(f)), Delphinium pyramidale Royle (n = 8; Figure 1(g)), Impatiens micranthemum Edgew. (n = 9; Figure 1(h)), I. spirifer Hook. f. & Thoms. (n = 7; Figure 1(i)), Lonicera hypoleuca Decne. (n = 18), Potentilla leuconata D. Don (n = 7; Figure 1(j)), Senecio pedunculatus Edgew. (n = 20; Figure 1(k)) and Trigonella pubescens Baker (n = 8; Figure 1(l)) are worked out chromosomally for the first time on a worldwide basis. The chromosome counts are new for Indian taxa of Geranium lucidum L. (n = 14; Figure 1(m)), Gnaphalium affine D. Don (n = 7; Figure 1(n)), and Nepeta floccosa Benth. (n = 18; Figure 1(o)). New intraspecific diploid/polyploid cytotypes and varied chromosome counts in comparison to the earlier findings have been reported in Corydalis thyrsiflora Prain (n = 7), Gentiana argentea (Royle ex D. Don) DC. (n = 9), Geranium lucidum (n = 14), Gerbera lanuginosa (Wall. ex DC.) Benth. (n = 24), Gynura cusimbua (D. Don) Moore (n = 8), Impatiens thomsonii Hook. f. (n = 9), Lespedeza juncea (L.f.) Pers. (n = 11), Roylea cinerea (D. Don) Baill. (n = 10) and Salvia lanata Roxb. (n = 9).

Figure 2. (a-i), Meiotic abnormalities . (a) Deutzia staminea PMC showing chain-shaped quadrivalent at diakinesis (arrowed) . (b) Fagopyrum dibotrys PMC showing chain-shaped quadrivalent at metaphase-I (arrowed). (c–i) araxacum officinale: (c) univalents at diakinesis stage (arrowed ); (d , e) chromatin transfer between neighboring PMCs (arrowed ); (f) a PMC showing chromatin stickiness; (g) a triad ; (h) a tetrad with a micronucleus (arrowed ); (i) variable sized fertile/stained pollen grains. Scale bars = 10 μm.

The analyzed accessions of Corydalis thyrsiflora showed the gametic chromosome count of n = 7 which was confirmed from the presence of 7:7 equal chromosome distribution (Figure 1(p)). In spite of regular meiotic course and normal sporads, heterogeneous sized pollen grains were noticed. On the basis of size, pollen grains were categorized as small (19.34–20.48 × 19.27–19.59 µm, 17.05%), typical (24. 56–24.77 × 22.98–23.42 µm, 45.28%) and large-sized (32.56–32.80 × 27.82–31.33 µm, 37.67%). Present analysis adds a new dysploid cytotype (2n = 14) against the earlier reports of 2n = 16 by Kumar and Singhal (2011, 2012) from Lahaul-Spiti and by Rani (2012) from Kangra district of Northwest Himalayas in India.

The gametic chromosome count of n = 24 (Figure 1(q)) for Gerbera lanuginosa from the valley adds a new tetraploid cytotype to the already existing diploid cytotype (n = 12) reported by Gupta and Gill (1989) and Gupta et al. (1989) from Shiwalik hills. The species is also known to have other chromosome counts of 2n = 36 reported by Bala and Gupta (2013) from Kangra district, Himachal Pradesh and 2n = 46 by Mehra et al. (1965) and Mehra and Remanandan (1976) from other parts of Himalayas in India. It thus indicates that the species depicts a considerable amount of chromosomal diversity involving intraspecific euploid (2x, 3x, 4x) and dysploid (2n = 46, 48) cytotypes.

Gynura cusimbua, which grows as a tall perennial herb, showed a varied diploid chromosome count of n = 8 against the earlier report of 2n = 18 by Mehra and Sidhu (1960) from North India. Mehra et al. (1965) also detected the existence of intraspecific diploid (2n = 20) and tetraploid (2n = 40) cytotypes based on x = 10. It seems that the species has exploited both dysploidy (2n = 18, 20) and euploidy (2x, 4x) during the course of evolution.

Gentiana argentea, an important medicinal herb referred locally as “Karru,” is analyzed meiotically on the basis of three accessions. All the accessions uniformly shared the same diploid chromosome number, 2n = 18, as confirmed on the basis of 9:9 chromosomes distribution at A-I (Figure 1(r)). Meiotic course was noticed to be regular, resulting in equal sized 100% fertile pollen grains. The present analysis adds a new intraspecific dysploid cytotype (2n = 18) against the previous reports of 2n = 20 (Mehra and Vasudevan 1972) and Bala (2012) from other regions of Northwest Himalayas in India.

Geranium lucidum has been worked out for chromosome number for the first time from India. Present analysis on the basis of accession collected from the valley adds a new intraspecific cytotype at 2x level with 2n = 28 to the already existing chromosome counts of 2n = 20, 40, 42, 60 (Warburg 1938; Uhrikova and Májovsky 1980; Strid and Franzén 1981; Aryavand 1983; Galland 1988; Luque and Diaz Lifante 1991; Hollingsworth et al. 1992; Dempsey et al. 1994; Albers and Pröbsting 1998; Petrova and Stanimirova 2003).

We have reported for the first time the existence of 2x, 4x individuals in Inula grandiflora Willd. (2n = 32; Figure 1(s)) from Malana Village. In comparison to 2x, the 4x plants possessed larger size leaves and capitula. The 4x plants also differ from the 2x in possessing comparatively larger sized stomata, trichomes and pollen grains (Table 2). Previous surveys from India and outside of India have reported the presence of only diploid individuals with a chromosome count of 2n = 16 (Sokolovskaya and Strelkova 1940; Shetty 1967; Gvinianidze and Avazneli 1982; Gadnidze et al. 1998).

Table 1. Data on locality with altitude, vouchers (PUN*), gametic chromosome number (n), ploidy level, pollen fertility (%), and previous reports of the presently investigated species.

