Kushida A.,Japan National Agriculture and Food Research Organization |
Tazawa A.,Hokkaido Research Organization Tokachi Agricultural Experiment Station |
Aoyama S.,Hokkaido Research Organization Kamikawa Agricultural Experiment Station |
Tomooka N.,Japan National Institute of Agrobiological Science
Genetic Resources and Crop Evolution | Year: 2013
Soybean cyst nematode (Heterodera glycines; SCN) is becoming a serious problem in azuki bean (Vigna angularis var. angularis) production in Hokkaido, Japan. To find sources of resistance to SCN, we screened wild relatives of azuki bean and calculated "female indices" (FIs) of 342 accessions from 8 Vigna species that are cross-compatible with azuki bean. Twenty-three accessions belonging to V. hirtella, V. minima, V. nakashimae, V. riukiuensis, and V. tenuicaulis were resistant to the most prevalent SCN race, race 3, but most of them were only moderately resistant or susceptible to race 5. Four promising accessions (V. minima JP205886, JP205891, and JP210806, and V. nakashimae JP107879) showed a high level of resistance to all SCN races found in Japan (1, 3, and 5) and race 2 (an experimentally derived race from race 5). Since the SCN-resistant soybean cultivars released in Japan are not resistant to races 2 and 5, these wild Vigna accessions may have resistance mechanisms different from that of soybean. Continuous culture of race 3 on promising accessions showed that it might be difficult to overcome the resistance of these accessions. The resistance sources found in this study will be useful in controlling SCN through the breeding of SCN-resistant azuki bean cultivars. This study also showed the effectiveness of using wild genetic resources for identifying novel resistance sources. © 2012 The Author(s).
PubMed | Japan National Institute of Agrobiological Science, Japan National Agriculture and Food Research Organization and Hokkaido Research Organization Tokachi Agricultural Experiment Station
Type: Journal Article | Journal: Breeding science | Year: 2015
Lodging tolerance (LT) is an important trait for high yield and combine-harvesting efficiency in soybean [Glycine max (L.) Merr.]. Many previous studies have investigated quantitative trait loci (QTLs) for lodging score (LS) in soybean. Most of the investigated QTLs were located in the proximal region of maturity or growth habit loci. The aim of this study was to identify genetic factors for LT not associated with maturity or growth habit. QTL analysis was performed using a recombinant inbred line (RIL) population derived from a cross between Toyoharuka (TH), a lodging-tolerant cultivar, and Toyomusume (TM). The genotypes of TH and TM were estimated as both e1e2E3E4 and dt1. The average LS over 4 years was used for QTL analysis, identifying a major and stable QTL, qLS19-1, on chromosome 19. The LS of the near-isogenic line (NIL) with the TH allele at Sat_099, the nearest marker to qLS19-1, was significantly lower than the NIL with the TM allele at that position. The TH allele at Sat_099 rarely had a negative influence on seed yield or other agronomic traits in both NILs and the TM-backcrossed lines. Our results suggest that marker-assisted selection for qLS19-1 is effective for improving LT in breeding programs.
Yamaguchi N.,Hokkaido Research Organization Tokachi Agricultural Experiment Station |
Kurosaki H.,Hokkaido Research Organization Central Agricultural Experiment Station |
Ishimoto M.,Japan National Institute of Agrobiological Science |
Kawasaki M.,Hirosaki University |
And 2 more authors.
Plant Production Science | Year: 2015
Early maturity is an important trait for soybean [Glycine max (L.) Merr.] growing in Hokkaido where the growing period is restricted because of the short fall season and early snowfall. Development of an early-maturing line without decreased seed yield is difficult because of the positive correlation between days to maturity and seed yield. In this study, we developed two breeding lines, Tokei 1067 (T1067) and Toiku 251 (T251), that were derived from crosses between Japanese and Polish cultivars. T1067 and T251 had a significantly earlier maturing time than Yukihomare (YH), the standard cultivar in Hokkaido. The seed yield of T251 was similar to that of YH. Moreover, the chilling tolerance levels of the T1067 and T251 lines at the flowering stage were greater than the tolerance level of YH. © 2015, Crop Science Society of Japan. All rights reserved.
Senda M.,Hirosaki University |
Nishimura S.,Hirosaki University |
Kasai A.,Hirosaki University |
Yumoto S.,Akita |
And 4 more authors.
