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11.
With the availability of irrigation water, supplemental irrigation in winter-grown crops, such as lentil, wheat, and barley, has been intensely practiced to prevent crop yield losses due to the incidence of intermittent drought stress. In the crop growing seasons of 2006-2007 and 2008-2009, a study was conducted to determine the effect of supplemental irrigations on Canola (Brassica napus L. cv. Elvis F1) under the semiarid climatic conditions of the Harran plain, Sanliurfa, Turkey. A sprinkler irrigation system was used to irrigate the study plots. The irrigation treatments included 0.0, 0.25, 0.50, 0.75, and 1.0 (full irrigation) of Class-A pan evaporation amounts. The full irrigation treatment during both years consisted of 250 and 225 mm, respectively. In turn, crop water use values during the same years and treatments were 462 and 449 mm. In general, plant height and 1000 seed weight ranged from 140 to 165 cm and from 2.5 to 3.3 g, respectively, and these variables significantly differed among irrigation treatments (p < 0.05). Crop yield and above ground biomass measurements were affected by irrigation treatments and varied from 1094 to 3943 kg ha−1 and from 6746 to 18,311 kg ha−1, respectively (p < 0.05). Similarly, harvest index values were affected (p < 0.05) and ranged from 0.16 to 0.23 on average. The water use efficiency obtained in the different treatments indicated a strong positive relationship between crop yield and irrigation. Overall, our results indicate that supplemental irrigation substantially increased canola yield; however, for an optimum yield, full irrigation is suggested.  相似文献   
12.
Turkey’s globally important biodiversity in crisis   总被引:1,自引:0,他引:1  
Turkey (Türkiye) lies at the nexus of Europe, the Middle East, Central Asia and Africa. Turkey’s location, mountains, and its encirclement by three seas have resulted in high terrestrial, fresh water, and marine biodiversity. Most of Turkey’s land area is covered by one of three biodiversity hotspots (Caucasus, Irano-Anatolian, and Mediterranean). Of over 9000 known native vascular plant species, one third are endemic. Turkey faces a significant challenge with regard to biodiversity and associated conservation challenges due to limited research and lack of translation into other languages of existing material. Addressing this gap is increasingly relevant as Turkey’s biodiversity faces severe and growing threats, especially from government and business interests. Turkey ranks 140th out of 163 countries in biodiversity and habitat conservation. Millennia of human activities have dramatically changed the original land and sea ecosystems of Anatolia, one of the earliest loci of human civilization. Nevertheless, the greatest threats to biodiversity have occurred since 1950, particularly in the past decade. Although Turkey’s total forest area increased by 5.9% since 1973, endemic-rich Mediterranean maquis, grasslands, coastal areas, wetlands, and rivers are disappearing, while overgrazing and rampant erosion degrade steppes and rangelands. The current “developmentalist obsession”, particularly regarding water use, threatens to eliminate much of what remains, while forcing large-scale migration from rural areas to the cities. According to current plans, Turkey’s rivers and streams will be dammed with almost 4000 dams, diversions, and hydroelectric power plants for power, irrigation, and drinking water by 2023. Unchecked urbanization, dam construction, draining of wetlands, poaching, and excessive irrigation are the most widespread threats to biodiversity. This paper aims to survey what is known about Turkey’s biodiversity, to identify the areas where research is needed, and to identify and address the conservation challenges that Turkey faces today. Preserving Turkey’s remaining biodiversity will necessitate immediate action, international attention, greater support for Turkey’s developing conservation capacity, and the expansion of a nascent Turkish conservation ethic.  相似文献   
13.

Blechnum orientale L. is a traditional, medicinal fern found in China. To assess the characteristics of heavy metals and As accumulation, the fronds, roots, and the rooting soils of this fern were sampled from urban, suburban, and rural woodlands across Guangdong Province in southern China. The concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in both the fern and its rooting soils were separately detected by ICP-MS. Contamination levels of woodland rooting soils were also assessed using both a single pollution index and the Nemerow pollution index. Both the metal concentrations and the pollution index showed that soils from urban, suburban, and even rural woodlands were adversely contaminated by As, Cd, Hg, and Pb. Based on transfer factor, B. orientale had good translocation of As, Hg, and Mn, but poor translocation of Cd, Cr, Ni, Cu, Ni, Pb, and Zn from the roots to the fronds. This result suggests that this fern could be an excluder to latter metals. Despite the significantly higher levels of metals in the roots as compared with the fronds, the low bioaccumulation factor suggests that this fern has a weak capacity for metal accumulation.