	Taxon	Locality with altitude (m)	Vouchers (PUN*)	Gametic chromosome number (n)	Ploidy level	Meiotic course	Pollen fertility (%)	Previous chromosome reports**
Subclass Polypetalae; Family: Ranunculaceae
1.	Aconitum heterophyllum Wall.	Malana (2652)	57323	8	2x	Normal	96	2n = 16
2.	Anemone rivularis Buch.-Ham. ex DC.	Manikaran Sahib (2090) Satyam Tunnel (2750)	58346 58345	8 8	2x 2x	Abnormal with cytomixis Normal	87 91	2n = 14, 16, 24, 28, 48
3.	Clematis connata DC.	Malana (2652) Satyam Tunnel (2750) Chander-khani Pass (3650)	57303 57233 57304	8 8 8	2x 2x 2x	Cytomixis Cytomixis Cytomixis	79 74 93	2n = 16
4.	C. grata Wall.	Shaat (1600) Chauki (2500) Braagha (2600) Malana (2652) Gurthigarh (2660) Satyam Tunnel (2750)	56334 57223 56335 56336 56083 56333	8 8 8 8 8 8	2x 2x 2x 2x 2x 2x	Cytomixis Cytomixis Cytomixis Cytomixis Cytomixis Cytomixis	87 85 79 78 69 71	2n = 16, 16+0-1B
5.	Delphinium pyramidale Royle (=D. elatum L.)	Malana (2652)	58663	8	2x	Cytomixis, non-synchronous disjunction, chromatin bridges, abnormal sporads	94	First ever chromosome record for the species
6.	Ranunculus hirtellus Royle ex D. Don	Chhagna (1700) Chauki (2500) Sheela Village (2650)	58374 58375 58376	16 16 16	4x 4x 4x	Normal Normal Cytomixis	97 94 80	2n = 16, 24, 28, 32
7.	R. laetus Wall (= R. distans Royle ex D. Don)	Jari (1624) Barshani (2150) Tosh (2400) Kasol (2614) Malana (2652)	56073 56064 56075 56045 56078	14 14 14 14 14+0-2B	4x 4x 4x 4x 4x	Cytomixis Spindle abnormalities Cytomixis Cytomixis Cytomixis	84 79 72 68 71	2n =  16, 28, 32, 32+0-3B, 42, 56
8.	Thalictrum javanicum lume (= T. glyphocarpum Wight & Arn.)	Pulga (2100) Kasol (2614) Manikaran Sahib (2090)	58044 58045 58594	7 7 7	2x 2x 2x	Normal Normal Normal	90 86 95	2n = 14, 16, 28
Family: Berberidaceae
9.	Berberis glaucocarpa Stapf	Tosh (2400) Kasol (2614)	56052 56046	14 14	2x 2x	Normal Normal	100 98	2n = 28
Family: Fumariaceae
10.	Corydalis thyrsiflora Prain (=C. gortschakovii Hook.f.)	Sheela Village (2650) Malana (2652)	57155 57175	7 7	2x 2x	Normal Normal	98 100	2n = 16
Family: Brassicaceae
11.	Lepidium sativum L.	Pulga (2100) Rashol (2700)	58658 58673	16 16	4x 4x	Normal Normal	93 100	2n = 12, 16, 24
12.	Thlaspi arvense L.	Kheerganga (2960)	56060	7	2x	Normal	100	2n = 14
Family: Violaceae
13.	Viola canescens Wall. ex Roxb. (=V. serpens Wall. ex Roxb. var. canescens (Wall. ex Roxb.) Hook.f. & Thoms.)	Pulga (2100) Tosh (2400) Malana (2652) Kheerganga (2960)	56114 56074 56061 56059	9 9 9 9	2x 2x 2x 2x	Normal Normal Normal Normal	100 100 100 97	2n = 12, 18, 48
Family: Caryophyllaceae
14.	Lychnis indica Benth.	Malana (2652)	57927	24	4x	Normal	93	2n = 24, 48
15.	Silene vulgaris (Moench) Garcke (=S. cucubalus Wibel)	Tosh (2400) Rashol (2700) Malana (2652) Nareng (2700) Satyam Tunnel (2750) Kheerganga (2960)	57403 57404 57402 58024 58025 58035	12 12 24 24 24 24	2x 2x 4x 4x 4x 4x	Normal Normal Normal Normal Normal Normal	93 100 93 87 90 83	2n = 24, 24+0-1B, 48
16.	Stellaria media (L.) Vill.	Jari (1624) Kasol (2614) Malana (2652)	56328 56047 56329	13 13 13	2x 2x 2x	Normal Normal Normal	95 98 96	2n = 18, 26, 28, 40, 42, 44
Family: Hypericaceae
17.	Hypericum elodeoides Choisy	Kasol (2614)	57222	9	2x	Normal	100	2n = 16, 18, 32
Family: Geraniaceae
18.	Geranium lucidum L.	Kasol (2614)	58680	14	2x	Normal	100	2n = 20, 40, 42, 44, 60
19.	G. nepalense Sweet Morphovariant with purple flowers (MVI) Morphovariant with white flowers (MVII)	Manikaran Sahib (2090) Tosh (2400)	57333 58395	14 14	2x 2x	Normal Normal	100 100	2n = 26, 28
20.	G. wallichianum D. Don ex Sweet	Chauki (2500)	58677	14	2x	Normal	100	2n = 26, 28, 56
Family: Balsaminaceae
21.	Impatiens amphorata Edgew. (= I. bicolor Royle) (= I. umbrosa Edgew.)	Malana (2652) Satyam Tunnel (2750)	58403 58411	7 9	2x 2x	Non-synchronous disjunction and chromatin bridges in both the accessions	96 90	2n = 14, 18, 32
22.	I. bicornuta Wall.	Chauki (2500) Nareng (2700)	57313 57314	9 9	2x 2x	Normal Normal	99 100	2n = 14, 16, 18
23.	I. brachycentra Kar. & Kir.	Barshani (2150) Braagha (2600) Nareng (2700)	58380 57312 57311	7 7 7	2x 2x 2x	Normal Non-synchronous disjunction Normal	2x 2x 2x	2n = 14, 16
24.	I. glandulifera Royle (= I. roylei Walp.)	Braagha (2600) Nareng (2700)	57308 57310	9 9	2x 2x	Normal Normal	100 100	2n = 18, 20
25.	I. laxiflora Edgew.	Shaat (1600) Sarsari (1700)	57301 57300	7 7	2x 2x	Normal Late disjunction, chromatin bridges	97 98	2n = 12, 14, 16
26.	I. micranthemum Edgew.	Sheela Village (2650)	57309	9	2x	Normal	100	First ever chromosome record for the species
27.	I. scabrida DC.	Jari (1624) Braagha (2600) Kasol (2614)	57307 57203 57202	7 7 7	2x 2x 2x	Normal Univalents, irregular chromosome distribution Normal	85 64 95	2n = 12, 14, 16, 18, 20
28.	I. spirifer Hook.f.& Thoms.	Satyam Tunnel (2750)	58643	7	2x	Non-synchronous disjunction, chromatin bridges	91	First ever chromosome record for the species
29.	I. thomsoni Hook.f.	Malana (2652)	58381	9	2x	Non-synchronous disjunction, chromatin bridges	96	2n = 12, 14, 16, 20
Family: Rutaceae
30.	Boenninghausenia albiflora (Hook.f.) Reichb. ex Meissn.	Shaarni (1750)	58667	10	2x	Normal	100	2n = 18, 20
31.	Zanthoxylum armatum DC. (=Z. alatum Roxb.)	Tosh (2400) Chauki (2500) Malana (2652) Nareng (2700)	56099 56101 56095 56100	33 33 33 33	4x 4x 4x 4x	Normal Normal Normal Precocious disjunction, inter-chromosomal connections	97 100 100 98	2n = 66
Family: Papilionaceae
32.	Astragalus chlorostachys Lindl.	Pulga (2100) Barshani (2150) Kasol (2614) Malana (2652)	56339 56338 56049 56149	8 8 8 8	2x 2x 2x 2x	Normal Late disjunction, chromatin stickiness Normal Normal	100 95 99 100	2n = 16
33.	A. graveolens Buch.-Ham. ex Benth.	Jari (1624)	58372	8	2x	Cytomixis	98	2n = 16
34.	A. leucocephalus Grah. ex Benth.	Jari (1624) Kasol (2614)	58410 58409	8 8	2x 2x	Normal Normal	100 100	2n = 16
35.	Desmodium concinnum DC.	Malana (2652)	56111	11	2x	Normal	98	2n = 22
36.	D. podocarpum DC.	Malana (2652)	56110	11	2x	Normal	100	2n = 22
37.	D. tiliaefolium (D. Don) G.Don (=D. elegans DC.) (= Hedysarum tiliaefolium D. Don)	Pulga (2100)	58384	11	2x	Normal	100	2n = 22
38.	Lathyrus aphaca L.	Jari (1624) Sarsari (1700) Barshani (2150) Malana (2652)	56070 56108 56113 56107	7 7 7 7	2x 2x 2x 2x	Normal Normal Normal Normal	98 100 100 100	2n = 14, 28
39.	Lespedeza juncea (L.f.) Pers.var. variegata (Camb.) Ali	Jari (1624)	58654	11	2x	Normal	100	2n = 18, 20
40.	Lotus corniculatus L.	Kasol (2614)	56051	6	2x	Cytomixis	95	2n = 12, 24, 28, 32, 36
41.	Parochetus communis Buch.-Ham. ex D. Don.	Pulga (2100) Satyam Tunnel (2750)	57160 57161	8 8	2x 2x	Precocious disjunction Precocious disjunction	100 98	2n = 16
42.	Trifolium pratense L.	Braagha (2600) Nareng (2700)	58385 58368	7 7	2x 2x	Normal Normal	100 100	2n = 14, 16, 22, 26, 27, 28, 29, 32, 48
