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61.
The capabilities of four white‐rot fungi to improve the digestibility of sugarcane bagasse for ruminants were determined. Bagasse was cultured with Lentinula edodes, Pleurotus eryngii, Pleurotus salmoneostramineus, Ceriporiopsis subvermispora (ATCC 90467) or C. subvermispora (CZ‐3) at 26°C for 8, 12 or 16 weeks. The in vitro organic matter digestibility (IVOMD) and in vitro neutral detergent fiber digestibility (IVNDFD) in untreated bagasse were 45.6 and 40.3%, respectively. Meanwhile, the bagasse cultured with L. edodes and two strains of C. subvermispora, respectively, for 12 weeks, were elevated to 68.6 and 59.1%, 60.6 and 49.9% and 59.9 and 49.0%, respectively. In contrast, the IVOMD and the IVNDFD in bagasse cultured with P. eryngii and P. salmoneostramineus were the same or lower than those in untreated bagasse. In vitro gas production (IVGP) in bagasse cultured with L. edodes and two strains of C. subvermispora for 12 weeks was also higher than that of untreated bagasse. These changes in IVOMD, IVNDFD and IVGP demonstrate that L. edodes has a higher capability of improving the digestibility for ruminants than C. subvermispora, P. eryngii or P. salmoneostramineus.  相似文献   
62.
Phenolic extractives in the trunk of Toxicodendron vernicifluum (syn. Rhus verniciflua) were investigated. Seventeen compounds, gallic acid, protocatechuic acid, (?)-fisetinidol-4β-ol, (?)-fisetinidol-4α-ol, 2-benzyl-2,6,3′,4′-tetrahydroxycoumaran-3-one, (?)-fustin, 1,2,3,6-Tetra-O-galloyl-β-d-glucose, (?)-epifustin, (+)-taxifolin, 1,2,3,4,6-penta-O-galloyl-β-d-glucose, (?)-garbanzol, (?)-fustin-3-O-gallate, (?)-epifustin-3-O-gallate, fisetin, sulfuretin, quercetin and butein, were identified from the heartwood extractives. It was found that only (+)-taxifolin which had 5,7-dihydroxy A-ring possessed a 3R configuration although other flavonoids which had 7-hydroxy A-ring possessed a 3S configuration. Quantitative analysis revealed that the total phenolic contents were much higher in the heartwood (5–7 wt%) than in the sapwood and bark (1–2 wt%), and (?)-fustin was the most abundant extractive in the heartwood (1.4–2.4 wt%). For the radial distribution of phenolic extractives, it was generally found that their content was lowest in the sapwood, increased to the highest in the outer heartwood, and then decreased in the inner heartwood.  相似文献   
63.
Polyphenisms are adaptations in which a genome is associated with discrete alternative phenotypes in different environments. Little is known about the mechanism by which polyphenisms originate. We show that a mutation in the juvenile hormone-regulatory pathway in Manduca sexta enables heat stress to reveal a hidden reaction norm of larval coloration. Selection for increased color change in response to heat stress resulted in the evolution of a larval color polyphenism and a corresponding change in hormonal titers through genetic accommodation. Evidently, mechanisms that regulate developmental hormones can mask genetic variation and act as evolutionary capacitors, facilitating the origin of novel adaptive phenotypes.  相似文献   
64.
An annual Echinochloa with plagiotropic tillers (semi‐erect type) was found on a paddy levee in Miyagi prefecture in Japan. This semi‐erect type had tetraploid chromosome numbers (2n = 36) and would be expected to be E. oryzicola. However, its appearance was distinct from that of E. oryzicola. To collect seed samples and clarify its distribution and habitat, exploration and collection surveys were carried out in the northern part of Honshu, the main island of Japan in 2014, 2017, and 2018. Thirty‐two populations that were assumed to be the semi‐erect type were found and their mature seeds were collected. Based on the results of chromosome counts and growth form analyses, all of them were confirmed to be the semi‐erect type. The 32 populations were distributed in the prefectures of Aomori, Iwate, Akita, Miyagi, Yamagata, Fukushima, and Niigata, and located in paddy fields, abandoned paddy fields, paddy levees, roadsides, vacant land, and scree slopes. Our surveys indicated that the semi‐erect type grew in wet and dry disturbed habitats at an early stage of secondary succession including paddy fields in the northern part of the main island of Japan.  相似文献   
65.
Echinochloa crus‐galli (L.) Beauv. var. formosensis Ohwi (2n = 6x = 54, AABBCC genomes) and Echinochloa oryzicola (Vasinger) Vasinger (2n = 4x = 36, AABB) are major paddy weeds in East and Southeast Asia. E. oryzicola has been generally considered to be a paternal genome donor of E. crus‐galli s. l., which includes E. crus‐galli var. formosensis based on cpDNA sequences. Thus, molecular characterization using polymerase chain reaction‐restriction fragment length polymorphism analysis of cpDNA has been proposed as a reliable method for discriminating between the two species. In this study, we report that four accessions of E. crus‐galli var. formosensis from Okinawa, Nagasaki, Shizuoka and Tokyo had similar cpDNA sequences to E. oryzicola and had been misidentified as E. oryzicola using molecular methods. In addition, our results demonstrated that these accessions likely inherited their chloroplast genomes from E. oryzicola and not from an anonymous diploid species during polyploidization. Our findings provide new insights into the evolution of E. crus‐galli s. l. and suggest that identification using the cpDNA molecular method alone is not an appropriate approach to differentiate E. crus‐galli var. formosensis and E. oryzicola.  相似文献   
66.
This study revealed the spatial variation in abundance and body size of larval fishes in the Seto Inland Sea, Japan, in January 2014 and 2015. Fish larvae were collected by a 1.3-m-diameter ring net towed at the surface and at 10-m depth at 21 stations. The most dominant species was the sandlance Ammodytes japonicus, constituting 82% of total larval fish caught. The body size of A. japonicus was greater [ca. 9 mm total length (TL) in 2014] in eastern areas than in western areas (ca. 5 mm TL in 2014). This trend was also observed in rockfishes (Sebastiscus marmoratus and Sebastes inermis species complex), suggesting a common phenomenon in this region. Because the water temperature was lower in eastern areas, it is likely that the longitudinal differences in larval body size are attributable to earlier spawning in eastern areas caused by different temperature conditions.  相似文献   
67.
This study analyzes the effects of the Natural Forest Protection Program (NFPP) on the restoration of forest resources in  相似文献   
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