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The aim of this study was to seek optimum seed germination temperature of Lentil seeds. Germination tests were conducted for twenty-four genotypes with 3 replicates in a completely randomized design, were conducted to investigate germination behavior of lentil seeds subjected to six different heat temperatures (39, 46, 54, 61, 68 and 75°F) and duration on germination. The experiment results revealed that different temperature treatments were effective on mean germination percentage and suggested that there is relationship between the temperature treatment and germination rate. The mean germination was obtained for 39, 46, 54, 61, 68 and 75°F, 0.945, 1.590, 1.864, 2.305, 2.840 and 2.573 respectively. The experiment revealed that the different temperature treatments were effective on mean germination percentage and seeds germinated faster at higher constant temperatures and optimum germination occurred at 68°F. 相似文献
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Maryam Nosrati Hojjat Asadollahpour Nanaei Zeinab Amiri Ghanatsaman Ali Esmailizadeh 《Reproduction in domestic animals》2019,54(2):358-364
Ovulation rate and prolificacy are the most important reproductive traits that have major impact on the efficiency of lamb meat production. Here, we compared the whole genomes of the Romanov sheep, known as one of the high prolific breeds, and four other sheep breeds namely Assaf, Awassi, Cambridge and British du cher, to identify genetic mechanisms underlying prolificacy in sheep. Selection signature analysis revealed 637 and 477 protein‐coding genes under positive selection from FST and nucleotide diversity (Pi) statistics, respectively. Further analysis showed that several candidate genes including LEPR, PDGFRL and KLF5 genes are involved in sheep prolificacy. The identified candidate genes in the selected regions are novel and provide new insights into the genetic mechanisms underlying prolificacy in sheep and can be useful in sheep breeding programmes to develop improved breeds for high reproductive efficiency. 相似文献
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Seyed Saeid Hojjat 《Russian Agricultural Sciences》2013,39(2):134-142
One hundred lentil genotypes accessions of Mashhad Lentil Collection (MLC) were evaluated at Chenaran, Iran with three planting dates [10 Oct., 10 Nov. (fall) and 28 Mar. (spring) during 2008/09 growing seasons]. Evaluation based on winter survival percentage showed that in 2008/09 growing season, percentage of highly tolerant, tolerant, moderately tolerant, moderately susceptible and susceptible genotypes were 22, 61, 16, 1 and 0 respectively. In the first planting date more than 50% of genotypes were ranked as highly tolerant, however it was decreased to 12% and 5% of genotypes in the second and third planting dates, respectively, in this year. According to the fall plantings data, the length of growth duration of samples in fall plantings were 2.3 times higher than spring planting, and also in the first planting that was 5, 25 and 255 percent more than 2nd and 3rd planting dates, respectively. The height of fall plants were more than spring plants and in the first year fall planting genotypes were about 38% taller than the same planting. The number of pod per plant in fall planting was 2 times higher than spring planting. More than 22% of accessions had 125 pods per plant in 1st and 2nd planting in this year. In the 2008/09 growing seasons the yield of lentil genotypes in fall planting were more than 4 and about 2 times of spring planting, respectively. In the 2008/09 growing seasons 39% of spring planting samples produced less than 50 gr/m2 seed yield. It seems that the improvement of seed yield in the fall planting were due to suitable winter survival of plants fallowed by better usage of rainfall and escaping from drought and heat stress of the end of spring. Results showed that there were some cold tolerant accessions in MLC and it is possible to provide cold tolerant cultivars for fall planting in Mashhad conditions. 相似文献
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Amiri Z Mohammad K Mahmoudi M Zeraati H Fotouhi A 《Pakistan journal of biological sciences: PJBS》2008,11(8):1076-1084
This study is designed to assess the application of neural networks in comparison to the Kaplan-Meier and Cox proportional hazards model in the survival analysis. Three hundred thirty gastric cancer patients admitted to and surgically treated were assessed and their post-surgical survival was determined. The observed baseline survival was determined with the three methods of Kaplan-Meier product limit estimator, Cox and the neural network and results were compared. Then the binary independent variables were entered into the model. Data were randomly divided into two groups of 165 each to test the models and assess the reproducibility. The Chi-square test and the multiple logistic model were used to ensure the groups were similar and the data was divided randomly. To compare subgroups, we used the log-rank test. In the next step, the probability of survival in different periods was computed based on the training group data using the Cox proportional hazards and a neural network and estimating Cox coefficient values and neural network weights (with 3 nodes in hidden layer). Results were used for predictions in the test group data and these predictions were compared using the Kaplan-Meier product limit estimator as the gold standard. Friedman and Kruskal-Wallis tests were used for comparisons as well. All statistical analyses were performed using SPSS version 11.5, Matlab version 7.2, Statistica version 6.0 and S_PLUS 2000. The significance level was considered 5% (alpha = 0.05). The three methods used showed no significance difference in base survival probabilities. Overall, there was no significant difference among the survival probabilities or the trend of changes in survival probabilities calculated with the three methods, but the 4 year (48th month) and 4.5 year (54th month) survival rates were significantly