Savita Rani

Cytology of five species of subfamily Papaveroideae from the Western Himalayas

During the present course, population-based meiotic studies were carried out on five species of subfamily Papaveroideae from selected localities of Kashmir and Himachal Pradesh in the Western Himalayas (India). Varied intraspecific chromosome counts were reported for the first time in Argemone mexicana and Meconopsis latifolia, both existing on 2n = 2x = 14. The x = 7, confirmed for the first time from the newly found diploid cytotype, is suggested to be the primary chromosomal basic number for the Meconopsis. Furthermore, meiotic course was noted to be normal in Argemone ochroleuca, it varied from normal to abnormal in the populations of A. mexicana and Papaver dubium whereas it was invariably found to be abnormal in all the populations of Meconopsis aculeata and M. latifolia. These anomalous taxa were marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges resulting in abnormal microsporogenesis, and production of heterogeneous-sized fertile pollen grains along with reduced pollen fertility.

Cytomorphological studies of genus Saxifraga L. from Western Himalaya

Cytomorphological studies have been carried out for analysing the cyto-genetic diversity in 14 populations covering 5 species belonging to the genus Saxifraga L. (fam. Saxifragaceae) from Western Himalaya. New intraspecific cytotypes in Saxifraga diversifolia Wall. ex Ser. (n = 8 and n = 16), S. filicaulis Wall. ex Ser. (n = 8) and S. siberica Linn. (n = 16) are added on world-wide basis. Cytotypes of S. flagellaris Willd. (n = 8), S. ligulata Wall. (n = 17) and S. siberica Linn. (n = 8) although worked out earlier from other countries are being reported for the first time from India. Further, comparison of the different cytotypes studied at present for Saxifraga diversifolia Wall. ex Ser and S. siberica Linn. show significant variation in their morphology, and also increased size for morphphological features in the polyploids. The course of meiosis has been observed to be abnormal in all the populations of S. filicaulis Wall. ex Ser., S. flagellaris Willd. and S. siberica Linn., but in S. diversifolia Wall. ex Ser. it exhibited patterns of normal to abnormal behaviour in different populations.

An overview of chromosome and basic numbers diversity in cytologically investigated polypetalous genera from the Western Himalayas (India)

Intensive exploration and evaluation of cytomorphological diversity has been carried out on 380 species of 127 genera belonging to 28 families of sub-class Polypetalae of flowering plants from Kashmir (Jammu and Kashmir) and Kangra and Sirmaur districts (Himachal Pradesh) of the Western Himalayas. The cytological investigations of these species over a period of three years revealed new and varied chromosome numbers for 100 species globally and 50 species in India, making a substantial addition to the knowledge of the genera to which these species belong. To obtain a comprehensive cytological picture of each of these genera, chromosomal data have been updated by compiling the literature on previous chromosomal numbers and supplementing it from the present studies. The final form is now ready to show the status both at global and Indian levels for various parameters like total number of taxonomically known species, number of cytologically determined species along with intraspecifically added number of cytological taxa, presently inferred basic numbers, level and frequency of polyploids, and information on number of species per genus carrying inter- and intraspecific euploid and aneuploid variability at the genus level. Of the total 127 genera, 39 genera have 75% or more cytologically worked out species. Addition of cytotypes in many cytologically known species has resulted in an enhanced number of chromosomal races/cytological taxa over such species, in the majority of genera, justifying the ever growing need to make population based intensive studies of any plant species. The data show that monobasic and dibasic genera are less common than tribasic and polybasic ones. Genera with x = 8 are most common, followed by x = 7 and x = 6. Of 127 genera, 47 genera exhibit polyploidy of up to 25%; 22 genera have 26–50%; 15 genera have 51–70%; and 26 genera have 76–100% polyploidy, while 17 genera lack polyploidy altogether. Interspecific and/or intraspecific euploid cytotypes such as diploids plus polyploids or with “polyploid series” are present in most of the 107 genera. Intraspecific aneuploid chromosome numbers are also shown by 100 genera. Since these genera belong to different families, so no generalization can be made at family level. However, at genus level chromosomal observations show the active role of various evolutionary processes responsible for chromosomal diversity in the majority of these genera distributed in the Western Himalayas of India.

Cytological evaluation of Apiaceae Lindl. from Western Himalayas

The present paper deals with cytological studies on 31 populations covering 17 species belonging to 10 genera of Apiaceae from Western Himalayas. The chromosome numbers in the two species as Chaerophyllum capnoides (n = 11) and Heracleum brunonis (n = 11), along with additional cytotypes for Pimpinella acuminata (n = 9) and Sium latijugum (n = 12) have been reported for the first time on world-wide basis. The genus Pleurospermum, although cytologically worked out earlier from outside India, its species densiflorum (n = 11) makes first representation of the genus from India. Besides, the chromosome number in Chaerophyllum aromaticum (n = 11) have been worked out for the first time from India. The course of meiosis varies from normal to abnormal in different populations of Chaerophyllum villosum, Pimpinella achilleifolia and Sium latijugum while abnormal meiotic course has been observed in all the studied populations of Chaerophyllum acuminatum, C. aromaticum, C. capnoides, Pimpinella acuminata, P. diversifolia, Pleurospermum densiflorum and Vicatia coniifolia. Such taxa are marked with meiotic abnormalities in the form of cytomixis, chromatin stickiness, formation of laggards and bridges resulting into abnormal microsporogenesis. The occurrence of structural heterozygosity has been recorded in the Chaerophyllum acuminatum and C. aromaticum. The effect of these abnormalities is clearly seen on the pollen size and fertility.

