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101.
Mohsen?MardiEmail author Hermann?Buerstmayr Behzad?Ghareyazie Marc?Lemmens Nooshin?Moshrefzadeh Peter?Ruckenbauer 《Euphytica》2004,136(1):45-50
Fusarium head blight (FHB) caused by Fusarium spp. is one of the most important fungal diseases of wheat (Triticum aestivum L.) in regions with wet climatic conditions. Improvement of the FHB resistance by developing new varieties requires sound knowledge on the inheritance of resistance. An 8 × 8 diallel analysis was performed to estimate general (GCA) and specific (SCA) combining ability of resistance to FHB. The F1s and parental lines were evaluated under artificial inoculation at the experimental field of IFA-Tulln, Austria during 2001 and 2002. Disease severity was evaluated by repeated scoring of the percentage of infected spikelets and calculating an area under the disease progress curve (AUDPC). The analysis of combining ability across two years showed highly significant GCA and non-significant SCA effects indicating the importance of additive genetic components in controlling FHB resistance. The significant GCA-by-year interaction presented the role of environmental factors in influencing the FHB reaction of wheat lines. The comparison of the crosses with low FHB infection and GCA effects of their parents showed that such crosses involved at least one parent with high or average negative GCA effect. The results revealed that it is feasible to use highly or moderately resistant genotypes and conventional breeding methods to achieve genetic improvement of FHB resistance in spring wheat. 相似文献
102.
Potassium (K+) directly released from primary K‐bearing minerals can contribute to plant nutrition. The objective of this research was to assess short‐term K+ release and fixation on a range of intensively cropped calcareous soils. Potassium sorption and desorption properties and the contributions of exchangeable‐K+ (EK) and nonexchangeable‐K+ (NEK) pools to K+ dynamics of the soil‐solution system was measured using a modified quantity‐to‐intensity (Q : I) experiment. Release and fixation of K+ were varied among soils. The relation between the change in the amount of NEK during the experiment and the initial constrain was linear, and soil ability for K+ release and fixation (β) for all soils varied from 0.041 to 0.183, indicating that 4% to 18% of added K+ converted to NEK when fixation occurred. The equilibrium potential buffering capacity (PBC) for K+ derived from Q : I experiments had significant correlation (r = 0.75, p < 0.01) with β, indicating that PBC depends not only on exchange properties but also on release and fixation properties. The depleted soils showed higher β value than the other soils, indicating much of the added K+ was converted to NEK in case of positive constraint. The range of the amount of EK which was not in exchange equilibrium with Ca (Emin) in the experimental conditions was large and varied from 0.68 to 9.00 mmol kg–1. On average, Emin amounted to 64% of EK. This fraction of EK may not be available to the plant. The parameters obtained from these short‐term K+ release and fixation experiments can be used in plant nutrition. 相似文献
103.
Javad Sadeghinezhad Zahra Ganji Sirous Sadeghian Chaleshtori Hadis Bojarzadeh Mahdi Aghabalazadeh Asl Ali Bayat Khomejini Ehsan Roominai Mohsen Hosseini Margherita De Silva 《Anatomia, histologia, embryologia》2021,50(6):1026-1033
Sheep have been used as translational models of human postnatal testicular development. However, the morphometric features of the normal developing testis in sheep embryos have not been previously investigated using stereology. The objective of the present work was to establish normal quantitative parameters for fetal testicular tissue components in sheep, using unbiased design-based stereological methods. Twenty-four sheep embryos were divided into four gestational age groups (9–11, 12–14, 15–17 and 18–20 weeks of gestation) on the basis of the embryos’ crown-rump length. Isotropic, systematic uniform random sections of the left testes were obtained by employing the orientator method. Testicular total volume, the absolute and proportional volumes occupied by the seminiferous tubules and interstitial tissue, as well as the seminiferous tubule length, were estimated using the point-counting system and the unbiased counting frame principle. All the parameters, with the exception of the interstitial tissue's fractional volume, gradually increased along with gestational age, with the maximum increase especially seen in the late fetal stages. The proportional volume of the interstitial tissue, on the other hand, showed a decreasing trend along with increasing gestational age. The absolute volume of the testes, of the seminiferous tubules and of the interstitial tissue, and the length of the seminiferous tubules showed a significant (p< 0.05) positive linear correlation with gestational age. Several similarities were observed with human testicular embryogenesis. The stereological data emerging from the present study might prove useful as basic contribution to the fields of andrology and embryology and stimulate further research in these areas. 相似文献
104.