Breeding Science | Year: 2013
In soybean, the I gene inhibits pigmentation over the entire seed coat, resulting in yellow seeds. It is thought that this suppression of seed coat pigmentation is due to naturally occurring RNA silencing of chalcone synthase genes (CHS silencing). Fully pigmented seeds can be found among harvested yellow seeds at a very low percentage. These seed coat pigmented (scp) mutants are generated from yellow soybeans by spontaneous recessive mutation of the I gene. A candidate for the I gene, GmIRCHS, contains a perfect inverted repeat (IR) of a CHS pseudogene (pseudoCHS3) and transcripts of GmIRCHS form a double-stranded CHS RNA that potentially triggers CHS silencing. One CHS gene, ICHS1, is located 680 bp downstream of GmIRCHS. Here, the GmIRCHS-ICHS1 cluster was compared in scp mutants of various origins. In these mutants, sequence divergence in the cluster resulted in complete or partial loss of GmIRCHS in at least the pseudoCHS3 region. This result is consistent with the notion that the IR of pseudoCHS3 is sufficient to induce CHS silencing, and further supports that GmIRCHS is the I gene. ©2013 by JAPANESE SOCIETY OF BREEDING.
PubMed | Hokkaido Research Organization Tokachi Agricultural Experiment Station and Hirosaki University
Type: | Journal: Planta | Year: 2016
Defective cracking frequently occurs in buff-pigmented soybean seed coats, where proanthocyanidins accumulate and lignin is deposited, suggesting that proanthocyanidins and/or lignin may change physical properties and lead to defective cracking. In the seed production of many yellow soybean (Glycine max) cultivars, very low percentages of self-pigmented seeds are commonly found. This phenomenon is derived from a recessive mutation of the I gene inhibiting seed coat pigmentation. In Japan, most of these self-pigmented seeds are buff-colored, and frequently show multiple defective cracks in the seed coat. However, it is not known why cracking occurs specifically in buff seed coats. In this study, quantitative analysis was performed between yellow and buff soybean seed coats. Compared with yellow soybeans, in which defective cracking rarely occurs, contents of proanthocyanidins (PAs) and lignin were significantly higher in buff seed coats. Histochemical data of PAs and lignin in the seed coats strongly supported this result. Measurements of the physical properties of seed coats using a texture analyzer showed that a hardness value was significantly decreased in the buff seed coats. These results suggest that PA accumulation and/or lignin deposition may affect the physical properties of buff seed coats and lead to the defective cracking. This work contributes to understanding of the mechanism of defective cracking, which decreases the seed quality of soybean and related legumes.
PubMed | Hirosaki University and Hokkaido Research Organization Tokachi Agricultural Experiment Station
Type: Journal Article | Journal: Breeding science | Year: 2014
In Hokkaido, northern Japan, soybean [Glycine max (L.) Merr.] crops are damaged by cold weather. Chilling temperatures result in the appearance of cracking seeds (CS) in soybean crops, especially those grown in eastern and northern Hokkaido. Seed coats of CS are severely split on the dorsal side, and the cotyledons are exposed and frequently separated. CS occurrence causes unstable production because these seeds have no commodity value. However, little is known about the CS phenomenon. The aims of this study were to identify the cold-sensitive stage associated with CS occurrence and to develop a method to select CS-tolerant lines. First, we examined the relationship between chilling temperatures after flowering and CS occurrence in field tests. The average temperature 14 to 21 days after flowering was negatively correlated with the rate of CS. Second, we evaluated differences in CS tolerance among soybean cultivars and breeding lines in field tests. Toyohomare and Toiku-238 were more CS-tolerant than Yukihomare and Toyomusume. Third, we developed a selection method in which plants were subjected to 21-day chilling-temperature treatment from 10 days after flowering in a phytotron. This enabled comparisons of CS tolerance among cultivars. This selection method will be useful for breeding CS-tolerant soybeans.
PubMed | Hokkaido Research Organization Tokachi Agricultural Experiment Station
Type: Journal Article | Journal: Breeding science | Year: 2012
Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is one of the most damaging pests of soybean (Glycine max (L.) Merr.). Host plant resistance has been the most effective control method. Because of the spread of multiple SCN races in Hokkaido, the Tokachi Agricultural Experiment Station has bred soybeans for SCN resistance since 1953 by using 2 main resistance resources PI84751 (resistant to races 1 and 3) and Gedenshirazu (resistant to race 3). In this study, we investigated the genetic relationships of SCN resistance originating from major SCN resistance genes in Gedenshirazu and PI84751 by using SSR markers. We confirmed that race 1 resistance in PI84751 was independently controlled by 4 genes, 2 of which were rhg1 and Rhg4. We classified the PI84751- type allele of Rhg1 as rhg1-s and the Gedenshirazu-type allele of Rhg1 as rhg1-g. In the cross of the Gedenshirazu-derived race 3-resistant lines and the PI84751-derived races 1- and 3-resistant lines, the presence of rhg1-s and Rhg4 was responsible for race 1-resistance. These results indicated that it was possible to select race 1 resistant plants by using marker-assisted selection for the rhg1-s and Rhg4 alleles through a PI84751 origin Gedenshirazu origin cross.
