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61.
62.
干旱区制种玉米农田蒸散研究   总被引:2,自引:1,他引:1  
在黑河流域中游的张掖绿洲区建立了大田环境下的制种玉米农田蒸散研究观测点,以气象观测资料为基础,采用波文比能量平衡法(BREB)和参考作物蒸散量作物系数法(ET0Kc)对制种玉米的蒸散进行了计算。结果表明,在一个完整的生长期内,利用波文比能量平衡法得到的蒸散量为513.2 mm,日均3.2 mm/d,用参考作物蒸散量作物系数法得到的作物蒸散量为486.2 mm,日均3.1 mm/d,2种计算方法得到的蒸散量总值差别小。利用波文比能量平衡法所得结果的分析表明,试验地在不同生长阶段,ET变化剧烈,生长初期、发育期、中期、末期分别为2.3、2.9、4.1和3.0 mm/d,其蒸散量分别约占全年蒸散总量的13%、22%、50%和16%。ET月变化显示,4月和5月维持在一个较低水平,平均为2.1-2.3 mm/d;6月剧烈增加到3.6 mm/d;7月达到最大,平均为4.6mm/d;8月蒸散有所降低,为3.3 mm/d;9月,随着作物进入生长末期,蒸散急剧减小到2.8 mm/d。  相似文献   
63.
Cucumber fruits transferred to a warm temperature after chilling displayed various symptoms of chilling-injury. In cucumbers chilled to 0°C, vertical fine wrinkles and/or shallow pitting was observed, while after chilling to 5°C deep pitting and/or surface depressions were apparent. Moreover, in the 0°C fruit compared with 5°C fruit, a higher 210264 mμ UV absorption ratio of leakage substances during chilling was observed. These results suggest that the causes of chilling-injury in the 0°C and 5°C fruit are distinct from one another. Weight loss after chilling, the amount of leakage substances, the exudate content from the cut surface of the fruit, redox potential, titratable acidity and respiratory activity were also checked after periods of chilling of 3 to 15 days.  相似文献   
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65.
The effect of ambient temperature on the true (TME) and apparent metabolisable energy (AME) values of a layer diet was examined using White Leghorn cockerels.

The TME value found at the cool temperature (5 to 15 °C) was significantly higher than those found at hot (25 to 35 °G) and control (22 °C) temperatures. AME values were not significantly affected.  相似文献   

66.
It was recently reported that kokumi substances such as glutathione are perceived through the calcium-sensing receptor (CaSR). In addition, screening by the CaSR assay and sensory evaluation revealed that γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) was a potent kokumi peptide. In this study, the quantities of γ-Glu-Val-Gly in various commercial fish sauces originating from Vietnam (Nuoc Mum), Thailand (Nampra), China (Yu-lu), Korea, Japan (Shottsuru and Ikanago-shoyu), and Italy (Garum) were investigated using a LC/MS/MS method followed by derivatization with 6-aminoquinoyl-N-hydroxysuccinimidyl-carbamate (AQC). The analyses revealed γ-Glu-Val-Gly at concentrations ranging from 0.04 to 1.26 mg/dL, indicating that γ-Glu-Val-Gly is widely distributed among various commercial fish sauces.  相似文献   
67.
Journal of General Plant Pathology - Brown lesions were found on leaves of the weed barnyardgrass in paddy fields in Hiroshima Prefecture in western Japan in June 2017. A fungus, isolated...  相似文献   
68.
The phenylpropanoid glycosides, vanicoside A and B, isolated from rhizomes of giant knotweed (Polygonum sachalinense) showed beta-glucosidase inhibitory activity, with IC(50) values of 59.8 and 48.3 mug/ml (59.9 and 50.5 muM), respectively. In contrast, p-coumaric acid and ferulic acid, corresponding to phenylpropanoyl moieties of vanicosides, exhibited very little inhibition.  相似文献   
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This study assessed the feasibility of using camera image analysis to detect behavioral changes as an indicator of the onset of calving in Japanese Black cattle. Thirty-five pregnant cattle individually housed in pens were used and were continuously monitored using a digital camera system. For the automatic determination of the x and y coordinates of a cow, trajectory analysis was conducted using thermal image and analysis software, and the distances moved were calculated using coordinate data. Further, the frequency of postural changes and the time spent tail raising per hour were measured for 14 cows using visible images. The measurement data were used to calculate hourly data for 12 h prior to amniorrhexis (first rupture of the allantoic sac). The hourly distances moved tended to increase at the time of amniorrhexis, with significantly longer distances measured 3–0 h before amniorrhexis than those at 12–8 h before amniorrhexis (P < 0.05). In all cows, amniorrhexis occurred within 11 h of hourly distances moved by more than 50% compared with distance moved the previous hour. The overall average elapsed time before amniorrhexis was 9 h 30 min (range: 5–11 h). Tail raising time and the frequency of postural changes significantly increased at 1–0 h and 2–0 h before amniorrhexis, respectively. This suggests that predicting the time of calving is possible by measuring the activity of Japanese Black cows during late pregnancy using camera image analysis as a non-invasive technique.  相似文献   
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