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A chasmogamous mutant was induced by exposing a cleistogamous cultivar to sodium azide. The altered cly1 sequence in the mutant was not in the miR172 binding site, as is the case in other known cleistogamous alleles, but rather in a region encoding one of the gene product’s two AP2 domains. The genetic basis of cleistogamy (in which pollination occurs before the flower opens) in barley is centered on the Cleistogamy 1 locus (cly1). The sequence of the microRNA (miR172)-targeting site in the gene, which belongs to the APETALA2 family, differs between cleistogamous and chasmogamous cultivars at a single nucleotide position, resulting in the differential ability of the lodicules to swell. Here, mutagenesis of the barley cultivar ‘Misato Golden’ (which carries the cly1.b allele), achieved using sodium azide, was used to induce a change from cleistogamy to chasmogamy (non-cleistogamous flowering). The cly1 coding sequence in the selected mutant differed from that of cly1.b by two non-synonymous mutations, one of which was responsible for an altered residue in one of the AP2 domains present in the Cly1 protein. Although there was no difference in the miR172 targeting site between cly1.b and the novel allele (designated cly1.b3), the mutant’s lodicules’ ability to swell was indistinguishable from that observed in cultivars carrying the chasmogamous allele Cly1.a. The phenotype of cly1.b3/cly1.b, cly1.b3/cly1.b2 and cly1.b3/cly1.c heterozygotes indicated that cly1.b3 is recessive or incompletely dominant with respect to these alleles.

A chasmogamous mutant was induced by exposing a cleistogamous cultivar to sodium azide. The altered cly1 sequence in the mutant was not in the miR172 binding site, as is the case in other known cleistogamous alleles, but rather in a region encoding one of the gene product's two AP2 domains. The genetic basis of cleistogamy (in which pollination occurs before the flower opens) in barley is centered on the Cleistogamy 1 locus (cly1). The sequence of the microRNA (miR172)-targeting site in the gene, which belongs to the APETALA2 family, differs between cleistogamous and chasmogamous cultivars at a single nucleotide position, resulting in the differential ability of the lodicules to swell. Here, mutagenesis of the barley cultivar 'Misato Golden' (which carries the cly1.b allele), achieved using sodium azide, was used to induce a change from cleistogamy to chasmogamy (non-cleistogamous flowering). The cly1 coding sequence in the selected mutant differed from that of cly1.b by two non-synonymous mutations, one of which was responsible for an altered residue in one of the AP2 domains present in the Cly1 protein. Although there was no difference in the miR172 targeting site between cly1.b and the novel allele (designated cly1.b3), the mutant's lodicules' ability to swell was indistinguishable from that observed in cultivars carrying the chasmogamous allele Cly1.a. The phenotype of cly1.b3/cly1.b, cly1.b3/cly1.b2 and cly1.b3/cly1.c heterozygotes indicated that cly1.b3 is recessive or incompletely dominant with respect to these alleles.

Fusarium head blight (FHB) remains a serious problem that causes yield and grain quality losses, and mycotoxin accumulation in wheat production in western Japan. A 3-year field trial with artificial FHB inoculation was conducted to evaluate varietal characteristics of FHB resistance among 31 wheat cultivars/lines cultivated in western Japan, including one standard line. Severity of FHB, frequency of Fusarium-damaged kernels (FDK), deoxynivalenol concentration (DON), nivalenol concentration (NIV), and grain yield showed significant differences among years and among cultivars/lines. Interaction between years and cultivars/lines was also significant in these traits, but F values were larger for cultivars/lines than for the interaction. Correlation analysis showed that cultivars/lines with lower FHB severities tended to have lower FDK, DON and NIV, and a higher yield. Resistance to kernel infection (RKI), residuals calculated by regressing FDK against FHB severity, and resistance to mycotoxin accumulation (RTA), residuals calculated by regressing DON + NIV against FDK, also differed significantly among cultivars/lines. These results indicated that varietal differences in response to FHB symptom development, RKI and RTA exist among wheat cultivars/lines in western Japan. Such information is important to aid producers in controlling the disease and for breeders to improve FHB resistance and reduce mycotoxin accumulation in commercial wheat cultivars.

