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71.
Larvae of the cereal leaf minerSyringopais temperatella Led. (Lep.: Scythridae) collected from wheat and barley fields in the southeast Anatolian region of Turkey during 2005–2006, and their parasitization rates, were determined in the laboratory,Bracon (Habrobracon) stabilis Wesmael andApanteles sp. (Hymenoptera: Braconidae) were identified as its parasitoids for the first time.  相似文献   
72.
This study examined an offshore submerged mussel longline system, in the Black Sea, from May 2009 to May 2010. The system was allowed 1 year for spat collection. After a 1‐year spat collection period, some spat collectors were left untouched (NS), and some spat collectors were grazed and socked (S) for a grow‐out study in May 2009. The effects of stocking density on the growth and survival of the S and NS mussels were examined. The biochemical composition of the mussels was also determined. Environmental factors including temperature, salinity, chlorophyll a, total suspended matter, inorganic matter and organic matter were monitored monthly during the experimental period. In May 2010, the mean length and live weight of the S and NS mussels were 60.46 ± 0.60 mm and 53.34 ± 0.37 mm, respectively, and 20.50 ± 0.50 g and 13.11 ± 0.26 g respectively. Mean moisture and ash were 82.35 ± 0.47% and 6.67 ± 0.44% respectively. Mean carbohydrate, protein and lipid were 27.74 ± 2.40%, 57.68 ± 2.15% and 7.91 ± 0.68% respectively. These results indicate that a submerged offshore mussel culture system in the Black Sea can be commercially convenient. In addition, stock management via thinning out of the spat can considerably increase the marketable size of mussels, reduce harvest time and produce better growth.  相似文献   
73.
In this study was evaluated potential protective effect of organic selenium (Se) on heavy metal stress induced by lead (Pb) in Cyprinus carpio. For this reason, C. carpio was exposed to sublethal concentration of Pb (1.5 mg/L Pb(NO3)2) for 14 days. The fish were fed a basal (control; measured 0.55 mg/kg Se) diet or a basal diet supplemented with 2.50 mg/kg (measured 2.92 mg/kg Se) organic Se (Sel-Plex®) during the experiment period. The variations in glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) activities, and levels of reduced glutathione (GSH) with malondialdehyde (MDA) in liver and brain tissues of C. carpio were investigated in experimental groups. GSH levels in liver and brain tissues were significantly decreased by exposure to Pb. GST activity was significantly increased (p < 0.05) in liver tissue, but decreased in brain of treated fish by exposure to Pb. Also, GSH-Px activity was significantly increased in liver tissue, but decreased in brain of Pb-treated fish. Levels of MDA were increased in liver and brain of Pb-treated fish. The organic Se treatment for Pb-intoxicated animals improved activities of GSH-Px, GST and levels of MDA within normal limits. Supplemented Se could be able to improve Pb-induced oxidative stress by decreasing lipid peroxidation and regulating antioxidant defense system in tissues.  相似文献   
74.
The objective of this study was to evaluate the effects of seven nitrogen (N2)-fixing and/or phosphorus (P)-solubilizing and siderophore-producing microorganism based bio-fertilizers in single and triple strain combinations isolated from the acidic rhizospheric soil of native tea, grapevine, and wild red raspberries. As a result of this study, bacterial efficiency was found to be variable and depended on the bacterial strains and evaluated growth parameters. Plant growth-promoting rhizobacteria (PGPR) has improved macro- and micro-nutrient concentrations in grapevine leaves, and stimulated plant growth. Triple inoculation and single inoculation based bio fertilizers were found to stimulate overall plant growth, including shoot and leaf weight, main shoot length, leaf ground index, chlorophyll, nitrogen, zinc and iron content of grapevine cv ‘Italy’. Bio-fertilizers increased the nutrients such as nitrogen, zinc and iron concentrations and consequently increased the chlorophyll content of the leaves.  相似文献   
75.
Due to the paucity of data on separate spatial distribution of cosmogenic 7Be radionuclide activities in forest soil layers, a spatial study was performed in Mount Ida (Kazdagi)/Edremit, Turkey. In this study, it was aimed to examine the 7Be spatial variability and depth distribution in the surface soil layers. The 7Be activity concentrations were determined by HPGe gamma spectrometry system and the distributions of 7Be activities in the OL and OF + OH horizons throughout the region were mapped separately. Activity concentrations of 7Be in OL horizons and OF+OH horizons varied as 35 ± 23–701 ± 40 Bq kg?1 and 0.96 ± 0.63–197 ± 11 Bq kg?1, respectively. 7Be inventories (0.20 ± 0.06–5.69 ± 0.75 kBq m?2) in the study area were relatively higher when compared with the other regions of the world. 7Be inventories increased with altitude, slope and the thickness of the humus layer in some of the investigated area. Average 7Be activity level in deciduous forest stand type was significantly higher than that for coniferous and mixed stand types. Our limited data could not provide a latitudinal distribution pattern of 7Be soil inventory or precipitation dependence and further investigation is needed.  相似文献   
76.
1.?The objective was to evaluate the effects of brooding temperature on intestinal development, oxidative organ damage, and performance of chicks acclimated to high temperature during incubation. The effects of acclimation and brooding temperatures on slaughter weights of broilers under heat stress were also investigated.

