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61.
Cultivated wheat, (Triticum aestivum L.), is one of the most important food crops in the world. The Aegilops L. genus is frequently utilized by plant breeders for improving the current wheat cultivars due to their close relationships. Therefore, understanding the phylogenetic relationships among the species of these genera is not only valuable for plant taxonomy, but also for plant breeding efforts. The presented phylogenetic analysis was based on the sequences of trnT-F chloroplast DNA containing three non-coding sub-regions. Twelve genotypes belonging to four species of Triticum L. genus and twenty-four genotypes belonging to eight species of Aegilops genus were used in the current study. The results postulated a close genetic relationship between diploid Aegilops species containing the BB genome and polyploid Triticum species. With the exception of Aegilops cylindrica Host (CCDD), all other Aegilops species having the CC genome were alienated from Aegilops speltoides Tausch (BB) and clustered together. These two clusters joined by a third cluster including the AA genome containing diploid Triticum species.  相似文献   
62.
Although many states recommend boron (B) fertilizer for many field crops, information about B toxicity of canola is lacking. This experiment was carried out at Central Anatolia, Turkey from 2002 to 2003, to determine genotypic range in B efficiency of eight spring canola cultivars, to identify the B-inefficient cultivars and to identify specific responses. The cultivars were grown under B moderate deficiency (extractable B 0.56 mg kg?1) and toxic B applied (15 kg B ha?1) conditions. According to the results, seed yield varied significantly among the cultivars and B application decreased the seed yield by 31% on average. Also, toxic B application reduced protein and oil contents similar to seed yield, and increased leaf B concentration in all varieties. This study has shown that leaf B concentration has increased considerably when B is applied to Pactol and Star cultivars, but seed yield of +B and ?B has not shown significantly a change. It is possible to say that Star and Pactol—which have not been affected by the toxic B application—are genotypes that are tolerant to B toxicity and may be cultivated at B toxic lands.  相似文献   
63.
The effects of months of the year and nitrogen (N) sources on salad rocket (Eruca sativa Mill.) yield, quality, and nitrate accumulation was investigated during the years 2002 and 2003. In both years, seeds were sown on the first day of April, May, June, July, August and September. Three different nitrogen sources were used: farmyard (cattle) manure (100 tonnes·ha?1), calcium nitrate [Ca(NO3)2]-15.5% N (150 kg N·ha?1) and ammonium sulfate [(NH4)2SO4)]-21% N (150 kg N·ha?1). Yield, leaf color, dry matter, vitamin C and total glucosinolate content and nitrate accumulation was assessed. Growing months affected all the assessed parameters significantly both years, with the exception of hue angle in 2003, whereas nitrogen source only influenced yield and nitrate accumulation in 2003. In both years the highest yield was obtained in April, but vitamin C and total glucosinolate contents were higher during summer months, and leaves were slightly darker colored. Chemical fertilizers increased the yield compared to farmyard manure; however, they also increased nitrate accumulation slightly, without any significant difference between them. Nitrate accumulation never exceeded 300 mg kg?1 fresh weight (FW), which is well below the acceptable daily intake of 3.7 mg nitrate per kg?1 bodyweight set by European Commission's Scientific Committee on Food.  相似文献   
64.
Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey.  相似文献   
65.

The purpose of this research is to perform the energy use efficiency and greenhouse gas (GHG) emissions of pistachio production. This research was performed for 2016 and 2017 production season in Ad?yaman province of Turkey in dry conditions in 2017. The data supplied from research were collected from 152 different farms by face to face surveys with simple random sampling method. The agricultural input energies and output energies used in pistachio production were computed to determine the energy use efficiency. According to the research findings, the energy inputs in pistachio production were computed respectively as 4561.11?MJ ha?1 (35.50%) diesel fuel energy, 3206.24?MJ ha?1 (24.96%) chemical fertilizers energy, 2420.93?MJ ha?1 (18.84%) machinery energy, 1020.06?MJ ha?1 (7.94%) human labour energy, 715.69?MJ ha?1 (5.57%) animal labour energy, 656.95?MJ ha?1 (5.11%) farmyard manure energy and 266.16?MJ ha?1 (2.07%) chemicals energy. Total input energy was computed as 12,847.14?MJ ha?1. Energy values of pistachio yield were computed as 15,008.65?MJ ha?1. Energy use efficiency, specific energy, energy productivity and net energy computations were computed respectively as 1.17, 22.32?MJ kg?1, 0.04?kg MJ?1 and 2161.51?MJ ha?1. The consumed total energy input in pistachio production can be classified as 49.01% direct, 50.99% indirect, 18.62% renewable and 81.38% non-renewable. Total GHG emission was computed as 1123.72?kg CO2?eqha?1 for pistachio production with the greatest portions for human labour (32.42%). The human labour followed up chemical fertilizers usage (23.21%), diesel fuel consumption (19.89%), machinery usage (15.30%), farmyard manure usage (5.65%), chemicals usage (3.25%) and animal labour usage (0.27%), respectively. Additionally, GHG ratio value was computed as 1.95 kgCO2?eqkg?1 in pistachio production.

