Ploidy dependence of chromosomal variation in callus cultures ofHyoscyamus muticus L.

• DOI: 10.1007/bf01323256
• Publication Date: 2005-03-26T12:38:05Z
• Authors: U. C. Lavania; Sangeeta Srivastava
• Keywords: Callus; Chromosome number

Remarkable variation for chromosome number was observed in both diploid (2x) and autotetraploid (4x) callus cultures continuously examined for 12 months at monthly subsculture intervals. Initially, the subcultures exhibited predominantly the genomic level of the starting material which subsequently and gradually developed into heterogenous populations of euploid and aneuploid cells imparting the subcultures a aneusomatic status. The comparison of chromosomal instability recorded in 2x vs. 4x callus cultures revealed that with time both types of calli stabilized at a chromosome number around the 4x level. However, the chromosomal examination of the adventitious roots emerging from the disorganized calli revealed the euploid (both 2x and 4x) chromosome levels suggesting the occurrence of a“morphogenetic sieve”.