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991.
Tomiki Kobayashi Yoshihiro Nakagawa Motonori Tamaki Takatoshi Hiraki Masahide Aikawa 《Water, air, and soil pollution》2001,130(1-4):601-606
Cloud water deposition to canopies of Cryptomeria japonica at Mt.Rokko, Kobe, Japan, was estimated from throughfall measurements and fog water collections carried out during a full year. Annual cloud frequency was 11.5–15.5% and liquid water content (LWC) was 0.059 g/m3. Since cloud water deposition on to forest canopies was significantly correlated with the amount of fog water collected, the former parameter could be quantitatively derived from throughfall measurements. Annual cloud water deposition on to Cryptomeria canopies was 1420–2860 mm (Av. 2140 mm), corresponding to 90–180% (Av. 122%) of annual rainfall. The rate of deposition was higher at the mountain ridge and the forest edge than at the mountain side and the forest interior. Annual deposition of SO4 2?, NO3 ?, H+ and NH4 + from cloud water was estimated as 204, 153, 2.5 and 58 kg/ha, respectively, equivalent to 5.8–11.7 times the corresponding deposition via rain. The values are equal to, or exceed, the maximum deposition reported for Appalachian forests in the eastern United States. Multiple regression analyses indicate that cloud water deposition on to Cryptomeria canopies was significantly correlated with the following three parameters: cloud frequency, LWC, and wind speed. Thus, these three factors apparently control cloud water deposition on to forest canopies. 相似文献
992.
993.
Kenji Fujino Mari Obara Hitoshi Kiuchi Hiroshi Shinada Tsutomu Nishimura Toshihiko Maekawa Yuji Hirayama 《Plant Breeding》2020,139(5):845-852
A series of DNA markers for various agronomic traits may accelerate the success of marker-assisted selection in practical plant breeding programmes. Here, we developed DNA markers for the blast resistance gene Pi-cd. In this study, we examined the effects of the Pi-cd locus on not only blast resistance but also agronomic traits in agriculture. We developed three pyramiding lines (PLs) coupling Pi-cd with three blast resistance genes, pi21, Pi35 and Pi39. The effect of Pi-cd on blast resistance was dependent on the coupled resistance genes. Then, we evaluated the effects of Pi-cd on 13 agronomic traits. Amylose content and 1,000-grain weight showed significant differences between the PLs and current commercial varieties, which had no negative effects on agronomic trait values. Furthermore, we investigated the distribution of genotype for the Pi-cd locus among varieties of upland rice. The KT genotype specific to rice blast resistance may be predominant in the varieties. The results suggested that Pi-cd has the potential to be useful for improving blast resistance in rice breeding programmes. 相似文献
994.
Trees are increasingly being planted on the levees of paddy fields of rice (Oryza sativa L.) in northeast Thailand. We investigated and compared the yields of rice grown in rain-fed paddies under and far from canopies of three different tree species: eucalyptus (Eucalyptus spp.), mango (Mangifera indica L.), and the indigenous neem tree (Azadirachta indica A. Juss). Rice yields tended to decrease near trees of all types at five sites, but there was no change in yields at the remaining 11 sites during the 3-year study. The reduced yields likely resulted from lower aboveground biomass, leading to fewer rice panicles and spikelets, particularly near trees with a dense canopy. Extremely low yields were observed near eucalyptus in paddy fields suffering from severe drought. These results, as well as information provided by farmers’, suggest that eucalyptus trees may have detrimental effects on rice and should not be planted on the levees of paddy fields with relatively low productivity. 相似文献
995.
996.
Sonia Demasi Matteo Caser Takashi Handa Nobuo Kobayashi Stefania De Pascale Valentina Scariot 《Euphytica》2017,213(7):148
The growth of evergreen azaleas (Rhododendron spp.) can be altered by iron (Fe) chlorosis when plants are cultivated in a neutral-alkaline substrate. In this study, morphological and physiological responses to alkalinity and Fe deficiency were evaluated in five diploid Japanese azaleas to assess their potential as resources for breeding. R. obtusum ‘Kirin’, R. indicum ‘Shinsen’, R. × pulchrum ‘Sen-e-oomurasaki’, R. indicum ‘Osakazuki’, and R. ripense were pot cultivated in a peat-based substrate for 10 weeks, in acid and alkaline growing media with both adequate and inadequate Fe nutrition. Plant performance was generally affected by high pH of the substrate, while Fe deficiency by itself influenced few of the evaluated parameters, possibly due to the complex adaptive response mechanisms of these slow growing ornamental shrubs. According to the biochemical and physiological variations recorded on a long period of cultivation, R. indicum ‘Osakazuki’ reported the best performance. This azalea could be a valuable resource for breeders. 相似文献
997.
