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排序方式: 共有950条查询结果,搜索用时 15 毫秒
81.
Asako Kobayashi Junya Sonoda Kazuhiko Sugimoto Motohiko Kondo Norio Iwasawa Takeshi Hayashi Katsura Tomita Masahiro Yano Toyohiro Shimizu 《Breeding Science》2013,63(3):339-346
Decline in the apparent quality of rice (Oryza sativa L.) grain due to high temperatures during ripening recently became a major concern in many areas in Japan. The occurrence of white-back kernels (WBK) is one of the main problems of heat-induced quality decline. We identified QTLs associated with the occurrence of WBK using recombinant inbred lines (RILs) and verified their effects using near-isogenic lines (NILs). The QTL analysis used F7 and F8 RILs derived from ‘Hana-echizen’ (HE), which is tolerant to high temperature, × ‘Niigata-wase’ (NW), which is sensitive to high temperature. Four QTLs were identified on chromosomes 3, 4, 6, and 9 (qWB3, qWB4, qWB6 and qWB9). To verify the effects of qWB6 and qWB9, we developed two NILs in which qWB6 or both were introduced from HE into the NW background. The HE allele at qWB6 significantly decreased WBK under multiple environments. The combination of qWB6 and qWB9 in an F2 population derived from a cross between a NIL and NW showed that the NW allele at qWB9 significantly decreased WBK if the qWB6 allele was HE. These results will be of value in marker-assisted selection for the breeding of rice with tolerance to heat-induced quality decline. 相似文献
82.
83.
Tran Thi Thu Hoai Hiroaki Matsusaka Yoshiko Toyosawa Tran Danh Suu Hikaru Satoh Toshihiro Kumamaru 《Breeding Science》2014,64(2):142-148
Amylose content is one of the most important factors influencing the physical and chemical properties of starch in rice. Analysis of 352 Vietnamese rice cultivars revealed a wide range of variation in apparent amylose content and the expression level of granule-bound starch synthase. On the basis of single-nucleotide polymorphisms (SNP) at the splicing donor site of the first intron and in the coding region of the granule-bound starch synthase I gene, Waxy gene, alleles can be classified into seven groups that reflect differences in apparent amylose content. The very low and low apparent amylose content levels were tightly associated with a G to T in the first intron whereas intermediate and high amylose was associated with a T genotype at SNP in exon 10. The correlation between the combination of T genotype at SNP in the first intron, C in exon 6, or C in exon 10 was predominant among low amylose rice varieties. Our analysis confirmed the existence of Wxop allele in Vietnamese rice germplasm. The results of this study suggest that the low amylose properties of Vietnamese local rice germplasm are attributable to spontaneous mutations at exons, and not at the splicing donor site. 相似文献
84.
The effects of glucose concentrations, different sugars and combinations of 2,4-D and kinetin on cell division and colony formation were examined in cultures of protoplasts isolated enzymatically from suspension cultures of Iris hollandica N6 medium supplemented with 1 mg/l 2,4-D, 1 mg/l kinetin, 200 mg/l casein hydrolysate, 250 mg/l proline, 0.3– 0.5 M glucose and 20 g/l agarose was suitable for cell division and colony formation. When colonies formed were transferred to hormone-free MS medium, many shoots were induced. In addition, when induced shoots were transferred to MS medium with 1 mg/l NAA, root induction was observed. A plant regeneration system from protoplasts of I. hollandica was thus established. 相似文献
85.
Mariko Takano Muneysohi Yamaguchi Hiroaki Sano Masaya Nakamura Hajime Shibuya Yasumasa Miyazaki 《Journal of Wood Science》2013,59(2):141-148
The gene encoding manganese peroxidase of a white-rot fungus Phanerochaete crassa WD1694 was cloned and sequenced. Four genomic clones were sequenced in which 3 clones were existed as alleles. The analysis of intron–exon structures divided the 4 clones into three subfamilies that corresponded to mnp2 and mnp3 of Phanerochaete chrysosporium, and a new subfamily possessing only five introns. The purified P. crassa WD1694 MnP consisted of 4 isozymes with same molecular weight, same N-terminal sequence, and different pI. N-terminal sequence of deduced protein of P. crassa mnpB3 gene was identical to those of 4 MnP isozymes; however, the other 3 mnp genes had different N-terminal sequence. The molecular weight of encoded mature protein of mnpB3 gene and purified MnP had a gap that could be difference between MnP proteins encoded by single gene. The results suggested that 4 MnP isozymes of P. crassa WD1694 arose from single gene. 相似文献
86.