Hayashi Y.,Obihiro University of Agriculture and Veterinary Medicine |
Kozawa T.,Hokkaido Research Organization Tokachi Agricultural Experiment Station |
Aiuchi D.,Obihiro University of Agriculture and Veterinary Medicine |
Tani M.,Obihiro University of Agriculture and Veterinary Medicine |
Koike M.,Obihiro University of Agriculture and Veterinary Medicine
European Journal of Plant Pathology | Year: 2014
Winter wheat scab in Hokkaido, Japan is caused predominantly by Gibberella zeae and Microdochium nivale and can result in significant yield losses. A selective medium for isolation of G. zeae was previously developed, but not for M. nivale. The purpose of this study therefore was to develop a selective medium for isolation of airborne spores of M. nivale. Based on the basic composition of Komada's Fusarium-selective medium, carbon and nitrogen sources and the most suitable vitamin B component for the basal composition were examined. Hyphal growth of M. nivale was promoted when galactose was replaced with lactose and combined with L-asparagine, while aerial hyphal formation increased with thiamine hydrochloride as the vitamin B source. In antimicrobial composition, colony formation of other filamentous fungi was greatly inhibited by spiroxamine. Thiophanate methyl, to which M. nivale shows resistance, selectively inhibited the growth of Fusarium spp. only. Spore trapping using the selective medium was subsequently performed in a wheat field. M. nivale formed characteristic pinkish colonies on the selective medium in the case of contamination with other filamentous fungi, making differentiation easy. Overall, the findings show that LATTS medium developed in this study is effective for isolation of airborne spores of M. nivale. © 2013 KNPV.
Tanaka Y.,Hokkaido Research Organization Tokachi Agricultural Experiment Station |
Plant Production Science | Year: 2010
Days from full maturity to combine harvest maturity (DFC) is a major concern in combine harvesting of soybeans (Glycine max (L.)), especially in northern Japan, which has a short harvesting period. The combine harvest maturity, which was defined as the day at which the moisture content of the stem reached 30%, was analyzed using 7 soybean varieties for 3 yr in Hokkaido. There were significant differences in DFC among varieties (12 to 31 d) and among the 3 yr (16 to 25 d). DFC was closely associated with dry matter partitioning to stem (DMPS) at full maturity, that is, high DMPS increased DFC. The relationship between DMPS and DFC was examined by pod removal experiments conducted for 2 yr. In the soybean plants with high DMPS pod removal increased the stem desiccation period and DFC. These results indicated that DMPS at full maturity is an informative indicator for predicting the harvest maturity in the combine harvesting system.
PubMed | Chinese Academy of Sciences, Japan National Institute of Agrobiological Science, CAS Institute of Genetics and Developmental Biology, Hokkaido Research Organization Tokachi Agricultural Experiment Station and Hokkaido University
Type: Journal Article | Journal: Journal of experimental botany | Year: 2016
FLOWERING LOCUS T (FT) is an important floral integrator whose functions are conserved across plant species. In soybean, two orthologs, FT2a and FT5a, play a major role in initiating flowering. Their expression in response to different photoperiods is controlled by allelic combinations at the maturity loci E1 to E4, generating variation in flowering time among cultivars. We determined the molecular basis of a quantitative trait locus (QTL) for flowering time in linkage group J (Chromosome 16). Fine-mapping delimited the QTL to a genomic region of 107kb that harbors FT5a We detected 15 DNA polymorphisms between parents with the early-flowering (ef) and late-flowering (lf) alleles in the promoter region, an intron, and the 3 untranslated region of FT5a, although the FT5a coding regions were identical. Transcript abundance of FT5a was higher in near-isogenic lines for ef than in those for lf, suggesting that different transcriptional activities or mRNA stability caused the flowering time difference. Single-nucleotide polymorphism (SNP) calling from re-sequencing data for 439 cultivated and wild soybean accessions indicated that ef is a rare haplotype that is distinct from common haplotypes including lf The ef allele at FT5a may play an adaptive role at latitudes where early flowering is desirable.