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71.
Characterization of plant-derived water extractable organic matter by multiple spectroscopic techniques 总被引:1,自引:0,他引:1
Zhongqi He Jingdong Mao C. Wayne Honeycutt Tsutomu Ohno James F. Hunt Barbara J. Cade-Menun 《Biology and Fertility of Soils》2009,45(6):609-616
Water extractable organic matter (WEOM) derived from fresh- or early-stage decomposing soil amendment materials may play an
important role in the process of organic matter accumulation. In this study, eight WEOM samples extracted with a 40:1 (v/w) water to sample ratio from alfalfa (Medicago sativa L.), corn (Zea mays L.), crimson clover (Trifolium incarnatum L.), hairy vetch (Vicia villosa L.), lupin (Lupinus albus L.), soybean (Glycine max L. Merr.), wheat (Triticum aestivum L.), and dairy manure were investigated using ultraviolet (UV)–visible, Fourier transform infrared (FT-IR), solution 31P nuclear magnetic resonance (NMR), and solid state 13C NMR spectroscopies. UV–visible and FT-IR spectra of the plant-derived WEOM samples were typical for natural organic matter,
but possessed less humic-like characteristics than dairy manure-derived WEOM. Solution 31P NMR spectra indicated that WEOM samples extracted from alfalfa, corn, and soybean shoots contained both orthophosphate and
monoester P. Of the monoester P in WEOM from soybean shoot, 70% was phytate P. WEOM from crimson clover, hairy vetch, lupin,
and wheat shoots contained orthophosphate only. The solid-state 13C NMR spectra of the seven plant-derived WEOM samples indicated that they all were primarily composed of sugars, amino acids
or peptides, and low molecular mass carboxylic acids. Carbohydrates were dominant components with very few aromatics present
in these samples. In addition, WEOM from crimson clover and lupin, but not other three leguminous plant WEOM samples, contained
significant asparagine. On the other hand, WEOM from corn and wheat contained less amino acids or peptides. The spectra of
WEOM of dairy manure revealed the presence of significant amounts of nonprotonated carbons and lignin residues, suggesting
humification of the manure-derived WEOM. Significant carbohydrates as well as aromatics were present in this WEOM. The P and
C bonding information for these WEOM samples may be useful for understanding the effects of WEOM on soil nutrient availability
to plants.
Trade or manufacturers' names mentioned in the paper are for information only and do not constitute endorsement, recommendation,
or exclusion by the USDA-ARS. 相似文献
72.
Studies on the neuroregulatory mechanisms on the secretion of anterior pituitary (AP) hormones in domestic animals are important because nearly all complex physiological and metabolic processes are regulated by the AP hormones. To examine them, this article considers in vivo approaches such as the techniques of intrahypothalamic injection, intracerebroventricular injection, push-pull perfusion, and microdialysis, which have been employed in our own research group for the study in cattle. Also, in vitro approaches such as bovine AP cell culture and the AP explants superfusion system are described. This article clarifies the potential of neuroendocrine study techniques in cattle. 相似文献
73.
Ikue Murata Sigefumi Saruki Katsuyoshi Kubota Sachiko Inoue Naoaki Tashiro Tsutomu Enoki Yasuhiro Utsumi Susumu Inoue 《Journal of Forest Research》2009,14(5):296-301
Effects of sika deer (Cervus nippon) and dwarf bamboo (“sasa;” Sasamorpha borealis) on seedling emergence and survival were investigated in cool-temperate mixed forests in the Kyushu mountain range, Japan.
We compared the effects of sika deer between two sites with different sika deer densities. One site (no-sasa forest) has sparse
cover of S. borealis and a high density of sika deer, and the other site (sasa forest) has dense cover of S. borealis with a low density of sika deer. In the no-sasa forest, more seedlings emerged and the survival rate of the seedlings was
higher compared with the sasa forest. Compared with the sasa forest, the canopy in the no-sasa forest was more open, the organic
layer was shallower and drier, the mean daily soil temperature was higher, and soil temperature fluctuated more widely. Those
environmental parameters did not differ between unfenced and fenced plots. The comparison between the sasa and no-sasa forests
suggested that removal of S. borealis by sika deer had an indirect positive effect on seedling emergence and survival. However, the fenced-plot experiments indicated
that sika deer inhibited seedling emergence and survival. These contradictory conclusions could result from the much larger
negative effects of S. borealis on seedling emergence and survival compared with the effects of sika deer browsing. 相似文献
74.
