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21.
Erdogan  Cem  Ozdem  Ayse  Alpkent  Yasin Nazim  Demiroz  Duygu 《Phytoparasitica》2023,51(2):323-335
Phytoparasitica - The Green apple aphid, Aphis pomi de Geer (Hemiptera: Aphididae), is one of the most common and serious insect pests of apple orchards in Turkey. This species feeds on succulent...  相似文献   
22.
The aim of this study was to determine the salt tolerance of pepper (Capsicum annuum L.) under greenhouse conditions and to examine the interactive effects of salinity and nitrogen (N) fertilizer levels on yield. The present study shows the effects of optimal and suboptimal N fertilizer levels (270 kg ha?1 and 135 kg ha?1) in combination with five different irrigation waters of varying electrical conductivity (EC) (ECiw = 0.25, 1.0, 1.5, 2.0, 4.0, and 6.0 dS m?1) and three replicates per treatment. At optimal N level, yield decreased when the irrigation water salinity was above ECiw 2 dS m?1. At the suboptimal N level, a significant decrease in yield occurred only above ECiw 4 dS m?1. At high salinity levels the salinity stress was dominant with respect to yield and response was similar for both N levels. Based on the results it can also be concluded that under saline conditions (higher than threshold salinity for a given crop) there is a lesser need for N fertilization relative to the optimal levels established in the absence of other significant stresses.  相似文献   
23.
This, partly retrospective study, was designed to determine the seroprevalence of Schmallenberg virus (SBV), a new Orthobunyavirus first reported in Germany in late 2011, in domestic ruminants from the Middle Black Sea, West, and Southeast regions of Turkey. An indirect enzyme-linked immunosorbent assay was used to screen serum samples collected from slaughterhouse animals between 2006 and 2013. The overall seroprevalence was 335/1,362 (24.5 %) with 325/816 (39.8 %), 5/307 (1.6 %), 3/109 (2.8 %), and 2/130 (1.5 %) recorded in cattle, sheep, goats, and Anatolian water buffalo, respectively. This is the first study to demonstrate the presence of antibodies to SBV in Turkish ruminants; it indicates that cattle are more susceptible to infection than sheep, goats, or buffalo and that exposure of domestic ruminants to SBV in Turkey may have occurred up to 5 years prior to the first recorded outbreak of the disease in 2011.  相似文献   
24.
Thermal treatment is used to preserve the wood without any addition of any toxic chemicals. This process increases the dimensional stability and darkens the color of the wood. The improvement of the resistance to decay of wood by thermal treatment is also often suggested in the literature. However, some latest works contested if the durability of heat-treated wood is improved when it is used in contact with ground. The objective of this study was to investigate the possibility of thermally treating electrical poles which are larger compared to the standard wood lumber. One of the applications for thermally treated wood poles could be their use in environmental sensitive areas (along rivers, for example) as a replacement for untreated western red cedar (WRC) poles which are more expensive. Green and pre-dried red pine (Pinus resinosa) and jack pine (Pinus banksiana) poles, both with circular and square cross-sections, were heated to high temperatures under humid and inert atmosphere. Operating parameters such as maximum treatment temperature, maintenance time at this temperature, heating rate and gas humidity were varied in order to find most suitable treatment conditions for the poles. The tests showed that most of the cracks are formed during the drying process while thermal treatment only widened already existing cracks. The circular shape seems to promote crack formation during the drying period since the directional dependence of shrinking creates more stresses in circular poles compared to the square poles. A slight decrease in flexibility of the wood with increasing temperatures was observed. The protecting effect of gas humidity against oxidation of wood and the importance of the application of a moderate heating rate for poles with large cross-sections are also demonstrated in this article. The impact of the heat treatment on the resistance to decay of electrical wood pole will be presented in a future publication.  相似文献   
25.
Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status.  相似文献   
26.
A feeding experiment was conducted to study the response of rainbow trout juveniles fed different levels of lupin meal in diets for rainbow trout juveniles. Very limited information is available on the relationship between dietary lupin meal in rainbow trout health status. Therefore, this study aimed to determine the effects of lupin meal inclusion levels (0%, 15%, 30%, 45%, and 60%) on growth performance and health status of rainbow trout juveniles. The experimental diets (LM0, LM15, LM30, LM45, and LM60) were formulated iso‐nitrogenous (41% crude protein) and iso‐calorific (18% crude lipid). The fish were fed twice a day. As a result, the best growth performance was observed in fish fed with LM15 and LM30 diets. No significant differences were detected among experimental groups in terms of body compositions. The haematological values showed significantly (p < 0.05) lower heamatocrit and mean cellular volume (MCV) in the group of LM60 compared with the other groups. For the other haematological parameters such as haemoglobin, red blood cell and mean cellular haemoglobin studied in the present study no significant differences were observed (p < 0.05). The lupin meal included groups showed significant reduction in total protein (TPROT), triglyceride (TROG), cholesterol (CHOL), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) compared with the control group (p < 0.05). The inclusion of lupin meal did not cause any changes in glucose (GLU), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) between the treatment groups (p < 0.05). In conclusion, lupin meal might be used in rainbow trout diets up to 30% without any malnutrition effect on growth performance, haemotological and serum biochemical parameters.  相似文献   
27.
