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101.
CH4 production in a flooded soil as affected by elevated atmospheric CO2 was quantified in a laboratory incubation study. CH4 production in the flooded soil increased by 19.6%, 28.2%, and 33.4% after a 2-week incubation and by 38.2%, 62.4%, and 43.0%
after a 3-week incubation under atmospheres of 498, 820, and 1050 μl l–1 CO2, respectively, over that in soil under the ambient CO2 concentration. CH4 production in slurry under 690, 920, and 1150 μl l–1 CO2 increased by 2.7%, 5.5%, and 5.0%, respectively, after a 3-day incubation, and by 6.7%, 12.8%, and 5.4%, respectively, after
a 6-day incubation over that in slurry under the ambient CO2 concentration. The increase in CH4 production in the soil slurry under elevated CO2 concentrations in a N2 atmosphere was more pronounced than that under elevated CO2 concentrations in air. These data suggested that elevated atmospheric CO2 concentrations could promote methanogenic activity in flooded soil.
Received: 2 March 1998 相似文献
102.
小菜蛾对4种农药抗药性的研究 总被引:4,自引:0,他引:4
用浸叶法测定了日本关西地区小菜蛾幼虫对乙酰甲胺磷、巴丹、氯氰菊酯和Bt4种不同类型农药的抗药性。试验明确小菜蛾在当地对上述4种参试农药都已产生不同程度抗药性。小菜蛾R系幼虫在240mg/kg氯氰菊酯、200μl/LBt浓度下死亡率分别仅为3.7%、7.2%。这两种农药目前已不能用于防治日本关西地区菜田小菜蛾 相似文献
103.
Kumiko Hayashi Kunihiko Konno Kyoko Adachi Takeshi Nawamura Yoshikazu Shizuri Yuji Okita Ikuo Kimura 《Fisheries Science》2009,75(3):797-803
Suppressive effects of neocarrabiose 4-O-sulfate on the thermal and freeze denaturation of myosin subfragment-1 (S-1) and on myofibrils were investigated. The compound
strongly suppressed the thermal denaturation of S-1. Its suppressive effect was greater than that of sorbitol and similar
to that of maltose. However, it tended to accelerate the denaturation of myofibrils, suggesting a loss of protection by F-actin
upon its addition. The compound suppressed the freeze denaturation of myofibrils and S-1. The effect was similar to that of
sorbitol or maltose, and completely different from that of Na-sulfate. The compound solubilized myofibrils at concentrations
similar to KCl. Therefore, it was concluded that neocarrabiose 4-O-sulfate behaved as an ionic salt in the thermal treatment process, whereas it behaved as a sugar in the frozen storage process. 相似文献
104.
Spawning induction and seed production of Eastern little tuna,Euthynnus affinis (Cantor, 1849), in the post‐ and pre‐spawning seasons by hormonal treatment in a semi‐closed recirculation system with elevated temperature 下载免费PDF全文
Ryosuke Yazawa Yutaka Takeuchi Kenta Satoh Yuri Machida Kotaro Amezawa Naoki Kabeya Goro Yoshizaki 《Aquaculture Research》2017,48(7):3472-3481
We previously established a method for spawning induction in Eastern little tuna (ELT) Euthynnus affinis (Cantor, 1849) by administering a gonadotropin‐releasing hormone analog (GnRHa) during the natural spawning season in Japan (August–October). In order to establish seed production of ELT in the off‐spawning season, we first conducted three spawning induction trials by GnRHa administration from October 2011 to January 2012 using ELT broodstock (2 years old; three females and four males) maintained in a 10‐m3 tank with a semi‐closed recirculation system and static elevated temperature. Average water temperature and daily egg production in three trials lasting 11–15 days were 27.0 ± 0.09°C and 268 173 eggs (Trial 1), 27.0 ± 0.11°C and 277 9098 eggs (Trial 2), and 25.5 ± 0.39°C and 291 113 eggs (Trial 3) respectively. Mean fertilization rate and mean hatching rate were 70.4% and 60.5% (Trial 1), 83.9% and 79.6% (Trial 2), and 62.5% and 57.4% (Trial 3) respectively. We also succeeded in producing ELT larvae in the pre‐spawning season (April–July), although the quantity and quality of larvae produced were inferior to those produced in other calendar months. In trials involving periodic GnRHa administration during the off‐spawning seasons, hatched larvae were obtained in the 10‐m3 tank after six of nine administrations in the 2011–2012 off‐spawning season and in 16 of 19 administrations in the 2012–2013 off‐spawning season. The findings of this study demonstrated that hormonal treatment and thermal control could be used to extend the spawning period in ELT, potentially allowing larval production in the post‐ and pre‐spawning seasons. 相似文献
105.