Distribution and stem growth patterns of mangrove species along the Nakara River in Iriomote Island, Southwestern Japan 总被引:1,自引:0,他引:1
Tsutomu Enoki Moeko Ueda Daisuke Nanki Rempei Suwa Akio Hagihara 《Journal of Forest Research》2009,14(1):51-54
We examined variations in stand structure and tree growth of a mangrove forest along two gradients: from the river mouth to
upper stream and from the riverside to inland, along the Nakara River, Iriomote Island, Japan. Bruguiera gymnorrhiza (L.) Lamk. occurred throughout the intertidal area, though Rhizophora stylosa Griff. and Kandelia candel (L) Druce did not occur upstream. Basal area and maximum tree height of B. gymnorrhiza decreased downstream. The growth rate in stem diameter of B. gymnorrhiza decreased downstream in relation with the soil salinity. The basal area and the maximum tree height of B. gymnorrhiza increased with the distance from the riverside. R. stylosa increased in stem diameter and growth rate toward the riverside. 相似文献
75.
Yasuo Tomida Toshiya Suzuki Tsutomu Yamada Ryuji Asami Hirofumi Yaegashi Yasufumi Iryu Tsuguo Otake 《Fisheries Science》2014,80(2):273-280
We examined differences in otolith oxygen (δ18Ootolith) and carbon (δ13Cotolith) stable isotope ratios between hatchery and wild pink salmon fry. The δ18Ootolith values of hatchery and wild fry were ?7.7 ± 0.2 ‰ and ?8.3 ± 0.3 ‰ (1σ), respectively. This difference reflected differences in temperature conditions experienced by each fry. The δ13Cotolith values of hatchery and wild fry were ?19.2 ± 0.3 ‰ and ?11.1 ± 1.8 ‰ (1σ), respectively. The lower δ13Cotolith values of hatchery fry were probably related to their intake of artificial diets. Discriminant analysis of δ18Ootolith and δ13Cotolith values demonstrated a highly significant difference between hatchery and wild fry with 95.8 % classification accuracy. Therefore, analysis of δ18Ootolith and δ13Cotolith precipitated in the fry stage may be useful for discriminating the origin of returning adult pink salmon. The discrimination method for returning adult fish would provide important information for evaluating the effect of hatchery release and their impact on the wild population. 相似文献
76.
Seiichi Furuya Mai Mochizuki Seiya Saito Hironori Kobayashi Tsutomu Takayanagi Shunji Suzuki 《Pest management science》2010,66(11):1268-1272
BACKGROUND: The increasing occurrence of QoI fungicide resistance in Plasmopara viticola (Berk. & MA Curtis) Berl. & DeToni populations is becoming a serious problem in the control of grapevine downy mildew. In Japan, the existence of QoI‐fungicide‐resistant P. viticola was reported in 2009. RESULTS: The QoI fungicide resistance in P. viticola samples collected from vineyards in Japan in 2008 and 2009 was monitored. Resistant P. viticola were detected in the regions where QoI fungicides have been introduced in accordance with the pest management programme, whereas in Hokkaido vineyards, where QoI fungicides have not yet been introduced, QoI‐fungicide‐resistant P. viticola were not found. CONCLUSION: Japan comprises thousands of islands and is physically isolated from other countries by the sea. Monitoring the emergence, incidence and distribution of QoI fungicide resistance in P. viticola populations in Japan is necessary to improve pest management strategies for downy mildew disease in Japanese vineyards. Copyright © 2010 Society of Chemical Industry 相似文献
77.
