The treated seeds (control, KNO3 and hydropriming) of sunflower (Helianthus annuus L.) cultivar Sanbro were evaluated at germination and seedling growth for tolerance to salt (NaCl) and drought conditions induced by PEG-6000 at the same water potentials of 0.0, −0.3, −0.6, −0.9 and −1.2 MPa. Electrical conductivity (EC) values of the NaCl solutions were 0.0, 6.5, 12.7, 18.4 and 23.5 dS m−1, respectively. The objective of the study was to determine factors responsible for germination and early seedling growth due to salt toxicity or osmotic effect and to optimize the best priming treatment for these stress conditions.
Results revealed that germination delayed in both solutions, having variable germination with different priming treatments. Germination, root and shoot length were higher but mean germination time and abnormal germination percentage were lower in NaCl than PEG at the same water potential. Seeds were able to germinate at all concentrations of NaCl but no seed germination was observed at −1.2 MPa of PEG treatments. NaCl had less inhibitor effect on seedling growth than the germination. It was concluded that inhibition of germination at the same water potential of NaCl and PEG resulted from osmotic effect rather than salt toxicity. Hydropriming increased germination and seedling growth under salt and drought stresses. 相似文献
This research investigated the proximate chemical composition of whiting roe from October to April. The highest water content (83.99%) was found in March, while the lowest (72.40%) was found in December. The highest protein (14.54%) and lipid contents (9.71%) were found in December, while the lowest protein content (7.35%) was found in January and the lowest lipid content (0.38%) in April. Crude ash content of whiting roe changed from 0.86 to 1.49%. The highest (154 kcal/100 g) and lowest energy values (64 kcal/100 g) were determined in December and April, respectively. Whiting roe can be used as a source of valuable nutrients for human nutrition. 相似文献
Mating system parameters and pollen contamination were estimated in an 11-year-old Pinus brutia Ten. clonal seed orchard, located in Antalya, Turkey, with the aid of isozymes. Isozyme analysis was performed on both maternal
(megagametophyte) and embryo tissues of seeds collected from the seed orchard and the surrounding natural stand. Fourteen
loci encoding nine enzyme systems were assayed. Based on a multilocus estimator, the proportion of viable seeds originating
from outcrossing (tˆm) in the seed orchard was found to be 0.947; the remainder (0.053) was due to selfing. We estimated that 85.7% of the orchard
seed resulted from pollen contamination by trees in surrounding stands. This may be related to the young age and subsequent
low pollen production of the orchard. Only 9% [i.e., 1.0−0.857 (contamination)−0.053 (selfing) = 0.090] of the orchard offspring
was due to cross-pollination among clones within the orchard. Due to the high level of pollen contamination, it is estimated
that genetic gain in this seed crop is less than 57% of that expected if all offspring resulted from random mating among orchard
clones (i.e., no contamination). 相似文献
A total of 35 Escherichia coli isolates obtained from necropsy materials of hens with septicemia in the Konya region of Turkey were examined for hemagglutination (HA), cell-surface hydrophobicity, enterotoxigenicity, and drug resistance. HA tests were performed on live cultures with human (group A), bovine, avian (chicken), and guinea pig erythrocytes with and without mannose. Nine HA patterns were observed. Of the 35 isolates, 62.8% exhibited mannose sensitive hemagglutination (MSHA), 8.6% exhibited mannose resistant hemagglutination (MRHA), and 28.6% did not hemagglutinate. Of the isolates, 85.7% were hydrophobic by a salt aggregation test (SAT). Only three isolates were enterotoxigenic by a suckling mouse assay. The majority of the isolates were resistant to chloramphenicol, tetracycline, streptomycin, ampicillin, erythromycin, and trimethoprim + sulfamethoxazole but were highly sensitive to gentamicin and nalidixic acid. 相似文献
This study evaluated the survival and recovery of non-encapsulated and encapsulated shoots of Sequoia sempervirens after storage at 4 °C in the dark for up to 15 months on four different culture media. Survival and regrowth of encapsulated shoots declined within 3 months, regardless of the storage medium composition. By contrast, no significant decrease in survival and regrowth was noted with non-encapsulated shoots after 12 months of storage on Quoirin and Lepoivre medium supplemented, or not, with 1 mg l−1 benzyladenine. Regrowth dropped to 60–61% after 15 months of storage on the same media. Medium-term conservation of S. sempervirens germplasm is therefore possible using in vitro storage of non-encapsulated shoot cultures. 相似文献
