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41.
Glutathione content of in vivo and in vitro matured canine oocytes collected from different reproductive stages 总被引:3,自引:0,他引:3
Kim MK Hossein MS Oh HJ Fibrianto HY Jang G Kim HJ Hong SG Park JE Kang SK Lee BC 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):627-632
Glutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 microm and > 120 microm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 microg/ml estrogen, 0.5 microg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 microM beta-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 microm and > 120 microm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of beta-mercaptoethanol, respectively (P<0.05). Presence of beta-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes. 相似文献
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Field experiment was carried out to investigate the effect of soil matric potential (SMP) on tomato yield, evapotranspiration (ET), water use efficiency (WUE) and irrigation water use efficiency (IWUE) under drip irrigation condition in North China Plain. The experiment included five treatments, which controlled SMP at 0.2 m depth immediately under drip emitter higher than −10 (S1), −20 (S2), −30 (S3), −40 (S4) and −50 kPa (S5), respectively, after tomato plant establishment. The results showed that different SMP affected irrigation amount and tomato ET. Irrigation amount decreased from 185 mm (S1) to 83.6 mm (S5) in 2004, and from 165 mm (S1) to 109 mm (S5) in 2005, respectively. The ET decreased from 270 mm (S1) to 202 mm (S5) in both years. However, it was found that SMP did not affect the tomato yield significantly, for the range of SMP investigated. Both WUE and IWUE increased as SMP decreased. The maximum WUE (253 and 217 kg/ha mm) and IWUE (620 and 406 kg/ha mm) were for S5 in 2 years, whereas the minimum WUE (178 and 155 kg/ha mm) and IWUE 261 and 259 kg/ha mm) were for S1 in 2004 and 2005. Based on the above results, therefore, it is recommended that if the tomatoes are well irrigated (SMP is higher than −20 kPa) during establishment, controlling SMP higher than −50 kPa at 0.2 m depth immediately under drip emitter can be used as an indicator for drip irrigation scheduling during following period of tomato growth in North China Plain. 相似文献
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Fusheng Ma Shaozhong Kang Fusheng Li Jianhua Zhang Taisheng Du Xiaotao Hu Mixia Wang 《Agricultural Water Management》2007,90(3):190-196
The effects of water deficit in different fruit growth stages on the variation of stem sap flux of 6-year old greenhouse-grown pear-jujube trees were investigated. Treatments included sufficient water supply during the whole fruit-growing period (T1), mild water deficit during the flowering–fruit setting stage (T2), moderate water deficit during the fruit rapid growth stage (T3) and severe water deficit during the fruit maturing stage (T4). Results showed that significant compensation effect on stem sap flux after re-watering was observed in T2, but not in T3 and T4 stages. At the end of rapid growth stage, the diurnal variation of stomatal conductance generally had a similar trend as that of stem sap flux, but with a distinct midday depression from 12:00 to 14:00 p.m. In addition, a linear relationship between the relative available soil water content (RAWC) and the ratio of daily stem sap flux to that of sufficient water treatment was observed (R2 = 0.4489). 相似文献
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Drip irrigation scheduling for tomatoes in unheated greenhouses 总被引:5,自引:0,他引:5
During the last two decades, energy-saving solar greenhouses without heating systems, about 150-800 m2 (width: 5-10 m, length: 30-80 m) in size, have been widely used in the North of China for vegetable production during cold seasons. The greenhouse is also suitable for use in other countries located in the temperate or warm-temperate zones, especially in the developing countries, because it is inexpensive with a simple structure, and does not need any additional energy for heating in winter. Drip irrigation has been recognized as a sensible method of supplying water inside the greenhouses, and a simple method for drip irrigation scheduling at low cost is urgently required. Using the water-balance method, the authors studied the water consumption of tomato (Lycopersicon esculentum Mill.) and the relationship between evapotranspiration and water surface evaporation measured with 20 cm pan. Research results show that there is no significant water flux at 0.75 m depth when soil water potential is kept higher than -20 kPa at 15 cm depth, and around -20 kPa at 60 cm depth. The accumulative value of evapotranspiration is approximately equal to the accumulative value of water surface evaporation measured using 20 cm pan. Further analysis found that 20 cm pan can be used to determine the water requirement of tomato drip irrigation scheduling in this type of greenhouse. 相似文献
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介绍了位于环渤海经济圈中心地带的河北省海岸带和海洋经济概况,分析了河北省海洋生物资源的开发利用现状,并从政府管理、生态环境修复、加大海洋科技与教育投入、海洋生物资源摸底调查、海洋渔业产业结构的调整和海洋药用生物资源的开发等六个方面提出了保护和合理利用河北省海洋生物资源的对策,可为海洋生物资源的可持续利用提供参考依据。 相似文献
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以水稻红莲型细胞质雄性不育(HL-CMS)不育系粤泰A(YTA)和保持系粤泰B(YTB)黄化苗线粒体为材料,研究了YTA和YTB离体线粒体KA TP通道对其诱导调节剂KCl、ATP、ADP和GTP等的响应特性。结果表明,KA TP通道诱导剂KCl,能明显诱导YTA和YTB线粒体膨胀,但YTA的膨胀程度较YTB的明显;KA TP通道的内源性抑制剂ATP对YTA和YTB线粒体膨胀起显著抑制作用;KA TP通道的内源性激动剂ADP和GTP引起的不育系YTA离体线粒体短暂收缩及之后的再膨胀程度均较YTB的明显;此外,比较YTA和YTB离体线粒体在Rh123一起孵育10 min后,KCl和解偶联剂FCCP处理引起的离体线粒体膜电位(Δψm)下降过程,发现前者的线粒体Δψm较后者的易于过早崩解。对水稻HL-CMS不育系YTA和可育的保持系YTB线粒体KA TP通道特性的比较研究表明,水稻HL-CMS不育系YTA线粒体KA TP通道对其诱导调节剂KCl、ATP、ADP和GTP等的响应较YTB的更敏感。 相似文献