105.
Namazi F Namavari MM Rahimi E Lotfi M Tahamtan Y 《Veterinary research communications》2011,35(7):425-431
The Apicomplexan parasite Besnoitia caprae infects wild and domestic goats. Knowledge on Besnoitia caprae specially an optimized animal model is sparse. Experimental infections with tachyzoites of BC-Pars obtained from BALB/c mice
were conducted in outbred mice to determine the infectivity and LD50 of Besnoitia caprae. Six groups of five mice were intraperitoneally infected with 12.5 × 103, 25 × 103, 5 × 104, 1 × 105 and 2 × 105 tachyzoites and a control inoculum of DMEM, respectively. Although morbidity and mortality were observed in all groups, two
mice in the 12.5 × 103 group showed alopecia and skin lesions on 60 days post-infection (DPI). Histopathological and molecular examination of skins
confirmed B. caprae infection. The LD50 was calculated as 25 × 103.2 tachyzoites per mouse. The results indicate that outbred BALB/c mice can be used as a suitable model of besnoitiosis and
to screen candidate treatments and to test the efficacy of vaccines for besnoitiosis. 相似文献
106.
Effects of foliar application of some macro- and micro-nutrients on tomato plants in aquaponic and hydroponic systems 总被引:1,自引:0,他引:1
An aquaponic system was designed to investigate effects of foliar applications of some micro- and macro-nutrients on tomato growth and yield in comparison with a hydroponic system. Common carp, grass carp and silver carp were stocked in the rearing tanks at 15, 20 and 15 fish m−3, respectively. The fish were fed three times daily with a pellet diet containing 46% protein. Fourteen days old tomatoes seedlings were transplanted on to growth bed units of aquaponic and hydroponic systems after stocking of carp fish for 2.5 months in the rearing tanks. Foliar nutrients application began 30 days after transplantation. Eight treatments were used, untreated control, foliar application at the rate of 250 mL plant−1 with 0.5 g L−1 K2SO4, MgSO4·7H2O, Fe-EDDHA, MnSO4·H2O, H3BO3, ZnCl2, and CuSO4·5H2O. Plants were sprayed twice a month. The results showed that biomass gains of tomatoes were higher in hydroponics as compared to aquaponics. Foliar application of K, Mg, Fe, Mn, and B increased vegetative growth of plants in the aquaponics. In the hydroponics, only Fe and B had positive effects on plant growth. Cluster number per plant in aquaponics was lower than in hydroponics treatments, but it increased with foliar application of elements. There was no difference in fruit number and yield between aquaponics and hydroponics grown plants in the control treatments. Except Cu, foliar spray of all elements significantly increased plant fruit number and yield in the aquaponics in order of: K > Fe > Mn > Zn > Mg > B. In the hydroponics, foliar application of K, Mg and Zn increased fruit number and yield of plants compared to control. These results indicated that foliar application of some elements can effectively alleviate nutrient deficiencies in tomatoes grown on aquaponics. 相似文献
107.
Journal of Soils and Sediments - Sb is a metalloid that naturally occurs in traces in the Northern German Lowland Area, only. Its frequent and still growing demand for industrial purposes and its... 相似文献
108.
