Infra Species Taxonomy of Seed and Graft Propagated Mango (Mangifera Indica L.) in Chapai Nawabganj

Abstract

Phenotypic variation and diversity of mango (Mangifera indica L.) of Chapai Nawabganj district in Bangladesh was investigated. The mango cultivars were studied for the qualitative and quantitative characters under the agro-climatic condition of Chapai Nawabganj region where mango grows extensively. A total of three hundred fifty seven trees were selected from the six villages named Bohalabari, Komolakantapur, Mirer chora, Chondipur, Shaheb gram and Noya lavanga for the assessment of thirty one qualitative characters and eleven quantitative characters of tree, leaf, inflorescence, fruit and stone following the Descriptor (IBPGR,1989 & IPGRI,2006). A wide range of variations were observed among the six villages and within the villages for both morphological and reproductive characters which indicated the existence of rich genetic diversity of mango in this region. The mango trees were grouped into three categories- ‘commercial varieties’, ‘cultivated varieties’ and ‘gutee’ trees to identify the pattern of phenotypic changes of variation among them. Two hundreds and seventy trees (90 from each category) were used for this purpose. The results strongly indicated a pattern of morphological change among the three categories. The differences in qualitative characters of the commercial varieties were more prominent than the cultivated varieties and ‘gutee’ trees. For quantitative characters, the commercial varieties showed better adaptation in respect to leaf, fruit and stone characters than the other two categories. Also, wide ranges of variations were observed among the mango trees grouped in two age groups (young and old). In this case, the differences for qualitative and quantitative characters were much pronounced in the commercial varieties whereas in ‘gutee’ trees it was least pronounced. The taxonomic study of mango was carried out to establish a suitable key for classification to identify them easily. The complete description of 14 local cultivars have been added which were not included earlier in any published monographs in Bangladesh. There were many locally cultivated varieties of mango which are superior in quality but not getting proper attention and become threatened or extinct before their documentation. Also the descriptions of hundred ‘gutee’ trees have been added as an indication of the richness of variations of diversity exists in the mango populations. These local cultivars and ‘gutee’ trees can be used to produce superior clones or in breeding programs. So it is important to put proper attention on to conserve these resources for future varietal development programme.