2.?Eggs were incubated at either 37?8°C (INCCont) or heat-acclimated at 39?5°C for 6 h daily from d 10 to d 18 of incubation (INCH). Brooding temperatures at floor level were set at 32, 33?5 and 35°C (Bt32, Bt33?5, Bt35, respectively) for the first 5 d. The temperature was reduced gradually to 30°C from d 6 to d 10. From 21 to 42 d, broilers from INCCont Bt32 and INCH Bt32 and Bt35 were divided into two groups; half from each group was exposed to daily cyclic higher ambient temperatures, while the other half was reared at control temperature.

3.?INCH chicks had lower jejunum, but greater liver and residual yolk sac weights than INCCont chicks on the day of hatching. Although INCH chicks from Bt33?5 and Bt35 had lighter body weights than Bt32 on d 5, no significant differences were observed in the body weight of broilers among treatments at 10 and 21 d.

4.?Similar jejunum protein, alkaline phosphatase, maltase, glutathione, and malondialdehyde contents of chicks from INCCont and INCH suggested that heat acclimation during incubation has no effect on jejunum enzyme activity or oxidative status of chicks.

5.?Taking into account INCH Bt35 chicks having lower T3 levels on d 5, lower heterophil/lymphocyte (H/L) ratios and similar weights at 42 d under heat stress compared with control broilers, the results suggested that although higher brooding temperatures had no effect on body weights of INCH chicks during the brooding period, those broilers may able to cope better with heat stress.  相似文献   

77.
The influence of different copper and zinc contents in rations on blood serum concentrations was tested in a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute for Animal Health (FLI). A total of 60 German Holstein breed cows (38 first lactating and 22 second lactating cows) were tested. All animals received a diet based on maize‐ and grass silage ad libitum. The animals were divided into two groups with 30 cows each. Group A received concentrates supplemented with copper and zinc as recommended, whereas Group B was offered a concentrate with roughly double the amount of copper and zinc. Blood samples were taken several times during the lactation. The concentrations of copper and zinc in the serum were measured and correlations between trace element intake and their serum concentrations were calculated. The mean dry matter intake was significantly higher for cows in the second lactation (19.1 kg/day) than for cows in the first lactation (16.4 kg/day), whereas the DM‐intake was constant in the different feeding groups (17.3 and 17.4 kg/day). The correlation between feed intake in the first and the second lactation was r = 0.76. The copper concentration in the serum was not influenced by the different feedings (11.9 and 12.5 μmol/l), but high variations were found between the cows. The influence of the lactation number was not significant (12.1 and 12.4 μmol/l). In contrast to copper, the zinc concentration in the serum was significantly higher for Group B (14.0 μmol/l) than for Group A (12.2 μmol/l), respectively, for second lactating cows (13.8 μmol/l) in relation to 12.7 μmol/l for first lactating cows. The individual variation was also high as for copper. Neither the correlation between copper intake and copper serum concentration nor the correlation between zinc intake and zinc serum concentration was significant.  相似文献   
78.
79.
Summary

When strawberries (Fragaria ananassa Duch.) are produced in a greenhouse, usually two crops a year are obtained; in the fall and in the spring. To increase productivity, new cultivation techniques are needed. The aim of this study was to examine the effect of daylength treatments on the performance of strawberry plants to improve plant production protocols. The possibility of obtaining two successive crops during forcing was explored by exposing plants of cultivar Korona to two successive short day (SD) treatments followed by cold storage. The following daylength treatments were studied: 3 wk SD + 2 wk long day (LD) + 3 wk SD (3SD2LD3SD), 3 wk SD + 4 wk LD + 3 wk SD (3SD4LD3SD), and 10 wk SD (10SD). In addition, crown branching was studied in plants subjected to SD treatments. Two successive SD treatments enabled two successive flowering and cropping periods during greenhouse forcing after eight weeks of cold storage.The first SD treatment caused crown branching and induced flowering in the apical meristem of the main-crown and in the oldest axillary meristem(s), whereas younger axillary meristems were induced during the second SD treatment. Marketable yield and the number of inflorescences were comparable in 3SD4LD3SD and 10SD, but considerably lower in 3SD2LD3SD. However, this study demonstrated the high cropping potential of artificially SD treated plants, which makes them a potential alternative for greenhouse strawberry cultivation. Multi-crowned plants of ‘Korona’ can be produced by subjecting young plants to a three week SD treatment, and crown branches can be induced to flowering by a new SD treatment resulting in a very high cropping potential. Induced plants can be stored at –1°C for later forcing.  相似文献   
80.
Cultivated wheat, (Triticum aestivum L.), is one of the most important food crops in the world. The Aegilops L. genus is frequently utilized by plant breeders for improving the current wheat cultivars due to their close relationships. Therefore, understanding the phylogenetic relationships among the species of these genera is not only valuable for plant taxonomy, but also for plant breeding efforts. The presented phylogenetic analysis was based on the sequences of trnT-F chloroplast DNA containing three non-coding sub-regions. Twelve genotypes belonging to four species of Triticum L. genus and twenty-four genotypes belonging to eight species of Aegilops genus were used in the current study. The results postulated a close genetic relationship between diploid Aegilops species containing the BB genome and polyploid Triticum species. With the exception of Aegilops cylindrica Host (CCDD), all other Aegilops species having the CC genome were alienated from Aegilops speltoides Tausch (BB) and clustered together. These two clusters joined by a third cluster including the AA genome containing diploid Triticum species.  相似文献   
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