Abstract
Somaclonal variation in plants regenerated by organogenesis from long-term cultured calluses of two diploid staminate genotypes of Asparagus officinalis cv. Argenteuil was characterized by plant phenotype, ploidy, meiotic behavior, pollen viability, fruit and seed set, and AFLP profiles. Phenotypic deviations from the donors were detected in foliage color, flower size, and cladode and flower morphology. Ploidy changes were observed in 37.8% of the 37 regenerants studied. Meiotic alterations in 12 out of 21 regenerants included laggards, dicentric bridges, micronuclei, restitution nuclei and polyads. Of the 408 AFLP markers screened in 43 regenerants and the donors, 2.94% showed polymorphism. High pollen viability was observed in the 22 regenerants analyzed. All crosses between one pistillate plant and 35 regenerants, as well as the controls, produced fruits and seeds; however, no plump seeds resulted in 35.3% of the crosses with regenerants, and no seeds germinated in 12.5% of those with apparently normal seeds. Fruit and seed set was similar in crosses with diploid regenerants with normal meiosis and the controls but was lower in crosses with diploid and polyploid regenerants with abnormal meiosis. Our results show that the regenerated plants exhibited conspicuous somaclonal variation that could be eventually exploited for in vitro selection systems.
Highlights
Garden asparagus (Asparagus officinalis L.) is a vegetable of high economic value
Aberrant flowers with a higher than normal number of stamens occurred in two diploid, one triploid and two tetraploid regenerants derived from clone 265
Our results reveal conspicuous somaclonal variation in asparagus plants regenerated by organogenesis from long-term callus cultures
Summary
Garden asparagus (Asparagus officinalis L.) is a vegetable of high economic value. The main cause of asparagus crop decline in the world is the disease known as ‘crown and root rot’, caused by Fusarium spp. (Farr et al, 1989). The main cause of asparagus crop decline in the world is the disease known as ‘crown and root rot’, caused by Fusarium spp. Recovery of resistant asparagus cultivars through conventional breeding is hindered because Fusarium is ubiquitous in the soil, asparagus is perennial and dioecious, and disease resistance is subject to polygenic control (Lassaga et al, 1998). The application of in vitro selection techniques has facilitated the generation of disease resistant plants in other pathosystems (Crinò, 1997; Remotti, 1998). Many of these techniques exploit somaclonal variation that can arise or be detected during in vitro culture (Larkin and Scowcroft, 1981). Before applying in vitro selection it is essential to identify the conditions which favor somaclonal variation and to characterize such variation
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.