Cytological studies of Brassicaceae Burn. (Cruciferae Juss.) from Western Himalayas

Cytological studies have been carried out on 12 species of Brassicaceae Burn. on population basis from different geographical areas of Kashmir and Himachal Pradesh in the Western Himalayas. Variable chromosome reports for Barbaraea intermedia (n = 16), Cardamine loxostemonoides (n = 8), Nasturtium officinale (n = 8), Sisymbrium orientale (n = 14) on world-wide basis have been added to the previous reports of these species. The chromosome numbers in seven species as Barbaraea intermedia (n = 8), B. vulgaris (n = 8), Capsella bursa-pastoris (n = 8), Descuriania Sophia (n = 10), Rorippa islandica (n = 8), Sisymbrium strictum (n = 7) and Thlaspi alpestre (n = 7) have been worked out for the first time from India. The meiotic course in the populations of seven species such as Barbaraea intermedia, Capsella bursa-pastoris, Coronopus didymus, Descuriania sophia, Nasturtium officinale, Sisymbrium orientale and S. strictum varies from normal to abnormal while all the populations of two species Barbaraea vulgaris and Sisymbrium irio show abnormal meiotic course. Meiotic abnormalities are in the form of cytomixis, chromosomal stickiness, unoriented bivalents, inter-bivalent connections, formation of laggards and bridges, all resulting into abnormal microsporogenesis. Heterogenous sized fertile pollen grains and reduced reproductive potentialities have invariably been observed in all the meiotically abnormal populations. However, the meiotic course in all the populations of Cardamine loxostemonoides, Rorippa islandica and Thalspi alpestre is found to be normal with high pollen fertility.

Identification of new cytotypes of Valeriana jatamansi Jones, 1970 (Valerianaceae) from North-Western Himalayan region of India

Abstract Valeriana jatamansi, a medicinally important species of the family Valerianaceae, has been cytologically studied in different geographical areas of North-Western Himalayan region of India. The tetraploid cytotype with chromosome numbers 2n=32 is in conformity with the earlier reports of the species from different parts of the world. An octoploid cytotype (2n=64) makes a new addition for the species on a worldwide basis, whereas the diploid cytotype (2n=16) is new to India have been reported for the first time in India. These cytotypes (2n=16, 32, 64) show significant variations with respect to morphology as well as geographical distribution in the Western Indian Himalayas. Further, anomalous populations have been marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges resulting in abnormal microsporogenesis, and production of heterogeneous-sized fertile pollen grains along with reduced pollen fertility.

Cytological and morphological characterization of rye-wheat derivatives for important agronomic traits

Ninety two derivatives derived from rye-wheat crosses were analyzed for their rye chromosome/chromatin constitution using molecular cytogenetic tools FISH and GISH, to detect targeted rye chromatin introgression with minimum linkage drag. Of the 92 recombinants lines analyzed, 17 exhibited one pair of rye chromosome substituting different chromosomes of A, B, and D genomes, 10 lines showed substitution and translocations at the same time and 55 lines had 1BL.1RS translocations. Four lines that had more than 10 chromosomes from rye were alike triticale, whereas remaining six lines exhibited no rye chromatin/chromosome. These lines were evaluated for different agronomic traits such as days to maturity, type of spike, colour of spike, compactness of spike etc. for ascertaining correlation between rye chromatin with morphological traits.

Variations of morphology, ecology and chromosomes of Aconitum heterophyllum Wall., an endangered Alpine medicinal plant in Himalayas

Cytology, morphology and ecology were determined from 21 natural populations of Aconitum heterophyllum in Kashmir and Ladakh Himalayas. Data revealed a high body of variability among various morphological characters including plant height, foliage, floral and tuber attributes at intra-population levels. Plant height varied from 98 ± 4.6cm to 36.1 ± 4.5cm. The tuber crude drug production values ranged from 1.22 to 1.7 g/plant. It was generally lower at lower altitudes and higher at higher altitudes. The number of flowers varied from nine to 11; however, it was directly linked with altitude. A similar trend was observed for number of seeds/fruit. Despite this variability, the species was restricted to specific ecological niches with critically low population density facing onslaught of over-exploitation. The present study contributes to insight some aspects of the cytogenetic diversity related to the distribution range of the studied populations with respect to different ecological factors. In addition, the chromosome study depicted that all the populations were diploid (2n = 16); however, the meiotic course varied from normal to abnormal with 11 populations showing abnormalities. These populations exhibited reduction of pollen fertilities up to 20–40% as well as formation of heterogeneous sized pollen grains.