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91.
The objectives of the present study were to develop a programmable piggyback syringe pump for bovine superovulation and to evaluate the effects of a four-times-a-day injection regimen using the pump. Non-lactating Holstein cows were treated with a total of 30 armour units of porcine FSH by injection four times a day with the pump (study, n = 9) or injection twice a day manually (control, n = 9) for four consecutive days from D10 of the estrous cycle. The pump-driven program successfully induced superovulation in all cows tested. The numbers of small (3– < 5 mm in diameter) and large (≥ 10 mm in diameter) follicles were greater in the study group on D11-13 and D14, respectively. There were fewer unovulated follicles detected on D21 (7 days after estrus) in the study group than in the control group (1.2 ± 0.4 and 3.2 ± 0.6, respectively).  相似文献   
92.
93.
Rice (Oryza sativa L.) can produce black grains as well as white. In black rice, the pericarp of the grain accumulates anthocyanin, which has antioxidant activity and is beneficial to human health. We developed a black rice introgression line in the genetic background of Oryza sativa L. ‘Koshihikari’, which is a leading variety in Japan. We used Oryza sativa L. ‘Hong Xie Nuo’ as the donor parent and backcrossed with ‘Koshihikari’ four times, resulting in a near isogenic line (NIL) for black grains. A whole genome survey of the introgression line using DNA markers suggested that three regions, on chromosomes 1, 3 and 4 are associated with black pigmentation. The locus on chromosome 3 has not been identified previously. A mapping analysis with 546 F2 plants derived from a cross between the black rice NIL and ‘Koshihikari’ was evaluated. The results indicated that all three loci are essential for black pigmentation. We named these loci Kala1, Kala3 and Kala4. The black rice NIL was evaluated for eating quality and general agronomic traits. The eating quality was greatly superior to that of ‘Okunomurasaki’, an existing black rice variety. The isogenicity of the black rice NIL to ‘Koshihikari’ was very high.  相似文献   
94.
Six azaphilones, monascin (1), ankaflavin (2), rubropunctatin (3), monascorburin (4), rubropunctamine (5), and monascorburamine (6), two furanoisophthalides, xanthomonasin A (7) and xanthomonasin B (8), and two amino acids, (+)-monascumic acid (9) and (-)-monascumic acid (10), isolated from the extracts of Monascus pilosus-fermented rice (red-mold rice) were evaluated for their inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice, on the induction of Epstein-Barr virus early antigen (EBV-EA) by TPA in Raji cells, and on the activation of (+/-)-(E)-methyl-2[(E)-hydroxy-imino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitric oxide (NO) donor. Among the compounds tested, seven compounds (1-6 and 10) on TPA-induced inflammation, and six compounds (1, 3-5, 9, and 10) on EBV-EA activation, exhibited potent inhibitory effects. All of the compounds tested showed moderate inhibitory effects on NOR 1 activation.  相似文献   
95.
K. Matsui    M. Yoshida    T. Ban    T. Komatsuda  N. Kawada 《Plant Breeding》2002,121(3):237-240
Two types of male‐sterile cytoplasm, designated msm1 and msm2, in barley were investigated to determine whether these cytoplasms confer resistance to barley yellow mosaic virus (Ba YMV) and Fusarium head blight (FHB). Alloplasmic lines and isogenic lines of two cultivars showed the same reaction to each Ba YMV as that of their euplasmic lines. This demonstrates that the barley male‐sterile cytoplasms msm1 and msm2 have no effect on resistance to BaYMV. No significant difference in reactions to FHB was recognized among fertile alloplasmic lines of ‘Adorra’, but the difference in reactions to FHB between fertile and sterile isogenic lines of ‘Adorra’ was significant. The damage caused by FHB in the male‐sterile lines that produced sterile pollen was significantly greater than the damage in a sterile line that did not produce pollen. These results suggest that pollen or anthers are important factors in infection with or spread of FHB. For production of hybrid seeds, male‐sterile lines with no pollen production, such as those with msm1 male‐sterile cytoplasm, would reduce FHB infestation.  相似文献   
96.
Fusarium head blight (FHB) remains a serious problem that causes yield and grain quality losses, and mycotoxin accumulation in wheat production in western Japan. A 3-year field trial with artificial FHB inoculation was conducted to evaluate varietal characteristics of FHB resistance among 31 wheat cultivars/lines cultivated in western Japan, including one standard line. Severity of FHB, frequency of Fusarium-damaged kernels (FDK), deoxynivalenol concentration (DON), nivalenol concentration (NIV), and grain yield showed significant differences among years and among cultivars/lines. Interaction between years and cultivars/lines was also significant in these traits, but F values were larger for cultivars/lines than for the interaction. Correlation analysis showed that cultivars/lines with lower FHB severities tended to have lower FDK, DON and NIV, and a higher yield. Resistance to kernel infection (RKI), residuals calculated by regressing FDK against FHB severity, and resistance to mycotoxin accumulation (RTA), residuals calculated by regressing DON + NIV against FDK, also differed significantly among cultivars/lines. These results indicated that varietal differences in response to FHB symptom development, RKI and RTA exist among wheat cultivars/lines in western Japan. Such information is important to aid producers in controlling the disease and for breeders to improve FHB resistance and reduce mycotoxin accumulation in commercial wheat cultivars.  相似文献   
97.
