Tracking Selection Signatures Based on Variation in <i>OsLEA</i>27 within Myanmar Landraces of Upland and Dryland Rice

To track the selection evident along the genome segment of OsLEA27?gene, a member of dehydrin gene family, 2.9-kbp nucleotide sequence containing the promoter 5’ upstream and transcribed region of OsLEA27?was determined for 35 upland and dryland Myanmar landraces from drought-prone areas. Nucleotide diversity, neutrality tests, haplotype network analysis, and linkage disequilibrium (LD) analysis were performed to infer the impact of selection and to investigate nonrandom associations of SNPs within all or part of the entire OsLEA27?region. The evidence for LD, the presence of two distinct haplotype groups across four different geographical regions, and the significant values obtained in a sliding-window analysis of mutation-drift tests all suggest the effects of selection on OsLEA27?in a set of 30 landraces. The neutrality test values for 5’ upstream region of OsLEA27?were significantly negative (p OsLEA27 region was significantly negative in accessions of the northern group, indicating a recent increase in population size or selection pressure. This evidence for selection signatures at OsLEA27 in this study sample provides insight into the roles of selection, crop adaptation, and genetic diversity in establishing present-day variation at the OsLEA27 locus.

Description of Flower Biology of Under-Exploited Species, <i>Zingiber barbatum</i>(Wall.) from Myanmar

Characterization of the reproductive morphology in genus Zingiber is still relevant on classical taxonomic studies because most of the species are phenotypically similar and difficult to distinguish in the absence of the flowering stage. Reports mainly derived based on the herbarium collections are insufficient for the detailed morphological review. Zingiber barbatum (Wall.) belongs to the genus Zingiber and has been neglected for a long time. Existed intraspecific morphological and genetic variations also intricate the description of this species. The objective of this study was to characterize the reproductive morphology of under-exploited Z. barbatum species. The study was done based on the traditional description of morphology and habit of inflorescence and flowers, with a recording of minimum quantitative and qualitative parameters and phenological observation regarding inflorescence life span and duration of blossom. Assessment of reproductive morphology displayed phenotypic variations regarding inflorescences habit during the growth stage and morphological features of the flower. Perhaps, an existed variation was driven by eco-geographical factors resulting in reproductive isolation due to which genetic divergence might occur. The taxonomic affiliation of Z. barbatum based on inflorescence habit has been confirmed. This is the first comprehensive report regarding flower biology on Z. barbatum.