Tsutomu Suzuki Kyoko Suzuki Yukio Takahashi Mitsuhiro Okimoto Tetsuo Yamada Noriyasu Okazaki Yuichi Shimizu Masashi Fujiwara 《Journal of Wood Science》2007,53(1):54-60
Japanese larch wood loaded with nickel (1%–4%) alone or with nickel and calcium (0.25%–1.5%) was carbonized at 800°–900°C
for 0–120min with a heating rate of 5°–20°C min−1 in a helium flow of 5.8−46.4 ml STP cm−2 min−1 to examine the influence of these variables on the crystallization of carbon (the formation of T component) and the development
of mesoporosity. From the obtained results, reaction conditions suitable for effective production of carbon with the dual
functions of adequate electroconductivity and adsorption capacity in liquid phase were established, thereby explaining the
factors that govern the process. It was also confirmed that mesopore having a diameter of about 4 nm was selectively produced
at the cost of specific (BET) surface area in parallel with the formation of T component. This result provided good insight
into how the simultaneous dual function could be realized. 相似文献
87.
Kuniyoshi Shimizu Shoko Fukunaga Keisuke Yoshikawa Ryuichiro Kondo 《Journal of Wood Science》2007,53(2):153-160
The effects of 120 methanol extracts prepared from bark and heartwood of 69 types of Japanese wood on the melanin production
of B16 melanoma cells were examined. The melanin content of B16 melanoma cells was determined spectrophotometrically at 405nm.
The extracts were also examined for their effects on cell viability. We found that the methanol extracts of Fagus crenata (buna, wood, 100μg/ml), Sapium sebiferum (Nankinhaze, wood, bark, 10μg/ml), and Zelkova serrata (keyaki, wood, 10μg/ml) greatly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity.
However, these extracts did not inhibit tyrosinase activity at the concentration of 100μg/ml. These findings indicate that
the depigmenting mechanism of these extracts involves the suppression of some pigmenting signals in stimulating melanogenesis
rather than the inhibition of tyrosinase activity.
Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003 相似文献
88.
89.
Jie Liu Rumi Fujita Michiko Sato Kuniyoshi Shimizu Fumiko Konishi Kiyoshi Noda Shoichiro Kumamoto Chie Ueda Hisatoshi Tajiri Shuhei Kaneko Yoshitaro Suimi Ryuichiro Kondo 《Journal of Wood Science》2005,51(2):189-192
The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested. 相似文献
90.
BudiadiEmail author Yoichi?Kanazawa Hiroaki?T.?Ishii M.?Sambas?Sabarnurdin Priyono?Suryanto 《Agroforestry Systems》2005,64(2):143-155
Kayu putih oil, extracted from the kayu putih tree (Melaleuca leucadendron), is an important non-timber forest product (NTFP)
in Indonesia. We compared productivity of kayu putih tree plantations among three different sites in East, Central, and West
Java, Indonesia. Leaf-twig, and branch production per tree differed significantly among the three sites. Tree biomass production
was highest at the site in West Java practicing tumpangsari (a form of shifting cultivation) of kayu putih with rice (Oryza
sativa) on alluvial soils. Tree biomass production was lowest at the site in East Java, practicing tumpangsari of kayu putih
with maize (Zea mays) and cassava (Mani- hot esculenta). At this site, tree biomass production increased with increasing stand
age and low production was compensated by greater biomass yield of companion crops. Intermediate tree biomass production was
observed at the site in Central Java where intercropping is only practiced for the first two years after plantation establishment.
Production of tree biomass and kayu putih oil did not increase with increasing stand density, indicating that at a given site,
high tree stocking did not lead to high production. Stand-level productivity of the plantations increased with increasing
stand age and maximum productivity was attained at 15 to 35 years, after which productivity declined. This suggested unsustainable
stand productivity as plantations increase in age. 相似文献