Spatial kernel models capturing field heterogeneity for accurate estimation of genetic potential     

Motoyuki Ishimori  Hideki Takanashi  Masaru Fujimoto  Hiromi Kajiya-Kanegae  Junichi Yoneda  Tsuyoshi Tokunaga  Nobuhiro Tsutsumi  Hiroyoshi Iwata 《Breeding Science》2021,71(4):444

According to Fisher’s principles, an experimental field is typically divided into multiple blocks for local control. Although homogeneity is supposed within a block, this assumption may not be practical for large blocks, such as those including hundreds of plots. In line evaluation trials, which are essential in plant breeding, field heterogeneity must be carefully treated, because it can cause bias in the estimation of genetic potential. To more accurately estimate genotypic values in a large field trial, we developed spatial kernel models incorporating genome-wide markers, which consider continuous heterogeneity within a block and over the field. In the simulation study, the spatial kernel models were robust under various conditions. Although heritability, spatial autocorrelation range, replication number, and missing plots directly affected the estimation accuracy of genotypic values, the spatial kernel models always showed superior performance over the classical block model. We also employed these spatial kernel models for quantitative trait locus mapping. Finally, using field experimental data of bioenergy sorghum lines, we validated the performance of the spatial kernel models. The results suggested that a spatial kernel model is effective for evaluating the genetic potential of lines in a heterogeneous field.  相似文献   

Estimating a suitable microsatellite marker set for individual identification and parentage tests of brown bear (Ursus arctos) in the Akan–Shiranuka Region, eastern Hokkaido, Japan     

Tetsuji Itoh  Yoshikazu Sato  Tsutomu Mano  Ryûtarô Iwata 《Journal of Forest Research》2009,14(2):117-122

We examined 24 microsatellite markers to select those most suitable for individual identification and parentage tests of brown bears (Ursus arctos) based on statistical parameters and experimental error using liver samples (38 issues) from nuisance bears killed in the Akan–Shiranuka Region, eastern Hokkaido, Japan from 1996 to 2006. We found seven microsatellite markers suitable for identifying individuals (G1A, G10B, G10L, UarMU5, UarMU23, UarMU50, and UarMU51; probability of identity P _id = 3.17  × 10⁻⁷; probability of identity of sibs P _id-sib  = 2.23 × 10⁻³), 12 microsatellite markers suitable for parentage testing when one parent is known [G1A, G1D, G10B, G10L, G10P, UarMU5, UarMU23, UarMU50, UarMU51, UarMU59, UarMU61, and UarMU64; probability of excluding one parent (PE I = 0.9991)], and 15 microsatellite markers for parentage testing when neither parents are known [three markers added to the above: G10M, G10X, and UarMU9; probability of excluding both parents (PE II = 0.9869)].  相似文献   

Genetic diversity and expression of carbon monoxide dehydrogenase from <Emphasis Type="Italic">Aeropyrum pernix</Emphasis>     

Hiroshi Nishimura  Nozomi Sato  Yoshiko Nomura  Eri Iwata  Yoshihiko Sako 《Fisheries Science》2011,77(1):135-141

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Boring activity on coniferous tree branches byXylotrechus villioni (Villard) larvae (Coleoptera: Cerambycidae)     

Ryûtarô Iwata  Yoichi Sakakibara  Fusao Yamada 《Journal of Forest Research》1998,3(4):247-249

