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71.
Apigenin di-C-glycosides (ACGs) are present in the grain of bread wheat and other related cereals primarily as one or two sets of Wesseley-Moser isomers containing either arabinose and glucose (ACG1) or arabinose and galactose (ACG2) on the A ring of apigenin. These compounds may contribute to the yellow colour of wheat-based products made under alkaline conditions and in addition, have possible roles in a number of plant physiology processes and human health. The aims of this investigation were to survey genetic variation for ACG content and composition in hexaploid bread wheat (Triticum aestivum L.) and to examine ACGs in the putative progenitors of hexaploid wheat and available genetic stocks as a first step towards understanding the mechanisms involved in their biosynthesis and genetic control. Substantial variation in both grain ACG content and the ratio, ACG1/ACG2, were identified within bread wheat cultivars and related species. Genotype controlled the major portion of the variation. ACG content appeared to be a multigenic trait whereas variation in ACG1/ACG2 was associated with a limited number of chromosomes, in particular chromosomes 1B, 7B and 7D. The results suggest that it should be possible to manipulate both ACG content and composition traits through breeding.  相似文献   
72.
In spite of the fact that egg yolk from different avian species has successfully been used as an additive for the cryopreservation of sperm in mammalian species, its efficacy for cryopreserving fish sperm has not previously been tested comparatively. Therefore, the present study was carried out to determine the effect of egg yolks from different avian species, namely domestic chicken (Gallus gallus domesticus), turkey (Meleagris gallopavo) and quail (Coturnix coturnix), on post-thaw motility and fertilization ability of cryopreserved common carp spermatozoa. Egg yolks from chicken, turkey and quail were analysed for moisture, total fat, protein, cholesterol and phospholipid profile. Total fat and cholesterol contents of the turkey egg yolk were higher than chicken and quail egg yolks (p < 0.05). Semen was frozen according to conventional slow freezing procedure. The extender contained 350 mM glucose, 30 mM Tris and 5 % glycerol supplemented with different ratios of avian egg yolk (10, 15 and 20 %). Semen was equilibrated at 4 °C for 15 min and placed into 0.25-ml straws and frozen in liquid nitrogen vapour (for 10 min at ?120 °C) and finally stored in liquid nitrogen (?196 °C) tank. The frozen spermatozoa were thawed in a water bath at 35 °C for 30 s. Fertilization was conducted using a ratio of 1 × 105 spermatozoa/egg. Cryopreservation experiments resulted in higher post-thaw motility and fertilization rates. Mean post-thaw motility of cryopreserved spermatozoa was between 45 and 80 %, and fertilization rates, expressed as the percentage of eyed embryos, ranged from 70 to 95 %. In conclusion, the present study showed that turkey and quail egg yolks are suitable alternatives to the chicken egg yolk for the cryopreservation of common carp spermatozoa.  相似文献   
73.
Plant biowaste of alien species represents a potential resource for compost production. This study investigated the seed and seedling responses of maize and pea to composts generated from the biowaste of four invasive species in eThekwini, South Africa: Acacia podalyriifolia, Hedychium gardnerianum, Litsea glutinosa, and Tithonia diversifolia. Except for a 40% concentration of T. diversifolia, leachates of the biowaste from the four species had no marked effects on germination. In seedling growth studies, Berea Red soil (control) was supplemented with composts produced using combinations of the four species (A. podalyriifolia + T. diversifolia [T1], A. podalyriifolia + H. gardnerianum [T2], L. glutinosa + T. diversifolia [T3], and L. glutinosa + H. gardnerianum [T4]), and a commercial compost (T5). Carbon and nitrogen levels of the biowaste composts were higher than the control, while their associated C/N ratios were low enough to encourage microbial growth, facilitate rapid decomposition, and support plant growth. A comparison of percentage seedling production, growth rate, and biomass production between the commercial compost and alien biowaste treatments revealed all parameters to be statistically comparable among T5, T1, and T3 for maize, and between T5 and T1 for pea. These superior biowaste composts did not enhance growth relative to the commercial compost, but supported growth to the same extent. However, N and P levels in T1 and T3 were lower than the commercial compost and appear to have altered biomass allocation patterns in both species relative to the commercial compost. The results suggest that there is potential to use invasive alien plant biowaste to improve soil for agricultural purposes.  相似文献   
74.
