Step 1: Understanding the Concept:
The genus Mangifera contains numerous wild and semi-cultivated species that serve as important genetic reservoirs for improving the commercial mango (Mangifera indica).
These wild species possess unique genes for abiotic stress tolerance (such as waterlogging or salinity), disease resistance, alternate bearing habits, and novel fruit characteristics.
Horticultural breeders utilize these species as rootstocks or parents in breeding programs to introduce these desirable traits into commercial cultivars.
Step 2: Detailed Explanation:
Let us match each trait with its corresponding wild Mangifera species to determine the correct sequence:
(A) Rootstock for water logged condition \(\rightarrow\) Mangifera decandra:
This wild relative of mango exhibits high tolerance to soil waterlogging and oxygen deprivation, making it a valuable rootstock for orchards in flood-prone areas.
Thus, (A) aligns with M. decandra.
(B) Fruits twice a year \(\rightarrow\) Mangifera indica var. Mekongensis:
This botanical variety, originating from the Mekong Delta, has a continuous flowering habit that produces fruit twice a year.
It is used to breed cultivars for off-season fruiting.
Thus, (B) aligns with M. indica var. Mekongensis.
(C) Good parent for breeding free stone mangoes \(\rightarrow\) Mangifera similis:
This species is characterized by a weak attachment between the seed coat (endocarp) and the surrounding pulp, making it a valuable parent for breeding free-stone cultivars.
Thus, (C) aligns with M. similis.
(D) Fruits can be peeled like banana \(\rightarrow\) Mangifera pajang:
Native to Borneo and known locally as Bambangan, this species produces fruit with a thick, leathery, and easily separable rind that can be peeled like a banana.
Thus, (D) aligns with M. pajang.
This matches the sequence: M. decandra - M. indica var. Mekongensis - M. similis - M. pajang, corresponding to option (D).
Step 3: Final Answer:
Therefore, the correct sequencing of the species is represented by option (D).