In anAbies homolepis Sieb. et Zucc. forest at Matsumoto, Nagano Pref., cumulative damage byXylotrechus villioni (Villard) (Coleoptera: Cerambycidae) was observed on tree branches. Of the 14 major branches in one sample tree, six had cumulative damage by boring larvae, of which 3 had been bored by multiple larvae. No adult emergence holes were found on the whole tree, suggesting very low survivorship from boring larva to emerging adult. Galleries made by single larvae were often observed to be terminated by a depression apparently carved by a picid woodpecker, suggesting that they are important predators of the cerambycid. The manner of cicatrix formation with phloem tissue over the larval gallery in anAbies veitchii Lindl. branch at Mt. Fuji, Yamanashi Pref. is presented. Studies onXylotrechus villioni (Villard) (Coleoptera: Cerambycidae), a primary borer of coniferous trees in Japan (III). This work was presented at the 104th Annual Meeting of Japanese Forestry Society at Morioka (April, 1993) and 20th International Congress of Entomology at Firenze (August, 1996). This work is supported by a Grant-in-Aid for Scientific Research (No.02660163) from the Ministry of Education, Science, Sports, and Culture of Japan.  相似文献   

Performances of four chemicals with floral scents as attractants for longicorn beetles (Coleoptera: Cerambycidae) in a broadleaved forest     

Yoichi Sakakibara  Akira Kikuma  Ryûtarô Iwata  Akiomi Yamane 《Journal of Forest Research》1998,3(4):221-224

White plastic insect traps (manufactured by Sankei Chemical Co., Ltd.) equipped with four chemicals with floral scents, namely, benzyl acetate, methyl benzoate, methyl phenylacetate and linalool, were set from June 28 to August 9, 1996. The traps were placed in a Japanese beech (Fagus creata) forest, Minakami, Gunma Prefecture, Central Japan, and trapped longicorn beetles were collected weekly. The greatest number of species and individuals belonged to the subfamily Lepturinae dominated by the genusPidonia. No significant differences were observed in the performances of the above four chemicals in either the total number of species or of individuals. However, more Lamiinae species were captured in the traps with methyl phenylacetate, than in those with methyl benzoate. A part of this paper was presented at the 48th Meeting of the Kanto Branch of the Jpn. For. Soc. (1996).  相似文献   

Social rank modulates brain arginine vasotocin immunoreactivity in false clown anemonefish (<Emphasis Type="Italic">Amphiprion ocellaris</Emphasis>)     

Eri Iwata  Yukiko Nagai  Hideaki Sasaki 《Fish physiology and biochemistry》2010,36(3):337-345

The brain nanopeptide arginine vasotocin (AVT) and its mammalian homolog arginine vasopressin are involved in the regulation of social and reproductive behavior. We investigated the relationship between social rank formation and the brain AVT system in the false clown anemonefish (Amphiprion ocellaris), which forms a social rank that leads to sex differentiation in higher-ranked individuals. Tanks of three sexually immature fish were kept for 90 days and each fish’s behavior was observed once a month. The social rank of each individual was distinguishable by behavior, but gonadosomatic index (GSI) did not differ significantly. The number of AVT neurons in the magnocellular layer in the preoptic area (POA) increased in subordinate individuals and declined with increasing hierarchical dominance. These results suggest that social rank formation modulates AVT production in the brain of the clown anemonefish and may influence their later sex differentiation.  相似文献   

Contribution of toxicologic pathologists for the safety of human health in biomedical research—past,present, and future of the JSTP     

Makoto Enomoto  Hijiri Iwata  Mari Iida 《Journal of toxicologic pathology》2021,34(4):275

The research field of “Toxicologic Pathology” evaluates potentially toxic chemical exposures and chemically mediated illnesses in humans and experimental animals. Comparative studies of chemical exposures between model organisms and humans are essential for the risk assessment of chemicals and human health. Here we review the development and activities of the Japanese Society of Toxicologic Pathology (JSTP) during its 37-year history. Toxicological pathology studies provide many interesting and valuable findings. Rodent cancer bioassay data demonstrate the importance of dose levels, times, and duration of exposures to chemicals that possibly cause human cancers. Studies of toxic injuries in the nasal cavity demonstrate that specific chemical compounds affect different target cells and tissues. These observations are relevant for current air pollution studies in the preventive medicine field. Future toxicological pathology studies will be enhanced by applying molecular pathology with advanced observation techniques. In addition to the nasal cavity, another sense organ such as the tongue should be a potential next program of our mission for risk assessment of inhaled and ingested chemicals. As a message to the younger members of the JSTP, interdisciplinary and global cooperation should be emphasized. Elucidating the mechanisms of toxicologic pathology with a combination of advanced expertise in genetics and molecular biology offers promise for future advances by JSTP members.  相似文献   