Forage barley (Hordeum vulgare L.) has attracted attention as a potential crop in Japan; however, promising cultivars and lines have not been selected and selection criteria for breeding have not been found. This study aimed to determine the effects of cultivars and lines (Wasedorinijyo, Saikaikawa 67, Saikaihadaka 68, Hakei B 0878, Hakei B 0879, and Nishinochikara) on dry matter (DM) yield and nutritive value in southwestern Japan. In the 2010–2011 crop season at heading and soft dough, Hakei B 0879 had similar DM yield to the other cultivars and lines used. However, in the 2011–2012 crop season, Hakei B 0879 had the highest number of tillers and the highest DM yield among all the cultivars and lines. The number of emerged seedlings of Hakei B 0879 was much higher in the 2011–2012 crop season than in the 2010–2011 crop season. Thus, in the 2010–2011 crop season at soft dough, the DM yield of Hakei B 0879 was reduced because of the lower number of tillers. To stabilize the DM yield of Hakei B 0879, improved seedling emergence and growth at early stages could be important. In both crop seasons at heading and soft dough, DM yield was positively correlated with the number of tillers and leaf plus stem dry weight (DW). In addition, in both crop seasons at heading, the in vitro dry matter digestibly (IVDMD) concentration of Saikaikawa 67 was higher than, or similar to, those of the other cultivars and lines used because of the lower neutral detergent fiber (NDF) concentration. These results suggest that spike-number type cultivars may be more suitable for forage barley than spike-weight type cultivars and the number of tillers could be a selection criteria for breeding.

Fusarium head blight (FHB), which is caused by Fusarium graminearum Schwabe [teleomorph: Gibberella zeae (Schwein.) Petch], is a devastating disease affecting wheat (Triticum aestivum L.) spikes, which considerably reduces grain yield and quality and produces mycotoxins that are harmful to humans and animals, especially in warm and humid climates, such as that of west Japan. Therefore, an important target of breeding programs is to improve FHB resistance in wheat. In general, wheat cultivars bred in west Japan exhibit high resistance to FHB worldwide. FHB resistance in wheat can be divided into resistance to initial infection (type I) and resistance to spread within the spike (type II). To improve FHB resistance in west Japanese wheat, we first improved the methods used to evaluate type I and II resistance separately. We then analyzed factors related to type I and II resistance using diverse materials. Finally, we selected a wheat line, ‘Norin PL-9,’ into which we integrated type I and II resistance, and applied for registration as the wheat parental line. The knowledge and materials developed in this study are useful for breeding FHB resistance in wheat where FHB outbreak is problematic. This review draws on a series of related studies.

Shiratae Nijo is a new two-rowed food barley cultivar bred at the National Agricultural Research Center for Kyushu Okinawa Region (KONARC) in collaboration with the National Institute of Crop Science (NICS) and released in 2009. Shiratae Nijo is a proanthocyanidin-free cultivar bred by backcross breeding using a leading cultivar Nishinohoshi as a recurrent parent and a foreign proanthocyanidin-free mutant ant28-494 as a non-recurrent parent. The agronomic characteristics of Shiratae Nijo are almost the same as those of Nishinohoshi which has high yield performance and high resistance to barley yellow mosaic virus (BaYMV) type I and powdery mildew. Like Nishinohoshi, Shiratae Nijo shows high resistance to Fusarium head blight (FHB) at the anthesis stage but is susceptible 10 days after anthesis. Shiratae Nijo exhibits significantly weaker seed dormancy than Nishinohoshi. Shiratae Nijo has excellent pearling quality, and the pearled grains show no discoloration and high whiteness after cooking because of the lack of catechin and proanthocyanidin in the grains.