43.	T. repens L.	Sarsari (1700) Manikaran Sahib (2090) Pulga (2100)	56337 56053 56054	16 16 16	4x 4x 4x	Normal Cytomixis Cytomixis	100 85 88	2n = 16, 18, 22, 30, 32, 48, 64
44.	Trigonella pubescens Edgew.	Malana (2652)	58653	8	2x	Normal	100	First ever chromosome report for the species
45.	Vicia hirsuta (L.) Gray	Jari (1624) Kasol (2614)	58648 56063	7 7	2x 2x	Cytomixis Normal	85 89	2n = 12, 14, 28
46.	V. sativa L.	Jari (1624) Kasol (2614)	57197 56062	6 6	2x 2x	Normal Inter-bivalent connections	98 100	2n = 12, 14, 24, 28
Family: Rosaceae
47.	Agrimonia eupatoria L. (=A. pilosa Ledeb. var. nepalensis (D. Don) Nakai)	Pulga (2100) Tosh (2400) Chauki (2500) Kasol (2614) Malana (2652) Rashol (2700) Gurthigarh (2660) Kheerganga (2960) Nareng (2700) Braagha (2600)	58036 58023 56085 57945 56081 58020 58021 58022 58037 57944	28 28 28 28 28 28 28 28 42 42	4x 4x 4x 4x 4x 4x 4x 4x 6x 6x	Normal Normal Normal Normal Normal Normal Normal Normal Normal Normal	95 97 98 100 100 93 98 100 97 94	2n = 28, 56, 70, 84, 84+1B
48.	Filipendula vestita (Wall. ex G. Don) Maxim. (=Spiraea vestita Wall. ex G. Don)	Malana (2652) Rashol (2700) Kheerganga (2960)	57205 57224 57206	7 7 7	2x 2x 2x	Normal Normal Normal	100 99 98	2n = 14, 18
49.	Potentilla argyrophylla Wall. ex Lehm. (=P. atrisanguinea Lodd.)	Malana (2652)	58660	42	12x	Cytomixis	93	2n = 28, 42, 56, 63, 74, 84
50.	P. desertorum Bunge	Rashol (2700)	58661	14	4x	Normal	100	2n = 14, 28
51.	P. gerardiana Lindl. ex Lehm. (=P. fragarioides auct. non L.)	Manikaran Sahib (2090) Nareng (2700)	57195 57164	28 28	8x 8x	Normal Cytomixis	86 79	2n = 14, 28, 56
52.	P. leuconata D. Don	Braagha (2600) Nareng (2700)	58357 58358	7 7	2x 2x	Normal Normal	95 94	First ever chromosome report for the species
53.	Spiraea canescens D. Don	Manikaran Sahib (2090)	58669	9	2x	Normal	100	2n = 18, 36
Family: Philadelphaceae
54.	Deutzia staminea R. Br. ex Wall.	Pulga (2100) Malana (2652) Gurthigarh (2660)	57210 57209 57208	13 13 13	2x 2x 2x	Multivalents Multivalents Normal	85 71 97	2n = 26
Family: Punicaceae
55.	Punica granatum L.	Shaat (1600)	56120	8	2x	Normal	85	2n = 14, 15, 16, 18, 19 2n = 16+0-3B 2n = 16+0-4B 2n = 16+07B
Family: Onagraceae
56.	Epilobium cylindricum D. Don	Malana (2652)	58399	18	4x	Normal	100	2n = 36
57.	Oenothera rosea L’Her. ex Ait.	Shaat (1600) Jari (1624) Sarsari (1700) Manikaran Sahib (2090)	56105 56071 56106 56115	7 7 7 7	2x 2x 2x 2x	Normal Normal Normal Normal	97 95 96 81	2n = 14, 28
Family: Cucurbitaceae
58.	Herpetospermum pedunculosum (C.B.) Clarke (= H. caudigerum Wall.) (= Bryonia pedunculosa Ser. ex DC.)	Chauki (2500) Sheela Village (2650)	58343 58344	10 10	2x 2x	Normal Normal	100 100	First ever chromosome report for the genus
Family: Apiaceae
59.	Bupleurum falcatum L.	Sheela Village (2650)	58657	8	2x	Normal	100	2n = 16, 18, 19-27-34, 40
60.	B. hamiltonii Balakr.	Chhagna (1700)	57328	8	2x	Cytomixis	88	2n = 16
61.	Chaerophyllum acuminatum Lindl.	Malana (2652)	58353	11	2x	Normal	100	2n = 22
62.	Heracleum candicans Wall.	Braagha (2600)	58352	11	2x	Chromatin bridges	96	2n = 22
63.	Pimpinella acuminata (Edgew.) Clarke	Bhuntar (1100)	57327	10	2x	Normal	98	2n = 18, 20
64.	Torilis japonica (Houtt.) DC. (=Caucalis anthriscus Scop.)	Malana (2652)	58354	8	2x	Normal	100	2n = 16
Subclass Gamopetalae; Family: Caprifoliaceae
65.	Lonicera hypoleuca Decne. (=L. elliptica Royle)	Malana (2652)	58655	9	2x	Normal	100	First ever chromosome report for the species
66.	Viburnum mullaha Buch.-Ham. ex D. Don	Tosh (2400)	58656	9	2x	Normal	100	2n = 18
Family: Dipsacaceae
67.	Dipsacus inermis Wall. (=D. strictus D. Don)	Tosh (2400) Malana (2652) Satyam Tunnel (2750)	56350 56344 56350	9 9 9	2x 2x 2x	Normal Non-synchronous disjunction, chromatin bridges Normal	100 93 98	2n = 18
Family: Compositae
68.	Achillea millefolium L.	Shaarni (1750) Pulga (2100) Braagha (2600) Malana (2652) Nareng (2700)	56092 56119 57159 56119 57165	9 9 9 9 9	2x 2x 2x 2x 2x	Normal Normal Normal Non-synchronous disjunction Normal	99 100 98 95 100	2n = 18, 35, 36, 44, 54, 62-74 2n = 36+1B 2n = 36+0-2B, 54+0-3B 2n = 54, 54+B 2n = 81 ±5
69.	Arctium lappa L.	Malana (2652)	56091	18	2x	Late disjunction	89	2n = 32, 36
70.	Artemisia gmelinii Web. ex Stechm. var. vestita Wall. (= A. vestita Wall.)	Jari (1624) Barshani (2150) Braagha (2600)	58388 58390 58391	9 9 9	2x 2x 2x	Normal Normal Normal	97 98 100	2n = 18, 36, 54
71.	A. indica Willd. (=A. vulgaris L.) (=A. dubia ex Press. var. dubia Wall.)	Manikaran Sahib (2090) Chauki (2500) Braagha (2600) Nareng (2700) Rashol (2700)	57644 58642 57207 57186 57230	18 18 18 18 18	4x 4x 4x 4x 4x	Late disjunction, laggards, chromatin bridges and abnormal sporads Normal Normal Normal Normal	100 95 92 88 83	2n = 16 2n = 16, 18, 36, 40, 54
72.	A. maritima L.	Gurthigarh (2660) Rashol (2700)	58408 58647	9 9	2x 2x	Normal Normal	87 93	2n = 18, 36, 54
73.	A. parviflora Buch.-Ham. ex Roxb.	Pulga (2100) Barshani (2150) Tosh (2400)	51725 51723 51724	9 9 9	2x 2x 2x	Normal Multivalents Normal	99 81 86	2n = 18, 36
74.	A. roxburghiana Wall.	Tosh (2400) Malana (2652)	58670 58642	9 9	2x 2x	Normal Normal	90 100	2n = 18, 36
75.	A. scoparia Waldst. & Kit.	Manikaran Sahib (2090) Chauki (2500) Braagha (2600) Malana (2652) Gurthigarh (2660) Nareng (2700)	57204 57225 57226 57227 57228 57229	9 9 9 9 9 9	2x 2x 2x 2x 2x 2x	Normal Normal Normal Normal Normal Normal	100 100 97 98 100 100	2n = 16, 18, 36
76.	Aster penduncularis Wall. ex Nees (=A. asperulus (DC.) Hook.f.)	Pulga (2100) Tosh (2400) Malana (2652) Nareng (2700)	56093 56349 56093 56342	27 27 27 27	6x 6x 6x 6x	Normal Normal Normal Cytomixis	100 91 100 91	2n = 54
77.	Bidens pilosa L.	Sarsari (1700) Barshani (2100) Tosh (2400) Nareng (2700) Satyam Tunnel (2750)	56324 56323 56326 56327 56325	36 36 36 36 36	6x 6x 6x 6x 6x	Normal Normal Normal Normal Normal	100 100 100 95 98	2n = 24, 46, 48, 70, 72, 76, 96
78.	Blumea mollis (D. Don) Merr. (=B. neilgherrensis Hook.f.) (=B. weightiana DC.) (= Erigeron mollis D. Don)	Jari (1624)	58402	9	2x	Normal	93	2n = 18, 20, 22 2n = 18+1-2B
79.	Chrysanthemum leucanthemum L.	Malana Dam (1878) Satyam Tunnel (2750)	57188 57329	18 18	4x 4x	Multivalents, abnormal sporads Multivalents, chromatin bridges, laggards and abnormal sporads	64 71	2n = 18, 36, 54, 72 2n = 18, 54+1-3B
80.	Conyza stricta Willd.	Manikaran Sahib (2090) Nareng (2700) Rashol (2700) Satyam Tunnel (2750)	57198 57201 57199 57200	9 9 9 9	2x 2x 2x 2x	Normal Normal Normal Normal	83 100 90 95	2n = 18, 36 2n = 18+1B
81.	Cotula anthemoides L.	Jari (1624)	58413	20	4x	Normal	100	2n = 20, 36
82.	Crepis foetida L.	Jari (1624)	58400	5	2x	Cytomixis, Non-synchronous disjunction, out of plate bivalents,	92	2n = 10, 16, 20
83.	Erigeron annuus (L.) Pers.	Jari (1624) Pulga (2100) Tosh (2400) Sheela Village (2650)	56068 56069 56353 56352	2n = 27 2n = 27 2n = 27 2n = 27	3x 3x 3x 3x	Univalents, scattered distribution, laggards, abnormal sporads in all the accessions	74 81 82 80	2n = 18, 26, 27, 28, 54 2n = 18+0-9B