Method of lymphocytotoxic crossmatch test for feline renal transplantation.   总被引：1，自引：0，他引：1  

Y Kuwahara  R Kobayashi  J Iwata  K Kitoh  H Kitagawa  Y Sasaki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(5):481-485

The optimal condition for methods of lymphocytotoxic crossmatch test for feline renal transplantation was investigated. On separation of viable lymphocytes from whole blood, the best results were obtained when Ficoll-diatrizoate with 1.078 of a specific gravity at 20 degrees C was centrifuged with 800 x g for 30 min at 4 degrees C. A nylon wool column was used to separate T and B cells from lymphocyte fraction. The ratio of T cells in nylon wool effluent cells was 95%, while the ratio of B cells in adherent cells was 41%. Lymphocytotoxic crossmatch tests were performed by using the effluent cells as T cells and the adherent cells as B cells, at 37 degrees C (warm) and 4 degrees C (cold). The ratio of B cells in adherent cells was low, however, the result was utilized as a matching test before transplantation by combining with the T cell result. The trypan blue stain method made it easier than the eosin stain method to distinguish living and dead cells. The lymphocytotoxic crossmatch tests were performed on 15 pairs of healthy cats, and only one pair showed doubtful positive against anti-B cell cold antibodies. During acute rejection after renal transplantation in two pairs which were negative on any anti-lymphocyte antibodies before the transplantation, the anti-T cell warm antibodies became positive in both pairs, and the anti-T cell cold antibodies became positive on one of the two pairs.  相似文献   

Osmoregulatory ability of chum salmon,Oncorhynchus keta,reared in fresh water for prolonged periods     

Ms. S. Hasegawa  T. Hirano  T. Ogasawara  M. Iwata  T. Akiyama  S. Arai 《Fish physiology and biochemistry》1987,4(2):101-110

The osmoregulatory ability of chum salmon (Oncorhynchus keta), reared in fresh water for a prolonged period, was examined by transferring them directly to seawater and then back to fresh water. When fry and juveniles weighing 0.3–125g, reared in fresh water for 1.5–13 months, were transferred directly to seawater, they adjusted their plasma Na⁺ concentration to the seawater-adapted level within 12–24h. When they were transferred back to fresh water after having been adapted to seawater for 2 weeks, the plasma Na⁺ level gradually decreased during the first 12–24h, and then increased to reattain the initial freshwater level after 5–7 days. No mortality was observed during the experiment except among the smallest fry weighing about 0.3g after transfer to seawater (2.1%). The maintenance of good osmoregulatory ability of the chum salmon for a prolonged period in fresh water seems to be unique among Pacific salmon, with the possible exception of the pink salmon.Changes in plasma levels of hormones during the transfer experiments were recorded in juveniles reared in fresh water for 13 months. Prolactin levels increased maximally 3 days after transfer from seawater to fresh water, as would be expected from its well-established role in freshwater adaptation in several euryhaline teleosts. In addition, an increase in plasma growth hormone was observed during the first 12h after seawater transfer, along with a tendency towards a decrease during freshwater transfer, suggesting an important role for this hormone in seawater adaptation. There were no consistent changes in plasma levels of thyroxine and cortisol during freshwater to seawater or seawater to freshwater transfer.  相似文献   

Genomics-assisted breeding in fruit trees     

Hiroyoshi Iwata  Mai F. Minamikawa  Hiromi Kajiya-Kanegae  Motoyuki Ishimori  Takeshi Hayashi 《Breeding Science》2016,66(1):100-115

Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding.  相似文献