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81.
The Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is an important pest of small‐grain cereals, particularly wheat, worldwide. The most efficient strategy against the RWA is to identify sources of resistance and to introduce them into susceptible wheat genotypes. This study was conducted to determine the mode of inheritance of the RWA resistance found in ICARDA accession IG 100695, to identify wheat microsatellite markers closely linked to the gene and to map the chromosomal location of the gene. Simple sequence repeat (SSR) marker scores were identified in a mapping population of 190 F2 individuals and compared, while phenotypic screening for resistance was performed in F2 : 3 families derived from a cross between ‘Basribey’ (susceptible) and IG 100695 (resistant). Phenotypic segregation of leaf chlorosis and rolling displayed the effect of a single dominant gene, temporarily denoted Dn100695, in IG 100695. Dn100695 was mapped on the short arm of chromosome 7D with four linked SSR markers, Xgwm44, Xcfd14, Xcfd46 and Xbarc126. Dn100695 and linked SSR markers may be useful for improving resistance for RWA in wheat breeding.  相似文献   
82.
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.  相似文献   
83.
This short note reports the first record of the tomato leaf miner Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) in Kyrgyzstan. This pest was found in February 2017 in greenhouses producing tomatoes, located 15 km from Bishkek. Identification of the pest was carried out in the Plant Protection Department, Çukurova University, Turkey based on the morphology of adults and larvae and the male genitalia. According to initial surveys this pest could be a major threat to tomato production in Kyrgyzstan.  相似文献   
84.
85.
Changes in land use/land cover have important consequences on the management of natural resources including soil and water quality, global climatic systems and biodiversity. This study analysed the spatial and temporal pattern of land use/land cover change in the Camili forest planning unit that includes the Camili Biosphere Reserve Area within the Caucasian hotspot, in the northeast corner of Turkey. To assess the patterns during a 33‐year period, the necessary data were obtained from forest stand maps and evaluated with Geographic Information Systems and FRAGSTATS. Results showed that the total forested areas increased from 19 946·5 ha (78·6% of the study area) in 1972 to 20 797·3 ha (81·9 per cent) in 2005 with a slight net increase of 851 ha. Softwood cover types (411·8 ha) completely transitioned to other cover types over 33‐year period. In terms of spatial configuration, the total number of forest fragments increased from 172 to 608, and mean size of forest patch (MPS) decreased from 147·7 ha to 41·8 ha during the period. Nearly 84 per cent of the patches in 1972 and 93 per cent of them in 2005 generally seem to concentrate into 0–100 ha patch size class, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. There were apparent trends in the temporal structure of forest landscape, some of which may issue from mismanagement of the area, social conflict, and illegal utilization of forest resources due to ineffective forest protection measurements. The study revealed that it is important to understand both spatial and temporal changes of land use/land cover and their effects on landscape pattern to disclose the implications for land use planning and management. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
86.
Journal of Plant Diseases and Protection - In 2015 and 2017, potato storages were surveyed for the prevalence of atypical potato tuber rots in Nevşehir and Isparta Provinces of Turkey. About...  相似文献   
87.
Journal of Plant Diseases and Protection - Carnation, gerbera and lisianthus are an important part of the cut flower market worldwide, but plant-parasitic nematodes (PPN) affect their production...  相似文献   
88.
