ORIGINAL ARTICLE Male meiosis, morphometric analysis and natural propagation in the 23 and 33 cytotypes of Tordyliopsis brunonis (Apiaceae) from northwest Himalayas (India) Puneet Kumar • Pawan Kumar Rana • Vijay Kumar Singhal Received: 17 July 2013 / Accepted: 15 December 2013 / Published online: 31 December 2013 Ó Springer-Verlag Wien 2013 Abstract Tordyliopsis brunonis (Apiaceae) is cytologi- cally investigated here for the first time from India. The chromosome count of 2n = 33, ascertained here, represents a new intraspecific triploid cytotype in the species, supple- menting the earlier report of a diploid cytotype with 2n = 22 from Nepal Himalayas. The diploid chromosome count (n = 11) has also been found in some of the presently investigated individuals which showed perfectly normal meiosis with 100 % pollen fertility and normal seed set. However, the individuals with triploid chromosome count showed irregular meiotic behaviour and abnormal micro- sporogenesis resulting in high pollen sterility (56.26 %) and no seed set. The irregular meiotic behaviour in the triploid individuals is attributed to the occurrence of variable number of univalents (1–7) at diakinesis and metaphase-I. In the subsequent meiotic stages, these univalents lagged at ana- phases and constituted micronuclei in sporads. The triploid plants were also observed for natural propagation and it was noticed that no seeds were set. These plants were noticed to propagate vegetatively by rootstocks. Chromosomal pairing in triploid cytotype is typical of an allopolyploid. Based on the characterization of chromosomal pairing during meiosis, we assumed that the triploid individuals are probably allo- ploid in nature. Hypotheses concerning the possible origin of allotriploid in T. brunonis are also discussed. Keywords Apiaceae  Tordyliopsis brunonis  Triploid  Cytotype  Meiosis  Pollen sterility  Manimahesh hills  Chamba  India Introduction Tordyliopsis brunonis DC. (Apiaceae), a member of monotypic genus, Tordyliopsis (Tribe: Tordylieae) is also included under the genus Heracleum L. as H. brunonis (DC.) C.B. Clarke (Hiroe 1958, 1979; Cannon 1978). According to de Candolle (1830), both the genera (Tordyliopsis and Heracleum) are separate and can be differentiated on the basis of well-developed bracts and bracteoles. Endlicher (1839) and Meisner (1843) also accepted Tordyliopsis as a separate genus. Some of the recent researchers who have worked on the Himalayan Umbelliferae (Mukherjee and Constance 1993; Watson 1998a, b, 1999) have also advo- cated and supported the separation of Tordyliopsis from Heracleum. Russian researcher, M. G. Pimenov engaged in the study of nomenclature, geography, karyotaxonomy and distribution of species of family Umbelliferae, regarded Tordyliopsis as an independent monotypic genus on the basis of detailed studies on the original collections made from German-Chinese expeditions to Xizang (Tibet), an autonomous region and adjacent areas (Pimenov et al. 2000). Phylogenetic analysis of molecular data has also supported the placement of Tordyliopsis in the monophy- letic tribe Tordylieae subtribe Tordyliinae (Downie et al. 2010). Here, in this study, we considered the species under the genus Tordyliopsis. Tordyliopsis brunonis is a perennial pubescent herb with white flowers (Fig. 1). It is a clump-forming species with erect, slender, simple or sparingly branched stem, and bases clothed in fibrous remnant sheaths. The species grows in P. Kumar (&)  P. K. Rana  V. K. Singhal Department of Botany, Punjabi University, Patiala 147002, Punjab, India e-mail: puneetbotcyto@gmail.com P. K. Rana e-mail: pawanbotany@gmail.com V. K. Singhal e-mail: vksinghal53@gmail.com 123 Plant Syst Evol (2014) 300:1477–1486 DOI 10.1007/s00606-013-0975-7