Effect of cross-sectional dimensions on bow and surface checking of sugi (Cryptomeria japonica) boxed-heart square timber dried by conventional kiln drying

The effect of cross-sectional dimensions on bow and surface checking were investigated, using the boxed-heart square timber of two sugi cultivars with dimensions 80, 120, and 140 mm and length 1.9 m taken at two different heights above the ground. The smaller cross-sectional timber tended to have larger bow, less surface checking, and larger dimensional shrinkage. However, the drying defects were different between the cultivars and sampling heights, depending on the shrinkage properties of the juvenile wood and the heartwood proportion in the core part of the stem. The bow was larger in the smaller cross-sectional timber in which the longitudinal shrinkage was large in the juvenile wood. Surface checking was more prominent in larger cross-sectional timber containing sapwood in its outer part, which suggested the surface checking was induced by drying stress, owing to large moisture gradients between the heartwood and sapwood. The cross-dimensional shrinkage of the timber was larger in timber with larger tangential shrinkage.     

A RAPD-derived STS marker is linked to a bacterial wilt (Burkholderia caryophylli) resistance gene in carnation

Bacterial wilt caused by Burkholderia caryophylli is one of the most important and damaging diseases of carnations (Dianthus caryophyllus) in Japan. We aimed to identify random amplified polymorphic DNA (RAPD) markers associated with the genes controlling bacterial wilt resistance in a resistance-segregating population of 134 progeny plants derived from a cross between Carnation Nou No. 1 (a carnation breeding line resistant to bacterial wilt) and Pretty Favvare (a susceptible cultivar). We screened a total of 505 primers to obtain RAPD markers useful for selecting resistant carnation lines: 8 RAPD markers identified by bulked segregant analysis were linked to a major resistance gene; of these, WG44-1050 had the greatest effect on resistance to bacterial wilt. A locus with large effect on bacterial resistance was mapped around WG44-1050 through QTL analysis. The RAPD marker WG44-1050 was successfully converted to a sequence-tagged site (STS) marker suitable for marker-assisted selection (MAS). Five combinations of primers were designed for specific amplification of WG44-1050. In addition, the STS marker we developed was useful and reliable as a selection marker for breeding for resistance to bacterial wilt, using a highly resistant wild species, D. capitatus ssp. andrzejowskianus and a resistant line, Carnation Nou No. 1, as breeding materials.     

Resistance levels of sulfonylurea‐resistant Schoenoplectus juncoides (Roxb.) Palla with various Pro197 mutations in acetolactate synthase to imazosulfuron,bensulfuron‐methyl,metsulfuron‐methyl and imazaquin‐ammonium

An investigation, using herbicidal pot tests in a greenhouse condition, was conducted to determine the whole‐plant dose–response relationships to several acetolactate synthase (ALS)‐inhibiting herbicides of sulfonylurea (SU)‐resistant Schoenoplectus juncoides with various Pro₁₉₇ mutations in ALS that was collected from Japanese rice paddy fields. All the tested SU‐resistant accessions with a Pro₁₉₇ mutation were highly resistant to two commonly used SU herbicides (imazosulfuron and bensulfuron‐methyl), but were much less resistant to another SU herbicide, metsulfuron‐methyl, and were substantially not resistant to imazaquin‐ammonium. These cross‐resistance patterns have been known previously in fragments of S. juncoides and other weed species and were comprehensively confirmed in this study with a whole set of Pro₁₉₇ mutations. The analyses of resistance levels, based on ED₉₀ values, newly showed that different accessions with a common amino acid substitution in ALS1 showed similar responses to these herbicides (confirmed with four amino acid substitutions), that the rankings of resistance levels that were conferred by various Pro₁₉₇ mutations in ALS1 differed among the SU herbicides and that the resistance levels of the ALS2‐mutated accessions were higher than, lower than or similar to those of the corresponding ALS1‐mutated accessions, depending on the compared pair, but the deviation patterns were generally similar among the SU herbicides in each compared pair. The final finding might suggest that the abundance of ALS2 is not as stable as that of ALS1. In addition, as a result of these new findings, together with expected further research, a suggested possibility is that substituting amino acids at Pro₁₉₇ generally could be estimated by plotting each accession's ED₉₀ values of imazosulfuron and bensulfuron‐methyl in a two‐dimensional graph.     