84.	E. canadensis L. (=Conyza canadensis (L.) Cronquist)	Jari (1624) Barshani (2150) Kasol (2614)	56348 56118 56048	27 27 27	6x 6x 6x	Normal Normal Normal	95 93 98	2n = 18, 36, 54
85.	Eupatorium adenophorum Spreng. (= E. glandulosum H.B. & K. Nov. Gen) (= Ageratina adenophora (Spreng.) King & H. Rob.)	Jari (1624) Shaarni (1750) Barshani (2150) Chauki (2500)	57324 57325 57326 57330	51 51 51 51	3x 3x 3x 3x	Abnormal, trivalents, univalents, irregular distribution, laggards and abnormal sporads in all the accessions	64 80 88 88	2n = 51
86.	Galinsoga parviflora Cav.	Sarsari (1700) Barshani (2150)	57231 57232	8 8	2x 2x	Normal Normal	99 100	2n = 16, 32, 48
87.	Gerbera lanuginosa (Wall. ex DC.) Benth. (=G. gossypina (Royle) Beauv.)	Manikaran Sahib (2090) Kasol (2614)	57189 57211	24 24	4x 4x	Precocious disjunction, inter-bivalent connections in both the accessions	92 98	2n = 18, 24, 46
88.	Gnaphalium affine D. Don	Jaan (1500) Sarsari (1700)	57170 57192	7 7	2x 2x	Normal Normal	100 100	2n = 14 2n = 14+1B
89.	Gynura cusimbua (D. Don.)Moore (= G. angulosa DC.)	Kheerganga (2960) Malana (2652) Rashol (2700)	57319 58389 58398	8 8 8	2x 2x 2x	Precocious disjunction in all the accessions	96 92 100	2n = 18, 20, 40
90.	Inula grandiflora Willd.	Nareng (2700) Chhagna (1700) Malana (2652)	58680 58681 58682	8 16 16	2x 4x 4x	Cytomixis Precocious disjunction Precocious disjunction	89 87 93	2n = 16
91.	Lactuca dissecta D. Don	Jari (1624) Kasol (2614)	57174 57177	8 8	2x 2x	Normal Normal	100 98	2n = 16
92.	L. dolichophylla Kitam (=L. longifolia DC.)	Chhagna (1700) Pulga (2100)	58362 58401	8 8	2x 2x	Cytomixis, laggards, chromatin bridges, tripolar distribution and sporads with micronuclei in both the accessions	83 91	2n = 16
93.	L. macrorhiza (Royle) Hook.f. (=Cicerbita macrorhiza (Royle) Beauv.)	Malana (2652)	58383	8	2x	Normal	100	2n = 16
94.	Myriactis nepalensis Less.	Malana (2652)	58649	18	2x	Normal	100	2n = 36
95.	M. wallichii Less.	Pulga (2100) Malana (2652) Rashol (2700) Nareng (2700)	57181 57183 57182 58359	18 18 18 18	2x 2x 2x 2x	Normal Normal Normal Normal	100 100 98 100	2n = 36
96.	Phagnalon niveum Edgew.	Jari (1624) Kasol (2614)	58351 58371	9 9	2x 2x	Normal Normal	100 100	2n = 18
97.	Prenanthes brunoniana Wall. ex DC.	Braagha (2600) Gurthigarh (2660) Kheerganga (2960)	56346 57184 58373	8 8 8	2x 2x 2x	Cytomixis Cytomixis Normal	93 85 100	2n = 16
98.	Rhyncospermum verticillatum Reinw.	Kasol (2614)	58378	9	2x	Normal	96	2n = 18
99.	Senecio chrysanthemoides DC. (=S. laetus Edgew.)	Pulga (2100) Tosh (2400) Malana (2652) Gurthigarh (2660)	57298 58367 57297 57299	20 20 20 20	4x 4x 4x 4x	Normal Normal Normal Normal	100 88 100 98	2n = 40
100.	S. graciliflorus DC.	Malana (2652) Kheerganga (2960) Chander-khani Pass (3650)	57317 57332 57318	20 20 20	4x 4x 4x	Normal Cytomixis Cytomixis	100 97 96	2n = 40
101.	S. pedunculatus Edgew.	Malana (2652) Rashol (2700)	58646 58645	20 20	4x 4x	Late disjunction and chromatin bridges in both the accessions	98 97	First ever chromosome report for the species
102.	S. rufinervis DC.	Sheela Village (2650) Rashol (2700) Nareng (2700) Satyam Tunnel (2750) Chander-khani Pass (3650)	57172 57930 57157 57158 57931	20 20 20 20 20	4x 4x 4x 4x 4x	Cytomixis Normal Normal Normal Normal	95 94 91 100 100	2n = 20, 36, 40
103.	Solidago canadensis L.	Sarsari (1700)	58650	18	4x	Normal	100	2n = 18, 36, 54 2n = 18+0-1B
104.	S. virgaurea L.	Jaan (1500) Sarsari (1700) Shaarni (1750) Malana (2652) Tosh (2400)	57176 57156 57167 57180 58370	9 9 9 9 9	2x 2x 2x 2x 2x	Normal Normal Normal Normal Normal	99 100 100 100 100	2n = 18
105.	Sonchus asper (L.) Hill	Pulga (2100) Barshani (2150)	58386 57296	9 9	2x 2x	Normal Normal	100 98	2n = 18, 32, 36 2n = 18+3B
106.	S. brachyotus DC. (=S. arvensis L.)	Jari (1624) Shaarni (1750)	57302 57306	9 9	2x 2x	Normal Normal	100 100	2n = 18, 36
107.	S. oleraceus L.	Jari (1624) Satyam Tunnel (2750)	57295 57294	16 16	4x 4x	Normal Normal	100 100	2n = 18, 20, 32, 36
108.	Taraxacum officinale Wigg.	Jari (1624) Chhingra (1750) Malana Dam (1878) Kasol (2614) Manikaran Sahib (2090) Tosh (2400) Malana (2652) Rashol (2700) Nareng (2700) Satyam Tunnel (2750)	56102 58034 56104 56055 56058 58033 56103 58032 56112 58031	8 8 8 8 2n = 24 2n = 24 2n = 24 2n = 24 16 16	2x 2x 2x 2x 3x 3x 3x 3x 4x 4x	Normal Normal Normal Normal Abnormal, trivalents, univalents, unequal distribution, dyads in all the accessions with 2n = 24 Chromatin bridges, laggards, dyads and polyads in both accessions	100 98 91 97 88 76 58 50 55 53	2n = 16, 18, 21-24, 26, 32, 34, 36, 37, 40, 48 2n = 24+1B 2n = 24+2B
109.	Tricholepis elongata DC.	Jaan (1500) Jari (1624) Sarsari (1700) Kasol (2614) Chander-khani Pass (3650)	57215 57216 57217 57214 58652	16 16 16 16 16	4x 4x 4x 4x 4x	Normal Normal Normal Normal Normal	100 97 98 100 100	2n = 32
110.	Tridax procumbens L.	Jari (1624) Pulga (2100)	58046 58039	18 18	4x 4x	Normal Normal	100 100	2n = 36
111.	Xanthium strumarium L. (=X. indicum L.)	Manikaran (2090) Kasol (2614)	57315 57316	18 18	2x 2x	Normal Normal	98 100	2n = 32, 36
112.	Youngia japonica (L.) DC. (=Crepis japonica (L.) Benth.) (= Prenanthes japonica L.)	Malana (2652) Rashol (2700)	58406 58400	8 8	2x 2x	Normal Normal	100 90	2n = 16, 18
Family: Campanulaceae
113.	Campanula ramulosa Wall.	Malana (2652)	58666	14	2x	Normal	100	2n = 24, 28
Family: Primulaceae
114.	Androsace lanuginosa Wall.	Malana (2652)	58668	10	2x	Cytomixis	91	First ever chromosome record for the species
115.	A. rotundifolia Hardw.	Gurthigarh (2660)	57331	10	2x	Cytomixis	89	2n = 20
Family: Gentianaceae
116.	Gentiana aprica (Decne.) (=G. decemfida var. aprica (Decne.) Clarke)	Jari (1624) Kasol (2614)	58393 58392	10 10	2x 2x	Normal Normal	100 100	2n = 20
117.	G. argentea (Royle ex D. Don) DC.	Shaat (1600) Jari (1624) Kasol (2614)	56116 56067 56087	9 9 9	2x 2x 2x	Normal Normal Normal	99 98 100	2n = 20
118.	Swertia alata (D. Don)Clarke	Malana (2652)	58671	12	2x	Normal	100	2n = 24, 26
119.	S. ciliata (G.Don) Burtt (=S. purpurascens Wall.)	Nareng (2700) Braagha (2600) Malana (2652) Nareng (2700)	56086 58356 58355 58678	9 13 13 13	2x 2x 2x 2x	Normal Normal Normal Normal	93 100 100 100	2n = 18, 20, 24, 26
Family: Boraginaceae
120.	Cynoglossum lanceolatum Forssk. (=C. micranthum Desf.)	Braagha (2600) Gurthigarh (2660) Satyam Tunnel (2750)	57179 57178 58350	12 12 12	2x 2x 2x	Cytomixis Normal Normal	90 84 97	2n = 24
121.	Trichodesma indicum (L.) R.Br. (=Borago indica L.) Morphovariant with pink flowers (MVI) Morphovariant with white flowers (MVII)	Chhingra (1750) Sheela Village (2650) Malana (2652) Gurthigarh (2660)	58364 58365 58365 58366	22 22 22 22	4x 4x 4x 4x	Abnormal Abnormal Normal Normal	75 80 83 79	2n = 22, 44
Family: Cuscutaceae
