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11.
N. Mohammadi H. Puralibaba E. Mohammadi Goltapeh A. Babaie Ahari B. Pakdaman Sardrood 《Phytoparasitica》2012,40(1):69-76
Fusarium oxysporum f. sp. lentis is the most important pathogen of lentil plants, and most areas under lentil cultivation are reported to have a fusarium
wilt disease background. The plants are infected in the seedling stage and later stages of their development. Fusarium wilt
disease, which has appeared at high incidence rates during recent years, has caused sharp drops in the yield, especially in
Moghan, in the northwest of Iran. Forty-five isolates of the pathogen were collected from different regions of the country
with two isolates from ICARDA in the summer of 2008 and identified using Nelson’s key. The pathogenicity of the collected
isolates was studied on a sensitive line (ILL 4605) under greenhouse conditions and significant differences in pathogenicity
were found among them. The most pathogenic isolates from three provinces, East Azerbaijan (EA 30), Ardebil (Ar 3) and Khorasan
(Kh 45), were selected and used in screening of 55 developed lines under greenhouse and field conditions. In the greenhouse,
test plants were inoculated by immersing root tips in spore suspension and sowing seeds in pre-infested pot soil. Field tests
were carried out in a naturally highly infested farm. At all stages, the plant response to the disease was based on the percentage
of dead plants. Cluster analyses of the greenhouse and field data led to the selection of three lines (81S15, FLIP2007-42 L
and FLIP2009-18 L) that were resistant under greenhouse and field conditions. 相似文献
12.
Hossein Mohammadi Mohammad Moradi Shahrebabak Mahmood Vatankhah Hossein Moradi Shahrebabak 《Tropical animal health and production》2012,45(1):185-191
Genetic parameters and genetic trends for birth weight (BW), weaning weight (WW), 6-month weight (6MW), and yearling weight (YW) traits were estimated by using records of 5,634 Makooei lambs, descendants of 289 sires and 1,726 dams, born between 1996 and 2009 at the Makooei sheep breeding station, West Azerbaijan, Iran. The (co)variance components were estimated with different animal models using a restricted maximum likelihood procedure and the most appropriate model for each trait was determined by Akaike’s Information Criterion. Breeding values of animals were predicted with best linear unbiased prediction methodology under multi-trait animal models and genetic trends were estimated by regression mean breeding values on birth year. The most appropriate model for BW was a model including direct and maternal genetic effects, regardless of their covariance. The model for WW and 6MW included direct additive genetic effects. The model for YW included direct genetic effects only. Direct heritabilities based on the best model were estimated 0.15?±?0.04, 0.16?±?0.03, 0.21?±?0.04, and 0.22?±?0.06 for BW, WW, 6MW, and YW, respectively, and maternal heritability obtained 0.08?±?0.02 for BW. Genetic correlations among the traits were positive and varied from 0.28 for BW–YW to 0.66 for BW–WW and phenotypic correlations were generally lower than the genetic correlations. Genetic trends were 8.1?±?2, 67.4?±?5, 38.7?±?4, and 47.6?±?6 g per year for BW, WW, 6MW, and YW, respectively. 相似文献
13.
Majid Rostami Reza Mirzaei Talarposhti Hoda Mohammadi Michael Scott Demyan 《Communications in Soil Science and Plant Analysis》2019,50(10):1250-1257
A field study was conducted during 2015–2017 in order to evaluate effects of the foliar application of different sources and concentrations of zinc oxide (ZnO) on the yield and morpho-physiological characteristics of saffron. Experimental treatment included the foliar application of nano ZnO at a concentration of (3, 6, and 9 g L?1), foliar application of normal ZnO at a concentration of (3, 6, and 9 g L?1) and the control. Both types of ZnO had positive effects on the saffron yield and number of flowers, but the highest yield and flower number were obtained by the foliar application of 9 g L?1 normal ZnO followed by 6 g L?1 nano ZnO. Increasing concentrations of both fertilizers up to 3 g L?1 had no significant effect on crocin, but the crocin content significantly decreased at higher concentrations. Effects of experimental treatments were significant on all morpho-physiological traits. The maximum chlorophyll a (1.74 mg.g?1) was observed in normal ZnO at a concentration of 9 g L?1 followed by nano ZnO at a concentration of 3 g L?1. The increasing application of different types of fertilizers linearly increased the Peroxidase activity, but the highest activity of Catalase in normal ZnO and nano ZnO was measured after the foliar application at concentrations of 3 and 6 g L?1, respectively. 相似文献
14.