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14.
Germplasm collections of C. reticulatum and C. echinospermum are limited, while both species face threats from over-grazing and habitat change in their natural environments. Recently many new accessions of C. reticulatum and C. echinospermum were collected in east and south-east Anatolia (Turkey) but they have not yet been evaluated for agro-morphological traits. Therefore, the current study investigated agro-morphological traits of new germplasm sources of C. reticulatum and C. echinospermum and evaluated resistance to biotic and abiotic stresses for chickpea improvement. The most attractive agro-morphological traits were canopy width, number of stems and pods per plant and biological yield. The most productive accessions of C. reticulatum and C. echinospermum had 712 and 625 pods per plant, respectively. Two distinct seed, flower and leaf shapes were found in accessions of C. echinospermum. Path analyses indicated that biological yield and harvest index had the most direct influence on seed yield in both species. Factor analyses showed that high seed yield in C. reticulatum depended on high biological yield and number of pods per plant, whereas high seed yield in C. echinospermum depended on harvest index. It was concluded that most accessions of C. reticulatum and C. echinospermum were not only resistant to some biotic and abiotic stresses but also had hidden alleles that could produce transgressive segregation in crosses to cultivated material.  相似文献   
15.
This experiment intended to assess the effect of sesame (SO), sunflower (SFO) and linseed (LO) oils on growth performance, fatty acid composition of fillet and liver or flesh quality traits of rainbow trout. Fish fed different four iso‐nitrogenous and iso‐lipidic experimental feeds. The control feed contained only fish oil as the primary lipid source. The fillet eicosapentaenoic acid and docosahexaenoic acid levels were the highest in fish fed control feed. In contrast, the liver eicosapentaenoic acid level was the highest in fish fed LO feed. Fish fed SFO feed had the highest level of total n?6 fatty acids in fillet and liver. Fish fed SO feed had the highest level of 18:1 n?9 fatty acid in fillet and liver. During the 12 days refrigerated storage period at 1°C, thiobarbituric acid (TBA) and pH values gradually increased in all dietary groups. However, trimethylamin nitrogen (TMA‐N) values increased in all dietary groups between days 0 and 9 during the storage period. Generally, pH value in fillets of control group was slightly higher than the other fish groups during 12 days refrigerated storage. Nevertheless, the chemical indicators of spoilage, TBA, TMA‐N and pH values were in the limit of acceptability for human consumption. Results of growth performance and chemical tests in the present study showed that sesame, linseed and sunflower oils could be used in feeds for rainbow trout. Moreover, we concluded that further researches should be carried out on the partial replacement of fish oil by sesame oil in rainbow trout nutrition.  相似文献   
16.
Calliteara pudibunda is a univoltine, polyphagous and native species producing periodic outbreaks which have been recorded only in Europe so far. Its larvae feed on the foliage of beech, oak and several other deciduous and coniferous trees. It is very widespread in Eurasia. In Europe, it is found between the 34th and 60th parallels. In Türkiye, it occurs mainly in coastal regions. Its outbreak range had been thought to be confined between the 48th and 57th parallels in Europe until the last two decades when outbreaks occurred in Italy and Türkiye. Therefore, the southern limit of its outbreak range can be updated as the 36th parallel. The outbreaks recur every 20–30 years, typically continue for 1–2 years, and end suddenly. Favourable meteorological conditions and a temporary rarity of parasitoids seem to be the main causes of the outbreaks. The damage on hosts is not evident until the third larval instar. The affected hosts may grow new shoots the next spring, as the larvae usually do not attack the terminal shoots. Increment loss is possible, but it may not be economically significant per se. However, tree mortality can occur with the combined effects of other stress factors. The impact of parasitoids and predators during the outbreaks is low. There are also fungal species identified from larvae and pupae, some of which might have significant potential in pest management. Additionally, Bacillus thuringiensis var. kurstaki (Btk), polyhedrosis viruses and light traps can potentially be used, although management practices are not recommended in C. pudibunda outbreaks.  相似文献   
17.
