Regulation of Seed Dormancy Genes in Triticeae Species.

Wild progenitors of Triticeae crops generally have long dormancy periods. Domesticated crops inherited these longer dormancy alleles from their wild progenitors, which have since been modified and selected during cultivation and utilization by humans. Thus, allelic combinations at different seed dormancy loci are currently represented in Triticeae germplasm preserved in seed repositories and gene banks as accessions and materials of breeding programs. Methods to evaluate seed dormancy are key to explore, analyze, and exploit optimal alleles in dormancy genes. Recent developments in genomics have accelerated the identification and analysis of seed dormancy loci in Triticeae species. Transgenic experiments have been conducted to validate if candidate genes affect seed dormancy and more recently have yielded an array of mutations derived from genome editing for practical applications. The information gathered on these seed dormancy loci provides a deeper knowledge of germplasm diversity and offers strategies to control seed dormancy in breeding programs in Triticeae crops.

Evaluation Methods for Preharvest Sprouting Resistance in Japanese Wheat Breeding Programs.

Different methodologies have been applied for the selection of preharvest sprouting resistance in cereal breeding programs. We describe here a series of methods used in practical wheat breeding programs in Japan, including phenotyping based on germination score after artificial rain treatments and genotyping using DNA markers. These methods can be modified and applied to breeding programs in which preharvest sprouting is a problem during cereal cultivation.

Evolution of wheat blast resistance gene Rmg8 accompanied by differentiation of variants recognizing the powdery mildew fungus.

Wheat blast, a devastating disease having spread recently from South America to Asia and Africa, is caused by Pyricularia oryzae (synonym of Magnaporthe oryzae) pathotype Triticum, which first emerged in Brazil in 1985. Rmg8 and Rmg7, genes for resistance to wheat blast found in common wheat and tetraploid wheat, respectively, recognize the same avirulence gene, AVR-Rmg8. Here we show that an ancestral resistance gene, which had obtained an ability to recognize AVR-Rmg8 before the differentiation of Triticum and Aegilops, has expanded its target pathogens. Molecular cloning revealed that Rmg7 was an allele of Pm4, a gene for resistance to wheat powdery mildew on 2AL, whereas Rmg8 was its homoeologue on 2BL ineffective against wheat powdery mildew. Rmg8 variants with the ability to recognize AVR-Rmg8 were distributed not only in Triticum spp. but also in Aegilops speltoides, Aegilops umbellulata and Aegilops comosa. This result suggests that the origin of resistance gene(s) recognizing AVR-Rmg8 dates back to the time before differentiation of A, B, S, U and M genomes, that is, ~5 Myr before the emergence of its current target, the wheat blast fungus. Phylogenetic analyses suggested that, in the evolutionary process thereafter, some of their variants gained the ability to recognize the wheat powdery mildew fungus and evolved into genes controlling dual resistance to wheat powdery mildew and wheat blast.

Breeding of a Near-Isogenic Wheat Line Resistant to Wheat Blast at Both Seedling and Heading Stages Through Incorporation of Rmg8.

Wheat blast caused by Pyricularia oryzae pathotype Triticum (MoT) has been transmitted from South America to Bangladesh and Zambia and is now spreading in these countries. To prepare against its further spread to Asian countries, we introduced Rmg8, a gene for resistance to wheat blast, into a Japanese elite cultivar, Chikugoizumi (ChI), through recurrent backcrosses and established ChI near-isogenic lines, #2-1-10 with the Rmg8/Rmg8 genotype and #4-2-10 with the rmg8/rmg8 genotype. A molecular analysis suggested that at least 96.6% of the #2-1-10 genome was derived from the recurrent parent ChI. The #2-1-10 line was resistant to MoT not only in primary leaves at the seedling stage but also in spikes and flag leaves at the heading stage. The strength of the resistance in spikes of this Rmg8 carrier was comparable to that of a carrier of the 2NS segment, which has been the only genetic resource released to farmers' fields for wheat blast resistance. On the other hand, the 2NS resistance was not expressed on leaves at the seedling stage nor flag leaves at the heading stage. Considering that leaf blast has been increasingly reported and regarded as an important inoculum source for spike blast, Rmg8 expressed at both the seedling and heading stages, or more strictly in both leaves and spikes, is suggested to be useful to prevent the spread of MoT in Asia and Africa.

Pharmacotherapy in Patients with Alzheimer-type Dementia Presenting with Behavioral and Psychological Symptoms of Dementia: A Retrospective Chart Review of 102 Patients Available for 12-month Follow-up after Initiation of Treatment.

Objectives: Alongside non-pharmacological intervention, pharmacotherapy particularly with atypical antipsychotics is assumed to be effective for behavioral and psychological symptoms of dementia (BPSD). Methods: This retrospective study investigated the effectiveness and safety of pharmacotherapy including antipsychotics in outpatients or inpatients with BPSD. Results: Of all Alzheimer-type dementia (AD) patients with BPSD initiating treatment between March and August 2011, a total of 102 patients available for 12-month follow-up comprised the subjects in this chart review. Of these, 68 (66.7%) continued treatment in the ambulatory or inpatient setting, with their MMSE scores improved from 17.3 ± 3.6 at baseline to 18.3 ± 3.53, 17.9 ± 3.80 and 17.0 ± 4.14 after 3, 6 and 12 months, respectively. In contrast, their NPI scores were significantly different from 11.7 ± 11.2 at baseline to 4.86 ± 5.40, 3.56 ± 4.65 and 2.27 ± 3.77 after 3, 6 and 12 months, respectively. Of the 36 inpatients available for follow-up, 27 (75%) on concurrent antipsychotics (chlorpromazine [CP] equivalent, 162.2 mg) at baseline remained on concurrent antipsychotics (CP equivalent, 212.5 mg) after 12 months, while, of the 66 outpatients available for follow-up, 13 (19.7%) on concurrent antipsychotics (CP equivalent, 93.4 mg) at baseline remained on concurrent antipsychotics (CP equivalent, 113.0 mg) after 12 months. Conclusions: Study results confirmed the effectiveness and safety of the study treatment in Japanese AD patients with BPSD for up to 12 months. How best to incorporate antipsychotics into the treatment of BPSD in clinical settings lies in the hands of us Japanese clinicians.