ビールオオムギ初のオオムギ縞萎縮ウイルス（BaYMV）I，II，III型抵抗性新品種スカイゴールデンの普及にあたり，栃木県におけるBaYMV系統の発生を調査した．その結果，栃木県南地域ではIII型が常発化しており，県中北地域ではI型が発生していることから，これまで普及していた品種では不十分なことが明らかとなった．加えて，栃木県大田原市で既知のI，II，III型と病原性が異なり，BaYMV抵抗性遺伝子rym3を犯す大田原系統を見出した．この大田原系統と，同様にI，II，III型と病原性が異なり未同定であった山口系統について，罹病する品種の差異（病原性）および塩基やアミノ酸配列の相同性や系統樹による分子系統解析を用いて同定を試みた．その結果，それぞれI，II，III型と異なる系統で，大田原系統はIV型，山口系統はV型と判定された．IV型とV型の判別は，早木曽2号または浦項皮麦3と三月を判別品種として用いることにより可能である．また，スカイゴールデン，木石港3は，BaYMV I～V型のいずれにも抵抗性を示し，抵抗性育種に有効である．今後，ビールオオムギ品種育成において，BaYMV抵抗性遺伝子rym1，rym3，rym5の集積が重要と考えられる．

In wheat (Triticum aestivum L.), Fusarium head blight (FHB) resistance is an important breeding target to reduce yield losses and mycotoxin contamination. We hypothesized that cleistogamous (CL, closed flowering) cultivars have a lower risk of FHB infection than chasmogamous (CH, opened flowering) cultivars because FHB infection usually occurs in the inside of florets or extracted anthers and FHB resistance in CL cultivars decreases mycotoxin accumulation. To test these hypotheses, we produced 126 recombinant inbred lines (RILs) derived from a cross between common wheat varieties ‘U24’ (CL variety) and ‘Saikai 165’ (CH variety). Although ‘U24’ and ‘Saikai 165’ are both resistant to FHB infection, ‘U24’ is susceptible to FHB spread, grain deterioration, and mycotoxin accumulation compared with ‘Saikai 165’. Among the RILs, there were significant differences in all of the tested traits. Although the CL RILs showed less initial FHB infection than CH RILs, there were no significant differences in grain deterioration and mycotoxin accumulation between the 2 groups. An FHB-resistant quantitative trait locus (QTL) located on chromosome 3BS increased resistance to FHB spread, grain deterioration, and mycotoxin accumulation; however, not all CL RILs with this QTL accumulated less mycotoxin than ‘Saikai 165’.

黒ボク土など穀粒が高タンパク質化しやすい栽培環境における精麦品質の向上に有用な形質を明らかにするため，胚乳が粉状質を呈するモチ性および破砕デンプン粒変異（fractured starch granule）に関する準同質遺伝子系統を用いて，灰色低地土水田と黒ボク土畑における硝子率と精麦品質の差異を解析した．その結果，これらの準同質遺伝子系統ではタンパク質含量にかかわらず，ほぼ完全な粉状質であり，黒ボク土畑においても硝子質粒がほとんど発生しないことが明らかになった．また，モチ性および破砕デンプン粒変異の準同質遺伝子系統は，栽培土壌にかかわらず原系統よりも高白度であった．搗精時の砕粒発生は原系統と同程度かむしろ少なく，胚乳が粉状質であっても砕けやすい脆い粒質ではないことが明らかとなった．以上のことから，モチ性や破砕デンプン粒変異は，高タンパク質化の影響を受けない粉状質高白度品種の育成において有用な形質であると考えられた．また，これらの準同質遺伝子系統ではデンプン含量が減少したが，胚乳および糊粉層の細胞壁多糖であるβ–グルカンの含量が増加することが認められた．β–グルカンは，人体にとって種々の機能性を有する多糖であるため，モチ性や破砕デンプン粒変異は食用オオムギの付加価値の向上においても有用な形質であると考えられた．とくに，破砕デンプン粒変異はウルチ性の完全粉状質品種の育成に有用な形質であると考えられた．

Friction stir welding (FSW) has been receiving considerable attention along with friction stir processing (FSP), which is a new technique based on the principles of FSW. In a recent study by the author, the excellent fluidity of aluminum alloy in FSP was recognized, and metal matrix composites (MMCs) were fabricated by the local dispersion of aluminum oxide particulates in aluminum alloy. In the present study, we propose novel methods for property modification of MMCs, such as the fabrication of local metallic foam of 6061 aluminum alloy by FSP. First, titanium hydride particles (TiH2) were dispersed locally as a foaming material to produce the local MMC. Then, the specimen was heated in an electric oven for local foaming. As a result, the structure of the foam produced in the layers was controlled by the titanium hydride particles dispersed in those layers. By monitoring the heat generated during FSP, we investigated the possibilities of dispersing the foaming material by the heat generating in FSP without the application of additional heat using an electric oven. The result showed that the possibility of local foaming by the heat generated in FSP. However, there are still problems for solution like the control of the maximum heating temperature, and future tasks.