The study was conducted to investigate the effects of feeding different levels of dried cassava leaves at 0%, 20%, 40% and 60%, respectively, using guinea grass as basal feed, on the haematological and serum biochemical parameters of West African Dwarf (WAD) goats. The study lasted for 116 days during which haematological and serum biochemical parameters were monitored in 40 male goats before and after, using a completely randomized design. At the start of the experiment, packed cell volume (PCV) ranged from 21.5% to 25.5% while haemoglobin concentration (Hb) and RBC significantly (P < 0.01) ranged from 7.3 to 8.6 g/dl and 10.4 to 13.2 × 1012/l, respectively. White blood cells reduced significantly (P < 0.05)) from 16.4 to 11.7 × 109/l) as dried cassava leaves increased in the diets. At the end of the trial, there was a slight increase in the values of PCV and Hb in the diets (P > 0.05). Lymphocyte reduced significantly (P < 0.05) from 50.0% to 63.5% in the diets. Neutrophils, however, increased (P > 0.05) at the 0% to 40% levels and reduced at the 60% level of dried cassava leaves inclusion. At the start of the experiment, values for glucose significantly (P < 0.05) ranged from 40.1 to 56.0 mg/dl. Total protein and albumin values ranged significantly (P < 0.05) from 56.0 to 68.5 g/dl and 30.6 to 38.4 g/dl, respectively. At the end of the experiment, serum creatinine increased significantly (P < 0.05) as the level of dried cassava leaves increased from 0% to 60% in the diets. The study revealed that inclusion of dried cassava leaves in the diets of West African Dwarf goats had no deleterious effects on the haematological and serum biochemical parameters of WAD goats and could therefore be included in ruminant diets up to 60%.  相似文献   
75.
Daily milk yield of Ogaden cattle was estimated from milk suckled by 269 calves born and maintained between 1994 and 2004 at Haramaya University Beef Farm, Ethiopia. The weigh–suckle–weigh method and the growth of calves were used to estimate the yield. Mean predicted daily milk yield of the breed based on the weigh–suckle–weigh method was 4.39 ± 0.03 kg day−1. Daily milk yield estimated from the growth of calves up to 3 months of age was 4.59 ± 1.43 kg day−1. The milk yield was significantly affected by seasons of calving (p < 0.001), parities of the dams (p < 0.05), weeks of lactation (p < 0.001) and birth weights of calves (p < 0.05). A relatively higher milk yield was observed from cows calved during the long rain season. A higher milk yield was produced by cows in fifth parity. Heavier calves at birth suckled more milk than lighter calves. Daily milk yield was significantly higher in 3–6 weeks of lactation. The result of this study indicated that the milk yield produced by Ogaden breed was relatively higher than the yield of some Zebu breed measured by partial suckling system in Ethiopia and was comparable to the yield from Zebu cattle in the tropics estimated by the same method.  相似文献   
76.
Geostatistical approaches (ordinary kriging (OK) and indicator kriging (IK)) were used in this study to investigate the spatial and temporal variations in groundwater nitrate concentrations in Çar?amba plain of Turkey. Groundwater samples were taken in April 2012, July 2012, September 2012 and March 2013 from 78 groundwater wells. The experimental semivariograms were often fitted well by a Gauss model for April 2012 and September 2012, whereas a spherical model was fitted to experimental semivariograms for July 2012 and March 2013. Spatial distribution maps revealed that groundwater nitrate concentrations were above the threshold value of 50 mg L?1 specified for drinking water in 4.3% of the study area in April 2012, 40.8% in July 2012, 32.8% in September 2012 and 19.1% in March 2013. Probability maps created with IK showed that 3.1% and 3.2% of the total area had very strong probability (0.8–1.0) of exceeding the threshold nitrate concentration in July 2012 and September 2012, respectively. Current findings revealed that groundwater nitrate concentrations changed seasonally and increased much more in summer. It was concluded that OK and IK may yield significant outcomes for groundwater management, identification of risky sites for potential pollution and identification of the sites with excessive fertilizer uses.  相似文献   
77.
