Determination Of The Nature Of Tetraploidy In Cassava Through Meiotic Analysis

Azucena  L. Carpena,; Celsa  F. Armecin,

Determination Of The Nature Of Tetraploidy In Cassava Through Meiotic Analysis

Abstract:

The prevalence of normal bivalent pairing at diakinesis and metaphase I and the high percentage of cells having regular meiosis suggest that cassava (Manihot esculenta Crantz) is an allotetraploid and not an autotetraploid. Based on the results, cassava seems to be a segmental rather than a true allotetraploid as indicated by the presence of multivalents and univalents in 29% of the total meiotic cells observed. This implies partial homology between the chromosomes of the species resulting in segmental pairing of homologous chromosomes. Therefore, cultivated cassava is a segmental allotetraploid with a basic chromosome number of x = 9 and a chromosome number of 2n = 4x = 36.

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