122.	Cuscuta reflexa Roxb.	Braagha (2600)	57163	16	4x	Normal	100	2n=28, 32, 36, 42, 48 2n = 28+0-2f, 30+0-2f, 32+2f 2n = 32+0-1f 2n = 32, 32+3f, 36+2f
Family: Solanaceae
123.	Datura stramonium L.	Manikaran Sahib (2090) Barshani (2150)	57162 57168	12 12	2x 2x	Normal Normal	96 98	2n = 24, 48
124.	Nicandra physalodes (L.) Gaertn. (=Atropa physalodes L.)	Jari (1624) Kasol (2614)	58405 58404	10 10	2x 2x	Normal Normal	96 100	2n = 19, 20, 21, 22 2n = 20+1B
125.	Solanum nigrum L.	Pulga (2100) Chauki (2500) Nareng (2700) Jari (1624) Tosh (2400) Kasol (2614) Chander-khani Pass (3650)	56359 56361 56360 56072 56355 56098 58377	12 12 12 24 24 24 24	2x 2x 2x 4x 4x 4x 4x	Normal Normal Normal Normal Normal Normal Normal	100 99 100 98 100 100 93	2n = 24, 36, 40, 48, 72, 94, 144
126.	S. pseudo-capsicum L.	Jari (1624)	56109	12	2x	Normal	100	2n = 24
127.	S. verbascifolium L. (=S. erianthum D. Don)	Malana (2652)	58349	12	2x	Normal	91	2n = 24, 36
128.	S. viarum Dunal	Tosh (2400) Malana (2652)	56080 56354	12 12	2x 2x	Normal Cytomixis	100 100	2n = 24 2n = 24+0-2B
129.	Withania somnifera (L.) Dunal	Shaat (1600) Jari (1624) Sarsari (1700)	56357 56077 56356	24 24 24	4x 4x 4x	Normal Normal Cytomixis	95 90 96	2n = 24, 48, 72
Family: Scrophulariaceae
130.	Leptorhabdos parviflora (Benth.) Benth. (=Gerardia parviflora Benth.)	Braagha (2600)	58379	7	2x	Normal	100	2n = 14
131.	Mazus japonicus (Thunb.) Kuntze (=M. pumilus (Burm.f.)	Chauki (2500)	58030	20	4x	Normal	100	2n = 38, 40, 52
132.	Pedicularis hoffmeisteri Klotz. (= P. megalantha D. Don)	Tosh (2400) Malana (2652)	58672 58665	8 8	2x 2x	Cytomixis Cytomixis	95 89	2n = 16, 32
133.	P. pectinata Wall. ex Benth.	Malana (2652) Barshani (2150)	57320 57321	8 8	2x 2x	Cytomixis Cytomixis	95 89	2n = 16
134.	Scrophularia himalensis Royle	Pulga (2100) Malana (2652)	56347 56362	24 24	4x 4x	Normal Normal	100 100	2n = 20, 48 2n = 48+2-4B
135.	Verbascum thapsus L.	Kheerganga (2960)	58412	18	2x	Normal	98	2n = 30, 34, 36, 48 2n = 34 + 0-2B
136.	Wulfenia amherstiana Wall.	Malana (2652) Satyam Tunnel (2750)	58396 58397	8 8	2x 2x	Normal Normal	96 94	2n = 16
Family: Bignoniaceae
137.	Incarvillea arguta Royle (=Amphicome arguta Lindl.)	Manikaran Sahib (2090) Tosh (2400) Chauki (2500)	58360 58348 58347	11 11 11	2x 2x 2x	Normal Normal Normal	91 100 92	2n = 22
Family: Acanthaceae
138.	Strobilanthes alatus Wall. ex Nees	Pulga (2100) Rashol (2700)	58659 58674	16 16	4x 4x	Normal Normal	100 100	2n = 32
Family: Verbenaceae
139.	Verbena officinalis L.	Sarsari (1700) Shaarni (1750)	56331 56332	7 7	2x 2x	Normal Normal	100 100	2n = 10, 12, 14
Family: Lamiaceae
140.	Ajuga parviflora Benth.	Jari (1624) Kasol (2614)	57166 56089	16 16	4x 4x	Normal Normal	100 97	2n = 32, 64 2n = 32+0-2B 2n = 64+0-2B
141.	Lamium album L.	Tosh (2400) Braagha (2600) Malana (2652) Nareng (2700) Satyam Tunnel (2750)	56088 56358 57190 57212 57213	9 9 9 9 9	2x 2x 2x 2x 2x	Normal Normal Cytomixis Cytomixis Cytomixis	89 93 81 90 80	2n = 16, 18
142.	Leucas lanata Benth.	Jaan (1500) Shaat (1600) Jari (1624) Chauki (2500)	56097 56391 56076 56345	15 15 15 15	2x 2x 2x 2x	Normal Normal Normal Normal	95 100 94 97	2n = 14, 22, 24, 30
143.	Melissa axillaris (Benth.) Bakh.f. (=M. parviflora Benth.)	Chauki (2500) Nareng (2700)	58407 58414	17 17	2x 2x	Normal Normal	100 100	2n = 32, 34
144.	Nepeta floccosa Benth.	Manikaran Sahib (2090)	58664	18	4x	Normal	91	2n = 18
145.	N. laevigata (D. Don) Hand.-Mazz. (=N. spicata Benth.) (= Betonica laevigata D. Don.)	Jari (1624) Kasol (2614)	58043 58042	9 9	2x 2x	Normal Normal	96 100	2n = 18, 36
146.	Origanum vulgare L.	Jaan (1500) Chaung (1700) Barshani (2150)	58027 58029 58028	15 15 15	2x 2x 2x	Normal Normal Normal	80 91 88	2n = 28, 30, 32
147.	Plectranthus coetsa Buch.-Ham. ex D. Don (=P. japonicus (Burm.f.) Koidz.)	Barshani (2150) Chauki (2500) Sheela Village (2650) Braagha (2600) Gurthigarh (2660)	57933 57935 57932 57936 57934	12 12 12 12 12	2x 2x 2x 2x 2x	Normal Normal Cytomixis Cytomixis Normal	100 100 87 97 91	2n = 22, 24
148.	P. rugosus Wall.	Bhuntar (1100) Chhagna (1700) Manikaran Sahib (2090) Rashol (2700)	57220 57221 57218 57219	12 12 12 12	2x 2x 2x 2x	Normal Normal Normal Normal	96 94 91 94	2n = 24
149.	Roylea cinerea (D. Don) Baill. (=R. elegans Wall.) (=R. calycina (Roxb.) Briq.)	Sarsari (1700)	58394	10	2x	Normal	93	2n = 34
150.	Salvia lanata Roxb.	Kasol (2614)	58651	10	2x	Normal	100	2n = 22, 24
151.	S. nubicola Wall. ex Sweet (=S. glutinosa auct. non. L.)	Pulga (2100) Tosh (2400) Chauki (2500) Satyam Tunnel (2750) Chander- khani Pass (3650)	57191 57185 57193 57194 57322	8 8 8 8 8	2x 2x 2x 2x 2x	Normal Normal Normal Normal Cytomixis	92 100 89 98 91	2n = 16 2n = 16+2B
152.	Thymus Linearis Benth. (=T. serpyllum L.)	Pulga (2100) Malana (2652) Kheerganga (2960)	57196 56341 56340	13 13 13	2x 2x 2x	Normal Normal Cytomixis	100 98 93	2n = 24, 26
Family: Plantaginace
153.	Plantago depressa Willd. (=P. tibetica Hook.f. & Thoms.)	Barshani (2150) Malana (2652) Satyam Tunnel (2750)	56082 57171 56084	6 6 6	2x 2x 2x	Normal Cytomixis Cytomixis	96 85 91	2n = 12, 24, 36 2n = 24+0-1 B
154.	P. lanceolata L.	Jari (1624) Braagha (2600) Kasol (2614)	52987 58026 52986	6 6 6	2x 2x 2x	Cytomixis Normal Normal	83 100 95	2n = 12, 13, 14, 24, 96 2n = 12+1B
155.	P. major L. (=P. rugelli Decne.) Morphovariant with long spikes (MVI) Morphovariant with short spikes (MVII)	Jari (1624) Tosh (2400) Manikaran Sahib (2090) Chauki (2500)	58040 58595 58041 58596	6 6 6 6	2x 2x 2x 2x	Normal Normal Normal Normal	100 91 100 100	2n = 12, 16, 18, 24, 22-24, 23+f
Subclass Monochlamydeae; Family: Chenopodiaceae
156.	Chenopodium album L.	Sheela Village (2650) Nareng (2700)	58675 58676	27 27	6x 6x	Normal Normal	100 100	2n = 18, 36, 54
Family: Polygonaceae
157.	Bilderdykia pterocarpa (Wall. ex Meisn.) Greene (=Polygonum pterocarpum Wall. ex Meisn.	Jari (1624)	58367	40	8x	Normal	100	First chromosome report for the species
158.	Fagopyrum dibotrys (D. Don) Hara (=F. cymosum Meissn.)	Barshani (2150)	58662	8	2x	Multivalents	89	2n = 16, 24, 32
159.	Rumex hastatus D. Don	Jari (1624) Kasol (2614)	56065 56066	9 9	2x 2x	Normal Normal	100 100	2n = 12, 18
160.	R. nepalensis Spreng.	Manikaran Sahib (2090) Barshani (2150) Chauki (2500) Malana (2652)	56057 56056 58382 58387	40 40 60 60	8x 8x 12x 12x	Normal Normal Normal Normal	90 91 94 93	2n = 54, 120
Family: Euphorbiaceae
161.	Andrachne cordifolia (Decne.) Müell. Arg.	Kasol (2614) Malana (2652)	57169 57173	12 12	2x 2x	Normal Normal	100 100	2n = 22, 24
162.	Emblica officinalis Gaertn. (=Phyllanthus emblica L.)	Bhuntar (1100)	57187	52	8x	Normal	100	2n = 26, 28, 52, 98, 104, 196
Family: Buxaceae
163.	Sarcococca pruniformis Lindl. (=S. saligna (D. Don) Müell-Arg.)	Pulga (2100) Kasol (2614)	56117 56079	14 14	2x 2x	Normal Normal	100 98	2n = 28
Family: Cannabaceae
164.	Cannabis sativa L.	Tosh (2400) Malana (2652)	57929 57928	10 10	2x 2x	Normal Normal	100 100	2n = 20, 40, 80

