Collaborative non-self recognition system in S-RNase-based self-incompatibility

Self-incompatibility in flowering plants prevents inbreeding and promotes outcrossing to generate genetic diversity. In Solanaceae, a multiallelic gene, S-locus F-box (SLF), was previously shown to encode the pollen determinant in self-incompatibility. It was postulated that an SLF allelic product specifically detoxifies its non-self S-ribonucleases (S-RNases), allelic products of the pistil determinant, inside pollen tubes via the ubiquitin-26S-proteasome system, thereby allowing compatible pollinations. However, it remained puzzling how SLF, with much lower allelic sequence diversity than S-RNase, might have the capacity to recognize a large repertoire of non-self S-RNases. We used in vivo functional assays and protein interaction assays to show that in Petunia, at least three types of divergent SLF proteins function as the pollen determinant, each recognizing a subset of non-self S-RNases. Our findings reveal a collaborative non-self recognition system in plants.     

Effects of whey protein hydrolysate on growth promotion and immunomodulation in mouse pups in artificial rearing system

This study aimed to investigate the effects of whey protein hydrolysate (WPH) on the growth and immunity of mouse pups in artificial rearing (AR) system. Mouse pups were reared in the AR system with artificial milk including 5% WPH (AR with WPH) or not (AR without WPH), and the remaining pups were reared by their mother (dam) for 14 days after birth. The body weight change and body weight gain rates in the AR with WPH group were significantly higher than those observed in the AR without WPH group and similar to those in the dam group. Moreover the feed and protein efficiencies in the AR with WPH group were significantly higher than those of the AR without WPH group. In addition, the supplement of WPH in the AR system was shown to significantly elevate the number of CD3⁺CD8⁺, B220⁺CD19⁺, IA/IE⁺CD11c⁺, and CD11b⁺ in the thymocyte and/or splenocyte, and the thymus weight. Furthermore, MALDI‐TOF/MS analysis identified the amino acid sequences corresponding to some peptides, and indicated that VRTPEVDDE had the highest relative intensity among the peptides from tested WPH. Therefore, WPH would be required to not only promote growth, but also exert immunomodulatory activities in mouse pups in AR system.     

Genetic and genomic analyses for predicted methane‐related traits in Japanese Black steers

The objectives of this study were to estimate genetic parameters and to perform a genome‐wide association study (GWAS) for predicted methane‐related traits in Japanese Black steers. The methane production and yield traits were predicted using on‐farm measurable traits, such as dry matter intake and average daily gain. A total of 4,578 Japanese Black steers, which were progenies of 362 sires genotyped with imputed 551,995 single nucleotide polymorphisms (SNPs), had phenotypes of predicted methane‐related traits during the total fattening period (52 weeks). For the estimation of genetic parameters, the estimated heritabilities were moderate (ranged from 0.57 to 0.60). In addition, the estimated genetic correlations of methane production traits with most of carcass traits and feed‐efficiency traits were unfavorable, but those of methane yield traits were favorable or low. For the GWAS, no genome‐wide significant SNP was detected, but a total of four quantitative trait locus (QTL) regions that explained more than 5.0% of genetic variance were localized on the genome, and some candidate genes associated with growth and feed‐efficiency traits were located on the regions. Our results suggest that the predicted methane‐related traits are heritable and some QTL regions for the traits are localized on the genome in Japanese Black steers.     

Genotypic variation in Fe concentration of barley grain

Abstract

Iron deficiency in humans is the most prevalent micronutrient deficiency worldwide. To screen for high Fe cultivar, genotypic variation in Fe concentration of barley grain was investigated in two collections of barley: 274 standard varieties selected at the Barley Germplasm Center of the Research Institute for Bioresources, Okayama University (SV) and 135 varieties from the Barley Core Collection of Americas (BCCAM). The Fe concentration of barley grain showed large variation, ranging from 24.6 to 63.3 mg kg^?1 in SV, from 21.0 to 83.0 mg kg^?1 in BCCAM barleys. The Fe concentration was not affected by the key characters of barley varieties, kernel row types, and hulled or hull-less. The Fe concentration was also not related to the place of origin of the barley variety. About 90% of total Fe was localized in the grain without hull. These results provide fundamental data for breeding Fe-rich cultivars and for studying the mechanisms involved in genotypic variation in Fe concentration.     

Combining pre-transplanting phosphorus application and green manure incorporation: a trial for reducing fertilizer input

Pre-transplanting phosphorus application is a fertilization method that can reduce phosphorus (P) fertilization of the field and increase P use efficiency. We investigated whether P use efficiency can be increased further by combining pre-transplanting phosphorus application and the green manure practice, using cabbage as a test plant in a field experiment performed from 2006 to 2008. The pre-transplanting phosphorus application successfully reduced P fertilization of the field to half without any yield losses in 2006 and 2008. However, growth and yield could not be maintained with the pre-transplanting phosphorus application when P fertilization was halved in 2007. Differences among seasons and discrepancies in the results compared to previous studies may have arisen from the differences in the field management and the nursery soil used. No benefits of green manure in terms of the subsequent cabbage yield were detected. Consequently, there was no positive effect of the combination of pre-transplanting phosphorus application and incorporation of green manure. Studies with mycorrhizal plants as test plants may be necessary to verify the mechanism of enhanced P supply by the incorporation of green manure, and to examine any potential benefit of combining green manure and pre-transplanting phosphorus application practices.     

