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Two Gram-stain-negative, terminal endospore-forming, rod-shaped and aerotolerant bacterial strains designated D1-1T and B3 were isolated from soil samples of an organic paddy in Japan. Strain D1-1T grew at 15–37 °C, pH 5.0–7.3, and with up to 0.5 % (w/v) NaCl. Phylogenetic analysis of the 16S rRNA gene revealed that strain D1-1T belonged to the genus Clostridium and was closely related to Clostridium zeae CSC2T (99.7 % sequence similarity), Clostridium fungisolvens TW1T (99.7 %) and Clostridium manihotivorum CT4T (99.3 %). Strains D1-1T and B3 were whole-genome sequenced and indistinguishable, with an average nucleotide identity value of 99.7 %. The average nucleotide identity (below 91.1 %) and digital DNA–DNA hybridization (below 43.6 %) values between the two novel isolates and their corresponding relatives showed that strains D1-1T and B3 could be readily distinguished from their closely related species. A novel Clostridium species, Clostridium folliculivorans sp. nov., with type strain D1-1T (=MAFF 212477T=DSM 113523T), is proposed based on genotypic and phenotypic data.

Rice bran application is practically used by Japanese organic rice farmers as a common measure in controlling Monochoria vaginalis, a known weed in organic rice production. To elucidate the inhibitory mechanisms of rice bran application on M. vaginalis germination, we focused on volatile fatty acids (VFAs) and aromatic carboxylic acids (ACAs) as organic acids produced through rice bran decomposition in the soil, which can possibly suppress M. vaginalis germination. Both solo solutions of 1 mM VFAs (propionic or isobutyric acid) and 0.2 mM ACAs (3-phenylpropionic or 4-phenylbutyric acid) exhibited M. vaginalis germination suppression, especially at pH 4.6, the lowest pH tested. In the 0.5–3 mM VFA solutions at pH 4.6, germination was strongly suppressed in the order of isobutyric > propionic > butyric > acetic acid. With the 0.05–0.2 mM ACA solutions at pH 4.6, the germination was strongly suppressed in the order of 3-phenylpropionic > 4-phenylbutyric > 2-phenylpropionic acid. Benzoic acid did not exhibit significant germination suppression. The solutions of 0.5 mM VFAs and 0.05 mM ACAs exhibited no suppression when applied separately; however, the certain mixture of a VFA and an ACA at the aforementioned concentration, for example, 0.5 mM isobutyric acid and 0.05 mM 3-phenylpropionic acid, exhibited significant germination suppression. These results showed the several combinations of VFAs and ACAs at even non-effective concentrations synergistically suppressed M. vaginalis germination. Abbreviations:2PPA: 2-phenylpropionic acid; 3PPA: 3-phenylpropionic acid; 4PBA: 4-phenylbutyric acid; ACA: aromatic carboxylic acid; EC: electrical conductivity; M. vaginalis: Monochoria vaginalis; VFA: volatile fatty acid

Organic paddy rice (Oryza sativa L.) cultivation can be negatively impacted because of the weeds growth like Monochoria vaginalis. Although the rice bran application is useful in combating weed, its performance is not consistent. In this study, laboratory experiments were conducted to elucidate the effects of rice bran on the suppression and promotion of germination of M. vaginalis. Suppression experiments involved incubating mixtures of flooded soil and rice bran. This was followed by a germination experiment in the collected soil solutions. A negative and significant correlation was observed between germination and the electric conductivity (EC) of the solution. None of the seeds germinated when the EC of the Gray Lowland soil was over 130 mS m−1. Conversely, the seeds in the Andosols’ solution germinated even when EC was over 130 mS m−1. Thus, the solutions of the Andosols had different mechanisms of suppression than the Gray Lowland soils. To understand the promotion of germination, air-dried soil was prepared after the flooded incubation of rice bran and soil mixture, simulating a long-term application of rice bran. Germination was analyzed in a filtrate of the mixture of air-dried soil and distilled water. The addition of rice bran significantly promoted germination. There was a negative and significant correlation between germination and dissolved oxygen (DO) suggesting that hardly decomposable components like antioxidants in rice bran decreased O2 and stimulated germination because the seeds of M. vaginalis require very little O2 for germination.

Flesh browning after cutting or bruising reduces the commercial value of apple fruit. Here, we investigated the genetic factors that regulate flesh browning (at 15 min and 24 h after grating) by a genome-wide association study (GWAS) of 24 sib-families (468 genotypes). Three quantitative trait loci (QTLs) were detected on chr5, chr16, and chr17. Their effects were estimated in a germplasm collection of 86 cultivars and selection lines: flesh browning differed with the genotypes of SNPs linked to these QTLs, respectively explaining 31.3%, 3.3%, and 23.7% of phenotypic variance at 15 min, and 36.7%, 11.0%, and 14.8% of variance at 24 h. Homozygous recessive alleles at these QTLs were associated with low browning. ‘Aori 27’, a rare cultivar that never browns even 5 days after grating, was homozygous recessive at all three QTLs. Browning was clearly lower in cultivars that were homozygous recessive at two QTLs, rather than one or none. We analyzed browning-related traits—polyphenol oxidase (PPO) activity, total polyphenol content, and juice browning—by GWAS using the germplasm collection. A QTL for PPO activity was detected on chr5, where PPO genes are located; and QTLs for total polyphenol content and juice browning were detected on chr16, where leucoanthocyanidin reductase gene is located. No QTLs for the browning-related traits were detected on chr17. These results indicate that the juice browning is mainly regulated by polyphenol content (chr16 QTL), whereas the flesh browning is also regulated by additional factors, including PPO activity (chr5 QTLs). These findings will facilitate development of non-browning apple cultivars.