* PUN is the abbreviation used in “Index Herbarium” by Holmgren and Holmgren (1998).

**Previous reports on chromosome numbers reference are from Darlington and Wylie (1955), Bolkovskikh et al. (1969), Löve and Löve (1975), Fedorov (1969), Moore (1970, 1971, 1972, 1973, 1974, 1977), Goldblatt (1981, 1984, 1985, 1987), Goldblatt and Johnson (1990, 1991, 1994, 1996, 1998, 2000, 2003, 2006), Kumar and Subramanian (1986), Khatoon and Ali (1993), IOPB Chromosome Number Reports published in Taxon and Index to Plant Chromosome Numbers (http://mobot.mobot.org/W3T/Search/ipcn.html).

Table 2. Comparison of macro- and microscopic characters in the two cytotypes of Inula grandiflora.

		Cytotypes
	Characters/site of collection	Diploid (n = 8) (mean± SD)*	Tetraploid (n = 16) (mean± SD)*
1.	Site of collection	Nareng Village (2700 m)	Chaagna Village (1700 m), Malana Village (2652 m)
2.	Distribution	Less common	More common
3.	Habit	Perennial herb	Perennial herb
4.	Habitat	Open moist slopes	Open rocky slopes
5.	Plant height (cm)	50–90 (72.66 ± 14.58)	60–100 (82.2 ± 15.73)
6.	Leaves
	(i) Number of leaves/plant	12–15 (13.92 ± 1.20)	8–22 (16.58 ± 5.44)
	(ii) Texture	Thick	Relatively less thick
	(iii) Shape	Elliptic to oblong	Sub cordate to elliptic oblong
	(iv) Size (cm)
	Length	12.20–14.78 (13.59 ± 1.06)	16.12–18.50 (17.31 ± 0.93)
	Breadth	1.14–3.12 (2.27 ± 0.79)	2.27–4.78 (3.30 ± 0.77)
7.	Capitula
	(i) Color	Orange-yellow	Orange-yellow
	(ii) Size (cm)	6–10 (9.16 ± 0.77)	8–12 (9.6 ± 1.59)
8.	Stomatal size (µm)
	Length	16.28–18.85 (17.47 ± 1.02)	60.32–63.00 (61.72 ± 1.08)
	Breadth	8.39–11.67 (10.11 ± 1.31)	18.59–22.23 (20.18 ± 1.34)
9.	Pollen size (µm)
	Length	20.12–20.63 (20.43 ± 0.20)	21.20–26.40 (23.61 ± 2.03)
	Breadth	17.08–17.54 (17.29 ± 0.17)	17.35–25.63 (20.91 ± 3.34)
10.	Pollen fertility (%)	80–89 (84.83 ± 3.70)	87–93 (90.20 ± 2.47)

*Mean value (mean) and standard deviation (SD) of quantitative characters have been calculated statistically in both the cytotypes and it is found to be significantly different among populations.

Impatiens thomsonii, a widely distributed species in Northwest Himalayas, has been investigated chromosomally by several cytologists. As per the previous reports of 2n = 12 (Sharma and Ghosh 1976), 2n = 14 (Koul and Gohil 1973), 2n = 16 (Sharma and Ghosh 1976) and 2n = 20 (Khoshoo 1955, 1966), the species depicts considerable chromosomal variability involving dysploidy (2n = 12, 14, 16, 20). The presently analyzed accession from the area adds a new chromosome count of 2n = 18.

Lepidium sativum L., seeds, which are used by locals for curing indigestion and constipation, showed a tetraploid chromosome count of n = 16 (Figure 1(t)), compared to the earlier diploid reports of 2n = 16 by workers from outside of India (Jaretzky 1929; Reese 1950, 1952; Lan and Cheo 1989). The species is also known to have intraspecific 2x (2n = 12) and 4x (2n = 24) cytotypes based on x = 6 (Fedorov 1969).

The presently analyzed wild accession of Lespedeza juncea showed a variable diploid chromosome count of 2n = 22 against the earlier reports of 2n = 18 by Cooper (1936), Pierce (1939) from outside of India and 2n = 20 by Pierce (1939), Sokolovskaya et al. (1989) from outside of India and by Kumar and Singhal (2011) from Lahaul-Spiti region of Northwest Himalayas in India.

Nepeta floccosa Benth., which has been counted chromosomally for the first time from India, adds a tetraploid gametic chromosome count of n = 18 (based on n = 9) against the earlier diploid record of n = 9 reported by Khatoon and Ali (1993) from Pakistan.

The gametic chromosome count in Potentilla desertorum Bunge (n = 14, Figure 1(u)) from the valley adds a new tetraploid cytotype (based on x = 7) against the earlier report of diploid cytotype (n = 7) by Rani et al. (2012) from Kangra district, Himachal Pradesh.

The studied accession of Roylea cinerea with a gametic chromosome count of n = 10 (Figure 1(v)) adds a new intraspecific diploid cytotype against the earlier recorded polyploid cytotype of 2n = 34 by Mehra and Gill (1968), Gill (1970), and Saggoo and Bir (1983) from other regions of Himalayas in India.

Rumex nepalensis Spreng., a highly polymorphic species, is distributed in a wide range of habitats in Northwest Himalayas. The present study based on four accessions revealed the existence of intraspecific 8x (n = 40, Figure 1(w)) and 12x (n = 60, Figure 1(x)) cytotypes based on x = 10. The individuals of the 12x cytotype grow much taller than those of 8x. We here report for the first time the existence of the 8x cytotype, while the 12x cytotype has already been reported by Mehra and Dhawan (1966) from other region of Northwest Himalayas in India.

The wild accessions of Salvia lanata Roxb. analyzed meiotically showed a diploid chromosome number of 2n = 20 against the already reported chromosome counts of 2n = 22 (Mehra and Gill 1968; Gill 1971, 1984; Sarkar et al. 1975) and 2n = 24 (Saggoo and Bir 1983) from other parts of India. This thus indicates that Indian taxa of the species depict the existence of intraspecific dysploid cytotypes at diploid level (2n = 20, 22, 24).

