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71.
Yaohu?KangEmail author Feng-Xin?Wang Hai-Jun?Liu Bao-Zhong?Yuan 《Irrigation Science》2004,23(3):133-143
A field experiment comparing different irrigation frequencies and soil matric potential thresholds on potato evapotranspiration (ET), yield (Y) and water-use efficiency (WUE) was carried out in a loam soil. The experiment included five treatments for soil matric potential: F1 (-15 kPa), F2 (-25 kPa), F3 (-35 kPa), F4 (-45 kPa) and F5 (-55 kPa) and six treatments for irrigation frequency: N1 (once every day), N2 (once every 2 days), N3 (once every 3 days), N4 (once every 4 days), N6 (once every 6 days) and N8 (once every 8 days). Results indicate that both soil matric potential and drip irrigation frequency influenced potato ET, Y and WUE. Potato ET increased as irrigation frequency and soil matric potential increased. Comparing soil water potential, the highest ET was 63.4 mm (32.1%) more than the lowest value. Based on irrigation frequency treatments, the highest ET was 36.7 mm (19.2%) more than the lowest value. Potato Y and WUE were also found to increase as irrigation frequency increased. Potato Y increased with an increase in soil water potential then started to decrease. The highest Y and WUE values were achieved with a soil matric potential threshold of -25 kPa and an irrigation frequency of once a day.Communicated by J. Ayars 相似文献
72.
Toshiyuki Takai Patrick Lumanglas Daisuke Fujita Kazuhiro Sasaki Njato Michael Rakotoarisoa Yasuhiro Tsujimoto Nobuya Kobayashi Eliza Vie Simon 《Breeding Science》2021,71(5):615
The heading date is an important trait for determining regional and climatic adaptability in rice. To expand the adaptability of the indica rice cultivar ‘IR64’, we pyramided multiple early or late heading quantitative trait locus (QTLs) in the ‘IR64’ genetic background by crossing previously developed near-isogenic lines (NILs) with a single QTL for early or late heading. The effects of pyramiding QTLs were observed in three different climatic zones of the Philippines, Madagascar, and Japan. The early heading pyramiding lines (PYLs) headed 6.2 to 12.8 days earlier than ‘IR64’ while the late heading PYLs headed 18.8 to 27.1 days later than ‘IR64’. The PYLs tended to produce low grain yield compared to ‘IR64’. The low yield was not improved by combining SPIKE, which is a QTL that increases the number of spikelets per panicle. Conversely, ‘IR64-PYL(7+10)’ carrying Hd5 and Hd1 headed earlier, produced more tillers, and more panicles per m2 than ‘IR64’, and mitigated the yield decrease in early heading. These results suggest that the effects of pyramided QTLs on heading date were consistent across various environments and PYLs could be used to enhance the adaptation of ‘IR64’ in other rice growing environments. 相似文献
73.
74.
Spake Rebecca Soga Masashi Kawamura Kazuhiro Cooke Robert S. Yamaura Yuichi Eigenbrod Felix 《Landscape Ecology》2020,35(5):1055-1071
Landscape Ecology - Functional responses to landscape heterogeneity are context-dependent, hampering the transferability of landscape-scale conservation initiatives. Japan provides a unique... 相似文献
75.
大豆抗菌核病的全基因组关联研究 总被引:2,自引:0,他引:2
找到大豆与抗菌核病强关联的候选位点或候选基因,为抗病基因克隆和抗病分子标记开发提供借鉴,服务大豆抗菌核病育种。对126个加拿大大豆品种的基因组DNA用ApekⅠ酶消化后Illumina Hiseq2000平台测序进行基因分型,供试的126个材料用棉垫接种核盘菌菌丝体进行表型鉴定。采用Structure 2.3.4、SPSS 20.0、TASSEL 5.0和PLINKv 1.07软件分别模拟群体遗传结构、二元主成分分析、邻接法聚类,进行SNP-phenotype和Haplotype-phenotype的关联分析(只考虑加性效应)。最小等位基因频率0.01过滤,得到30 125个SNPs。主成分及群体结构聚类结果中度一致,将126个供试材料划分为2个组群,Kappa聚类一致度检验K=0.44。邻接法(The neighbor-joining algorithm,NJ)聚为3个组群。α≤0.05时,在单个SNP-phenotype的关联研究中,最强关联在3号染色体物理位置34387780、34387823和34387841处(P值都为8.669E-7),可分别解释表型变异的17.80%,其次在20,1,4,17号染色体上。Haplotype-phenotype的关联分析中,最强关联在17号染色体物理位置5575883/5647814/5648648/5734897处(P值为1.038E-6),可解释表型变异的17.56%。200 kb范围内,3号染色体上的候选基因有Glma.03g129100、Glma.03g129200、Glma.03g129300、Glma.03g129500、Glma.03g129800、Glma.03g129900。17号染色体上为Glma.17g071300、Glma.17g072200、Glma.17g073300。 相似文献
76.
Kazufumi?OsakoEmail author Mohammed?Anwar?Hossain Koichi?Kuwahara Akira?Okamoto Atsuko?Yamaguchi Yukinori?Nozaki 《Fisheries Science》2005,71(6):1347-1355
ABSTRACT: To explore the potential utility of underutilized fish in the fish sauce industry, fish sauces were prepared from both raw and heat-induced meat of Japanese anchovy Engraulis japonica and rabbit fish Siganus fuscescens using wheat malt, and their quality aspects and sensory properties were assessed. Proximate composition of the fish meat represents protein as the major component (16.0–17.8%), other than moisture. Analyses of free amino acids, peptides including oligopeptides, and organic acids contents in fish sauces revealed suitability of both raw and heat-induced meat of the selected species in commercial fish sauce production. The variations in taste of raw meat fish sauces were species-specific, but the taste of fish sauces from heat-induced meat were similar. 相似文献
77.
