## Mapping, combining abilities, heritabilities and heterosis with 4x x 2x crosses in potato |

### From inside the book

Results 1-3 of 13

Page 16

II. In order to simplify, SET.I plus SET. II may be equated to e (pi + p2), and SET.I x

SET. II to d (pi x p2). Although, e must be considered to be twice the m.d. with

respect to the centromere of the distal locus, this will be incorrect when at least

one DET.I + II occurs. Therefore, the m.d. with respect to the centromere is a

direct function of pi and p2. The m.d. for the

centromere will be 1/2 (pi + plp2), whereas for the distal locus it will be 1/2 (pi +

p2 + 2plp2).

II. In order to simplify, SET.I plus SET. II may be equated to e (pi + p2), and SET.I x

SET. II to d (pi x p2). Although, e must be considered to be twice the m.d. with

respect to the centromere of the distal locus, this will be incorrect when at least

one DET.I + II occurs. Therefore, the m.d. with respect to the centromere is a

direct function of pi and p2. The m.d. for the

**proximal locus**with respect to thecentromere will be 1/2 (pi + plp2), whereas for the distal locus it will be 1/2 (pi +

p2 + 2plp2).

Page 53

Frequency of 2n gametic output expected from FDR and SDR genotypes in

coupling phase «*» and repulsion phase "-with single and double crossovers for

a random chromatid exchange model. pi3* frequency of single exchange tetrads

between the centromere and the

exchange tetrads between the proximal and the distal locus. e= pi + pj«

frequency of single exchange tetrads between the centromere and the distal

locus . d= frequency of ...

Frequency of 2n gametic output expected from FDR and SDR genotypes in

coupling phase «*» and repulsion phase "-with single and double crossovers for

a random chromatid exchange model. pi3* frequency of single exchange tetrads

between the centromere and the

**proximal locus**. pj» frequency of singleexchange tetrads between the proximal and the distal locus. e= pi + pj«

frequency of single exchange tetrads between the centromere and the distal

locus . d= frequency of ...

Page 56

Using the formula in Table 9 (Expected Gametic Output of FDR-CC in Coupling

Phase) and replacing pj and P2 by the estimated values of recombination of the

13.42 x 2)], respectively, one finds a frequency of recombinant gametes of 0.2085

, which is very close to 0.2383, the frequency of unpigmented genotypes which

should have been observed with [dddd] female genotypes in group II. This means

, that ...

Using the formula in Table 9 (Expected Gametic Output of FDR-CC in Coupling

Phase) and replacing pj and P2 by the estimated values of recombination of the

**proximal**and distal**locus**[D], that is 26.84 (13.42 x 2) and 68.42 [(47.63 x 2) - (13.42 x 2)], respectively, one finds a frequency of recombinant gametes of 0.2085

, which is very close to 0.2383, the frequency of unpigmented genotypes which

should have been observed with [dddd] female genotypes in group II. This means

, that ...

### What people are saying - Write a review

We haven't found any reviews in the usual places.

### Contents

Genetic Mapping of Three Linked Genes | 34 |

Results | 78 |

Comparisons between 2x FDRCO and 2x FDRNCO | 94 |

2 other sections not shown

### Common terms and phrases

2n eggs 2n gamete formation 2x clones 2x crosses 2x FDR-CO 2x genotypes 2x level 2x parents 4x cultivars 4x progeny 4x x 2x centromere chromosome combining abilities coupling phase cytokinesis depending on frequency diploid distal locus division restitution dominance variance double crossovers double exchange tetrads endosperm epistasis epistatic estimates expressed as map FDR and SDR FDR or SDR form 2n gametes form 2n pollen Frequencies of parental frequency of single gametic series produced GCA variance genotypes in coupling haploid heterosis heterozygosity heterozygous heterozygous loci homozygous linked genes map units marketable tuber yield meiocytes mode of 2n periderm Phureja ploidy polyploidization potato progenies from 4x proximal locus random chromatid exchange repulsion phase rH rH S. J. Peloquin SDR mode SET.I single and double single exchange tetrads Solanum Solanum tuberosum specific gravity Table tetrad analysis tetraploid total tuber yield tuber shape types of 2n unpigmented