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91.
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
92.
Improved fallows involving short-rotation woody and/or other perennial species are increasingly being tried as a means of sustaining crop production in impoverished farming systems of sub-Saharan Africa. The soil-improving potential of two tree species [Gliricidia sepium (gliricidia) and Pteocarpus erinaceus (pterocarpus)] and a shrubby legume Stylosanthes hamata (stylosanthes) was investigated in a four-year study on farmer's field and in a research station in the Koutiala region in southern Mali (12.25° N, 5.42° W; 650 to 850 mm annual, unimodal rainfall; on a Typic Plinthustalf). Two strategies for soil improvement were tested: improved fallow sensu stricto and biomass transfer, the former on-farm and the latter on-station. In the on-farm experiment, maize (Zea mays) yielded best when it followed a two-year fallow of gliricidia alone or in association with stylosanthes. On the research station, maize dry matter production and grain yields during two seasons following the application of ex-situ grown biomass were similar and highest in the stylosanthes- and manure-applied treatments. The biomass decomposition rates of the three species were in the order: gliricidia > stylosanthes > pterocarpus. The treatments did not have any significant effects on the soil fertility parameters that were monitored, possibly because of the short-term nature of the study. The treatments effects on crop yields were, however, significant. Gliricidia + stylosanthes in combination appeared to be particularly promising as short-rotation-fallow species in the region.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
93.
BACKGROUND: The aim of this study was to investigate the prevalence of hepatitis B virus (HBV) genotypes in Isparta, Southwest of Turkey, as well as the clinical features and transmission route for patients with HBV infections. METHODS: Patients (n = 135) with HBV infection were included in the study. Epidemiological and clinical data were obtained. HBV genotypes were determined with a preS2 epitope ELISA kit. RESULTS: Although the HBV transmission route remained unidentified in 51.1% of the patients, blood contact was determined as the most common probable transmission route (38.5%). One hundred twenty-four (91.8%) of 135 samples, could be genotyped. One hundred fifteen (85.1%) were genotyped as type D/E, six (4.4%) were genotyped as type A, two (1.4%) were genotyped as type C, and one (0.7%) were genotyped as type F. CONCLUSION: Genotype D/E is determined as the predominant HBV genotype circulating in Isparta, Southwest of Turkey. No relationship between genotypes and disease severity and transmission route has been detected. 相似文献
94.
BACKGROUND: Bifora radians, an annual weed in winter wheat, is distributed mainly in the Mediterranean area, Asia Minor and the Caucasus. It infests winter-sown crops of the Central Anatolia and Middle Black Sea regions of Turkey. Field experiments in heavily B. radians-infested fields were conducted over 3 years in Samsun, Turkey, to determine the response of B. radians to ALS-inhibiting herbicides, because growers had complained of a decrease in herbicide effect. RESULTS: The efficacy of ALS inhibitors on a putatively tolerant population sprayed annually with ALS inhibitors and an adjacent allegedly sensitive population was estimated at the ED50 and ED90 response levels. The recommended rates of herbicides controlled 90% of the weed (ED90) in the sensitive population at the early stage of B. radians development, but not in the tolerant population. The relative potencies (EDx(tolerant)/EDx(sensitive)) of herbicides on the two populations were estimated by assuming years as being random effects. The relative potency was on average about 1.7, irrespective of the EDx levels. CONCLUSION: Although the relative potencies were not large, they were large enough to be noted by growers. In field experiments it would be important to establish tools demonstrating when farmers recognise loss of herbicide efficacy. There has been no indication of evolution of resistant biotypes so far, but continuous spraying favours biotypes with increased levels of tolerance. Copyright © 2011 Society of Chemical Industry 相似文献
95.
96.
Effect of breed on fattening performance, slaughter and meat quality characteristics of Awassi and Morkaraman lambs 总被引:1,自引:0,他引:1
Nurinisa Esenbuga Muhlis Macit Mevlut Karaoglu Vecihi Aksakal Muhammet Irfan Aksu Mehmet Akif Yoruk Mehmet Gul 《Livestock Science》2009,123(2-3):255-260
The influence of breed on fattening performance, slaughter and meat quality traits was studied in Awassi and Morkaraman male lambs at approximately 8 months of age. All of the groups were fed a diet consisting of concentrate mixture offered ad libitum, and 300 g of grass hay per lamb per day during 60-day fattening period. Initial live weight, final live weight, daily weight gain and feed conversion efficiency (concentrate and hay consumption for 1 kg of live weight gain) were 39.63 kg, 55.08 kg, 0.258 kg and 6.37 for Awassi; 40.54 kg, 55.58 kg, 0.234 kg and 6.77 for Morkaraman, respectively. The effect of breed on fattening performance and slaughter traits except for LD area was not significant. In addition, meat colour parameters (L = lightness, a = redness, b = yellowness, H = hue angle and C = chroma), pH values, drip loss and sensory attributes were not affected by breed in present study. A significant muscle effect was observed for instrumental measurements of some meat quality characteristics as meat colour parameters (L, a and C), collagen, drip loss, pH, moisture and protein content, WBS, and for some sensory attributes (tenderness, juiciness, acceptability and number of chewing). Results of this study indicate that fattening performance, slaughter and meat quality traits were similar between Awassi and Morkaraman male lambs. 相似文献
97.