Fusarium head blight (FHB) is the most serious disease affecting wheat (Triticum aestivum L.) because of its impact on yield and grain quality and its associated mycotoxin accumulation. This study was conducted (1) to develop efficient methods to evaluate varietal resistance against fungal spread after infection, (2) to investigate varietal differences in resistance to FHB infection, FHB spread, and mycotoxin accumulation in 23 Asian varieties, and (3) to analyze relations among FHB-resistant types. Inoculation of Fusarium graminearum isolate, causing virulence to detached spikes, enabled evaluation of FHB spread in a shorter period and smaller space than conventional methods. Among the varieties, the FHB spread differed significantly. ‘Sumai 3’ and its derivatives showed higher resistance to FHB spread than other varieties. The FHB spread showed no significant correlation with FHB infection. It showed significant positive correlation with DON, but some varieties with high resistance to FHB spread showed moderately high DON. Results show that improved methods to evaluate FHB spread can be effective to screen numerous materials. The FHB resistance of western Japanese varieties depends mainly on resistance to FHB spread. For development of FHB resistant varieties, due attention should be devoted to DON.

Fungicide application is one measure available to reduce the risk of Fusarium head blight (FHB) and mycotoxin contamination in barley. The stage at or near anthesis, or at full head emergence, is generally thought to be optimal for fungicide application, regardless of cultivar. However, we have found that the most critical time for Fusarium graminearum infection and mycotoxin accumulation in barley differed among cultivars. Whereas open-flowering cultivars were most susceptible at anthesis, closed-flowering cultivars were considerably resistant at anthesis but became susceptible after ‘spent’ anther extrusion. Therefore, we evaluated the effect of the timing of fungicide application on FHB and mycotoxin (deoxynivalenol and nivalenol) accumulation in closed-flowering barley. Thiophanate-methyl fungicide was applied at different developmental stages, from before anthesis to 30 days after anthesis (DAA), under artificial inoculation conditions in the field in which inoculum spores were provided throughout the testing period. As expected, the optimal timing for chemical control of FHB and mycotoxin accumulation was the time around the beginning of spent anther extrusion, rather than at anthesis. Later application, as late as 30 DAA, was also effective in controlling mycotoxin accumulation, although it was not effective in controlling disease levels. Our results suggest that the development of control strategies that cover the late stage as well as the early stage is desirable to reduce the risk of mycotoxin contamination in barley.

A (1→3),(1→4)-β-glucan synthase catalysing the synthesis of (1→3),(1→4)-β-glucan (mixed-linkage glucan) was investigated using microsomal membranes prepared from developing barley (Hordeum vulgare L. cv. Shikokuhadaka 97) endosperms harvested 21 days after flowering. The microsomal fraction produced (1 →3),(1→4)-β-glucan by incorporation of [ 14 C]Glc from UDA-[ 14 C]Glc. The production of (1→3),(1→4)-β-glucan was ascertained by specific enzymatic digestion with endo-(1→3),(1→4)-β-glucanase (lichenase; EC 3.2.1.73) from Bacillus amyloliquefaciens, which released a radiolabelled trisaccharide (3-O-β-cellobiosyl-glucose) and a tetrasaccharide (3-O-β-cellotriosyl-glucose), the diagnostic oligosaccharides for the identification of (1→3), (1→4)-β-glucan. Digestion of the products with exo-(1→3)-β-glucanase (EC 3.2.1.58) from Basidiomycete QM806 released radiolabelled Glc, indicating that not only (1 →3),(1→4)-β-glucans but also (1 →3)-β-glucans (callose) had been formed due to the presence of (1→3)-β-glucan (callose) synthase (EC 2.4.1.34) in the microsomal fraction. The activity of (1→3),(1→4)-P-glucan synthase was maximal at pH 9.0 and at 25°C and in the presence of at least 2 mM Mg 2- . The apparent K m and V max values for UDP-Glc were 0.33 mM and 480 pmol min -1 mg protein -1 , respectively. Investigating the dependence of enzyme activity on developmental stage (7-35 days after flowering) of the endosperms, we found an increase of activity during the initial development reaching a maximum at 19 days, followed by a gradual decrease as the endosperms matured. The amount of (1→3),(1→4)-β-glucan in the cell walls of the endosperms, however, increased gradually towards maturation, even after 19 days. Analysing the relationship between enzyme activity and (1 →3),(1→4)-β-glucan deposition in cell walls of endosperms prepared from 12 different barley varieties harvested 11-22 days after flowering showed that some varieties had both low activity and low glucan content, and in some both were high. But for several other varieties, the availability of donor substrate and other factors seem to influence the production of (1→3),(1-4)-P-glucan as well.

