Marker-Assisted Selection of Trees with MALE STERILITY 1 in Cryptomeria japonica D. Don

Abstract

<jats:p>The practical use of marker-assisted selection (MAS) is limited in conifers because of the difficulty with developing markers due to a rapid decrease in linkage disequilibrium, the limited genomic information available, and the diverse genetic backgrounds among the breeding material collections. First, in this study, two families were produced by artificial crossing between two male-sterile trees, ‘Shindai11’ and ‘Shindai12’, and a plus tree, ‘Suzu-2’ (Ms1/ms1) (S11-S and S12-S families, respectively). The segregation ratio between the male-sterile and male-fertile trees did not deviate significantly from the expected 1:1 ratio in either family. These results clearly suggested that the male-sterile gene of ‘Shindai11’ and ‘Shindai12’ is MALE STERILITY 1 (MS1). Since it is difficult to understand the relative positions of each marker, due to the lack of a linkage map which all the closely linked markers previously reported are mapped on, we constructed a partial linkage map of the region encompassing MS1 using the S11-S and S12-S families. For the S11-S and S12-S families, 19 and 18 markers were mapped onto the partial linkage maps of the MS1 region, respectively. There was collinearity (conserved gene order) between the two partial linkage maps. Two markers (CJt020762_ms1-1 and reCj19250_2335) were mapped to the same position as the MS1 locus on both maps. Of these markers, we used CJt020762 for the MAS in this study. According to the MAS results for 650 trees from six prefectures of Japan (603 trees from breeding materials and 47 trees from the Ishinomaki natural population), five trees in Niigata Prefecture and one tree in Yamagata Prefecture had heterozygous ms1-1, and three trees in Miyagi Prefecture had heterozygous ms1-2. The results obtained in this study suggested that ms1-1 and ms1-2 have different geographical distributions. Since MAS can be used effectively to reduce the labor and time required for selection of trees with a male-sterile gene, the research should help ensure that the quantity of breeding materials will increase to assist future tree-breeding efforts.</jats:p>

Identification and genetic diversity analysis of a male-sterile gene (MS1) in Japanese cedar (Cryptomeria japonica D. Don)

“… 13 , Saito et al 6 Shindai-11 ms1 / ms1 4-bp Uonuma City, Niigata Prefecture, Japan Moriguchi et al . 27 Shindai-12 ms1 / ms1 4-bp Uonuma City, Niigata Prefecture, Japan Moriguchi et al . 27 Tahara-1 ms1 / ms1 4-bp Hadano City, Kanagawa Prefecture, Japan Saito 46 Naka-4 Ms1 / ms1 4-bp Hadano City, Kanagawa Prefecture, Japan Saito 17 Suzu-2 Ms1 / ms1 4-bp Suzu City, Ishikawa Prefecture, Japan Saito 17 Ooi-7 Ms1 / ms1 30-bp Haibara-gun, Shizuoka Prefecture, Japan Saito 17 …”

“…These amino-acid sequence mutations are likely to result in the malfunction of the lipid transfer protein coded by CJt020762. Fourth, the cross between an individual with homozygous for the 4-bp deletion ( ms1-1 / ms1-1 ) and an individual with heterozygous for the 4-bp deletion ( Ms1 / ms1-1 ) resulted in 1:1 ratio of the male-sterile and male-fertile offspring in both of two families (i.e., ‘Shindai-11’ × ‘Suzu-2’ and ‘Shindai-12’ × ‘Suzu-2’) 27 . Futhermore, the male-sterile and male-fertile offsprings always had the 4-bp deletion homozygously and the 4-bp deletion heterozygously in CJt020762, respectively 27 .…”

“…Fourth, the cross between an individual with homozygous for the 4-bp deletion ( ms1-1 / ms1-1 ) and an individual with heterozygous for the 4-bp deletion ( Ms1 / ms1-1 ) resulted in 1:1 ratio of the male-sterile and male-fertile offspring in both of two families (i.e., ‘Shindai-11’ × ‘Suzu-2’ and ‘Shindai-12’ × ‘Suzu-2’) 27 . Futhermore, the male-sterile and male-fertile offsprings always had the 4-bp deletion homozygously and the 4-bp deletion heterozygously in CJt020762, respectively 27 . The fifth piece of evidence suggesting that CJt020762 is the causative gene of MS1 comes from the mapping family ‘Fukushima-1’ × ‘Ooi-7’, where male-sterility occurred in one-half of offsprings 22 .…”

Somatic Embryogenesis and Plant Regeneration from Sugi (Japanese Cedar, Cryptomeria japonica D. Don, Cupressaceae) Seed Families by Marker Assisted Selection for the Male Sterility Allele ms1

“…In addition, markers tightly linked to the MS1 gene or derived from a putative MS1 gene have been developed [ 4 , 10 , 11 , 12 , 13 ]. These studies enabled marker-assisted selection (MAS) to select trees with ms1 [ 14 ].…”

Genetics and Improvement of Forest Trees

“…Finally, two papers report on practical research. Moriguchi et al [18] present the successful results of MAS of male sterility in C. japonica. Nagano et al [19] report advanced results of GS in the same species.…”