Taxonomic Investigation of Four Varieties of Mangifera Using Micro-Anatomical Features (Published)
Taxonomic investigation of four varieties of Mangifera was undertaken in this study. The aim was to explore the use of foliar micro-anatomical traits in resolving the lingering systematic challenges associated with this fruit crop. Leaves of four varieties of Mangifera (Big-no-fibre, Julie, Opioro and Small-fibre varieties) were collected across various locations in the North Central part of Nigeria. Eighty (80) permanent slides were prepared from the foliar abaxial and adaxial surfaces following standard microscopic practices. Micrometry was carried out using the calibrated ocular and stage micrometers mounted on the compound microscope. From each specimen, thirteen (13) characters were examined and analysed. Mean values of all characters were computed and analysed using the SPSS software (20.0 versions). Pearson’s correlation matrix was generated to ascertain the association among the characters. Dendrogram was constructed using the Ward’s method to classify the varieties on the basis of their similarities and differences. From the result obtained, the Julie mango had the longest epidermal cell length of 57µm (adaxial) followed by the Small-fibre type with 55.3µm (abaxial). Stomata and guard cell displayed huge qualitative and quantitative variation among the varieties. Comparison of the abaxial surfaces revealed that the Big-fibre variety had the highest stomatal index (78%) followed by the Opioro variety (62%). Conversely, the Small-fibre recorded the longest guard cells surrounding the stomata (44µm) while the Big-no-fibre had the shortest (30.3µm). Correlation revealed that SLD and ELA are positively correlated by +0.996. From the dendrogram, the Big-no-fibre was a distinct variety clearly delimited from the rest, but the Julie and Opioro types were more closely related than others. On this note, both the Big-no-fibre and Small-fibre may be assigned different varietal nomenclatures under Mangifera indica and solve the challenges associated with the common names. Micro anatomic features taxonomic audit of mangifera varieties successfully investigated in this study is maiden and novel. This is reported for the first time.
Keywords: Dendrogram, Mangifera indica, Micro anatomy, Micrometry, Varieties