Fusarium head blight (FHB) is a destructive disease of barley. The genetics and expression of resistance to FHB in barley is complex, and various spike characters are thought to possibly influence resistance. Tests using spray-inoculation of Fusarium graminearum at anthesis in greenhouse environments showed that two-rowed and cleistogamous varieties from Japan belong to the highest resistance group, while six-rowed and chasmogamous varieties are mostly susceptible. In order to evaluate the effect of such spike characters, including row type and flowering type, on FHB resistance, near-isogenic lines (NILs) differing in these characters were tested for their resistance. Two testing methods were used: the ‘pot-plant’ and ‘cut-spike’ methods, in which spikes at anthesis were spray-inoculated in greenhouse environments. The chasmogamous NILs and some six-rowed NILs were significantly more diseased than cleistogamous and two-rowed parent lines, respectively, and the difference in FHB severity was greater and more stable between cleistogamous/chasmogamous NIL pairs than between two-/six-rowed pairs. Slight or no differences were observed in glaucous/non-glaucous, normal/dense spike, normal/uzu type and normal/deficiens NIL pairs. The results indicate that the contribution of cleistogamy and/or the genetic background toward FHB resistance is more than that of row type and the other tested spike characters. Further, it should be possible to develop six-rowed varieties with FHB resistance nearly as good as that of the two-rowed varieties.

A β-(1→4)-xylosyltransferase (XylTase; EC 2.4.2.24) participating in the synthesis of arabinoxylans was investigated using microsomal membranes prepared from developing barley (Hordeum valgare L.) endosperms. The microsomal fraction transferred Xyl from uridine 5'-diphosphoxylose (UDP-Xyl) into exogenous β-(1→4)-xylooligosaccharides derivatized at their reducing ends with 2-aminopyridine. HPLC analysis showed chain elongation of pyridylaminated β-(1→4)-xylotriose (Xyl 3 -PA) by repeated attachment of one to five single xylosyl residues depending on the reaction time, leading to the formation of Xyl 4-8 -PA. Methylation analysis and enzymatic digestions with βxylosidase (EC 3.2.1.37) and emdo-β-(1→4)-xylanase (EC 3.2.1.8) confirmed that the transfer of xylosyl residues into the newly synthesized products occurred through β-(1→4)-linkages. The activity of the XylTase was maximal at pH 6.8 and 20°C and most enhanced in the presence of 0.5% Triton X-100 and 5 mM MnCl 2 . The apparent Michaelis constant and maximal velocity of the enzyme for Xyl 3 -PA were 2.1 mM and 25400 pmol min -1 mg protein -1 , respectively. The enzyme also transferred [ 14 C]Xyl from UDP-[ 14 C]Xyl into higher β-(1→4)-xylooligosaccharides and birchwood xylans through β-(1→4)-linkages. The enzyme activity varied according to the stage of development (7-35 days after flowering) of the endosperms. Maximal activity occurred at 13-16 days; no activity was detectable in mature seeds. A comparison of endosperms from 10 different cultivars of barley harvested 11-22 days after flowering showed no correlation between enzyme activity and the amount of Xyl in the cell walls.