We examined the effect of thermal treatment at two temperatures (60 s of 90°C dry heat and 60 min in 40°C hot water) versus control conditions on the germination of oriental spruce (Picea orientalis (L.) Link.) seeds originating from different subalpine provenances. Cutting test results showed that there was wide variation (between 10% and 90%) in filled seed rates. The results revealed that highest germination yield was attained via the hot water treatment. The maximum germination percentages were observed in seeds from “tree 3” in the first tree collective of provenances 1 (85.33 ± 5.77 control; 88.67 ± 7.02 via the hot water treatment; 82.00 ± 10.58 via the dry heat treatment) and 3 (70.67 ± 17.24 control; 88.00 ± 4.00 via the hot water treatment; 86.67 ± 11.37 via the dry heat treatment). The mean germination percentages were significantly different (p-value < .05): percentage values were 32.57% in provenance 1, 23.22% in provenance 3, 12.25% in provenance 4, and 2.82% in provenance 2. Mean germination time of seeds from different provenances and experiencing various pretreatments showed significant variation. The best pretreatment increase in germination rates was achieved via the wet heat method (60 min in 40°C hot water).  相似文献   
28.
Chemical composition of grape canes   总被引:1,自引:0,他引:1  
In this study, chemical composition of canes which were sampled from ten different grape cultivars was investigated. For the determination of total phenolics, total flavanols and total flavonol contents, canes were analyzed spectrophotometrically. The phenolic compositions of the canes, including caffeic acid, catechin, p-coumaric acid, epicatechin, gallic acid, luteolin and trans-resveratrol were detected by HPLC. The anthron method was used for the determination of total carbohydrate content. The minerals such as K, P, Ca, Fe, Mg and Zn were determined by ICP-OES. All the parameters investigated in this study significantly changed depending on the cultivar. The results showed that grape canes as agricultural wastes from commercial viticultural activities represent a potentially important source of phenolics, minerals, carbohydrates and proteins. Therefore the grape canes may be used as an easily accessible source of natural antioxidants and food supplement.  相似文献   
29.
  • ? The resorption of nutrients (mainly N and P) from senescing leaves may be a key component of adaptive mechanisms that conserve scarce nutrients. Resorption may be expressed in two ways as resorption efficiency (RE) which is the ratio of the resorbed amounts of nutrient losses during leaf senescence in relation to its prior amount deposited in leaves and resorption proficiency (RP) is the level to which nutrient concentration per unit leaf mass is reduced in senescent leaves.
  • ? There is still much debate whether or not different life-forms (i.e. deciduous and evergreen species) show different foliar resorption patterns. Two sympatric species, namely Quercus petraea (Mattuschka) Liebl. subsp. iberica (Steven ex Bieb.) Krassiln. (deciduous) and Arbutus andrachne L. (evergreen) along an elevational gradient were compared with each other to determine whether or not nitrogen and phosphorus resorption efficiency and proficiency varies along the elevational gradient and which leaf parameters were as related to RE and RP.
  • ? NRE was found to be rather low in Q. petraea subsp. iberica compared to other deciduous species. Similarly, PRE in A. andrachne was rather low compared to other evergreen species. Mean residence time (MRT) measures how long a unit of nitrogen (MRTN) and phosphorus (MRTP) is present in the plant. MRTN and MRTP were found to be considerably higher in A. andrachne compared to Q. petraea subsp. iberica. In both species, the foliar N/P ratio was below 14 along the elevational gradient and, according to this threshold value, N-limitation occurred in the study area. Although both species in the present study show incomplete resorption deciduous species was more proficient as compared to evergreen one due to low N and P concentrations in senescent leaves. Based on the significant correlations (p < 0.05 and 0.01) between MRT and foliar resorption, it can be concluded that MRT could interfere with the mechanisms controlling nutrient resorption.
  •   相似文献   
    30.
    The pollen germination and pollen tube growth among nine Pistacia genotypes was quantified in order to identify differences in the tolerance of pollen to temperature variations. The effect of temperature on in vitro pollen germination and pollen tube growth was investigated in Pistacia vera (Uygur, Atli, Kaska, Sengel, Kavak), P. atlantica, P. khinjuk, P. terebinthus and P. palaestina. When pollen was incubated in a germination medium for 24 h in darkness, distinct differences were observed in pollen germination and pollen tube growth at different temperatures.  相似文献   
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