Identification of avirulence genes in the rice blast fungus corresponding to three resistance genes in Japanese differentials

The pathogenicity of progeny from crosses among three Chinese isolates of Magnaporthe grisea collected from rice was tested on three Japanese differentials (Ishikarishiroke, Aichiasahi, K 59) having the blast resistance genes Pii, Pia, and Pit, respectively. Monogenic control was demonstrated for avirulence to the differentials. To identify resistance genes corresponding to the avirulence genes, the resistance and susceptibility in F₃ lines of the cultivars in response to the parents of the crosses were analyzed genetically. The three avirulence genes identified, designated Avr-Pii, Avr-Pia, and Avr-Pit, appear to correspond to resistance genes Pii, Pia, and Pit, respectively. The monogenic control of avirulence in the fungus and monogenic dominant resistance in rice cultivars supports a gene-for-gene relation in the Pii-, Pia-, or Pit-dependent resistance to the rice blast fungus in rice cultivars.     

Feeding deterrent and growth inhibitory properties of limonoids from Khaya senegalensis against the cotton leafworm, Spodoptera littoralis

Three rearranged phragmalin-type limonoids, khayanolide A, khayanolide B and 1-O-acetylkhayanolide B, and a mexicanolide-type limonoid, khayalactol, have been isolated from the stem bark of Khaya senegalensis (Desr) A Juss (Meliaceae). The antifeedant and growth-inhibitory activities of the isolated compounds were evaluated on Spodoptera littoralis (Boisduval). When added to an artificial diet, khayanolide A, khayanolide B and 1-O-acetylkhayanolide B showed antifeedant activity in a concentration-dependent manner. Khayalactol exhibited strong antifeedant activity without significant differences at all of the tested concentrations (7.5-100 mg kg(-1)). Khayanolide B was the most potent antifeedant with an ECso of 2.19 mg kg(-1). The results also revealed that the isolated compounds caused marked larval growth inhibition on S littoralis after 7 days of feeding on treated diet; this effect was concentration-dependent. Khayanolide B was the most active growth inhibitor among the isolated compounds, with an EC50 of 6.96 mg kg(-1).     

Shotgun proteomic analysis of porcine colostrum and mature milk

The epitheliochorial nature of the porcine placenta prevents the transfer of maternal immunity. Therefore, ingestion of the colostrum immediately after birth is crucial for neonatal piglets to acquire passive immunity from the sow. We performed a shotgun proteomic analysis of porcine milk to reveal in detail the protein composition of porcine milk. On the basis of the Swiss‐Prot database, 113 and 118 proteins were identified in the porcine colostrum and mature milk, respectively, and 50 of these proteins were common to both samples. Some immune‐related proteins, including interleukin‐18 (IL‐18), were unique to the colostrum. The IL‐18 concentration in the colostrum and mature milk of four sows was measured to validate the proteomic analysis, and IL‐18 was only detected in the colostrum (191.0 ± 53.9 pg/mL) and not in mature milk. In addition, some proteins involved in primary defense, such as azurocidin, which has never been detected in any other mammal's milk, were also identified in the colostrum.     

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.     

Influence of the nitrogen form on in vitro organogenesis in Equisetum arvense

The physiological and biochemical mechanisms of organogenesis in Equisetum arvense have not been clarified yet. However, high concentrations of nitrogen have been shown to exert an inhibitory effect on in vitro tuber formation in E. arvense. The aim of this study was to clarify the influence of the form of nitrogen in a medium on in vitro organogenesis in E. arvense. Single‐node segments of E. arvense rhizomes were cultured in the test medium. The NH₄‐N and NO₃‐N concentrations of the test medium, respectively, were adjusted by adding NH₄H₂PO₄ and KNO₃ to the basal medium. The basal medium was a nitrogen‐free, modified form of White's medium. Vegetative shoots were newly formed in the test tubes for concentrations of NO₃‐N and NH₄‐N that exceeded 56 mg L^?1. However, no rhizome was formed at NH₄‐N concentrations exceeding 28 mg L^?1. The number of newly formed tubers decreased at an NH₄‐N concentration of 28 mg L^?1 and no tuber was formed at NH₄‐N concentrations exceeding 56 mg L^?1. In summary, although the presence of NO₃‐N in the medium did not inhibit in vitro rhizome or tuber formation in E. arvense, the presence of NH₄‐N in the medium exerted a strong inhibitory effect on the in vitro formation of both of these organs.     