SummaryThe msm 1 and msm 2 cytoplasms cause male sterility in barley. In order to clarify whether these cytoplasms can be used for hybrid seed production in Japan, we investigated the fertility restoration under environmental conditions in Japan using alloplasmic lines and an isogenic line. Fertility of barley lines containing msm1 and msm2 was completely restored by the restorer gene Rfm 1a. The effect of cytoplasm on malting quality was also investigated, but no significant difference in malting quality was observed between lines possessing msm1, msm2, and original cytoplasms. Malting quality also did not differ between Rfm1a/Rfm1a and Rfm1a/rfm1a genotypes, suggesting that Rfm1a and its flanking genes are not associated with heterosis for malting quality. Possibilities of hybrid barley breeding using these male sterile cytoplasms are discussed.

Efficiency of solar energy utilizatiion (Eu, %), efficiency of solar energy conversion (Ec, %) and conversion efficiency were determined for two-rowed barley (cv. Nishinochikara) plant grown in warm regions in Japan. Absorbed solar radiation during the stage from internode elongation to heading was about 56% of the total supplied solar radiation, and that in the ripening stage was about 70%. Absorbed solar radiation (SRα) in the growing period was 865.02 MJ m-2, equivalent to about 40% of the total solar radiation. Ec at the internode elongation to heading stage was 3.94%. Eu and Ec were 1.47% and 2.13% in the ripening period, both of which accounted for 1.09% and 2.71% in the whole growing period, respectively. These values were equal to those of rice grown in the same regions in Japan. Top dry weight was variable in proportion to SRα, and Cs (Conversion efficiency) was 2.32g MJ-1, The value of Cs determined in the early and middle ripening stages were 1.79g MJ-1 and 1.17g MJ-1, respectively.

Cultivar difference on dry matter production and grain production in two-rowed barley (Hordeum distichum L. emend, LAMARK) of warm regions in Japan were investigated from 1987 to 1989. Fifteen Japanese cultivars and nineteen foreign cultivars in 1987/1988, and four Japanese cultivars and eleven foreign cultivars in 1988/1989 were grown under field conditions. The full heading stage of Japanese cultivars except New Golden and Kanto Nijyo 19 in 1987/1988 was in the early of April, but the foreign cultivars except WI-2727 was in the late of April. The top dry weight of Japanese cultivars was 615-1001 g m-2, and that of the foreign cultivars was 744∼1088 g m-2. The top dry weight of late maturing cultivars in the full heading stage was higher than that of early and middle maturing cultivars. The LAI of Japanese cultivars was 3∼4, and Nishinochikara was 4.97, higher than the early maturing cultivars. The maturing stage of Japanese cultivars except New Golden, Daisen Gold and Kanto Nijyo 19 was in the middle of May. The grain weight were 408∼544 g m-2. The harvest index (HI) of breeding cultivars in Japan in recent years was 41∼42 and that of Hakei 86-107 was 46.1.

Cultivar differences of effeciency of solar energy utilization (Eu) and efficiency of solar energy utilization in grain (Eu grain) in two-rowed barley (34 cultivars) were investigated from 1987 to 1988. The relationship between accumulated solar radiation and top dry weight at the vegetative stage from the sowing date to full heading stage was proportional (r=0.875***). Eu in Japanese cultivars was less than 1.0%, but Eu of Koru, Bomi, Kym and Menuet in foreign cultivars was higher than 1.0%. Eu of Kawa Saigoku, Kanto Nijo 19 and WI-2585 at the ripening stage were 1.303%, 1.328% and 1.340%, respectively, but other Japanese cultivars were 0.8∼1.2%. Eu of Keg, Koru, Bomiand Kanto Nijo 19 at maturity was higher than 1.1%. Eu grain in Miho Golden, Kawamizuki, Ishukushirazu, Nishinochikara, Saikai Kawa 43, Hakei 86-107, Hakei 87-39, WI-2727, Bomi, Kym, Ida and Flare was higher than 0.40%.

