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401.
Lamellipodia are thin, veil-like extensions at the edge of cells that contain a dynamic array of actin filaments. We describe an approach for analyzing spatial regulation of actin polymerization and depolymerization in vivo in which we tracked single molecules of actin fused to the green fluorescent protein. Polymerization and the lifetime of actin filaments in lamellipodia were measured with high spatial precision. Basal polymerization and depolymerization occurred throughout lamellipodia with largely constant kinetics, and polymerization was promoted within one micron of the lamellipodium tip. Most of the actin filaments in the lamellipodium were generated by polymerization away from the tip. 相似文献
402.
Varit Srilaong Sukanya Aiamla-or Alisa Soontornwat Masayoshi Shigyo Naoki Yamauchi 《Postharvest Biology and Technology》2011,59(1):110-112
Peel yellowing is a major postharvest problem of lime fruit. Research was conducted to control peel yellowing by UV-B irradiation. Mature green lime fruit were irradiated with UV-B doses at 0 (control), 8.8, and 13.2 kJ m?2 and then stored at 25 °C in darkness. UV-B treatment at 8.8 kJ m?2 efficiently delayed the decrease of chlorophyll content. A high level of chlorophyllide a accumulated in mature green fruit and then gradually decreased with the progress of peel yellowing. The chlorophyllide a level was higher in 8.8 kJ m?2 UV-B-treated fruit than it was in the controls. The pheophorbide a level declined in lime fruit treated with 8.8 kJ m?2 UV-B, especially during the development of yellowing. In addition, the pheophytin a level increased by 8.8 kJ m?2 UV-B treatment at the late period of storage. We concluded that UV-B treatment effectively suppressed chlorophyll degradation in mature green lime during storage, which suggests that UV-B irradiation is a usable method for prolonging the postharvest life of lime fruit. 相似文献
403.
404.
Naoki Murata Seiichi Ohta Atsushi Ishida Mamoru Kanzaki Chongrak Wachirinrat Taksin Artchawakom Hiroyuki Sase 《Journal of Forest Research》2009,14(4):212-220
In several areas in Northeast Thailand, evergreen and deciduous forests coexist under uniform terrain and climatic conditions.
We compared depth and physical properties of soils between evergreen and deciduous forests in the Sakaerat Environmental Research
Station to clarify what factor determines their distribution. The averaged soil depths were 79 ± 27 cm and 135 ± 58 cm in
the deciduous and evergreen forests, respectively. The soils in the deciduous forests were relatively coarser in soil texture
than those in the evergreen forests, particularly in the surface layers. The average available water capacity of the solum
was lower in the deciduous forest soils (78 mm) than in the evergreen forest soils (123 mm). Compared with the evapotranspiration
from the evergreen forest in the study area, the available water capacity of the evergreen forest soil was almost the same
as the water deficit during the dry season (November–February), while that of the deciduous forest soil was lower and insufficient
to maintain the evapotranspiration. These results suggest that the distribution of deciduous and evergreen forests in the
study area was associated with soil water availability, which mainly depends on soil depth. 相似文献
405.
Difference in uprooting resistance among coniferous species planted in soils of volcanic origin 总被引:1,自引:0,他引:1
Akio Koizumi Naoki Oonuma Yoshihisa Sasaki Kunihide Takahashi 《Journal of Forest Research》2007,12(3):237-242
Uprooting resistance against wind force for coniferous plantations in soils of volcanic origin was studied. The difference
in uprooting resistance among Abies sachalinensis, Picea jezoensis, and Larix kaempferi was discussed. The sample site was set in Chitose plantations in Hokkaido Japan, where typhoon 0418 caused fatal uprooting
damage in 2004. An uproot resistance index—the ratio of the geometrical moment of area for uprooted root-plate to the moment
susceptibility to wind force—was defined to quantify relative uprooting resistance against wind force. It was calculated from
the dimensional measurements for the tree forms and root-plates of 100 uprooted sample trees after the typhoon attack. As
a result, the uprooting resistance for Picea jezoensis, which was less damaged among the sample species, was estimated to be greater than those for the other two species. 相似文献
406.
We examined the effect of bark thickness of host trees on the ovipositional success ofSirex nitobei in relation to female body size by analyzing the relationships between female body-weight and ovipositor length and between
bark thickness ofP. densiflora andP. thunbergii trees and oviposition proportion (the proportion of eggs laid to the potential female lifetime fecundity) of the woodwasp.
The ovipositor length ranged from 6 to 14 mm and was correlated positively with the fresh body-weight of females. The bark
thickness of host trees had no significant correlation with the oviposition proportion of large females of more than 100 mg
f.wt, whereas it was correlated negatively with that of small females of less than 100 mg f.wt. Thus,P. densiflora, which has thinner bark as a whole thanP. thunbergii, may be more suitable for oviposition, especially for smaller females.