Meat quality characteristics of Turkish indigenous Hair goat kids reared under an extensive production system were investigated in this study. A total of 60 Hair goat kids (30 females and 30 males) were slaughtered at 3, 6, 9, and 12 months of ages. Slaughter age significantly affected meat quality characteristics. Cooking loss (P?<?0.01) and shear force value (P?<?0.001) increased with age. Meat color became darker red with increasing slaughter age (P?<?0.001). The percentage of fat of musculus (M.) semimembranosus increased with age (P?<?0.01). The percentage of saturated fatty acids was significantly higher (P?<?0.01), whereas the percentage of unsaturated fatty acids was lower (P?<?0.001) in the M. longissimus dorsi of the kids slaughtered at 3 months of age than those in the other age groups. The females had higher intramuscular fat than that in males (P?<?0.001) and meat from male kids contained a higher percentage of polyunsaturated fatty acid than that from females (P?<?0.01). In conclusion, meat from Hair kids slaughtered between 3 and 9 months of ages had better quality than those slaughtered at the other ages and also meat from male kids had better quality than those female kids slaughtered at the same age under extensive production system.  相似文献   
18.
A global positioning system (GPS) receiver is an important sensor used in modern farming, particularly in precision agriculture to determine geographic location and ground speed. The aim of this study was to investigate the effectiveness of two low-cost GPS receivers for measuring ground speed under varying speed conditions on four different dates. A rotary shaft encoder on an auxiliary wheel mounted on an agricultural tractor was used as a reference. A significant time lag between the rotary encoder speed and the GPS speed was found over a range of speeds. It was observed that the GPS speed lagged the encoder speed in both increasing and decreasing speeds. The average time lag was found to be between 3.6 and 5.2 s for Receiver 1 while Receiver 2 had a time lag from 1.7 to 2.5 s. A significant difference was found between the two receivers for increasing and decreasing speeds in terms of time lags (P < 0.05). A post correction by shifting the GPS speed increased the accuracy of the speed measurement capability of both receivers resulting in an average correlation coefficient of 0.30–0.90 for Receiver 1 and 0.65–0.98 for Receiver 2. Effect of USB-to-COM converter was also studied and it did not have a significant effect on time delay. The GPS receivers provided reliable data during constant speed operating conditions; however, caution should be exercised in varying speed conditions when using low-cost GPS receivers. Also, the companies that produce GPS-based speed sensors should supply technical specifications related to velocity estimates during acceleration and deceleration.  相似文献   
19.
Ascochyta blight, caused by Didymella rabiei, affects both domesticated chickpea and its congeneric wild relatives. The aim of this study was to compare the aggressiveness of D. rabiei isolates from wild and domesticated Cicer spp. in Turkey and Israel on wild and domesticated hosts from both countries. A total of eight isolates of D. rabiei sampled from C. pinnatifidum, C. judaicum and C. arietinum in Turkey and Israel was tested on two domesticated chickpea cultivars and two wild Cicer accessions from Turkey and Israel. Using cross-inoculation experiments, we compared pathogen aggressiveness across the different pathogen and host origin combinations. Two measures of aggressiveness were used, incubation period and relative area under the disease progress curve. The eight tested isolates infected all of the host plants, but were more aggressive on their original hosts with one exception; Turkish domesticated isolates were less aggressive on their domesticated host in comparison to the aggressiveness of Israeli domesticated isolates on Turkish domesticated chickpea. C. judaicum plants were highly resistant against all of the isolates from different origins except for their own isolates. Regardless of the country of origin, the wild isolates were highly aggressive on domesticated chickpea while the domesticated isolates were less aggressive on the wild hosts compared with the wild isolates. These results suggest that the aggressiveness pattern of D. rabiei on different hosts could have been shaped by adaptation to the distinct ecological niches of wild vs. domesticated chickpea.  相似文献   
20.
Bovine spongiform encephalopathy (BSE), a member of the transmissible spongiform encepahlopathies, has been a notifiable disease in Turkey since 1997. In 2002, the BSE status of Turkey was assessed by the EU Scientific Steering Committee as "it is likely but not confirmed".This study presents the results of a targeted surveillance study to assess the presence of BSE in the age risk population of Bursa, Turkey. In the assessment procedure, the immunohistochemical detection of protease-resistant prion protein (PrP-Sc) was aimed at and applied to 420 brain tissues of cattle slaughtered in Bursa at an age of 30-months and older. None of the samples were positive for BSE.  相似文献   
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