Continuous plasma outflows from the edge of a solar active region as a possible source of solar wind

The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, located adjacent to a coronal hole, a pattern of continuous outflow of soft-x-ray-emitting plasmas was identified emanating along apparently open magnetic field lines and into the upper corona. Estimates of temperature and density for the outflowing plasmas suggest a mass loss rate that amounts to approximately 1/4 of the total mass loss rate of the solar wind. These outflows may be indicative of one of the solar wind sources at the Sun.     

Selection of spawning habitat by several gobiid fishes in the subtidal zone of a small temperate estuary

We examined the spawning sites of several gobiid fishes in the subtidal zone of a small temperate estuary and determined the relationship of the nest abundance of each species with several environmental conditions, including water temperature, salinity, median particle size, proportion of silt and clay, current width, maximum water depth, distance from each site to the river mouth, and density of objects (boulders, cobbles, empty oyster shells, and empty clam shells) in the water. During this study, we found 115 nests belonging to the following six species: Favonigobius gymnauchen, Tridentiger obscurus, Leucopsarion petersii, Acanthogobius lactipes, Rhinogobius giurinus, and Tridentiger trigonocephalus. Stepwise multiple regression analysis, which was used to determine the best model for the nest abundance of all species, revealed that the nest abundance of each species clearly increased with an increase in the density of spawning substrates, such as cobbles and bivalve shells. These results show that the density of spawning substrates is a crucial factor affecting the selection of spawning habitats by each species.     

Influence of Amylose Content on Cookie and Sponge Cake Quality and Solvent Retention Capacities in Wheat Flour

Reduced amylose wheat (Triticum æstivum L.) produces better quality noodles and bread less prone to going stale, while little is known about the relationships between amylose content and the quality of soft wheat baking products such as sugar snap cookies (SSC) and Japanese sponge cakes (JSC). Near‐isogenic lines developed from wheat cultivar Norin 61, differing in their level of granule‐bound starch synthase (Wx protein) activity, were used to produce wheat grains and ultimately flours of different amylose contents. These were tested with regard to their effect on soft wheat baking quality and solvent retention capacities (SRC). Amylose content was strongly correlated to cookie diameter (r = 0.969, P < 0.001) and cake volume (r = 0.976, P < 0.001), indicating that the soft wheat baking quality associated with SSC diameter and JSC volume were improved by an incremental increases in amylose content. Among the four kinds of SRC tests (water, sodium carbonate, sucrose and lactic acid), the water SRC test showed the highest correlation with amylose content, SSC diameter, and JSC volume. When the regression analysis was conducted between the nonwaxy and partial waxy isogenic lines that are available in commercial markets, only water SRC was significantly correlated to amylose content (r = –0.982, P < 0.001) among of four SRC tests. This suggests that, unlike udon noodle quality, high‐amylose content is indispensable in improving soft wheat baking quality, a process requiring less water retention capacity.     

Effect of Growing Environment of Soft Wheats on Amylose Content and Its Relationship with Cookie and Sponge Cake Quality and Solvent Retention Capacity

The effect of growing environments of soft wheat on amylose content and its relationship with baking quality and solvent retention capacities (SRC) was investigated. Near‐isogenic soft wheat lines of Norin 61 differing in granule‐bound starch synthase (Wx protein) activity and grown in three different regions of Japan: Hokkaido (spring‐sown) for 2006 and 2007, Kanto (autumn‐sown), and Kyushu (autumn‐sown) for 2007 were evaluated. Spring‐sown samples produced grains of greater protein content (10.9–12.4%) than autumn‐sown samples (7.3–9.1%). In contrast, spring‐sown samples of 2007 with higher maturing temperature had lower amylose content (25.5% for Norin 61) compare to the autumn‐sown and spring‐sown samples of 2006 (27.6–28.4% for Norin 61). Amylose content was strongly correlated to sugar snap cookie (SSCD) diameter (r = 0.957–0.961; n = 10, all samples; P ≤ 0.001, r = 0.701–0.976; n = 7 partial waxy and nonwaxy samples; and Japanese sponge cake (JSCV) volume r = 0.971–0.993; n = 10; P≤ 0.001, r = 0.764–0.922; n = 7 partial waxy and nonwaxy samples), regardless of seeding season and growing conditions. The strength of the JSVC‐amylose relationship (slope) was similar among the three regions, whereas the strength of the SSCD‐amylose relationship was slightly weaker for spring‐sown samples and slightly stronger for partial waxy and nonwaxy autumn‐sown samples. Among of the four solvents (water, solutions of sodium carbonate, sucrose, or lactic acid), water‐SRC showed the greatest correlation to amylose content (r = –0.969 to –0.996; n = 10; P ≤ 0.001, r = –0.629 to –0.983; n = 7 partial waxy and nonwaxy samples), indicated that amylose content can be accurately estimated from the water‐SRC within the samples from the same grown environment.