Research Fellow of the Japan Society for the Promotion of Science.
This study was supported in part by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Science,
Sports, and Culture (No. 80003292). 相似文献
407.
Variations of certain anatomical and mechanical indices within tree stems of aged sugi (Cryptomeria japonica) trees planted in Akita prefecture were studied. The determination of the juvenile/mature wood boundary was also discussed, and the effects of wood structure on mechanical properties were investigated. On the basis of radial and vertical variation of the anatomical and mechanical indices, modulus of elasticity (MOE)/ shear modulus (G) was chosen as the index for determining the juvenile/mature wood boundary. The increase rates of MOE/G at the points of 1%, 2%, and 3% were discussed. It was found that for aged trees, all three points were thought to be effective for dividing juvenile and mature wood. However, for younger trees, the point of 2% was recommended, which was mostly consistent with the result obtained by the increase rate of 1% for tracheid length (TL). Among mechanical properties, the MOE showed more significant juvenile/mature wood differences than did modulus of rupture (MOR) and . By correlation analysis, it was suggested that microfibril angle largely contributed to the indices of MOE and G, and specific gravity largely contributed to the indices of MOR and .Part of this report was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
408.
Naoki Yamanaka Masrom Hasran Dong He Xu Hiroshi Tsunematsu Salma Idris Tomohiro Ban 《Genetic Resources and Crop Evolution》2006,53(5):949-954
We used AFLP analysis to explore the genetic relationship and diversity between and within 4 Mangifera species. We analyzed 35 accessions comprising 8 cultivars and 3 landraces of M. indica L., 11 landraces of M. odorata Griff., 7 landraces of M. foetida Lour., and 6 landraces of M. caesia Jack. Using 8 primer combinations produced a total of 518 bands, 499 (96.3%) of which were polymorphic among the 35 accessions.
Clustering analysis showed that all 35 accessions were basically classified into 4 groups corresponding to the 4 Mangifera species. Our results indicate that the genetic relationship of these 4 Mangifera species based on AFLP analysis is in good agreement with their classification by classic methods. In addition, it was clearly
revealed the genetic diversity between and within 4 Mangifera species. The findings obtained in this study are useful for the breeding in Mangifera species. 相似文献
409.
Mulberry twigs were inserted into the soil as bait to detect Rosellinia necatrix at an early stage of tree infection in the orchard. R. necatrix was frequently trapped on twigs near the trunk base at soil depths of 6–20 cm within 10–20 days in May–July, suggesting that
the incubation period was dependent on soil temperature. Subsequently, we inserted twig in the soil around healthy-looking
trees in naturally infested orchards. R. necatrix was trapped from 80.0% of Japanese pear and 75.0% of apple trees that later proved to be infected. This bait twig method
facilitated quicker diagnosis of white root rot on Japanese pear and apple at early stages of infection and can be used to
detect recurrence of the fungus after fungicide treatment. 相似文献
410.
Shin-ichi Masuzaki Tomoya Miyazaki John A. McCallum Sjaak van Heusden Chris Kik Ken-ichiro Yamashita Yosuke Tashiro Naoki Yamauchi Masayoshi Shigyo 《Scientia Horticulturae》2008
Integration of previously developed Allium cepa linkage maps requires the availability of anchor markers for each of the eight chromosomes of shallot (A. cepa L. common group Aggregatum). To this end, eight RAPD markers originating from our previous research were converted into SCAR markers via cloning and sequencing of RAPD amplicons and designing of 24-mer oligonucleotide primers. Of the eight pairs of SCAR primers, seven resulted in the amplification of single bands of the original RAPDs, and the remaining primer set amplified an additional band. The results of Southern hybridization using RAPD amplicons from genomic DNA of Japanese bunching onion (Allium fistulosum L.)—shallot monosomic addition lines indicated that five SCAR markers were single shallot chromosome-specific markers and were not detected in genomic DNA of A. fistulosum. The eight SCAR primer pairs were applied to other Allium species and exhibited three types of amplification profiles, namely RAPD amplicons observed only in shallot, in shallot and Allium vavilovii, and in several Allium species. A mapping study using 65 F2 plants generated by the selfing of one interspecific cross A. cepa × Allium roylei individual integrated the SCAR marker SAOE17500 into chromosome 5 as expected. The results of the present study show that the eight SCAR primer sets specific to shallot can facilitate the mapping in A. cepa and can also serve as anchor points between maps of different Allium species. 相似文献