Tomomi BAN‐TOKUDA Carole DELAVAUD Yves CHILLIARD Tsutomu FUJIHARA 《Animal Science Journal》2010,81(6):648-656
This experiment was conducted to investigate the difference between ruminal (solid feed, SF) and abomasal (liquid feed, LF) feeding on the plasma leptin concentration in sheep. The experiment consisted of 2 weeks to adapt the animals to SF, 4 weeks of feeding on SF, 2 weeks adaptation to LF, 8 weeks of feeding on LF, 2 weeks of adaptation to SF, and 4 weeks of feeding on SF. The LF directory flowed into the abomasums of sheep by bottle feeding. Plasma leptin concentration before morning feeding was almost constant in the SF periods, whereas it showed between‐day variations when measured during the LF periods. Mean plasma leptin levels were higher for LF (7.77 ± 0.76 ng/mL; mean ± SE) than for SF periods (3.95 ± 0.16 ng/mL; mean ± SE). Although plasma leptin concentration did not show any change after feeding in the SF and LF periods, plasma insulin and glucose levels increased within 15 min after liquid abomasal feeding, but not after solid ruminal feeding. The high plasma leptin concentration during the LF periods in weaned sheep could be due to change of digestible energy intake and changes in plasma insulin and glucose levels accompanying the changes in digestive processes and nutrient supply. 相似文献
78.
Etsuko KASUYA Ken‐ichi YAYOU Tsutomu HASHIZUME Sayuki KITAGAWA Madoka SUTOH 《Animal Science Journal》2010,81(3):345-351
To clarify the role of serotonin (5‐HT) in the regulatory mechanism of L‐tryptophan (TRP)‐induced growth hormone (GH) secretion in cattle, changes in 5‐HT concentrations in the cerebrospinal fluid (CSF) in the third ventricle (3V) and GH in plasma before and after the peripheral infusion of TRP were determined simultaneously. The direct effect of TRP on GH release from the dispersed anterior pituitary cells was also assessed. A chronic cannula was placed in 3V by stereotaxic surgery, then CSF and blood were withdrawn under physiological conditions. TRP (38.5 mg/kg BW) was infused through an intravenous catheter from 12.00 to 14.00 hours and CSF and blood sampling were performed from 11.00 to 18.00 hours at 1‐h intervals. The concentration of 5‐HT in CSF was determined by high‐performance liquid chromatography with electrochemical detection. GH, melatonin (MEL), and cortisol (CORT) concentrations were measured by radio‐immunoassay and enzyme‐immunoassay. Concentrations of 5‐HT were increased by TRP infusion. The TRP infusion significantly increased GH release. On the other hand, TRP did not stimulate GH release from the bovine pituitary cells. MEL and CORT concentrations were not altered by TRP infusion. These results suggest that TRP induced GH release via the activation of serotonergic neurons in cattle. 相似文献
79.
This study aimed to develop a water-extraction system which could produce the fresh water from the air in arid regions and which used renewable energies as the electric power source. In this paper, the experiments for water extraction from the air were carried out by using the novel multi-stage water-extraction device with Peltier deices for two cases of temperature and related humidity of the air. One was the case where the temperature and the related humidity of the air were constant, and the other was the case where they were simulated the variation of the temperature and related humidity of the air in a day of summer and spring in Loess Plateau, China. The effects of the temperature and related humidity of the atmospheric air and supply the electric power to Peltier devices on performance of water production of the device were investigated and reported. 相似文献
80.
Shiro Fukuta Reiko Takahashi Satoru Kuroyanagi Noriyuki Miyake Hirofumi Nagai Hirofumi Suzuki Fujio Hashizume Tomoko Tsuji Hiromi Taguchi Hideki Watanabe Koji Kageyama 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(4):689-701
A loop-mediated isothermal amplification (LAMP) reaction with a primer set designed from the rDNA ITS sequence of P. aphanidermatum was developed. Results of a specificity test using 57 strains of Pythium spp. indicated that the LAMP assay gave no cross reactions in other 39 Pythium species, 11 strains of Phytophthora spp. and eight other soil borne pathogens. The detection limit was 10 fg of genomic DNA, which was ten times the sensitivity of the polymerase chain reaction. The LAMP assay was applied to hydroponic solution samples from tomato fields, and the results were compared to those of the conventional plating method. LAMP was observed to be effective for the specific detection of P. aphanidermatum. Furthermore, P. aphanidermatum was detected directly in tomato roots infected with P. aphanidermatum without DNA extraction. The LAMP method established in this study is a simple, sensitive and rapid tool for the detection of P. aphanidermatum. 相似文献