Growth of the weed Monochoria vaginalis (Burm. f.) Kunth under the conditions of organic rice production is a serious problem. The reason for the growth of M. vaginalis being dominant, especially in organic rice production, is not fully understood. In this study, laboratory experiments were conducted to analyze soil and seed factors in relation to the promotion of germination. (1) After incubation of flooded soil with or without the addition of rice bran (0.3%, 0.6%, and 0.9% in an air-dried soil basis), soil solutions were recovered and seeds of M. vaginalis were incubated in the soil solutions. Germination in the soils solutions without and with 0.3% rice bran was greater than that in distilled water. However, germination was suppressed in the presence of 0.6% and 0.9% of rice bran. These findings indicate that the solution from the soils with rice bran has different effects that may either increase or decrease germination. (2) A mixture of air-dried soil and distilled water was filtered to obta...

Market demand for non-browning apple (Malus × domestica Borkh.) fruit is expected to increase. To facilitate development of non-browning cultivars, we investigated the origin, inheritance pattern, and causal genomic region of the non-browning trait through genetic and quantitative trait loci (QTL) analysis of two F1 populations (165A27 and KA27) derived from crosses between the non-browning cultivar ‘Aori 27’ and different browning lines. One third of the 165A27 population showed the non-browning trait. By QTL analysis using constructed genetic linkage maps, we detected major QTLs for multiple browning-related traits—flesh browning, juice browning, total polyphenols, and polyphenol oxidase activity—on almost the same region (i.e., upper part of LG 16) in the browning parents of both populations, but few on the ‘Aori 27’ maps. The QTL for flesh browning detected in the 165A27 population explained the majority of phenotypic variance, suggesting that the non-browning trait was mostly inherited through a single recessive locus or gene. Leucoanthocyanidin reductase 1 (LAR1), the key gene in polyphenol synthesis, which resides in the flesh browning QTL region, is the most probable candidate gene. To determine the origin of the non-browning alleles, we analyzed haplotypes around this major QTL in the two populations and their ancestors, and showed that ‘Aori 27’ and non-browning F1 individuals were functionally homozygous for non-browning alleles either derived from ‘Golden Delicious’, ‘Delicious’, or ‘Indo’. We consider the non-browning allele from ‘Indo’ to be a valuable resource, because unlike the alleles from the other cultivars, it is not linked with high acidity.

ストロビルリン系殺菌剤の一種であるピラクロストロビン剤がダイズの生育，収量構成要素および病害発生に及ぼす効果を異なる散布の時期および濃度条件下で解析した．2006年にピラクロストロビン剤をダイズの開花初期と開花終期に1333倍希釈（150 g成分量ha-1）で散布したところ，対照薬剤のイミノクタジンアルベシル酸塩水和剤の1000倍希釈（400 g成分量ha-1）散布区と比較して，開花終期散布区では成熟期の遅延と百粒重の増加が認められたが，開花初期散布区では明瞭な差は認められなかった．2007年に開花終期にピラクロストロビン剤を1500倍（133 g成分量ha-1），3000倍（67 g成分量ha-1），5000倍希釈（40 g成分量ha-1）で散布したところ，成熟期の遅延は認められなかったが，散布濃度の増加に伴い百粒重が増加する傾向にあり，同時に粒径の大きい子実の割合が高くなった．また，散布時期や散布濃度に関わらず，ピラクロストロビン剤散布は対照薬剤のイミノクタジンアルベシル酸塩剤散布と比較して紫斑粒の発生を有意に抑制した．さび病，葉焼病および褐紋病の発生量は処理区間で差が認められなかった．これらのことから，ピラクロストロビン剤の開花終期散布は紫斑粒発生の抑制のみならず，子実の百粒重と粒径増大にも効果があると考えられる．

土壌過湿条件下においてダイズの出芽率が低下する要因と調湿種子による出芽の安定化について室内と圃場において解析を行った．その結果，土壌過湿条件下における出芽率の低下では，吸水障害のほかに，土壌微生物と土壌表面硬度が大きく関与していた．また，調湿種子の出芽率は，播種時の土壌水分や出芽時の土壌表面硬度が高い場合には乾燥種子と比べて大幅に向上した．しかし，播種後も土壌の過湿状態が続いた場合は調湿種子を利用しても出芽率が低下し，この場合は種子粉衣殺菌剤の併用により出芽率が改善された．圃場における出芽率の低下の要因は気象条件や土壌条件によって異なったが，多くの場合で調湿種子と種子粉衣殺菌剤の併用により出芽率が高まった．それゆえ，この両者の併用は土壌過湿条件下におけるダイズの出芽の安定化に有効である．