Maize (Zea mays L.) landraces are considered to be important genetic resources for improving maize. To use these sources effectively, the extent of genetic diversity among them needs to be determined. While maize landraces from different countries have been evaluated, there is only limited information available on Turkish maize landraces. Thus, our objective was to investigate the genetic relations among 35 different landraces, along with inbred lines B73 and Mo17, using the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We also measured seven kernel-quality traits, viz., protein content, oil content, zein content, lysine content, tryptophan content, and amylose/amylopectin content. Cluster analysis was performed to classify the Turkish maize landraces relative to protein-band variation. Results of protein-band analyses showed there was significant diversity among maize landraces. There was also considerable variation for the kernel-quality traits of the landraces. Kernel oil varied from 2.83% to 6.27%, protein from 6.67% to 11.34%, zein from 1.87% to 8.88%, tryptophan from 0.017% to 0.053%, lysine from 0.14% to 0.81%, amylose from 5.9% 37.6%, and amylopectin from 62.4% to 94.1% among the landraces. A total of 25 protein subunits, with molecular weight ranging from 10 to 110 kDa, were determined, and all of them, except for three bands, were polymorphic. Polymorphism information content (PIC) of the subunits ranged between 0.00 and 0.50. Maize landraces were classified into two main clusters; the first cluster included 18 landraces and inbred lines B73 and Mo17, whereas the second cluster comprised 17 maize landraces. Overall, results revealed that Turkish maize landraces having similar geographical origins were classified in the same clusters and exhibited a high level of diversity relative to protein subunits.  相似文献   
89.
This study aimed to investigate the effect of l -carnitine and energy level and on oxidant/antioxidant balance in laying hens subjected to high stocking density. A total of 176, 32-week-old laying hens were assigned to eight groups with four replicates and hens in four groups were placed at the normal stocking densities of 500 cm2/hen (four hens per cage) and in the remaining four groups were placed at the high stocking densities of 287.5 cm2/hen (seven hens per cage). Hens received diets of high (2,850 kcal/kg ME) or normal (2,650 kcal/kg ME) energy which are supplemented with 0 or 200 mg/kg l -carnitine for 70 days. Results showed that exposure to high stocking density increased (p < .05) plasma malondialdehyde (MDA) and nitric oxide (NO) levels and decreased (p < .05) erythrocyte superoxide dismutase (SOD), catalase (CAT) and superoxide dismutase (GPx) activities. l -carnitine supplementation increased (p < .05) erythrocyte SOD, CAT and GPx activities, and decreased (p <.05) MDA and NO level in high stocking densities. The oxidan/antioxidan balance of birds was not influenced by increasing dietary energy level. The results of the present study indicate that the supplementation of l -carnitine to the birds subjected to high stocking density could effectively reverse the negative effects of high stocking density by improving oxidant/antioxidant balance. Therefore, l -carnitine supplementation at level of 200 mg/kg to diet may be as a favourable alternative to deal with oxidative stress caused by high stocking density in laying hens.  相似文献   
90.
Inoculants are of great importance in sustainable and/or organic agriculture. In the present study, plant growth of barley (Hordeum vulgare) has been studied in sterile soil inoculated with four plant growth-promoting bacteria and mineral fertilizers at three different soil bulk densities and in three harvests of plants. Three bacterial species were isolated from the rhizosphere of barley and wheat. These bacteria fixed N2, dissolved P and significantly increased growth of barley seedlings. Available phosphate in soil was significantly increased by seed inoculation of Bacillus M-13 and Bacillus RC01. Total culturable bacteria, fungi and P-solubilizing bacteria count increased with time. Data suggest that seed inoculation of barley with Bacillus RC01, Bacillus RC02, Bacillus RC03 and Bacillus M-13 increased root weight by 16.7, 12.5, 8.9 and 12.5% as compared to the control (without bacteria inoculation and mineral fertilizers) and shoot weight by 34.7, 34.7, 28.6 and 32.7%, respectively. Bacterial inoculation gave increases of 20.3–25.7% over the control as compared with 18.9 and 35.1% total biomass weight increases by P and NP application. The concentration of N and P in soil was decreased by increasing soil compaction. In contrast to macronutrients, the concentration of Fe, Cu and Mn was lower in plants grown in the loosest soil. Soil compaction induced a limitation in root and shoot growth that was reflected by a decrease in the microbial population and activity. Our results show that bacterial population was stimulated by the decrease in soil bulk density. The results suggest that the N2-fixing and P-solubilizing bacterial strains tested have a potential on plant growth activity of barley.  相似文献   
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