Hiba (Thujopsis dolabrata) wood was treated with supercritical carbon dioxide (scCO2) at stepwise temperature increments from 50° to 400°C continuously so that extractives (dichloromethane-soluble and -insoluble phases) and solid residues were obtained. The yield of extractives from hiba wood increased with increasing extraction temperature. The volatile compounds in the dichloromethane-soluble phase from scCO2 extraction at 50°C contained only terpenoids. However, the volatile compounds in the dichloromethane-soluble phase from scCO2 extraction at 300°C not only contained terpenoids but also phenols, furans, hydrocarbons, and organic acids. The yield of β-thujaplicin, which is a useful compound in hiba wood, increased with increasing extraction temperature from 50°C to 300°C; the optimal conditions for extracting β-thujaplicin were 300°C and 19.61 MPa. Further study of degradated compounds from the cellulosic and lignic materials of hiba wood after stepwise high-temperature scCO2 treatment above 300°C may provide clues to its efficient use.  相似文献   
98.
 Isolates of the violet root rot fungus Helicobasidium mompa were collected from herbaceous and tree plants. Their host preference was studied by inoculation experiments using carrots, sweet potatoes, and apple stocks. It was found that sweet potato isolates from Kyushu produced infection cushions on carrots and sweet potatoes but not on apple stocks. Other isolates did not show host preference. Sweet potato isolates were also characterized by ready hyphal mass (sclerotium) production. They were thought to have adapted to the habitat with high disturbance by annual tillage. Received: July 15, 2002 / Accepted: September 26, 2002  相似文献   
99.
Soil erosion in agricultural fields affects not only land productivity but also water environment down stream. Many investigations have been made for the prediction of soil erosion processes. The Universal Soil Loss Equation (USLE) has been applied broadly for the prediction of average annual soil loss from upland fields. However, there are few reports concerning the prediction of nutrient (N, P) losses based on the USLE. Thus, the objective of this study is to propose the prediction equation of nitrogen and phosphorus losses during soil erosion processes on the basis of the USLE. In order to predict total nitrogen and phosphorus losses, the coefficients for total nitrogen or phosphorus transfer are derived on the basis of results from experimental field plots. Three bare-cover USLE plots with different amounts of granular chemical fertilizer were installed in an experimental upland field. There was a tendency for the coefficient of total nitrogen or phosphorus transfer to increase with the average concentration of total nitrogen or phosphorus in the soils. It follows that the more granular chemical fertilizer applied caused a higher coefficient of total nitrogen or phosphorus transfer in the calculations. Moreover, the coefficients in heavily fertilized plots were higher than 1.0. Through this investigation, it became clear that the nutrient losses during soil erosion could be predicted on the basis of the coefficient of total nitrogen or phosphorus transfer along with other soil erosion parameters.  相似文献   
100.
Seasonal changes in multi-scale spatial variation in soil chemical properties, which may be controlled simultaneously by biotic and abiotic factors, have not been studied in tropical dry forests. We evaluated the spatial variation of physico-chemical soil properties, plant litter and terrain attributes at multiple scales in a tropical dry evergreen forest using multivariate geostatistics. Soil samples were collected at different depths using nested interval sampling during 1- and 10-m intervals in both the wet and dry seasons. We measured pH, exchangeable cations (Ex-K+ and Ex-Ca2+), acidity (Ex-H+ and Ex-Al3+), particle size (clay and sand contents), and forest floor mass (Oi and Oa). Pronounced spatial variation in pH was observed in surface soil (0-5 cm) but not in deeper soil (5-55 cm). Multi-scale spatial structures with short (20 m) and long (86 m) ranges were observed in the auto- and cross-variograms of soil, litter and slope gradient. Pronounced multi-scale structures were observed simultaneously in pH and Ex-Ca2+ both in the wet and dry seasons. Only a short-range structure was observed in Ex-K+ and Oa, whereas a long-range structure was pronounced in sand contents and slope gradients. Although the variograms had similar shapes between wet and dry seasons for almost all variables, the short-range structure of the cross-variogram between Oa with pH and base cations was more pronouncedly developed in the wet season than in the dry season. Scale-dependent correlation coefficients suggest that a small-scale spatial variation in pH was connected to heterogeneous litter accumulation via base-cation input, whereas long-range spatial variation was simultaneously linked to particle size and slope gradient. This multivariate geostatistical approach applied within a stand detected biotic and abiotic factors controlling spatial variation in soil properties at both short and long distances.  相似文献   
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