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Salt tolerance of five cultivars of Capsicum annuum L. Early Jalapeno, Golden Treasure, NuMex Sweet, NuMex Joe E. Parker, and Santa Fe Grande, two cultivars of C. chinense Jacq. Habanero and Pimienta De Chiera, and one accession of C. annuum, NMCA 10652, were evaluated in a field study. Seedlings were transplanted in late May to field raised beds containing loamy sand soils in a semi-arid environment. Plants were well irrigated throughout the experiment. Three saline solution treatments, prepared by adding NaCl, MgSO4, and CaCl2 to tap water at different amounts to create three salinity levels of 0.82 dS m−1 (control, tap water), 2.5 dS m−1, and 4.1 dS m−1 electrical conductivity (EC), were initiated on 15th June and ended in late August. Among the eight varieties, NMCA 10652 had the highest survival percentage at 100% in the 4.1 dS m−1 treatment, followed by ‘Early Jalapeno’, ‘NuMex Sweet’, ‘Pimienta De Chiera’, ‘Santa Fe Grande’, ‘Golden Treasure’, and ‘NuMex Joe E. Parker’. ‘Habanero’ had the lowest survival at 28%. Compared to control, final shoot dry weight of the plants irrigated with saline solution at 4.1 dS m−1 was reduced by 92% in ‘Habanero’, followed by ‘Golden Treasure’ at 80%. For fruit fresh weight in 4.1 dS m−1 vs. control, ‘Habanero’ had the highest reduction at 86%, followed by ‘Golden Treasure’ at 74%, while NMCA 10652 and ‘Santa Fe Grande’ had the least at 26% and 19%, respectively. NMCA 10652, the most tolerant to salinity, had the lowest leaf Na+ accumulation, while ‘Habanero’, the most sensitive to salinity, had the highest Na+ in the leaves. For leaf Cl, ‘Early Jalapeno’ had the highest, while ‘Habanero’ had the lowest Cl accumulation in the leaves. Generally, sensitive varieties accumulated more Na+ and/or Cl in leaves, except for ‘Early Jalapeno’, which was relatively tolerant to salinity but had high Na+ and Cl accumulation in leaves.  相似文献   
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The aim of the present in vivo study was to monitor real-time fluctuations of cortisol (Cr) in the wall of preovulatory follicles using a microdialysis system (MDS) implanted in the theca layer as well as changes in ovarian venous plasma (OVP) and jugular venous plasma (JVP). Seven cows were superovulated using FSH and prostaglandin F2alpha injections. Dialysis capillary membranes were surgically implanted into the theca layer of mature follicles and connected to a microdialysis system. Fractions of the perfusates were collected from Day -1 (Day 0=LH surge) to Day 3. No difference in the concentrations of Cr between JVP and OVP was detected throughout the experiment. Circulating concentrations of Cr ranged from 20 to 35 ng/ml 8 h after surgery in ovulatory and anovulatory cows. In five ovulatory cows, the Cr concentration decreased to basal levels (<10 ng/ml) between 12 and 24 h after surgery, however, two anovulatory cows retained high Cr levels (>10 ng/ml) up to 42 h after surgery. There was a clear increase in the local concentration of Cr from 13.3+/-2.1 pg/ml at -24 h to 27.5+/-1.7 pg/ml at 0 h (peak of the LH surge) within the wall of ovulatory follicles. This increase was not detected in anovulatory follicles. This transient increase in Cr occurred only in the follicle wall, but not in the OVP or JVP, indicating that the presence of a local regulatory mechanism for Cr production/conversion in ovulatory follicles, and this mechanism may modulate the inflammatory-like reaction induced by LH surge in the follicle wall. The present results demonstrate that the glucocorticoid environment in the follicular wall adjusts at the local level in bovine ovulatory follicles. This mechanism may protect follicles from the adverse effects of glucocorticoid, and it may prevent excess inflammatory reactions associated with ovulation by temporarily increasing local concentrations of glucocorticoid, thus forming an integral part of the regulatory mechanism in ovarian physiology.  相似文献   
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Cows experiencing high levels of inflammation and specific metabolic conditions tend to have slower follicular growth and lower serum and follicular concentrations of oestradiol (E2). Paraoxonase1 (PON1) activity decreases during inflammatory processes. Therefore, the aim of this study was to evaluate the association between serum and intrafollicular (FF) PON1 activity and the serum and intrafollicular levels of E2 and progesterone (P4), as well as the mRNA expression of genes related to steroidogenesis, metabolism and inflammation in the first post‐partum dominant follicle of Holstein cows. No correlation was found between PON1 activity, the expression of the analysed genes and levels of follicular E2 and P4, except for a negative correlation between serum E2 and follicular PO1 activity. Also, no correlation was found between serum and follicular PON1 during the first post‐partum follicular wave.  相似文献   
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