The effect of supplementary phosphorus on growth and yield of tomato (Lycopersicon esculentum cv. Target F1) plants grown at high boron was investigated. The results showed that high B reduced dry matter, fruit yield and chlorophyll content. High B plus 0.5 or 1 mM P increased plant dry matter, fruit yield and chlorophyll concentrations as compared to high B treatments only. Membrane permeability was not increased significantly due to high B application. In the leaves of plants grown at high boron treatments, superoxide dismutase (SOD), peroxidase (POD) and polyphenol oxidase (PPO) levels were increased. However, supplementary P to nutrient solution containing high B reduced the activities of the earlier mentioned enzymes in leaves but their levels were still higher than those at the control treatments. The study revealed that B status affects the activities of some antioxidant enzymes examined. Boron (B) concentrations increased in leaves and roots in the highest external B treatment as compared to the control treatment. Concentrations of Ca, P and K were significantly lower in the leaves of plants grown at high B than those in the control plants. Supplemented nutrient solution containing high B with 0.5 or 1 mM P increased the tissue concentrations of nutrients. These results indicate that supplementary P can mitigate the adverse effects of high B on fruit yield and growth in tomato plants. 相似文献
Journal of Pest Science - The larvae of Curculio elephas (Coleoptera: Curculionidae) and Polyphylla fullo (Coleoptera: Scarabaeidae) are major agricultural pests of chestnut and roots of cultivated... 相似文献
The serotonergic regulation of feeding behaviour has not so far been studied in ruminants. Therefore, the effects of some serotonin (5-HT) receptor agonists and antagonists on food intake and forestomach motility were studied in dwarf goats.Goats ate less food when treated intravenously (IV) with the 5-HT precursor 5-HTP (25 µg, 50 µg or 100 µg kg–1 min–1 over 15 min) than when they were treated with 5-HT (which does not pass the blood-brain barrier) or with saline. Accordingly, IV dexfenfluramine infusions (50 µg or 100 µg kg–1 min–1 over 15 min), which induces release of brain 5-HT, also led to dose-related reductions in food intake. In contrast, no anorectic effects were observed after IV infusions with the selective 5-HT reuptake inhibitor fluoxetine (100 µg kg–1 min–1 over 15 min), the selective 5-HT1A agonist 8-OH-DPAT (0.5 µg kg–1 min–1 over 15 min), or eltoprazine (4 or 8 µg kg–1 min–1 over 15 min), a mixed 5-HT1A/5HT1B receptor agonist. None of the 5-HT antagonists tested gave any increase in food consumption in this model. Interestingly, the non-selective 5-HT receptor antagonist methysergide (360 µg/kg IV) reduced food intake. This effect was most noticeable at 3 h after injection. The 5-HT3 receptor antagonist ondansetron (IV 10 µg kg–1 min–1 over 15 min) and the peripheral 5-HT2 receptor antagonist xylamidine (IV 100 µg kg–1 min–1 over 10 min) failed to modify food intake. These results provide evidence for central serotonergic involvement in the control of feeding. However, this control system differs markedly in goats and rodents.Dexfenfluramine, 5-HTP and eltoprazine administered at similar dose rates to those used in the food intake experiments induced some clinical signs including inhibition of forestomach contractions. These results, together with our earlierin vivo andin vitro observations, suggest that the inhibitory effects of serotonin receptor agonists on forestomach contractions are due to interactions with both peripheral and central serotonergic receptors. The change in smooth muscle tension, which leads to a change in the signals transmitted via vagal afferents to the central nervous system, appears not to modify feeding behaviour in dwarf goats. 相似文献
Cell-to-cell interaction via cell contact-dependent pathway is essentially important for maintenance and regulation of corpus luteum (CL) integrity and its physiological actions. The objective of the present study was to evaluate the mRNA expression of the cell adhesion molecules (CAMs) that are constituent factors of gap junctions [connexin (Cx) 43] and adherence junctions (VE-, E-, N-cadherin) in two types of endothelial cells from the mid CL and in CL tissue during the estrous cycle and PGF(2alpha)-induced luteolysis in the cow. Specific mRNA expression for Cx43 and N-cadherin was detected in cytokeratin-positive (CK+) and cytokeratin-negative (CK-) luteal endothelial cells (EC) and fully luteinized granulosa cells (LGC). E-cadherin mRNA was expressed in CK+EC and LGC, but not in CK-EC. VE-cadherin mRNA was expressed in both CK+ and CK-EC. During the estrous cycle, Cx43 mRNA expression was significantly lower in the regressing CL. VE-cadherin expression also tended to increase in the mid CL and increased significantly in the regressing CL. E-cadherin mRNA expression was higher in the early and late CL than in the mid- and regressing CL. N-cadherin mRNA expression gradually increased from the early to late CL followed by a decrease in the regressing CL. During PGF(2alpha)-induced luteolysis, Cx43 mRNA expression appeared to increase, and VE-cadherin and E-cadherin mRNA significantly increased at 24 h. N-cadherin mRNA expression decreased 2 and 4 h after PGF(2alpha) administration. Collectively, expression of the mRNAs for CAMs was different in the two types of luteal endothelial cells and fully luteinized granulosa cells and changed independently in the CL during the estrous cycle and PGF(2alpha)-induced luteolysis in the cow. The results suggest that CAMs play physiological roles in cell-to-cell communication to regulate both gap and adherence junctions during CL development and regression in the cow. 相似文献