Pollen and trichome morphology of the genus Betula were evaluated from three main habitats in Iran using light and electron microscopy.Pollen types were identical and tri-porate;however,in terms of quantitative data,some differences were observed in exine(outside)wall thickness,length of polar axis and length of equatorial axis,possibly due to the environment.Pollen alone is insufficient to separate species of Iranian birch.Investigation of the trichome trait(small hairs or other outgrowths)revealed that birch species in Iran belong to:(1)Betula litwinowii Doluch.according to the low density of trichomes on the adaxial surface of the leaves and the lack of trichomes on the abaxial surface and many trichomes on the petioles;(2)Betula pendula Roth.due to the absence of trichomes on the adaxial surface and the low density of trichomes on the abaxial surface;and,(3)in the adaxial and abaxial surfaces of leaves and petioles,the trichomes had different types of pilose(long,soft hairs),and this strengthens the possibility of a different species or more likely a hybrid of B.pendula. 相似文献
15.
The purpose of this study was to define the structures of the digits and hoof in Holstein dairy cattle by using computed tomography scan (CT scan). Transverse, sagittal and dorsoplantar CT images of two isolated cattle cadaver digits were obtained using a Siemens ARTX2 Somatom. The CT images were compared to corresponding frozen cross-sections. Relevant anatomical structures were identified and labelled at each level. The CT images provided anatomical detail of the digits and hoof in Holstein dairy cattle. Transversal images provided excellent depiction of anatomical structures when compared to corresponding frozen cross-sections. The information presented in this paper would serve as an initial reference to the evaluation of CT images of the digits and hoof in Holstein dairy cattle. 相似文献
16.
17.
Leila Behbood Soroush Karimi Esmaeil Mirzaei Ghobad Mohammadi Mahsa Azami Elham Arkan 《Fibers and Polymers》2018,19(7):1454-1462
The mucoadhesive Chitosan (CS) nanofibers as a drug delivery system were developed. Chitosan was modified via the immobilization of thiol groups from L-cysteine as a mucoadhesive reagent. The mucoadhesive properties of the chitosan nanofibers were evaluated by tensiometer set and via tensile studies. Drug and mucoadhesive agent loading lead to decrease diameters and increased porous of nanofibers. The release of Tetracycline (Tet) and Triamcinolone (Tri) were increased with increasing immersion time and it became constant at long immersion times. Mucoadhesion studies were done at pH 2–7 and in pH 6 maximum mucoadhesive properties observed. Release studies demonstrated a sustained release of both drug continued up to 48 hours. Microbial studies were performed on the nanofibers. The drug delivery system represented a novel tool for improve the therapeutic efficacy of various drugs that are poorly absorbed from the gastrointestinal tract. Also it is an efficient system for treatment of oral ulceration. 相似文献
18.
Razmi GR Mohammadi GR Garrosi T Farzaneh N Fallah AH Maleki M 《Veterinary parasitology》2006,135(2):187-189
A seroepidemiology study of Neospora caninum was conducted in Mashhad area, Khorasan province, Iran on 337 cattle from 30 dairy using ELISA. All herds had seropositive cattle and antibodies were formed in 46% of the cattle. Abortion was significantly associated with seropositivity of cattle. The highest risk of abortion was observed in the 1-2-year-old cows. Our results indicate that Neospora infection is widespread in Iran. 相似文献
19.
The present investigation was carried out to estimate the interrelationships and repeatabilities of various variability parameters,
i.e., genotypic (σ2g) and phenotypic (σ2p) variances, genotypic (GCV) and phenotypic (PCV) coefficients of variation, broad-sense heritability (hb2), genetic advance (GA), and genetic gain (GG), using data derived from a number of plant characters [seed yield (SY), days
to heading (DH) and maturity (DM), plant height (PH), and thousand kernel weight (TKW)] of 17 spring safflower genotypes grown
in 27 environments in Iran during 2003–2005. The analysis of variance for the five characters revealed significant differences
among the genotypes in most of the environments, indicating a very high variability within the genotype. High genotypic and
phenotypic variances in the quantitative traits, particularly for SY, were markers of increased success. A close correlation
between GCV and PCV was observed for all the traits, indicating that all of the characters were less influenced by the environment
and that the variability which exists in these characters is under genetic influence; however, the relatively higher values
of PCV indicate the predominant role of environment. High expected genetic advances were observed for SY, but this trait showed
large fluctuations in different environments (97.4%). High and low mean values of heritability were observed for DH (74.3%)
and SY (59.7%), respectively, whereas high and low mean values of genetic gain were found for SY (60.3%) and DM (4.2%), respectively.
High heritability coupled with low GA as a percentage of the mean was observed for DH and MD, whereas moderate heritability
with moderate GA as a percentage of the mean was exhibited for SY. Analysis of correlation among the parameters showed that
they were strongly and constantly correlated with each other, but none of them were consistently well correlated with the
heritability parameter (hb2). Based on estimates of the genetic variability parameters within each trial, the ranking of genotypes in the low-performance
subset for all traits differed from that in the high-performance subset. This result indicates poor repeatability for the
genetic variability parameters. The estimates of the parameters in the multi-year trials were almost constant and repeatable,
whereas the responses over years showed poor repeatability. 相似文献
20.