ORIGINAL ARTICLE Floral biology in relation to meiotic system in Buxus wallichiana Baill.: an endemic temperate tree species of North-West Himalayas Eshan Sharma 1 • Uma Bharti 1 • Upvan Bhushan 1 • Namrata Sharma 1 Received: 29 April 2016 / Accepted: 3 February 2017 Ó Archana Sharma Foundation of Calcutta 2017 Abstract Buxus wallichiana Baill., an economically important slow growing, endemic tree species of family Buxaceae forms populations at high altitudinal areas of North-West Himalayas. Chromosome numbers for genus Buxus are reported to be based on x = 7 and 14. B. wal- lichiana has been reported to be a diploid species. No chromosome number has however been given for this species prior to this study, which reveals its chromosome number as 2n = 28. This goes with basic number, x = 14 showing this species to be diploid. The species displays endodormancy as the area experiences heavy snowfall and chilling temperature during winter months. The buds dif- ferentiate in autumn and remain closed till the spring comes. Majority of the flowers bloom during the months of February–March as the snow melts in the area of study. This communication puts on record the details of meiotic system in this species for the first time. An attempt has been made to correlate it to the floral biology. Keywords Buxus wallichiana Á Cyathium Á Dormancy Á Floral biology Á Meiotic system Á Monoecious Introduction Buxus wallichiana Baill. (F: Buxaceae) is an economically important endemic tree species of North-West Himalayas. Wood of this tree is fine grained and does not need any polish. It is thus used in manufacturing of several household utilities including utensils, combs and decora- tion items. This species holds a whole cottage industry in several areas of Jammu and Kashmir State, India [22]; and is thus highly exploited. As a part of coordinated efforts to decipher breeding system of Rare Endangered Threatened (RET) tree species under a Ministry of Environment and Forests (MoEF) sponsored project, we conducted field surveys in different parts of Jammu and Kashmir State, India to locate populations of B. wallichiana. These sur- veys led us to identify populations at seven different sites. Two distinct sites i.e. Noori Chamb (1876 masl) and Mandi (1489 masl) of Jammu province were finally selected for detailed studies on breeding and meiotic system of this species. Both these aspects of this economically important and endemic taxon are hitherto unreported. Major aim of the study was to see bottlenecks in propagation, if any, in the populations of this species in nature and to suggest ways for easy regeneration. The paper here tries to elabo- rate the details of meiotic studies in relation to floral phenology of the species in the study area. Materials and methods Studies have been carried out on a North-West Himalayan tree species, B. wallichiana Baill. form distinct strands at an altitudinal range of 1450–2500 masl in Jammu and Kashmir State, India (Fig. 1a). The area of occurrence experiences chilling weather during winter months because of heavy snowfall (Av. temp. 13.66 °C). A total of 07 populations of the species were identified and tagged using local herbaria and floras [25]. Of these, two populations located at Noori Chamb (1876masl) and Mandi (1489 masl) consisting of 80 and 53 trees respec- tively, were chosen for detailed studies (Table 1). & Namrata Sharma phyllanthus@rediffmail.com 1 Department of Botany, University of Jammu, Jammu, J&K 180 006, India 123 Nucleus DOI 10.1007/s13237-017-0198-3