different with Cox compared to standard and estimated probabilities in the neural network (p < 0.05). Kaplan-Meier and Cox showed almost similar results for the baseline survival probabilities, but results with the neural network were different: higher probabilities up to the 4th year, then comparable with the other two methods. Estimates from Cox proportional hazards and the neural network with three nodes in hidden layer were compared with the estimate from the Kaplan-Meier estimator as the gold standard. Neither comparison showed statistically significant differences. The standard error ratio of the two estimate groups by Cox and the neural network to Kaplan-Meier were no significant differences, it indicated that the neural network was more accurate. Although we do not suggest neural network methods to estimate the baseline survival probability, it seems these models is more accurately estimated as compared with the Cox proportional hazards, especially with today's advanced computer sciences that allow complex calculations. These methods are preferable because they lack the limitations of conventional models and obviate the need for unnecessary assumptions including those related to the proportionality of hazards and linearity. 相似文献
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Saiepour N Mohammad K Abhari R Zeraati H Noorbala AA 《Pakistan journal of biological sciences: PJBS》2008,11(5):809-812
The aim of this study was to investigate the association between mental disorder and back pain among postmenopausal Iranian women. Three thousand six hundred and fifty five postmenopausal women were interviewed in the second National Health Survey (2nd NHS) in the year 2000, in Iran. Of whom, 2953 women were included in this study. Back pain (BKP) was considered as dependent variable and mental disorder as independent variable. Factors like age, Body Mass Index (BMI), residential area, employment, literacy, smoking habit, marital status and spinal fractures were considered as confounders. Logistic regression models have been applied for data analysis. The BKP prevalence was 40.1% and the prevalence of mental disorder was 44.3%. After adjustment for confounders, mental disorder was positively associated with BKP, OR (CI): 1.615 (1.36, 1.91). This study confirmed that BKP and mental disorder are common problems and these two factors are associated amongst postmenopausal women. Further longitudinal studies are recommended to specify casual inferences. 相似文献
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Ruiz-Larrañaga Otsanda Asadollahpour Nanaei Hojjat Montes Iratxe Ayatollahi Mehrgardi Ahmad Abdolmohammadi Alireza Kharrati-Koopaee Hamed Sohrabi Saeed S. Rendo Fernando Manzano Carmen Estonba Andone Iriondo Mikel Esmailizadeh Ali 《Tropical animal health and production》2020,52(5):2283-2290
Tropical Animal Health and Production - Genetic structure and genetic diversity levels of indigenous Iranian sheep breeds are not clear, despite the interest this region has in itself as an... 相似文献
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The two-spotted spider mite, Tetranychus urticae Koch, is a very polyphagous pest with a worldwide distribution. In order to appraise population growth parameters of this
pest, samples of two-spotted spider mites were taken from soybean (Glycine max) fields of Moghan region, Iran in June 2007 and are reared on bean plants var. Derakhshan (Phaseolus vulgaris) in a growth chamber. The life table parameters of this pest were calculated on three commercial soybean cultivars (Zane,
Hach, and L17) and one hybrid (Hob × Will) at 25 ± 1°C, 60 ± 10%RH, and 16 h photophase. The developmental times of immature
stages varied from 9.69 on Hach to 9.82 days on L17, whereas the immature survival was 57–79% on Hach and Hob × Will, respectively.
On average, there were 65.5, 40.8, 38.8 and 34 eggs produced per female on L17, Hach, Hob × Will and Zane, respectively. The
intrinsic rate of natural increase (r
m
) for T. urticae on Hob × Will was the highest, whereas the values for r
m
ranged from 0.211 (females/female/day) on Zane to 0.292 on Hob × Will. Also, jackknife values of other life table parameters
such as net reproductive rate (R
0), generation times (T), doubling time (DT), and finite rate of increase (λ) on these cultivars were estimated. Overall, the two-spotted spider mite indicated a better performance on Hob × Will than
on the other soybean cultivars. 相似文献
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A study was conducted to evaluate the effect s of silver nanoparticles for ameliorating negative effects of salinity on germination and growth of Fenugreek seeds. In order to investigate salinity stress on Fenugreek germination indices, an experiment was carried out in Iran from October 2014 to November 2014 at Ferdowsi University of Mashhad, in the biotechnology Laboratory, to create salinity stress, sodium chloride (NaCl) at the levels of 0 (as control), 5, 10, 15 and 20 dS/m and Five levels of silver nanoparticles (0, 10, 20, 30 and 40 μg mL–1) on Fenugreek seed (Trigonella foenum-graecum); were tested Germination characteristics such as total germination (GT), Germination Speed Index (GSI), Shoot and Root of seedling long, Fresh Mass and Dry Mass were measured. Results showed the great effects of silver nanoparticles to improve salinity stress on Fenugreek seed germination. Results showed a significant reduction in germination percent and seedling growth due to the salinity stress while significantly increased with silicon nano-particles application. In without silver nanoparticle low level of salinity (0 dS/m) increased seed germination percentage, while the high levels (5, 10, 15 and 20 dS/m) inhibited the seed germination significantly. The results showed that the effect of AgNPs was significant on germination percentage in P ≤ 0.05. Overall, application of AgNPs was beneficial in improving salinity tolerance in the Fenugreek seedling and its application may stimulate the differences defense mechanisms of plants against salt toxicity. 相似文献