Identification of quantitative trait loci for flowering-related traits in the D genome of synthetic hexaploid wheat lines

The gene pool of Aegilops tauschii, the D-genome donor of common wheat (Triticum aestivum L.), can be easily accessed in wheat breeding, but remains largely unexplored. In our previous studies, many synthetic hexaploid wheat lines were produced through interspecific crosses between the tetraploid wheat cultivar Langdon and various A. tauschii accessions. The synthetic hexaploid wheat lines showed wide variation in many characteristics. To elucidate the genetic basis of variation in flowering-related traits, we analyzed quantitative trait loci (QTL) affecting time to heading, flowering and maturity, and the grain-filling period using four different F₂ populations of synthetic hexaploid wheat lines. In total, 10 QTLs located on six D-genome chromosomes (all except 4D) were detected for the analyzed traits. The QTL on 1DL controlling heading time appeared to correspond to a flowering time QTL, previously considered to be an ortholog of Eps-A ^m 1 which is related to the narrow-sense earliness in einkorn wheat. The 5D QTL for heading time might be a novel locus associated with wheat flowering, while the 2DS QTL appears to be an allelic variant of the photoperiod response locus Ppd-D1. Some of the identified QTLs seemed to be novel loci regulating wheat flowering and maturation, including a QTL controlling the grain filling period on chromosome 3D. The exercise demonstrates that synthetic wheat lines can be useful for the identification of new, agriculturally important loci that can be transferred to, and used for the modification of flowering and grain maturation in hexaploid wheat.     

Changes in the diet of a recovering Eurasian otter population between the 1970s and 2010

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Radial variations in the anatomical characteristics and density of the wood of Acacia mangium of five different provenances in Indonesia

The anatomical characteristics and density of wood were examined in 23-year-old Acacia mangium trees that had been planted in Yogyakarta, Indonesia. The seeds had been collected from trees of five different provenances. The distance from the pith of the boundary between juvenile and mature wood was also examined to clarify the maturity of the wood. Lengths of wood fibers near the pith and the distance from the pith of the boundary between juvenile and mature wood differed significantly among provenances. By contrast, other anatomical characteristics of the wood such as fiber wall area, fiber wall thickness, fiber diameter, vessel lumen area, vessel diameter, vessel frequency and wood density did not differ significantly among provenances. Wood density was strongly correlated with the area of fiber walls. Our observations suggest that Sidei and Daintree might be more appropriate provenances among those examined for the Acacia mangium tree-breeding programs in Indonesia that are aimed at improving wood quality, because these provenances are associated with longer initial wood fibers and narrower juvenile areas than the other provenances studied.     

Establishment of a pair of novel cloned tumour cell lines with or without metastatic potential from canine mammary adenocarcinoma

We produced 23 cloned cell lines from parental CHMp, which was previously established from a canine mammary adenocarcinoma patient in our laboratory. Two representative cloned cell lines, namely, CHMp-5b and -13a, were selected and characterized for cellular morphology, growth potential and expression of some tumour-related proteins. Subsequently, we transplanted the 2 tumour cell lines orthotopically into female nude mice to examine their tumorigenicity and metastatic potential. Interestingly, despite sharing the same origin, only CHMp-5b cells metastasized to the lung. Our results indicate that a comparison between these 2 cell lines at the molecular level will help us understand mechanisms of tumour progression, especially in the context of distant metastases originating from canine mammary gland tumours.     

Effects of substance P on fluid and amylase secretion in exocrine pancreas of rat and mouse

The effects of substance P on fluid and amylase secretion were examined in the exocrine pancreas of the rat and the mouse in vivo and in vitro. In the anaesthetised rat, a single intravenous injection of substance P caused an atropine resistant increase in both the basal and caerulein stimulated flow of pancreatic juice and amylase output, but reduced the secretin stimulated pancreatic juice flow. In vitro experiments using superfused mouse pancreatic fragments supported the in vivo result showing that substance P enhanced caerulein stimulated amylase output.     