Toshihiko Saito Ikutaro Shimizu Jiro Seki Toshiki Kaga Eiichi Hasegawa Hiromi Saito Kazuya Nagasawa 《Fisheries Science》2010,76(6):909-920
To examine the efficacy of juvenile salmon research as a tool for forecasting adult returns, the results from a study on the
early marine life stage of juvenile chum salmon, conducted in the Nemuro Strait during 1999–2002 (i.e., 1998–2001 brood years),
were compared with the return rates of adult salmon. Among the four brood years, the 2000 brood year (i.e., salmon migrating
to the sea in 2001) was previously reported as showing higher abundance, higher growth rate and better somatic condition during
the coastal residency period. Consequently, we expected it to have the highest return rate, under a hypothesis that juvenile
survival in coastal residency regulates brood-year strength. Contrary to this expectation, the 2000 brood year had almost
the lowest return rate. Alternatively, a statistical model in which sea surface temperature during the first year of marine
life and size at release were utilized as explanatory variables reconstructed the actual variability in return rates more
accurately than that based on the early marine life stage. Possible reasons for the discrepancy between the results of the
juvenile salmon research and adult returns are discussed, and we suggest improvements for future research on juvenile salmon. 相似文献
998.
Kenji Ishihara Chiaki Oyamada Yoko Sato Toshiyuki Suzuki Masaki Kaneniwa Hiromi Kunitake Toshihiko Muraoka 《Fisheries Science》2010,76(6):1015-1021
Glycerol galactoside (GG; floridoside: 2-O-glycerol-α-d-galactopyranoside, and isofloridoside: 1-O-glycerol-α-d-galactopyranoside) is known to be a component of edible red seaweed nori. Recently, we have found that low-quality nori (color-faded
nori), which has a low protein content, contains a large quantity of GG. From further studies, we have also found that GG
has prebiotic characteristics in vitro. In this study, we evaluated the in vivo prebiotic activity of GG in rats. Dietary
GG selectively increased the cecal Bifidobacterium count in rats. Other indices of prebiotics, such as pH of cecal content, organic acid concentrations, and fecal weight, also
supported the existence of prebiotic activity of GG. The present data will also contribute to the development of a new method
of utilizing color-faded nori as a health-promoting foodstuff. 相似文献
999.
Yoshio Kunimune Yasushi Mitsunaga Kazuyoshi Komeyama Masanari Matsuda Toru Kobayashi Tsutomu Takagi Takeshi Yamane 《Fisheries Science》2011,77(4):521-532
Seasonal habitat use by nigorobuna Carassius auratus grandoculis Temminck et Schlegel and gengoroubuna Carassius cuvieri (Temminck et Schlegel) in Lake Biwa was investigated using acoustic telemetry. Twenty-three nigorobuna and 11 gengoroubuna
specimens caught using set-nets in the lake’s south basin were surgically fitted with acoustic transmitters and then released.
Signals from the fishes were recorded by 23 receivers installed around the lake. Between April and June 2007, the first spawning
season after release, signals were received from all tagged fishes. Thereafter, until the second spawning season, signals
were collected from 26 and 45% of released nigorobuna and gengoroubuna individuals, respectively. Seasonal habitat preferences
for these species were studied by distance-based analysis. The analysis revealed that nigorobuna tended to stay near their
spawning area in the south basin of the lake throughout the year, whilst gengoroubuna tended to show a seasonal migration
pattern between the north and south basins. After the spawning season, the latter species migrated to the north basin where
it remained until the next spawning season, when it returned to the south basin. This is the first report of seasonal migration
of nigorobuna and gengoroubuna in Lake Biwa. 相似文献
1000.
Yuuki Kawabata Kimio Asami Masato Kobayashi Taku Sato Koichi Okuzawa Hideaki Yamada Kenzo Yoseda Nobuaki Arai 《Fisheries Science》2011,77(1):79-85
A critical component of many releasing projects is the identification and subsequent implementation of optimal release strategies
that can decrease post-release predation mortalities. We performed laboratory experiments to investigate whether acclimation
to shelters affects the post-release survival of hatchery-reared black-spot tuskfish Choerodon schoenleinii in the presence of a reef-resident predator, the white-streaked grouper Epinephelus ongus. Tuskfish were exposed to groupers under three different experimental conditions/treatments: (1) acclimation of fish to shelters
prior to their exposure to groupers; (2) no acclimation of fish to shelters, but with shelters available during their exposure
to groupers; (3) fish not acclimated to shelters and no shelters available during their exposure to groupers. Tuskfish that
were acclimated to shelters utilized shelters more frequently than did non-acclimated fish, and the survival rate of acclimated
fish was higher than those of fish in the other treatments. These results suggest that pre-release acclimation to shelters
improves the post-release survival of hatchery-reared black-spot tuskfish. 相似文献