Altitudinal life-cycle and body-size variation in ground beetles of the genus Carabus (subgenus Ohomopterus) in relation to the temperature conditions and prey earthworms

The body size of univoltine insect species generally decreases with increasing altitude or latitude. This pattern may have arisen from adaptations to multiple factors that potentially affect body-size variation, such as temperature, food, and interspecific interactions. We examined altitudinal variations in life history and body size, and their relationships to temperature and food resources in two ground beetle species of the genus Carabus (subgenus Ohomopterus; C. tosanus and C. japonicus) in a mountainous area (altitude 860–1730 m) of Shikoku Island, Japan. Larvae of these species are specialist predators of earthworms. The body size of C. tosanus decreased with an increase in altitude. Carabus japonicus, which is much smaller than C. tosanus, exhibited similar sizes across altitudes, although it was not abundant at high altitudes. Available cumulative temperatures for larval development were limited at higher altitudes, and C. tosanus started reproducing 1 month earlier at higher than at lower altitudes. Earthworms (larval food) were less abundant at higher than at lower altitudes. This may imply that food resources also restrict the optimal body size of C. tosanus at higher altitudes.     

Biallelic inactivation of BRCA2 in Fanconi anemia

Fanconi anemia (FA) is a rare autosomal recessive cancer susceptibility disorder characterized by cellular hypersensitivity to mitomycin C (MMC). Six FA genes have been cloned, but the gene or genes corresponding to FA subtypes B and D1 remain unidentified. Here we show that cell lines derived from FA-B and FA-D1 patients have biallelic mutations in BRCA2 and express truncated BRCA2 proteins. Functional complementation of FA-D1 fibroblasts with wild-type BRCA2 complementary DNA restores MMC resistance. Our results link the six cloned FA genes with BRCA1 and BRCA2 in a common pathway. Germ-line mutation of genes in this pathway may result in cancer risks similar to those observed in families with BRCA1 or BRCA2 mutations.     

Relationships between immunoglobulin M and immunoglobulin G or A in colostrum of Japanese black multiparous cows

This study was conducted to clarify the relationships among immunoglobulin (Ig)M, IgG, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of 24 Japanese Black multiparous cows in order to evaluate the role of IgM on colostral IgG and IgA production. Compared with colostral IgG, colostral IgM and IgA were very low but varied widely. There was positive correlation between colostral IgM and IgG, but colostral IgM was not related with colostral IgA. There was no relationship between colostral IgM and age of cows, although colostral IgG was increased with aging. There were positive correlations among colostral β‐carotene, vitamin A and α‐tocopherol and these vitamins were positively correlated with colostral IgM and IgG. These results indicate that fat‐soluble vitamins may affect colostral IgG and IgM in cows and colostral IgG increases with the increase of colostral IgM.     

Mathematical Model of Lateral Oxygen Diffusion and Respiration of Roots for Estimating the Diffusion Coefficient and Affinity to Oxygen

We propose herein a mathematical model, for calculating the oxygen diffusion coefficient (D) and K _m value of a cell (M) based on oxygen concentration-respiration rate curve obtained under the condition that oxygen was supplied by lateral diffusion in roots. The model was deductively developed on the assumption that the roots were uniform and cylindrical and that the oxygen concentration and respiration rate were interdependent.

We estimated D and M from the oxygen concentration-respiration curves of rice (cv. Fujisaka 5) and wheat (cv. Chinese Spring) using this model. These values showed a certain range as follows. In rice, 0.003 cm² h^-1 ≤ D < 0.037 cm² h^-1, and 0.55 μmol mL^-1 ≤ M < 0.75 μmol mL^-1, in wheat, 0.016 cm² h^-1 ≤ D < 0.093 cm² h^-1, and 2.1 μmol mL^-1 ≤ M < 2.2 μmol mL^-1. By comparing the values, rice appeared to be more adapted to hypoxia than wheat, because rice had lower D and M values implying the existence of a safeguard mechanism and high affinity to oxygen. Higher oxygen uptake rate under hypoxia in rice was derived from the lower M value, which exceeded the low D.