2-arylalkanoates,a new group of synthetic pyrethroid esters not containing cyclopropanecarboxylates

Although structure modifications of natural pyrethrin constituents have disclosed a variety of potent synthetic analogues, all known examples are cyclopropanecarboxylate esters, a grouping that appeared to be essential for insecticidal activity. Some new substituted 2-phenylalkanoates, whose biological activities are of a similar nature and potency to those of conventional pyrethroids, are now reported. 5-Benzyl-3-furylmethyl and 3-phenoxybenzyl 3-methyl-2-phenylbutyrates and their analogues are potent insecticides. Activity is increased on the introduction of appropriate groups into the 3 and/or 4-positions of the aryl ring and the (S)-2-phenylalkanoates are far more active than their (R)-enantiomorphs. Structure/activity relationships are compared with those for conventional pyrethroids. Some of the new series compare favourably with typical insecticides in tests against Musca domestica, Spodoptera litura and Plutella xylostella.     

Gummy stem blight of balsam pear caused by <Emphasis Type="Italic">Didymella bryoniae</Emphasis> and its anamorph <Emphasis Type="Italic">Phoma cucurbitacearum</Emphasis>

Gummy stem blight of balsam pear found in the Kanto district and in the Hokkaido Prefecture was demonstrated to be caused by Didymella bryoniae (Auerswald) Rehm based on inoculation experiments, molecular analysis, and morphological identification of the pathogenic fungus. This fungus was also pathogenic to related plants belonging to Cucurbitaceae. The imperfect stage of the fungus was identified as Phoma cucurbitacearum (Fr.: Fr.) Sacc. based on morphological similarities.     

Effects of tall alleles SD1-in and SD1-ja to the dwarfing allele sd1-d originating from ‘Dee-geo-woo-gen’ on yield and related traits on the genetic background of indica IR36 in rice

sd1-d originating from ‘Dee-geo-woo-gen’ has been utilized to develop short-culmed indica varieties adaptable to higher fertilizer-application. Its tall alleles SD1-in and SD1-ja are harbored in indica and japonica subspecies, respectively. The sd1-d of indica IR36 was substituted with SD1-in or SD1-ja by recurrent backcrossing with IR36, and two tall isogenic lines (“5867-36” and “Koshi-36”) were developed. IR36, 5867-36 and Koshi-36 were grown in a paddy field in three years, and yield and related traits were measured, the effects of SD1-in and SD1-ja on yielding ability and related characteristics were examined on the genetic background of IR 36. SD1-in decreased panicle number per m² but increased spikelet number per panicle, ripened-grain percentage and 1000-grain weight, compared with sd1-d, resulting in the increase of yield. The increase of 1000-grain weight by SD1-in, caused by the increases of length, width and thickness of grain, was due to the increases of the length and width of lemma. SD1-ja did not significantly affect yield, mainly because the decrease of panicle number per m² was compensated by the enlarged 1000-grain weight owing to the increase of lemma length. Serious lodging was observed in long-culmed 5867-36, suggesting that sd1-d is indispensable for indica breeding programs.     

A rhabdomyosarcoma arising in the larynx of a dog

A neoplastic nodular lesion, 2 × 3 cm in diameter, was found in the larynx of a 6-year-old spayed female dog. The tumor was ill-circumscribed, consisting histologically of large round cells with abundant cytoplasm interspersed with small round cells with less cytoplasm and occasional multinucleated cells (myotubes). Immunohistochemically, tumor cells were positive for myoglobin, desmin and vimentin in varying degrees, but negative for S-100 protein, GFAP or cytokeratin. Cytoplasmic myofilaments/myofibrils with a dense Z-line-like structure were seen, the fine structures of which were complemented by PTAH stain. Based on these findings, the tumor was diagnosed as a rhabdomyosarcoma, a very rare tumor in the larynx of dogs.