Ryusuke Sudo Ryota Tosaka Shigeho Ijiri Shinji Adachi Hiroaki Suetake Yuzuru Suzuki Noriyuki Horie Satoru Tanaka Jun Aoyama Katsumi Tsukamoto 《Fisheries Science》2011,77(4):575-582
To improve understanding of the mechanism of early ovarian development in eels, the effects of water temperature decrease
on oocyte development, plasma levels of sex steroids [estradiol 17β (E2), testosterone (T), 11-ketotestosterone (11-KT)],
and gonadotropin β-subunit [follicle-stimulating hormone (FSHβ), luteinizing hormone (LHβ)] messenger RNA (mRNA) expression
levels were investigated. A total of 27 female Japanese eels Anguilla japonica were divided into initial, control, and test (water temperature decrease) groups. Starting on 22 September 2009, eels in
the test group were reared in a tank with gradual temperature decrease from 25°C to 15°C over 39 days, while the control group
was maintained at 25°C. The test group accumulated more oil droplets in their oocytes than did the other groups. Levels of
sex steroids, especially 11-KT, were higher in the test group. In contrast, FSHβ and LHβ mRNA expression levels were lower
in the test group. These results suggest that water temperature decrease only induced an early stage of ovarian development
that was partly affected by an 11-KT increase. For further maturation, other environmental factors related to induction of
gonadotropin increase appear to be needed. 相似文献
106.
Takuya Wada Hiyori Monden Sachiko Isobe Kenta Shirasawa Takayuki Sueyoshi Chiharu Hirata Miyuki Mori Shiro Nagamatsu Yoshiki Tanaka 《Breeding Science》2021,71(4):456
Male sterility is one of the reproductive isolation systems in plants and quite useful for F1 seed production. We previously identified three independent quantitative trait loci (QTLs) for male sterility of cultivated strawberry, Here, we identified the specific subgenomes in which these QTLs are located by QTL-seq approach. QTLs qMS4.1, qMS4.2, and qMS4.3 were mapped separately in subgenomes Fvb4-4, Fvb4-3, and Fvb4-1, respectively, in ‘Camarosa’ genome assembly v. 1.0.a1. Candidate regions of qMS4.1 and qMS4.3 were clearly detected around 12–26 Mb in Fvb4-4 and 12–14 Mb in Fvb4-1, respectively; those of qMS4.2 were fragmented in Fvb4-3, which suggests that some scaffolds were incorrectly assembled in Fvb4-3. qMS4.3 was mapped to chr4X1 of ‘Reikou’ genome assembly r2.3, and qMS4.1 and qMS4.2 were both mapped to chr4Av, which indicates that differentiation of the subgenomes in which both QTLs are located was insufficient in ‘Reikou’ r2.3. Although ‘Camarosa’ genome assembly v. 1.0.a1 is an unphased map, which merges homologous chromosomes into one sequence, ‘Reikou’ genome assembly r2.3 is a phased map, which separates homologous chromosomes. QTL mapping to different reference genomes clearly showed the specific features of each reference genome, and that using different kinds of reference map could accelerate fine mapping and map-based cloning of certain genes of cultivated strawberry. 相似文献
107.
Marker‐assisted backcrossing to develop foliar disease‐resistant genotypes in TMV 2 variety of peanut (Arachis hypogaea L.) 下载免费PDF全文
Rohini M. Kolekar Mallenahally Sukruth Kenta Shirasawa Hajisaheb L. Nadaf Babu N. Motagi Sattigarahalli Lingaraju Prakashgouda V. Patil Ramesh S. Bhat 《Plant Breeding》2017,136(6):948-953
TMV 2 is a very popular peanut variety among the Indian farmers, but it is highly susceptible to fungal foliar diseases like late leaf spot (LLS) and rust. Marker‐assisted backcrossing (MABC) in TMV 2 using foliar disease‐resistant donor, GPBD 4 and the disease resistance‐linked markers (GM2009, GM2079, GM2301, GM1839 and IPAHM103) resulted in a large number of backcross populations and also straight cross populations. Foreground selection followed by field evaluation under disease epiphytotic conditions could identify a few superior genotypes. Two homozygous backcross lines TMG‐29 and TMG‐46 showed enhanced resistance to LLS and rust diseases (score of 3.00 for both) along with 71.0% and 62.7% increase in the pod yield per plot, respectively, over the check, TMV 2. These foliar disease‐resistant and productive lines can be released as commercial varieties or can be used as genetic resources in the peanut improvement. 相似文献
108.
109.
110.
The deterioration of particleboards for construction use was investigated by outdoor exposure tests at eight sites in Japan over 7 years. Two types of particleboard with different water resistances were tested and the deterioration of mechanical properties such as modulus of rupture, internal bond strength and lateral nail resistance was investigated. In order to eliminate regional differences in the board deterioration and also to standardize a deterioration factor for the board exposed to varying climate conditions, we introduced the weathering intensity (WI) defined by monthly precipitation multiplied by monthly average temperature. The significance of this factor was investigated by correlation analysis. Three conventional climate indexes relevant to the durability of wood were also investigated to analyze their significance to WI for particleboard deterioration. It was found that our definition of weathering intensity was the most accurate and the exposure period that reduces initial bending strength by half was calculated by the use of regression analysis for several different sites worldwide. 相似文献