Soybean cultivar Enrei and its derivative lines, non-nodulating En1282 and supernodulating Sakukei 4, were grown in an experiment field naturally infested with the red crown rot fungus, Calonectria ilicicola, to determine whether nodulation elicits the disease. Infection frequency by the fungus invariably increased with time and reached about 100% 6 weeks after sowing. Disease severity was invariably slight until 8 weeks after sowing. At harvest, however, disease severity was lowest in En1282 and highest in Sakukei 4. Enrei was intermediately susceptible. Sakukei 4 produced many more nodules than Enrei, while En1282 completely failed to nodulate. For three other pairs of nodulating and non-nodulating isogenic lines, all non-nodulating lines had lower severity than their nodulating counterparts at harvest. Pot experiments with Enrei and its derivatives revealed that inoculation with Bradyrhizobium sp. did not affect disease severity during the vegetative stage of plant growth, i.e., 6 weeks after sowing. These results suggested that the production of nodules in the vegetative stage is not, at least directly, related to susceptibility to the disease, but physiologic changes after anthesis vary depending on the nodulation traits in the respective soybean lines, resulting in different levels of susceptibility to red crown rot.

The nitrogen uptake and yielding ability of non-nodulating soybean genotype (En1282) were investigated under field conditions. Dried cattle feces were applied at levels ranged from 192 to 960 kg N/ha for seven years. No-fertilizer and inorganic fertilizer treatments were used as controls in this experiment. The grain yield of non-nodulating En1282 increased as the application of cattle feces was increased up to 384 kg N/ha. The maximum grain yield of non-nodulating soybean was 3.6t/ha, and the maximum nitrogen uptake was 250kg N/ha. Nitrogen uptake of upland rice, maize (sweet corn), maize (dent corn), radish, wheat, rye, guinea grass and non-nodulating soybean, cultured in the same field over a seven-year period, were compared. The nitrogen uptake ranged from 100 to 300kg N/ha among the crops; it was lowest in upland rice, and highest in guinea grass, followed by soybean. The nitrate content of guinea grass was very high and exceeded the toxic limits for animal feed. In soybean, the shoot nitrate level was high and close to toxic limits during flowering, but nitrate levels of grain, pod and stem were low at maturity. This fitted for animal feed. Our results indicate that non-nodulating soybean can be effectively used to retrieve inorganic nitrogen that is derived from organic nitrogen (such as animal feces), and can play some role in reducing nutrient load on the farming systems.

Groundnut showed a superior ability to take up P from a soil with low P fertility compared with sorghum and soybean. This ability was not related to its better root development or production of root exudates capable of solubilizing iron-and aluminum-bound P. In efforts to determine the role of roots per se, we found that root cell walls from groundnut showed a higher P-solubilizing activity than those from soybean or sorghum. This finding corresponds well with observations in field and pot experiments using a soil with low P availability. The reaction site of P-solubilizing activity is stable against heating and enzyme digestion by cellulase and pectinase. This is probably the first evidence to demonstrate that cell walls of plant roots are involved in P-solubilizing activity. ei]Section editor: H Marschner (deceased 21 September 1996)

We propose an efficient hardware accelerator for the calculation of accumulated values of two-dimensional continuous dynamic programming (2DCDP). The 2DCDP is a powerful optimal pixel-matching algorithm between input and reference images which can be applied to image processing, such as image recognition, image search, feature tracking, 3D reconstruction, and so on. However, it requires large computation time due to its time and space complexities of O(N^4 ). We analyze the computation flow of the 2DCDP algorithm and propose a high-performance architecture for a hardware accelerator. Parallelized accumulated minimum local distance calculators and a toggle memory structure are newly introduced to reduce the computation cost and memory. The proposed architecture is implemented into an FPGA, Stratix IV, EP4SE820. Its maximum operation frequency is 125.71 MHz. The preliminary evaluation reveals that the parallel processing by 32 PEs for the accumulated value calculation for 32x32 input and reference images can be sped up to 77 times at the maximum operation frequency of 100 MHz compared to the processing with a multi-core processor.

Effects of pamamycins on [Ca2 +]i in Streptomyces alboniger were examined by microscopic fluorometry. Pamamycin-607, which has aerial mycelium-inducing activity, induced a transient increase in [Ca2+]i dose-dependently, but the inactive pamamycin-649 had no effect on [Ca2+]i.

Nine new pamamycin homologues were isolated from the culture broth of Streptomyces alboniger IFO 12738 using a combination of ODS and NH2 HPLCs, and their structures determined by GC-MS. The structural differences in these homologues are in the numbers and positions of methyl and ethyl groups. The aerial mycelium-inducing and growth-inhibitory activities in S. alboniger of these homologues and their antibiotic activity against Bacillus subtilis were examined. The effects of the alkyl substituents on these activities are discussed.