Abstract: (28956 Views)
The commercial potato is an autotetraploid species. Certain allotetraploid species such as S. acaule despite theire identical ploidy level are not crossable with commercial potato due to their different endosperm balance numbers. The aim of this experiment was to investigate the possibility of germplasm transferring from allotetraploid species to cultivated potato by the use of diploid species and 2n gametes. For this purpose, one clone of S. phureja was crossed with S.acaule. The resulting F1 seeds were planted the next year. For evaluation of male fertility and unreduced gametes, the pollen samples of F1 hybrids stained with acetocarmin glycerol were assessed. For chromosome counting the tips of stolons were fixed and after staining with aceto – iron- hematoxilin were squashed. For future crossing some hybrids were grafted on tomato stocks. Cytologycal observation revealed that hybrids were triplod. Male fertility of hybrids as expected for odd ploidy was low, but approximately all of them had a few large stainable pollen (putative 2n). crossing of the hybrids as male parent with S. tuberosum was not successful, but reciprocal cross was successful and 72 seeds were obtained from 380 pollination . considering EBN, it is exected that the resulting seeds originate from fertilization of unreduced gametes of triploid and n gamates of S. tuberosum to be pentaploid or near pentaploid. The applications of these hybrid in potato breeding via ploidy manipulation have been discussed.
Type of Study:
Research |
Subject:
Ggeneral Received: 2008/01/9 | Published: 2004/07/15