Solanum phureja genes are expressed in the leaves and tubers of aneusomatic potato dihaploids

Abstract

The expression of leaf isozymes and tuber patatin in dihaploids derived from the Solanum tuberosum cv. Pentland Crown was investigated . Seven of the dihaploids were aneusomatic containing additional chromosomes from the S. phureja dihaploid inducer . Of these, four genotypes expressed leaf isozymes characteristic of the S. phureja dihaploid inducer, and the tubers of three aneusomatic dihaploids contained a S . phureja form of patatin . Aneusomatic dihaploids in which the proportion of cells containing additional S. phureja chromosomes was relatively small (i .e. 1-15 %) did not express leaf isozyme markers or patatin bands characteristic of the dihaploid inducer or showed only faint expression of one or two markers . However, those with a high proportion of cells containing additional chromosomes (50-55%) had a range of strongly expressed leaf isozymes that were characteristic of the dihaploid inducer and also expressed the S. phureja tuber patatin.One dihaploid genotype was exclusively euploid (2n = 24), yet is expressed a S. phureja leaf isozyme marker and S. phureja tuber patatin, suggesting recombination or chromosome substitution between the genome of the S phureja dihaploid inducer and the cultivar Pentland Crown .

Resistance to viruses in F1 hybrids produced by direct crossing between diploid Solanum series Tuberosa and diploid S. brevidens (series Etuberosa) using S. phureja for rescue pollination

“…The results reported here are in accordance with the reports of Clulow et al (1991Clulow et al ( , 1993 who found that (di)haploids may contain and express genes from the S. phureja pollinator. In addition to intergenomic translocation, our results suggest that chromosome elimination could have taken place, because TET38.2 and TET38.9 have a diploid (2n = 24) chromosome number (Watanabe et al 1995).…”

“…It is widely believed that potato (di)haploids (2n = 24) develop exclusively from unfertiUzed egg cells by parthenogenesis through the mechanism described above. However, recent studies using molecular techniques have shown that a significant proportion of (di)haploids may develop from fertilized ovules through the elimination of S. phureja chromosomes from triploid zygotes (Clulow et al 1991, Waugh et al 1992. Thus, many (di)haploids of 5. tuberosum may contain chromosomes or chromosome fragments from S. phureja.…”

“…Thus, many (di)haploids of 5. tuberosum may contain chromosomes or chromosome fragments from S. phureja. However, more importantly, the genes integrated from S. phureja can be expressed in the aneusomatic (Clulow et al 1993) and euploid (di)haploids (Wilkinson et al 1995), which may offer possibilities for the introduction of additional genes while maintaining haploid extraction as the major target.…”

The effect of NaCl on antioxidant enzyme activities in potato seedlings

“…Protein and enzyme extraction: One gram of frozen shoots was homogenized in 1 cm 3 of an ice cold solution containing 100 mM Tris-HCl (pH 7), 20 % glycerol, 1 % PVP (Clulow et al 1993). The homogenate was then centrifuged for 30 min at 18 000 g. A portion of the eluent was analyzed immediately for catalase activity, and the remainder was stored at -20 °C for subsequent analysis of SOD, POD and APX.…”

Evidence for somatic translocation during potato dihaploid induction

“…somes usually also contain DNA markers and/or isozyme markers specific to the dihaploid inducer (Clulow et a!., 1991(Clulow et a!., , 1993. Clearly, such dihaploids cannot be regarded as gametic samples and, as they are chimeric for chromosome number, their value for genetical studies is limited.…”