Kazuhiro Shiozaki Momo Shiozaki Junko Masuda Akiko Yamauchi Shuichi Ohwada Toshiki Nakano Toshiyasu Yamaguchi Tadao Saito Koji Muramoto Minoru Sato 《Fisheries Science》2010,76(5):865-872
Angiotensin-I-converting enzyme (ACE) plays a crucial role in the crisis of hypertension. Some peptides that originate from
protease hydrolysates are known to suppress ACE activity in vitro and in vivo. Here, we investigated whether trypsin hydrolysate
of oyster Crassostrea gigas showed hypotensive activity and ACE inhibition. The hydrolysate significantly suppressed systolic blood pressure and ACE
activity in spontaneously hypertensive rats following a one-shot oral administration and a long-term feeding experiment lasting
9 weeks. Each hydrolysate from oyster tissue showed ACE inhibitory activity, indicating the hypotensive effect was due to
synergism. One potent ACE inhibitory peptide, Asp-Leu-Thr-Asp-Tyr, was identified from the hydrolysate of the striate muscle,
and the peptide exhibited hypotensive activity in vivo. Protease digestion analysis suggested that Asp-Tyr could be the real
effector of this penta-peptide in vivo. 相似文献
78.
ABSTRACT: The effects caused by suspended particles in seawater and sediment cover of the substrate on the attachment to the substrate of zoospores, and on the subsequent growth and survival of gametophytes of the brown alga Eisenia bicyclis were examined in the laboratory. The attachment rate to the substrate of the zoospores was remarkably reduced by the sediment cover on the substrate, and it decreased to 3.8% of the no-sediment control by a slight sediment cover of 3.0 mg/cm2 (0.048 mm in thickness). The growth of gametophytes was not inhibited at 10 mg/cm2 or less of sediment cover, though it was stopped at 30 mg/cm2 . The survival rate of gametophytes became 39.4% at 5 mg/cm2 on the substrate, and gametophytes were all blighted at 30 mg/cm2 . The ratio of male to female of the surviving gametophytes became 81.5:18.5, when the sediment cover was 10 mg/cm2 . The rate of total loss ( TL [%]) of zoospores and gametophytes of Eisenia bicyclis was obtained from the following equation: TL = 100 (1 − exp[−0.0339 C ] exp[−1.24 Q ]), where, C (mg/L) and Q (mg/cm2 ) indicate the concentration of suspended particles in seawater and the sediment on the substrate, respectively. 相似文献
79.
Pedro ?M.?DominguesEmail author Paul?F. ?Dimarco Jose? P.?Andrade Phillip?G.?Lee 《Aquaculture International》2005,13(5):423-440
The effects of artificial diets on growth and body condition of adult cuttlefish, Sepia officinalis were tested in two experiments. Supplemented prepared diets (fish myofibrillar protein concentrate) were fed during a 30-day and a 21-day experiments. Growth, feeding rate and food conversion of group-reared cuttlefish were analyzed. The first of these experiments tested four artificial diets, made with increasing levels of lysine, on adult cuttlefish. According to the chemical analysis, diets 1–3 had limiting concentrations of lysine and other essential amino acids (compared to mantle composition of the cuttlefish), while diet 4 was the only one where almost all essential amino acids were present in concentrations similar or higher than the ones present in cuttlefish mantle. A second experiment was conducted by isolating 16 adult cuttlefish individually, and feeding them the same four artificial diets, in order to obtain individual data. During Experiment 1, only the diet with the best chemical score (diet 4) produced growth (p < 0.05), with a mean instantaneous growth rate (MIGR) of 0.30% wet body weight (BW) d−1. Similarly, individually reared cuttlefish fed diet 4 produced the highest IGR’s (0.26, 0.38 and 0.48% BW d−1) and grew larger (p < 0.01). Comparison of cuttlefish fed the artificial diets vs. thawed shrimp and unfed cuttlefish indicated that cuttlefish fed the artificial diets were in an intermediate state. Growth rates obtained with the artificial diets (<0.4% BW d−1) were considerably lower compared to natural prey, live or frozen, reported by other authors. 相似文献
80.
Mercedes Alonso Fátima C. Lago Juan M. Vieites Montserrat Espi?eira 《Aquaculture International》2012,20(5):847-857
Microalgae are the main component of first tropic level in aquatic food chain; it is for this reason that they are used as food in aquaculture. Also due to its biotechnological potential properties, they are used in the production of diverse components, dyes, antioxidants, enzymes, emulsifiers, etc. The extended ways of microalgae applications require physiologically and genetically stable cultures as well as correctly identified organisms to guarantee reproducibility and reliability. But the variety of species and the morphological similarity between some of them make difficult the identification of some microalgae. The use of molecular markers has supplied a very useful tool for identification of microalgae in fast mode, such as in classification. The present study has worked on the molecular characterization of main species of microalgae used in aquaculture in base of the molecular markers 18S rRNA and 16S rRNA. Microalgae DNA has been amplified and sequenced, and the resultant sequences were analyzed and reflected in phylogenetic trees. The phylogenetic analyses obtained reflect as both molecular markers allow to differentiate the main genus used in aquaculture. 相似文献