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Karyotype analysis in parents and F1 seedling: a, Ensete superbum chromosome no. 2n = 18; b, Musa balbisiana chromosome no. 2n = 22; c, E. superbum × M. balbisiana chromosome no. 2n = 18.
Source publication
Intergeneric hybridization, especially in vegetatively propagated crop species involving wild relatives, is a common method to introgress desirable genes into the crop species. The family Musaceae has two genera, Musa and Ensete 1. An intergeneric cross was attempted between Ensete superbum (2n = 18) and Musa balbisiana (2n = 22) to transfer some c...
Contexts in source publication
Context 1
... studies to count the number of chromosomes were done using karyotyping techniques in both the parents and four putative 'hybrid seedlings'. The chromosome number of E. superbum and M. balbisiana was found to be 2n = 18 and 2n = 22 respectively ( Figure 2 a and b). All the four seedlings of putative hybrids observed had 2n = 18 chromosomes (Figure 2 c). ...
Context 2
... chromosome number of E. superbum and M. balbisiana was found to be 2n = 18 and 2n = 22 respectively ( Figure 2 a and b). All the four seedlings of putative hybrids observed had 2n = 18 chromosomes (Figure 2 c). This indicates that the seedlings might have inherited their diploid set of chromosomes from their female parent, E. superbum with 2n = 18, with no contribution from the male parent, M. balbisiana. ...
Citations
Banana is a nature’s gift to the mankind with four times protein, twice carbohydrates, three times phosphorus, five times vitamin A and iron, many times potassium and twice other vitamins and minerals compared to apple. It is under cultivation in more than 120 countries across the globe. It is referred as a food equivalent across major African countries, Latin America including Caribbean and Polynesian Islands. Therefore it has acquired the food-fruit status contributing towards food and nutritional security. This chapter describes the botany and taxonomy of banana, Musa genetic resources and their allied species available across the globe, the evolutionary history of various ploidies and genomes. This also provides elaborate practical guidelines for the successful collection of banana genetic resources. This includes strategies for germplasm collection, establishment of virus-free germplasm, characterization, conservation, documentation and their potential utilization in banana improvement. This deals with the current status and future research needs of various conservation strategies. This chapter recommends the strategic collection of genetic resources and indexing prior to establishment with special emphasis on application of advanced GIS tools in relation to ecological data for effective conservation.
The first attempt at breeding bananas through hybridization, in the 1920s was triggered by the devastation of the export banana ‘Gros Michel’ by Fusarium wilt. Conventional breeding despite being hindered by several plant based constraints has been responsible for the production of a whole range of hybrids resistant to diseases and pests. The approach commonly adopted aims at developing new tetraploid varieties by crossing triploids with wild or improved diploid clones with resistance, or secondary triploids derived from crosses between the developed tetraploids and the diploid clones. The limitations of the 3x/2x strategy are low gametic fertility of the triploid variety to be improved. This has led to the development of an alternate pathway, which targeted the development of triploid hybrids directly from crosses involving diploid and doubled diploid varieties. The method exploited the male and female fertility status of doubled diploids which otherwise are sterile at the diploid level. Following the 3x/2x method, hybrids with yield advantage and resistance to biotic stresses developed by major breeding programmes have been adopted in many countries, which was facilitated by the International Musa Testing Programme. The new insight gained in Musa genetic diversity through molecular tools provided key inputs, useful for the selection of parental combinations. Development of molecular markers linked to major traits is expected to speed up the improvement process. Mutation breeding is offering a unique, alternative approach for the improvement of banana has also been employed to develop new cultivars.