We examined the role of jasmonic acid (JA) in faba bean under cadmium (Cd) stress, which reduces the growth, biomass yield, leaf relative water content (LRWC) and pigment systems. Hydrogen peroxide (H2O2) and lipid peroxidation (malondialdehyde [MDA]) levels increased by 2.78 and 2.24-fold, respectively, in plants under Cd stress, resulting in enhanced electrolyte leakage. Following foliar application to Cd-treated plants, JA restored growth, biomass yield, LRWC and pigment systems to appreciable levels and reduced levels of H2O2, MDA and electrolyte leakage. Proline and glycine betaine concentrations increased by 5.73 and 2.61-fold, respectively, in faba bean under Cd stress, with even higher concentrations observed following JA application to Cd-stressed plants. Superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase levels rose by 87.47%, 130.54%, 132.55% and 37.79%, respectively, with Cd toxicity, with further enhancement of antioxidant activities observed following foliar application of JA. Accumulation of Cd in roots, shoots and leaves was also minimized by external supplementation of JA. In conclusion, JA mitigates the negative impacts of Cd stress in faba bean plants by inhibiting the accumulation of Cd, H2O2 and MDA, and by enhancing osmolyte and antioxidant activities that reduce oxidative stress.  相似文献   
78.
This report examines the effectiveness of clindamycin for the treatment of babesiosis in dogs (n=10) experimentally infected with Babesia gibsoni (B. gibsoni). Clindamycin (25 mg/kg body weight, per os, q 12 hours for 14 days) gradually reduced parasitemia levels and induced morphological changes that indicated degeneration of parasites (e.g., segmentation; size reduction; localization in the cell limbic and/or torn state of the nucleus; and swelling, decrease, or disappearance of the cytoplasm) in the majority of dogs. Clindamycin treatment reduced the clinical symptoms characteristic of Babesia infection, including anemia, anorexia, and listlessness. Clindamycin might be useful as a medicine for treatment of B. gibsoni infection.  相似文献   
79.
The study deals with the tachinid parasitoids ofAncyrosoma leucogrammes (Gmelin) (Heteroptera: Pentatomidae):Clytiomya dupuisi Kugler,Clytiomya sola (Rondani) andGymnosoma clavatum (Rohdendorf) (Diptera: Tachinidae). All species are recorded for the first time as parasitoids ofA. leucogrammes, andC. dupuisi was reared for the first time from a host. The parasitization rates ofC. dupuisi on adults ofA. leucogrammes varied from 7% to 9% between 1994 and 1999.C. sola andG. clavatum were reared in only small numbers. http://www.phytoparasitica.org posting July 10, 2003.  相似文献   
80.
The object of this study was to determine the cause of differences in the improvement in liquid penetration of precompressed wood species. The maximum amount of water uptake by the capillary rise method and changes in the aspirated pits seen with scanning electron microscopy before and after of preextraction and precompression were investigated using heartwood samples of four softwoods. The height of penetration and the weight by the capillary rise method for preextractive wood powders are discussed. Three wood species andLarix leptolepis showed marked increases in the amount of solution uptake after precompressed treatment only.Larix leptolepis wood required compression after extraction by boiling in water. These differences among wood species were caused by the accumulation of extractive material. It was also recognized that the accumulative material inLarix wood has plasticity and that inPseudotsuga is brittle. Based on these results it was found that it is difficult to destroy aspirated pits in the former and easy in the latter. On the other hand, the difference in penetration of each wood species was caused by the quantity and quality of the extraction material in addition to the extent of the wettability of the surface of the cell cavity as well as aspirated pit.Part of this report was presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996  相似文献   
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