Preliminary Results on the Effect of Magnetic Fields on Anther Culture and Pollen Germination of Citrus clementina Hort. ex Tan.

Exposure to electromagnetic fields seems to modify the biological behaviour of seeds, roots, pollen grains and buds of several plants. This procedure has been also suggested as a tool to improve the utilization of plant species (Firetto et al., 2000, 2001, Petruszewski S., 1996). Since the first haploid embryogenic calli production and plantlet regeneration by anther culture of C. clementina Hort. ex Tan. ‘Nules’ was reported (Germanà et al., 1994), several studies have been carried out to improve both the frequency of microspore embryogenesis and the percentage of plantlet regeneration. To enlarge the number of respondent genotypes and to improve the induction rate (the frequency of pollen grains which form embryoids) are fundamental goals in order to take practical advantage of the haploid potential in Citrus breeding. Successful recovery of haploids depends on several factors like genotype, pre-treatment, pollen development stage, media composition and cultural conditions. This research has been carried out to investigate the effect of magnetic field exposure on the response of Citrus clementina anthers to in vitro culture and the effect of the exposure to three different magnetic frequencies on pollen in vitro germination. The percentage of anthers producing callus was increased by exposure to the magnetic field. Magnetic field exposure also affected pollen germination as well as pollen tube length and morphology