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Chromosome number and DNA content in cells of a biotechnologically selected somaclone of garlic (Allium sativum L.)

Benedicto de Campos Vidal^I; Maria Luiza S. Mello^I; Rolf D. IIIg^II

^IDepartamento de Biologia Cehilar
^IIDepartamento de Genética e Evohição, Instituto de Biologia, UNICAMP, 13081-970 Campinas, SP, Brasil. Send correspondenee to B.C.V.

ABSTRACT

A somaclonal variant of Allium sativum L., selected in vitro through biotechnological procedures, was characterized by increased vigour and high productivity, both unchanged after five cyeles of field cultivation. The sane chromosome number was found in somaclonal variant metaphase cells and those of a control (2n = 16). However, Feulgen-DNA values in metaphases and interphase nuclei of the somaclonal variant were shown to differ from those of the control, a 4.5% DNA increase being found in the somaclonal variant metaphases. The possibihty of gene amplification in the somaclonal variant cells could explain their slight increase in DNA content.

Keywords: Chromosome number; DNA content; Garlic; Allium sativum.

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