Tropical and subtropical fruits (2+1)

Species and cultivars

Species and cultivars: The family musaceae has two genera viz.,. Ensete and Musa with about 50 species.

1. Ensete-It is an old genus, which probably originated in Asia and spread to Africa. It has about 6-7 species, of which Ensete and Ventricosa has been reported to be grown as a food crop.
2. Musa –It is having 40-45 species, all the varieties under these species are under cultivation. The genus Musa is divided into following sections.
• Eumusa (2n=22): This is the largest section with 13-15 species, all are cultivated forms; Pseudostem usually exceed 3 m in height with pendent or semi pendent inflorescence, produces 10-25 nodes of flowers and covered with dull brown colour bracts, gives the edible cultivated parthenocarpic banana and are derived from 2 wild species. Musa accuminata (A) and Musa balbisiana (B).
• Callimusa: (n=10) -It is having 5-6 species. Plants with less than 3 mtrs in height, suited as ornamental, parthenocarpy absent completely.
• Australimusa (2n=20)- These fruits are parthenocarpic and predominantly female sterile; The fruiting bunch is erect and contains a red sap, the skin is orange in colour when ripe. eg-Musa textilis (Manila hemp).
• Rhodochlamys (2n=22) -It is having 5-7 species, spreads from India to Indonesia, pseudostem less than 3m height with erect inflorescence, parthenocarpy absent eg-M. ornate & M velutina are sometimes grown as ornamental plants.
• Incertae sedis- (x=7; 2n=14) - It is the largest among the Musaceae family, grows to a height of over 10m. eg-M. ingens & M. beccarii (x=9, 2n=18).
All the edible bananas are descendents by natural cross between 2 wild ancesters, ie., Musa acuminata (A) and Musa balbisiana (B).
These edible bananas have 22, 33 or 44 chromosomes i.e., Diploids, Triploids and Tetraploids respectively. Triploid cultivars are generally numerous, diploids somewhat less and tetraploid forms are very rare. The basic haploid numbers is 11.
Simmonds and Shephered (1995) have distinguished the major morphological charecters of M. acuminata and M. balbisiana, which are as follows;

Sl.No	Characters	Musa acuminata	Musa balbisiana
1	colour of pseudostem	Heavily marked with black or brown blotches	Blotches slightly or absent
2	Peduncle	Usually downy or hairy	Glabrous
3	Pedicel	Short	Long
4	Ovules	Two regular rows in each loculus	Four irregular rows in each loculus.
5	Bract curling	Bracts roll after opening	Bracts lift but do not roll
6	Bract shape	Lancedote or narrowly ovate tepering sharply.	Broadly ovate not tapering sharply
7	Bract apex	Acute	Obtuse.
8	Bract colour	Red, dull purpose or yellow outside, pink dull purple inside.	Brownish purple outside bright crimson inside.
9	Male flowers colour	Creamy white	Variably flushed with pink.
10	Stigma colours	Orange or rich yellow	Cream, pale yellow.
The best known banana all over the world belong to the pure acuminata (AAA) group but the clones which are having both the parents is associated with the greater drought tolerance and resistance to diseases. Eg-AB, AAB, ABB, AA or AAA-suited for rainy condition.