3.2. Meiotic behavior

Of the 173 taxa analyzed for male meiotic course, meiocytes in 72 taxa showed various abnormalities which included multiple associations of chromosomes in diploids (Artemisia parviflora Buch.-Ham. ex Roxb., n = 9; Deutzia staminea R.Br. ex Wall., n = 13; Fagopyrum acutatum (D. Don) Hara, n = 8), multivalents and univalents in polyploids (Erigeron annuus (L.) Pers., 2n = 3x = 27; Eupatorium adenophorum Spreng, 2n = 3x = 51; Taraxacum officinale Wigg., 2n = 3x = 24; Chrysanthemum leucanthemum L., 2n = 36; Trichodesma indicum (L.) R. Br., 2n = 4x = 44); a phenomenon of cytomixis involving chromatin transfer (35 species), chromatin stickiness resulting in delayed segregation of chromosomes and laggards in Androsace lanuginosa (n = 10), A. rotundifolia Hardw., (n = 10), Artemisia maritima L., (n = 9), Astragalus chlorostachys Lindl., (n = 8), Bupleurum hamiltonii Balakr. (n = 8), Clematis connata DC. (n = 8), C grata Wall. (n = 8), Conyza stricta Willd. (n = 9), Deutzia staminea (n = 13), Impatiens amphorata Edgew. (n = 7), Pedicularis hoffmeisteri Klotz. (n = 8), P. pectinata Wall. ex Benth. (n = 8), Plantago depressa Willd. (n = 6), P. lanceolata L. (n = 6), Ranunculus laetus Wall. (n = 14), Salvia nubicola Wall. ex Sweet (n = 8), Senecio graciliflorus DC. (n = 20), and Solanum verbascifolium L. (n = 12). In some cases, due to severe stickiness in chromatin material, chromosomes even failed to separate during anaphases/telophases, resulting in the formation of restitution nuclei and abnormal sporads such as monads and dyads and consequently pollen grains of variable sizes. Singhal and Kumar (2008) and recently Kumar et al. (2016) in Meconpsis aculeata Royle and Dewitte et al. (2010) in Begonia have suggested that chromatin stickiness has played an important role in nuclear restitution and ultimately failure of cytokinesis.

Other meiotic irregularities which have been noticed in the meiocytes in the plants of the valley included non-synchronous (early and late) disjunction of bivalents (39 species) inter-bivalent/inter-chromosomal connections, impaired synapsis (I. scabrida DC.), syncyte meiocytes resulting due to whole migration of chromatin during cytomixis and cell fusion (Ranunculus laetus), abnormal spindle activity (Chrysanthemum leucanthemum, Plectranthus coetsa Buch.-Ham. ex D. Don, Potentilla gerardiana Lindl. ex Lehm., Taraxacum officinale, Withania somnifera (L.) Dunal) and meiocytes with supernumerary nucleoli (Aconitum heterophyllum Wall., Clematis connata DC., Impatiens scabrida, Plantago lanceolata L., Potentilla gerardiana, Trichodesma indicum).

3.3. Intraspecific euploid and dysploid cytotypes

Intensive accession based analysis from the valley added new euploid cytotypes at world level in nine species, Lepidium sativum (n = 16, 4x), Potentilla desertorum (n = 14, 4x), Cotula anthemoides L. (n = 20, 4x), Gerbera lanuginosa (n = 24, 4x), Inula grandiflora (n = 16, 4x), Solidago canadensis L. (n = 18, 4x), Nepeta floccossa (n = 18, 4x) Roylea cinerea (n = 10, 2x), and Rumex nepalensis (n = 40, 8x). Such intraspecific diploid/polyploid cytotypes are recorded for the first time in Indian taxa of Fagopyrum dibotrys (n = 8, 2x), Phagnalon niveum (n = 9, 2x), Potentilla desertorum (n = 14, 4x) and Solidago canadensis (n = 18, 4x).

Additional dysploid chromosome numbers have also been reported in nine species, Corydalis thyrsiflora (2n = 14, 16), Geranium lucidum (2n = 20, 28, 40, 42, 60), Impatiens thomsonii (2n = 12, 14, 16, 18, 20), Gentiana argentea (2n = 18, 20), Gerbera lanuginosa (2n = 46, 48) Gynura cusimbua (2n = 16, 18, 20), Lespedeza juncea (2n = 18, 20, 22), Roylea cinerea (2n = 20, 34) and Salvia lanata (2n = 20, 22, 24). The dysploid cytotypes have also been recorded in the analyzed accessions of Impatiens amphorata (2n = 14, 18) and Swertia ciliata (2n = 18, 26) from the valley. Also, intraspecific euploid cytotypes are recorded in six species analyzed from different localities of the valley, Silene vulgaris L. (2x, 4x), Agrimonia eupatoria L. (4x, 6x), Inula grandiflora (2x, 4x), Taraxacum officinale (2x, 3x, 4x), Solanum nigrum L. (2x, 4x) and Rumex nepalensis (8x, 12x). Among these, the 4x cytotype in Inula grandiflora (2n = 32) and 8x cytotype in Rumex nepalensis (2n = 80) are the first records on a worldwide basis.

3.4. Pollen fertility

On the basis of stainability tests, it has been noticed that a large number of taxa showed a varying amount of pollen sterility (Table 1). Pollen grains of heterogeneous sizes have also been noticed in some taxa. In majority of the cases, pollen malformation is attributed to the consequence of meiotic irregularities.

3.5. Multivalents in diploids

Multiple associations of chromosomes (ring or chain type) reported in the wild accessions of Deutzia staminea (2n = 26; Figure 2(a)), Artemisia parviflora (2n = 18) and Fagopyrum dibotrys (2n = 16; Figure 2(b)) seem to be the result of structural heterozygosity for reciprocal translocations. Varying amount of pollen sterility in such structural heterozygotes has resulted as a consequence of adjacent type orientation of multivalents during M-I as suggested earlier (Burnham 1956; Sharma and Gohil 2003; Ghaffari et al. 2009; Gupta et al. 2010; Talukdar 2010; Rana et al. 2012; Kumar and Singhal 2013; Singhal et al. 2014, 2016; Kumar et al. 2015).

3.6. Imbalanced polyploids

Of the 64 polyploid taxa covered presently, imbalanced polyploids were detected in Erigeron annuus (2n = 3x = 27), Eupatorium adenophorum (2n = 3x = 51) and Taraxacum officinale (2n = 3x = 24). Meiosis in these triploid taxa was characterized by the high frequency of univalents (Figure 2(c)), scattered and unequal distribution of chromosomes during anaphases, abnormal sporads and high frequency of sterile pollen grains. Owing to good amount of viable seed production through apomixis, these polyploids seem to have established well in the Himalayas. The tetraploid taxa of Chrysanthemum leucanthemum (2n = 36) and Trichodesma indicum (2n = 44) showed the presence of some multivalents besides bivalents. In the remaining polyploid taxa, the meiocytes depicted complete bivalent formation which might indicates to their allopolyploid nature.

3.7. Cytomixis and associated meiotic irregularities

Cytomixis involving chromatin transfer among proximate meiocytes has been observed in 35 species (Figure 2(d), 2(e)), i.e. Andrachne cordifolia (Decne) Müell. Arg. (n = 12), Androsace lanuginosa (n = 10), A. rotundifolia (n = 10), Anemone rivularis Buch.-Ham. ex DC. (n = 8), Artemisia maritima (n = 9), Aster peduncularis Wall. ex Nees (n = 27), Astragalus graveolens Benth. (n = 8), Bupleurum hamiltonii (n = 8), Clematis connata DC. (n = 8), C. grata (n = 8), Crepis foetida (n = 5), Cynoglossum lanceolatum Forssk. (n = 12), Delphinium pyramidale (n = 8), Deutzia staminea (n = 13), Erigeron annuus (2n = 27), Inula grandiflora (n = 8), Lactuca dolicophylla Kitam. (n = 8), Lamium album L. (n = 9), Lotus corniculatus L. (n = 6), Pedicularis hoffemeistri (n = 8), P. pectinata (n = 8), Plantago depressa (n = 6), P. lanceolata (n = 6), Plectranthus coetsa (n = 12), Potentilla argyrophylla Wall. ex Lehm. (n = 14), P. gerardiana (n = 42), Prenanthes brunoniana Wall. ex DC. (n = 8), Ranunculus hirtellus Royle (n = 16), R. laetus (n = 14), Salvia nubicola (n = 8), Senecio graciliflorous (n = 20), S. rufinervis DC. (n = 20), Solanum viarum Dunal (n = 12), Thymus linearis Benth. (n = 13), and Trifolium repens L. (n = 16).

The chromatin migration during cytomixis is either partial or complete, resulting in hypoploid, hyperploid or enucleated meiocytes. The products of such meiocytes led to the formation of pollen grains/male gametes with variable genetic constitution and sterile pollen grains. Meiocytes depicting chromatin transfer also showed pycnotic chromatin material, extra chromatin masses, agglutinated chromatin, inter-bivalent/inter-chromosomal connections, abnormal spindle activity, abnormal sporads (Figure 2(g), 2(h)) and laggards and chromatin bridges. The products of such aberrant meiocytes resulted in considerable amounts of pollen sterility and pollen grains of variable sizes (Figure 2(i)). Similar effects of cytomixis in inducing meiotic irregularities and pollen malformation have been reported in Chlorophytum comosum (Lattoo et al. 2006), Meconopsis aculeata (Singhal and Kumar 2008), Hippophae rhamnoides (Singhal et al. 2008), Salvia miltiorrhiza (Song and Li 2009), Artemisia absinthium (Malik et al. 2010), Clematis orientalis (Kumar et al. 2010), Plantago lanceolata (Himshikha et al. 2010), Nicotiana tabacum (Mursalimov and Deineko 2011), Ranunculus laetus (Kumar et al. 2011), Thalictrum foetidum (Singhal et al. 2011), Dianthus angulatus (Kumar et al. 2012), Houttuynia cordata (Guan et al. 2012), Pinellia ternata (Liu et al. 2012), Nepeta govaniana (Kaur and Singhal 2014), Ophrys lutea (Feijo and Paris 1989), Silene vulgaris (Kumar et al. 2014b) and Anemone rivularis (Kumar et al. 2015). Bedi (1990) had also reported that cytomixis is mainly responsible for the reduced fertility of gametes in several forest tree species.