  相似文献   
66.
Soil pH is one of the main factors influencing the solubility and availability of trace elements in arable soils. Thus pH can affect the trace element contents of agricultural crops and thereby indirectly influence human health. The aim of this study was to determine Cd, Ni, Zn, Cu, Mn, Cr, Al and Se contents in spring wheat, potatoes and carrots (Cd, Ni and Zn) and estimate their correlations with certain soil factors (surface and subsurface soil pH and organic matter content) governing the plant availability of these elements. Commercial fields were sampled in Sweden in order to cover a wide range of soil types with respect to pH, soil texture and organic matter content. Concentrations of Zn, Mn, Ni (grain) and Cd (straw) in spring wheat (n=43); Cd, Ni, Zn, Mn, Cu and Al in potatoes (n=69); and Cd, Ni and Zn in carrots (n=36) showed significant negative correlations with surface soil pH (0–25 cm). The Se content of potatoes and Cr content of spring wheat straw were positively correlated with soil pH. Stepwise multiple regressions including a combination of soil pHs (0–25 and 25–50 cm) and organic matter contents (0–25 cm) showed that the organic matter content as well as the surface and subsurface soil pH significantly influenced concentrations of several trace elements in one or more of the studied crops. It was concluded that, if acid deposition together with other acidifying processes (fertilisation, harvest of biomass, etc.) are not balanced by a sufficient amount of liming there might be a decrease in the pH of arable soils, which, in turn will lead to decreased levels of Se in edible crops but an overall increase concentrations of other trace elements.  相似文献   
67.
The cement industry has been one of the major sources of air pollution in the past and the Turkish Air Quality Protection Regulation has issued limits also to trace elementemissions to minimise the polluting effects of this industrialsector. In the present study, dust samples were obtained isokinetically from 18 main stacks of 10 cement plants locatedin different geographical areas of Turkey. The samples were analysed for trace elements Hg, Cd, Cr, Pb, Ni, Se, Te, TI, V, Sb, Ba, Zn, Co, Sr, Cu, Bi, Mo, Be, and As. The results are presented both as concentration in the dust samples as well as emissions per unit production, and concentration inthe stack gas. The trace element emissions of the main stacksagree to great extent with the values given in the literature. On the other hand, the trace element emissions of the plants considered are well below the limits set in the Turkish Air Quality Protection Regulation.  相似文献   
68.
1. The influence of the shell membranes on shell strength was studied in 21 Single Comb White Leghorn eggs.

2. Shell deformation and shell thickness were plotted for each egg and the regression line was calculated. The difference between the observed shell deformation and that predicted by the regression line was calculated for each egg and this distance, with changed sign, was called the shell deformation index.

3. The force needed to separate the shell membranes from a 10 mm wide strip of the shell was determined by a tensile testing machine and was termed attachment strength.

4. The correlation between shell deformation index and attachment strength was highly significant (r=0.88, P<0.0005). Thus the shell membranes contribute to shell strength, probably by serving as a reinforcement of the crystalline part of the shell.  相似文献   

69.
Tropical Animal Health and Production - The primary objective of the present study was to assess the effects of vitamin and mineral premix (VMP) withdrawal from the diets 30 and 60&nbsp;days...  相似文献   
70.
Hazelnut (Corylus avellana L.) is mostly grown in rainfed condition in Turkey as well as other some countries in the world without more yield reduction. However, there is not enough information about how to give yield without more reduction in rainfed hazelnut orchard. In an endeavor to search this question, quantifications of leaf water potential (LWP), stomatal conductance (gs) and photosynthetically active radiation (PAR) of hazelnut tree were investigated in rainfed hazelnut orchard in the summer of 2013 and 2014. Additionally, possible effects of those quantifications on rainfed hazelnut trees vs. soil water content (SWC) was investigated. Results of this study exhibited that yearly ET (evapotranspiration) of rainfed hazelnut trees was higher in 2014 than 2013 even though seasonal ET of rainfed hazelnut trees was higher in 2013 than 2014. Hence, yield, LWP and gs were higher in 2014 than 2013 but PAR and SWC (even all the study season) were mostly higher in 2013 than 2014. Moreover, relationships of LWP, gs and PAR and responses of LWP, gs and PAR to SWC were non stronger. These differences could be attributed differences of climate variability such as precipitation and temperature during the observed period throughout the season in the studied years. However, rainfed hazelnut trees may be required supplement irrigation in dry summer, such as year of 2013, to avoid summer water stress. Finally, it can be concluded that hazelnut trees can be grown well and give normal yield for the areas which have about 950 mm precipitation.  相似文献   
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