Material and methods
Chlorophytum laxum was collected from scrub forests of
Narthamalai, Pudukottai district of Tamil Nadu, India (Fig. 1).Chlorophytum kolliensis was collected from Kolli hills, Namakkal
district, Tamil Nadu (Fig. 2). The collected specimens were preserved
following standard protocols. The morphological comparison was done from
the herbarium deposits at MH and RHT (for herbarium acronyms, see Thiers
2017) along with relevant literature. In addition, digital specimens
from online resources, such as Kew Herbarium Catalogue
(http://apps.kew.org/herbcat/navigator.do) and the Plants of the
World online (http://www.plantsoftheworldonline.org/) were also
referred.
Sequencing of rbcL , matK and trnL-trnF regions ofChlorophytum species were done at Rajiv Gandhi Centre for
Biotechnology, Thiruvananthapuram, Kerala, India. The sequences were
submitted to NCBI and the accession numbers are OP028638 and OR542640.
The sequences were aligned using Clustal W and phylogenetic tree was
constructed using the maximum likelihood (ML) method with the following
options: 1000 bootstrap replication phylogeny test, Tamura 3-Parameter
Model, Gamma distributed (G) using MEGA software (Zhu et al .
2018). The T3P model was identified by jModeltest as the best fitting
substitution model based on AIC and BIC criteria (Posada 2008).
Scanning Electron Microscope (Carel Zeiss, EVO-18) image of seed, anther
lobe and pollen were obtained from ACIC, St.Joseph’s College,
Tiruchirappalli, Tamil Nadu, India and free hand section of tuberous
roots of Chlorophytum and safaranin staining were carried out at
Department of Botany, St.Joseph’s College, Tiruchirappalli, Tamil Nadu,
India.