INTRODUCTION OF NEW CHARACTERISTICS AND GENETIC MAPPING USING THE HYBRIDS BETWEEN JAPANESE PEAR CV. ‘OSA NIJISSEIKI’ AND EUROPEAN PEAR P₁ CV. ‘OHARABENI’

In order to introduce new characteristics to Japanese pear from European pear such as a red color trait on fruit skin and some disease resistance to black spot, pear scab and pear rust and to apply the genetic mapping in Japanese pear, the hybrids between Japanese pear cv. ‘Osa Nijisseiki’ and European pear F₁ cv. ‘Oharabeni’ were bred.
The phenotypes of leaf color (red, green), S-genotypes using the S-gene-specific PCR, isozyme phenotypes in the seven loci with five kinds of isozyme and the disease response to black spot and pear scab were evaluated and analysed using the 90 progenies.
These phenotypes were segregated to a 1:1 ratio as expected.
On the other hand, four hundreds and seven random sequence primers were screened by a pseudo-testcross method to construct the linkage maps using the parents and the progenies. 79 kinds of the RAPD markers originating from each parent (‘Osa Nijisseiki’: 22 markers, ‘Oharabeni’: 57 markers) and showing a 1:1 segregation ratio were obtained in the final screening.
The two linkage maps were constructed from the segregation data of some phenotypes and the RAPD makers using a MAPL98 mapping software.
The linkage map of ‘Osa Nijisseiki’ consisted of 7 linkage groups spanning 191.1cM, in which two loci of an isozyme, susceptible gene (A) of black spot and self-compatible gene of S4^sm were mapped.
The other linkage map of ‘Oharabeni’ consisted of 13 linkage group spanning 470.7cM, in which two loci of the isozyme and the phenotype of red leaf were mapped.

International Symposium on Asian Pears, Commemorating the 100th Anniversary of Nijisseiki Pear

K. Banno, S. Saito, M. Robbani, H. Ishikawa

Pyrus pyrifolia, breeding, red color trait, black spot, pear scab, isozyme, RAPD marker, linkage map

https://doi.org/10.17660/ActaHortic.2002.587.27