An examination of the total analysis of major elements in soil samples

Recently conventional chemical analyses were mostly replaced by instrumental analysis. Although results from both methods were examined in details after the samples had been solubilized or extracted by appropriate techniques, the solubilization method was considerably altered so as to be convenient for the following analysis. In atomic absorption spectrophotometry (AAS), for example, fusion technique was mostly inadequate because of the higher salts concentration in the obtained solution. The use of H₂SO₄ must also be avoided in acid digestion for SO₄ ^2- precipitates with Sr²⁺ or La³⁺ which must be added to eliminate interferences in the succeeding procedure. Therefore, it is essential to consider the whole scheme including sample treatments to evaluate the suitability of instrumental analysis. In this experiment, the suitability of the methods which have been employed in our laboratory was examined by analyzing 9 rock standards.     

QTLs in barley controlling seedling elongation of deep-sown seeds

In drought areas, in which topsoil moisture is low, barley seeds are generally sown in the subsoil (deep-seeding). In order for the shoots of germinating seeds to emerge from the deep soil cover, the coleoptile and the first internode of the seedlings must elongate as an adaptive response to deep-seeding. Here, we have mapped quantitative trait loci (QTLs) for these adaptive characteristics. Elongation of the coleoptile and first internode was investigated using seeds sown under two soil cover conditions: at a depth of 9 cm beneath a soil mixture; and, at a depth of 12 cm beneath vermiculite. We identified multiple alleles for increased coleoptile and first internode elongation using a doubled haploid population of 150 lines generated from a cross between the barley cultivars Harrington and TR306. Composite interval mapping analyses of the data revealed two moderate and eleven small effect QTLs, with at least one QTL on each chromosome. The QTLs on chromosomes 5H and 7H had moderate effects on coleoptile elongation (18.5–27.6% of PVE: phenotypic variance explained; 2.6–3.2 mm of Add: additive effect) and first internode elongation (PVE: 16.6–19.6%; Add: 3.1–3.2 mm). The small effect QTLs showed PVEs of less than 15% and an Add range of 1.2–3.2 mm for both characters. A marker assisted selection approach, using markers linked to the QTLs for seedling elongation at deep-seeding, may eventually enable development of drought tolerant barley hybrids.     

Mesoscale eddies modulate the dynamics of human fishing activities in the global midlatitude ocean

Frequent fishing activities are causing overfishing, destroying the habitat of marine life, and threatening global marine biodiversity. Understanding the dynamics of fishing activities and their drivers is crucial for designing and implementing effective ocean management. The fishing activities in the open sea are reported to be characterized by high spatial variability in local waters; however, it is still unclear whether their high spatial variability is random or regulated by oceanographic variations. Mesoscale eddies are ubiquitous swirling currents that dominate locally biogeochemical processes. Previous case studies presented an ongoing debate regarding how eddies exert impacts on high trophic organisms, which imposes limitations on understanding the dynamics of fishing activities based on the bottom-top control hypothesis from eddies to fish and fishing activities. By combining global fishing activities from deep learning and oceanic eddy atlases from satellite monitoring, we showed that the spatial variations in fishing activities were closely related to mesoscale eddies in the global midlatitude ocean, confirming that fishing activities primarily targeting tuna, were aggregated in (repelled from) anticyclonic (cyclonic) eddy cores. This eddy-fishing activity relationship was opposite to satellite-observed primary production but corresponded well with the temperature and oxygen content in deeper water. By integrating existing evidence, we attribute eddy-related fishing activities to a reasonable hypothesis that warm and oxygen-rich deeper water in anticyclonic eddies relieves the thermal and anoxic constraints for diving predation by tuna while the constraints are aggravated in cold and oxygen-poor cyclonic eddies.     

Detection of Thiophanate-methyl-resistant Strains in Diplocarpon mail, Causal Fungus of Apple Blotch

Isolates of Diplocarpon mali, causal fungus of apple blotch, collected from four prefectures in Japan in 1997–1998 were tested for sensitivity to thiophanate-methyl. Results from mycelial growth tests showed that MIC values of the fungicide were 0.19 μg/ml against all isolates from Akita, Nagano and Saga prefectures but 100 or 200 μg/ml against all isolates from the Tokusa area in Yamaguchi prefecture. Detached apple leaves sprayed with the fungicide developed severe symptoms when inoculated with the isolate from Tokusa, but developed no symptoms with the isolate from Nagano. These results are the first confirmation of thiophanate-methyl-resistant strains in D. mali. Received 1 September 1999/ Accepted in revised form 15 October 1999