AbstractIn Iran, the recent spike in herbal medicines has led to a corresponding price increase. Therefore, these montane species are now widely field cultivated. Medicinal plant consumers strongly prefer organically grown plants, and farmers are responding to this market. However, the effects of organic amendments on medicinal plant nutrient content and yield have been poorly studied. Therefore, this study measured the effects of different organic treatments on the growth of fenugreek and goat pea. Plants were grown to compare the effects of composted municipal waste (CMW), vermicompost (VC), and urea nitrogen (N) to untreated field soil (C0). Germination percentage was significantly higher in urea N (76.5%), CMW (75.5%), and VC (51.6%) compared to C0 (36.3%). Fenugreek performed better in organic amendment treatments than goat pea. Urea N also increased fenugreek plant dry matter significantly compared to C0, but this increment was not as high as CMW or VC. Plants grown in VC had higher whole plant N content (3.2%) than those grown in CMW (2.8%) and plants grown in urea N (2.6%). Plants treated with CMW (8613?mg kg?1) and VC (8503?mg kg?1) had a significantly higher P content than those treated with N (7430?mg kg?1) or C0 control grown (7236?mg kg?1). Application of VC significantly increased plant K content (2483?mg kg?1) compared to CMW (1850?mg kg?1), N (1750?mg kg?1), and C0 control (1716?mg kg?1). Even without fertilization, both plant species contained a considerable amount of micronutrient elements. 相似文献
109.
To evaluate yield loss models in safflower–redroot pigweed systems, two field experiments were conducted during the 2007 and 2008 growing seasons. The relative yield loss of the crop was recorded in plots laid out in a split-plot design with three irrigation treatments as main plots [100, 75 and 50% FC (field capacity)] and five weed densities (0, 3, 6, 9 and 12 m?2) as subplots in three replicates. Among Cousens, Spitters, and Kropff & Lotz models, Spitters was the best predictor of yield loss and showed the lowest RMSE (0.001–0.002), high Adj-R 2 (0.824–0.929), highest precision (0.962–0.981) and accuracy (constant and systematic biases of 0.000–0.103 and 0.863–1.040, respectively), and random residuals plot. The Cousens, and Kropff & Lotz models showed relatively good fit, although they had higher RMSE values, larger constant and systematic biases, and nonrandom residual plots. The reliability of all models was influenced by irrigation treatment, with generally larger constant and systematic biases at 50% irrigation, causing yield loss under/overprediction under 100 and 50% irrigation, respectively. The parameters of the Spitters model correctly explained the biological function of water shortage on yield response; however, the parameters of other models failed to represent a biologically acceptable yield response function, particularly at 50% irrigation. 相似文献
110.
Khosro Mohammadi Gholamreza Heidari Mohsen Javaheri Mohammad Tahsin Karimi Nezhad 《Archives of Agronomy and Soil Science》2013,59(7):899-910
Tillage systems and fertilization have important effects on soil microorganism activity. Information regarding the simultaneous evaluation of long-term tillage and fertilization on soil microbial traits in sunflower fields is not available. Therefore, this study was conducted to determine the best tillage and fertilization system for soil microbial parameters. The experimental design was a split plot based on a randomized complete block design with three replications. Main plots consisted of the long-term tillage systems (1999–2011) including: no tillage (NT), minimum tillage (MT) and conventional tillage (CT). Six methods of fertilization, including farmyard manure (N1), compost (N2), chemical fertilizers (N3), farmyard manure + compost (N4); farmyard manure + compost + chemical fertilizers (N5), and control (N6) were arranged in subplots. Results showed that the highest amount of microbial biomass was observed in treatment NTN4. The highest and lowest values of enzyme activities (acid, alkaline phosphatase, urease, dehydrogenase and protease) were found in organic fertilizers + NT and chemical fertilizers + CT plots, respectively. Highest basal and induced respiration values were found for NTN4 treatment. Correlation coefficients between enzyme activity, respiration and microbial biomass carbon were significant. 相似文献