We studied the effect of different food sources, infective juveniles of the entomopathogenic nematodes, Steinernema feltiae and Heterorhabditis bacteriophora (Rhabditida: Steinernematidae, Heterorhabditidae), and tissues from the insect larva, Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), on the development, reproduction and longevity of Sancassania polyphyllae (Acari: Acaridae). We showed that the immature mite stages - protonymph and tritonymph - could develop to the next developmental stage on living or sonicated (i.e., ruptured) S. feltiae or H. bacteriophora. However, the mite larval stage could only develop to the next developmental stage on sonicated infective juveniles of the nematodes. Subsequently, we demonstrated that S. polyphyllae completed development from protonymph to adult on live S. feltiae or H. bacteriophora, whereas all immature stages of S. polyphyllae completed their development from larva to adult on insect tissues. The total developmental period of S. polyphyllae that fed on insect tissues was significantly shorter than those that fed on live infective juveniles. The pre-oviposition, oviposition, and post-oviposition periods and female longevity were not significantly different among the food sources. The total and daily fecundity of S. polyphyllae feeding on P. fullo and G. mellonella was significantly higher than those feeding on S. feltiae and H. bacteriophora, although there was no significant difference observed between P. fullo and G. mellonella or between S. feltiae and H. bacteriophora. The net reproductive rate (R0) was highest (588.3♀/♀) when S. polyphyllae fed on P. fullo. The longest mean generation time (T0) occurred on H. bacteriophora (12.6 days) and the shortest occurred on P. fullo (10.5 days). S. polyphyllae, which fed on P. fullo (rm=0.61) and G. mellonella (rm=0.55) had the highest intrinsic rate of increase (rm) compared to mites that fed on S .feltiae (rm=0.45) and H. bacteriophora (rm=0.41). 相似文献
98.
The effects of Tomato spotted wilt virus (TSWV) on yield and quality of tomato fruits were studied from May through November of 2004 at the Experimental Field of
the Agricultural Faculty of Ondokuz Mayis University, in Samsun province, Turkey. TSWV caused 42.1% and 95.5% reduction in
yield and marketable value of tomato, respectively. TSWV infection in tomato crop caused significant (P < 0.05) reductions in weight, total number, width and length of the fruits in infected plants. Reductions in yield-contributing
parameters were 26.61% in weight, 20.18% in number, 10.94% in width and 11.93% in length of fruits. It is difficult to estimate
the actual yield loss and influence levels of TSWV in the field. Economic data are scarce, but in the present study it was
estimated that the yield loss due to TSWV in tomatoes was approximately $0.9 million in Samsun, Turkey. 相似文献
99.
Along with sulfate turpentine, the essential oils obtained by steam distillation from nine plant species naturally grown in Turkish forests were tested at three different concentrations to evaluate their effectiveness against the larvae of pine processionary moth (Thaumetopoea pityocampa Schiff). The results indicated that the essential oils from the nine species and sulfate turpentine were effective against the larvae of T pityocampa. The most effective essential oil in the control of the larvae was steam-distilled wood turpentine, followed by thyme herb oil, juniper berry oil, laurel leaf oil, lavender flower oil, eucalyptus leaf oil, lavender leaf oil, cypress berry oil, essential oil of styrax and sulfate turpentine, respectively, in terms of mean mortality time. It is therefore feasible to use these essential oils as environment-friendly insecticides in the control of T pityocampa. 相似文献
100.
This study was conducted to determine the pathological changes in testes and epididymides and plasma testosterone levels of adult roosters during experimentally induced aflatoxicosis. In the study, 24 months of age, 32 Babcock breeder males were used, and they were divided into four groups each containing 8 animals. The groups were designed as follows; group 1: Control, no aflatoxin (AF), group 2: 5 ppm (parts per million) total aflatoxin (AF; B1, B2, G1, G2), group 3: 10 ppm AF and group 4: 20 ppm AF in the diet, and the birds were fed for 8 weeks. Grossly, it was seen that the testes of all AF-treatment groups birds were significantly (P < 0.001) atrophied when compared with those of control birds. Histopathologically, there was no spermatogenesis in the testes of 4, 5 and 6 cocks fed on a diet containing AF 5, 10 and 20 ppm, respectively. Furthermore, abnormal spermatozoa were observed in some of AF-treatment groups (in 2 cases in each of 5 and 10 ppm AF-treated groups, and in one case in 20 ppm AF-treated group). There were also mononuclear cell infiltration and/or focal lymphoid cell accumulation in the intertubular areas of the testes and epididymides in all AF-treatment groups. In conclusion, it has been shown that AF might totally or partially (dose related) suppress spermatogenesis, cause abnormality in spermatozoa and atrophy in testes. Furthermore, there was degeneration and desquamation in the epithelium and decrease in the size and thickness of the germinative layer of the seminiferous tubules, and lowered plasma testosterone levels in adult roosters. 相似文献