3.8. Chromosomal evolution

The present study also suggests that plants of this phytogeographically isolated valley with ecologically disturbed habitats are quite active in evolution, as heterogeneity in chromosome numbers is shown, involving polyploidy and aneuploidy.

3.8.1. Polyploidy

Perusal of the existing literature reveals that as many as 41 cytologically investigated species (25%) exist at different ploidy levels with the highest level of 12x (Rumex nepalensis). The role of polyploidy becomes more evident as 64 out of the 164 presently analyzed species possess intraspecific euploid cytotypes. The number of such species with intraspecific cytotypes is likely to increase when more data become available from other unexplored and isolated regions, particularly the higher hills of the valley. This is apparent from the first ever reports of diploid/polyploid cytotypes recorded presently in Lepidium sativum (n = 16, 4x), Potentilla desertorum (n = 14, 4x), Gerbera lanuginosa (n = 24, 4x), Inula grandiflora (n = 16, 4x), Solidago canadensis (n = 18, 4x), Nepeta floccossa (n = 18, 4x) Roylea cinerea (n = 10, 2x), and Rumex nepalensis (n = 40, 8x). Gustafasson (1948), Schranz et al. (2005) and Lo et al. (2009) opined that vegetative and apomictic modes of reproduction and polyploidy are two important processes of evolution which are closely associated with each other. Taxa having high incidence of polyploidy often reproduce vegetatively or are apomicts. Vegetative modes of propagation, which have been considered as a pre-condition for polyploidy (Lewis and John 1963), have been observed presently in polyploid taxa of Agrimonia eupatoria (4x, 6x), Erigeron annuus (3x) and Taraxacum officinale (3x, 4x).

3.8.2. Aneuploidy

Aneuploidy, which causes chromosomal variation in the plants of the valley, is equally significant as is evident from the existence of dysploid cytotypes in 71 species at diploid and/or polyploid levels (see Table 1). The role of aneuploidy in evolution is also evident from the existence of several dibasic and polybasic genera which seem to have originated via increase or decrease in chromosome numbers through aneuploidy, as suggested by a number of workers (Raven and Kyhos 1965; Stebbins 1966; Khosla 1975; Kaur et al. 2014; Rani et al. 2014).

3.8.3. Dibasic

Andrachne L. (x = 11, 12), Androsace L. (x = 9, 10), Anemone L. (x = 7, 8), Boenninghausenia Rehb. ex Meisn. (x = 9, 10), Chenopodium L. (x = 8, 9), Emblica L. (x = 7, 13), Heracleum L. (x = 10, 11), Lathyrus L. (x = 6, 7), Melissa L. (x = 16, 17), Ranunculus L. (x = 7, 8), Tridax L. (x = 9, 10), Trifolium L. (x = 7, 8), Wulfenia Jacq. (x = 8, 9) and Youngia Cass. (x = 8, 9).

3.8.4. Polybasic

Blumea DC. (x = 8, 9, 10, 11), Corydalis DC. (x = 5, 6, 7, 8), Filipendula Mill. (x = 7, 8, 9), Gnaphalium L. (x = 7, 8, 9), Lepidium L. (x = 6, 7, 8), Lespedeza Michx. (x = 9, 10, 11), Lotus L. (x = 5, 6, 7), Pimpinella L. (x = 8, 9, 10, 11), Silene L. (x = 9, 10, 11, 12, 13, 14), Stellaria L. (x = 9, 10, 11, 12, 13, 14), Sonchus L. (x = 7, 8, 9, 10), Swertia L. (x = 7, 8, 9, 10, 11, 12, 13), Thalictrum L. (x = 6, 7, 8), Verbena L. (x = 5, 6, 7), Vicia L. (x = 5, 6, 7), and Zanthoxyllum L. (x = 16, 17, 18) are the genera where the base numbers are present in regular dysploid series. Such base numbers seems to have originated through dysploid increase or decrease in chromosome numbers.

In the remaining genera, i.e. Aconitum L. (x = 8, 10, 12, 13, 17), Ajuga L. (x = 8, 14, 15), Artemisia L. (x = 7, 8, 9, 10, 17), Aster L. (x = 4, 5, 7, 8, 9, 13), Astragalus L. (x = 6, 7, 8, 11, 12, 13), Bidens L. (x = 10, 11, 12, 18), Bupleurum L. (x = 4, 6, 7, 8, 11), Campanula L. (x = 7, 8, 10, 12, 14, 17), Chaerophyllum Lindl. (x = 6, 7, 11), Cotula L. (x = 9, 10, 13), Crepis L. (x = 3, 4, 5, 6, 7, 8, 11), Epilobium L. (x = 9, 10, 12, 13, 16), Eupatorium L. (x = 10, 17), Gentiana L. (x = 5, 6, 7, 8, 9, 10, 12, 13, 19), Gerbera L. (x = 9, 12, 23, 25), Geranium L. (x = 9, 10, 11, 12, 13, 14, 15, 16, 17, 23), Gynura Cass. (x = 5, 8, 9, 10, 17), Hypericum L. (x = 7, 8, 9, 10, 12), Impatiens L. (x = 3, 4, 5, 6, 7, 8, 9, 10, 12, 13), Lactuca L. (x = 5, 8, 9, 17), Leucas R.Br.(x = 8, 9, 11, 13, 14, 15), Mazus Lour. (x = 8, 10, 19), Nepeta L. (x = 7, 8, 9, 13, 17), Plantago L. (x = 4, 5, 6, 7, 9), Plectranthus L’ Hér. (x = 7, 11, 12, 13, 15, 17), Roylea Wall. ex Benth. (x = 10, 17), Salvia L. (x = 6, 7, 8, 9, 10, 11, 13), Scrophularia L. (x = 9, 10, 12, 13, 29), Senecio L. (x = 5, 9, 10, 11, 12, 13, 14, 16, 19, 23), Spiraea L. (x = 5, 7, 8, 9, 17), Strobilanthes Blume (x = 7, 8, 9, 10, 11, 13, 14, 15, 16, 21), Thlaspi L. (x = 7, 9, 12, 13), Torilis Adans. (x = 6, 8, 11), Trichodesma R.Br. (x = 7, 10, 11, 12), Trigonella L. (x = 7, 8, 9, 11), Thymus L. (x = 12, 13, 14, 15, 27, 29), Verbascum L. (x = 12, 13, 14, 15, 16, 17, 18, 22, 23), Viola L. (x = 5, 6, 7, 8, 9, 11, 13, 17) and Youngia Cass. (x = 5, 8, 10). The dibasic and polybasic nature might have originated through polyploidy followed by aneuploidy or dibasic polyploidy.

Aneuploidy is often correlated in flowering plants with the asexual mode of reproduction. Nassar (2003) on the basis of cytological and embryological studies in the apomictic clones of cassava (Manihot esculenta) correlated the occurrence of apomixis with aneuploidy. Levin (2002) also discussed the role of aneuploidy with asexual mode of reproduction. Anemone rivularis, Delphinium pyramidale, Lotus corniculatus, Potentilla argyrophylla, Ranunculus hirtellus, R. laetus, Trifolium pratense and T. repens, where aneuploid chromosomal variations are quite common, are observed to reproduce vegetatively through rhizomes and stolons. As such, aneuploidy seems to have played a fairly active role in the evolution of these species.

The meiotic abnormalities in the presently analyzed species from the valley have affected the genetic constitution and viability of male gametes. The viable gametes with variable genetic constitution have resulted in the origin of aneuploids, polyploids and species complexes. Non-viable gametes, resulting due to meiotic disturbances, might have been responsible for reduced reproductive success in several species through seeds. Consequently, the plants have adopted alternate means of propagation through vegetative modes, which are quite common in the plants of the valley.

Acknowledgments

The authors are grateful to the head, Department of Botany, Punjabi University, Patiala and Dr P. Singh, Director, Botanical Survey of India, Headquarters Kolkata and Head of- Office, NRC, Dehra Dun, for the necessary herbarium (PUN, BSD) and library facilities.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors are indebted to the University Grants Commission (UGC), New Delhi, for providing financial support [DRS SAP I, II & III], ASIST programme, DBT-IPLS (Department of Biotechnology Interdisciplinary Programme of Life Sciences for advanced research and education) Project funded by the Department of Biotechnology, Governmentof India and Senior Research Fellowship to Rohit Kumarunder Rajiv Gandhi National Fellowship [F1-17.1/2012-13/RGNF-2012-13-SC-HIM-18573].