Flavonoids accumulated in proanthocyanidin-free near-isogenic lines iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi, developed by backcross breeding using a leading cultivar, Nishinohoshi, as a recurrent parent and a proanthocyanidin-free mutant as a nonrecurrent parent in Japan, were examined. A new flavanone, (2RS)-dihydrotricin 7-O-β-D-glucopyranoside (1), known flavanones (2RS)-dihydrotricin (2) and (2RS)-homoeriodictyol (3), and known flavones chrysoeriol 7-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside] (4), chrysoeriol 7-O-β-D-glucopyranoside (5), tricin (6), and chrysoeriol (7) were isolated from iso ant 17 of Nishinohoshi. The structures and stereochemistries of the isolated flavonoids (1-7) were elucidated on the basis of spectroscopic analyses. The concentrations of the isolated flavonoids (1-7) in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi were similar to each other, whereas the flavonoids 1-5 and 7 were not detected in Nishinohoshi, an old Japanese cultivar, Amaginijo, and North American cultivar Harrington. The concentration of tricin (6) in Nishinohoshi was a half those in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi. Except for iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi, the concentration of tricin (6) was highest in Nishinohoshi, followed by Amaginijo and Harrington. Thus, tricin (6), its precursor dihydrotricin (2), and its glucopyranoside, dihydrotricin 7-O-β-D-glucopyranoside (1), as well as chrysoeriol (7) and homoeriodictyol (3) were accumulated in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi probably by blocking at the step of flavanone 3-hydroxylase in the procyanidin biogenetic pathway, resulting in enhancement of the alternative biogenetic pathway.

For breeding early heading wheat cultivars with resistance to frost damage which are well adapted to dry areas of West Asia and North Africa, the relationships between winter hardiness, ear primordia development and heading traits, i.e. veernalization requirement, photoperiodic response and narrow-sense earliness, were assessed using a total of 30 genotypes of wheat (Triticum aestivum L.) grown in an experiment in Syria. The results of artificial freezing tests indicated that cultivars with good winter hardiness were to be found only in the winter wheat cultivars which required 50 or more days of vernalization treatment. These winter wheat cultivars did not initiate internode elongation without vernalization even at 95 days after planting. Thus their ear primordia were still underground and were protected from frost injury at this stage. Photoperiodic response and narrow-sense earliness were not associated with winter hardiness and earliness of internode elongation, but were related to the number of days to heading after planting. This indicated the possibility for breeding early heading cultivars with winter hardiness and tiller frost avoidance by combining high vernalization requirement, short narrow-sense earliness and neutral response to photoperiod.

Barley has two flowering types, chasmogamous (open-flowering) and cleistogamous (closed-flowering). We examined the effect of the timing of Fusarium graminearum infection on Fusarium head blight (FHB) and mycotoxin accumulation in barley cultivars with different flowering types using greenhouse experiments. In the first experiment, 13 cultivars were spray inoculated at two different developmental stages, and the severity of FHB was evaluated. The effect of the timing of infection differed among cultivars. Cleistogamous cultivars were resistant at anthesis but susceptible at 10 days after anthesis, whereas chasmogamous cultivars were already susceptible at anthesis. In the second experiment, five cultivars were inoculated at three different developmental stages and the concentrations of deoxynivalenol (DON) and nivalenol (NIV) in mature grain were analyzed. Cleistogamous cultivars accumulated more mycotoxins (DON and NIV) when inoculated 10 or 20 days after anthesis than when inoculated at anthesis, whereas chasmogamous cultivars accumulated more mycotoxins when inoculated at anthesis. Thus, the most critical time for F. graminearum infection and mycotoxin accumulation in barley differs with cultivar, and likely is associated with the flowering type. Late infection, even without accompanied FHB symptoms, was also significant in terms of the risk of mycotoxin contamination.

A Chinese landrace of six-rowed barley, Mokusekko 3, has been successfully utllized for introducing its BaYMV resistant gene, Ym, to Japanese malting two-rowed barley. However, information about the location of the Ym locus on a chromosome is limited. The authors almed to confirm the linkage relationship between the Ym locus and complex loci for esterase isozymes, as most of the strains into which the BaYMV resistance from Mokusekko 3 had been introduced showed the same esterase isozyme banding pattern as that of the resistant parent. The linkage analyses revealed that the Ym locus is tightly linked with the complex loci (Est1-Est2-Est4) for the esterase isozymes which are located at the terminal of the long arm of chromosome 3, and that the recombination values ranged from 1.26 to 5.01%. Based on these results, it is concluded that the BaYMV resistant individuals and strains carrying the Ym gene can be easily obtained by selecting the seedlings which show the same banding pattern of esterase isozyme genotype as that of Mokusekko 3, by means of starch gel electrophoresis.