جستجوی مقالات مرتبط با کلیدواژه « reproductive traits » در نشریات گروه « کشاورزی »

First lambing age and lambing interval are among the most important reproductive traits affecting profitability of sheep breeding systems. The present study aimed to conduct a genome wide association studies (GWAS) for identifying the loci associated with first lambing age and lambing interval in Zandi native sheep using the 50K arrays.

For this purpose, phenotypes records and genotypic data related to first lambing age and lambing interval were obtained from 96 Zandi sheep. Different steps of quality control and identification of independent SNP markers were performed by PLINK software. After quality control, 94 animals and 36070 markers were identified for further analysis. Genome wide association study was performed with reproductive traits using GEMMA software. Using the Genome Data Viewer software from NCBI database based on last assembly (ARS-UI_Ramb_v2.0) the SNP were assigned to genes if they were within the genomic sequence of the gene or within a flanking region of 300 kb up- and downstream of the gene. Finally, from online bioinformatics databases for the assignment of the genes to functional categories, DAVID and PANTHER databases were used.

In this research, seven SNP markers on chromosomes 1, 2, 3, 6, 11 and 23 were identified. Also, we identified different sets of candidate genes related to reproductive traits: UMPS, ITGB, SMARCAL1, APAF1, UGT8 and ST8SIA5 in Zandi sheep. Some of the found genes, are consistent with some of the previous studies related to reproductive traits. Some of the genes were found are consistent with some previous studies and to be involved biological pathways related to fertilization, ovulation rate, estrogen biosynthesis, conception rate, skeletal muscle development, early development of the fetus and puberty.

The results of our research can be used to understand the genetic mechanism controlling reproductive traits and considering, this study supported previous results from GWAS of reproductive traits, also revealed additional regions, using these findings could potentially be useful for genetic selection in sheep for age at first lambing.

The present research was conducted in order to achieve the best method of planting and obtaining the maximum yield of flowers and stigmas of saffron (Crocus sativus L.) in two stages in Sari Plain. The first stage was carried out in the research farm of Sari Agricultural Sciences and Natural Resources University during 2021-2022 as split plots on randomized complete blocks design with three replications, in which the experimental treatments included drainage depth (15, 30, and 45 cm) in the main plots and three drainage distances (50, 100 and 150 cm) in the subplots. In the second stage, the produced corms were stored for three months in the incubation environment, and then, the corms were transferred to two different environments of aeroponic and field to evaluate saffron's flower and stigma performance. The measured traits included the number of produced flowers, average flower weight, dry stigma weight in both field and aeroponic, and the amount of safranal, picrocrocin, and crocin and in aeroponic conditions. The evaluation of reproductive traits of saffron under aeroponic showed that with increasing the depth of the drain and decreasing the distance of the drain, traits such as the number of flowers, flower weight, and stigma dry weight increased; when the maximum value of these traits, equivalent to 4744 flowers.m-2, 1423 g.m-2, and 10.7 g.m-2 were observed at 30 cm drainage depth and 100 cm drainage distance, which did not have a significant difference with 45 cm drainage depth treatment and 100 cm drainage distance. In addition, the results showed that the amount of picrocrocin decreased with increasing the depth of the drain and the distance of the drain. In addition, no significant difference was observed between different treatments for crocin content. Comparing the reproductive traits of plants under two cultivation conditions, namely air, and field, revealed a reduction of 21%, 20%, and 12% in the number of flowers, fresh flower weight, and dry weight of stigma, respectively, within the field conditions. In summary, the findings suggest that, for optimal saffron production in coastal areas, the propagation of corms in the field at depths of 30 cm and 100 cm with proper drainage, followed by flowering of the propagated corms through aeroponic cultivation, could be a viable and economically sound approach for one-year saffron cultivation in the Sari plain region.

The economic benefit of dairy cattle breeding units is a function of milk production volume, reproductive efficiency and herd health that various environmental and physiological factors such as nutrition, parity and offspring sex can play a role in the incidence of these traits. the main aim of this study was to investigate the effect of calf sex on production, reproductive and udder health traits in Isfahan Holstein cows. The data included 37,038 Holstein cows from the first to fifth lactation period from 13 industrial herds during the years 2005 to 2017. To investigate the effect of calf sex on the production and health traits, the mixed linear model procedure and on the reproduction traits, GLIMMIX procedure of SAS9.4 software were used. The results showed that cows with female calf had higher 305-days of milk (90.7 kg) in compared to cows with male calf (P<0.01). For percentage of 305-d fat and protein and the number of days from calving to first service, the effect of calf sex different was low but significant (P<0.05). However, no significant difference was observed between male and female calves for other traits. According to the results, it seems necessary to consider the effect of calf sex in the genetic evaluation of Isfahan Holstein cows and also cost-benefit analysis of the use of sexed semen in herds.

Reproductive efficiency is one of the most important factors influencing dairy cow performance. In the present study, relationship between the polymorphism in interleukin 2 (IL-2: exon 6) and interleukin 10 (IL-10: exon 5) genes with reproductive characteristics including days open, calving interval, days from calving to first duty, gestation period, Service result, stillbirth and calving ease was examined.

In the present study, the relationship between interleukin 2 and interleukin-10 as two candidate genes with some important reproductive traits in Holstein dairy cows was investigated by means of selective genotyping. Individuals were selected based on their open door residuals obtained from mixed models. In the model used, the effects of year of birth, year of calving, time of calving and lactation were taken into account as fixed effects, and the random effects of the animal and the covariate effect of milk yield were also included in the model. A total of 194 cows, 97 of which were individual cows, were selected from both tails of the residual value distribution. The DNA was extracted using a modified salting out procedure. Polymerase chain reactions (PCR) using specific primers were implemented to amplify fragments of 172 bp and 325 bp of IL-2 and IL-10, respectively. Different banding patterns were identified using the PCR-SSCP technique. The Cox test in SAS was used to examine the association between banding patterns with open days, calving interval, days from calving to first service, gestation duration. The logistics regression was implemented in SAS for service results, stillbirths and calving ease.

The results showed the existence of polymorphism for both loci studied. Four different band patterns in IL-2 and seven different band patterns in IL-10 were observed. At the IL-10 locus, striped patterns 5 and 6 had the highest frequency and pattern 3 showed the lower frequency in the individuals with residual values below the mean. In the second group with residual values above the mean, the highest frequency was observed for pattern 6, which also had the highest frequency in the total samples. For IL-2, patterns 1 and 2 showed the greatest and lesser frequency, respectively, in the individuals with residual values below the mean. Pattern 4 had the lower frequency in this locus. Statistical results showed the significant association of IL-2 on open days and length of gestation. In addition, IL-10 had the significant effect on open days.

Taking into account the polymorphisms in the studied regions for the population of Holstein dairy cows and the association of these polymorphisms with reproductive traits, following confirmation of the results using sequencing approach, these regions could be considered in animal breeding programs.

Growth and reproductive traits are well-known characteristics of living organisms because of their direct relationship with economic benefits. Genetic description of the growth curve and the correlation of its parameters with growth and reproductive traits can be useful in determining selection strategies. For this purpose, 2035 quail data, which were collected during the years 1398-1396 in the Agricultural Research and Training Center and Natural Resources of Khorasan Razavi, were used. To identify the fixed factors affecting the traits, the linear model of GLM procedure of SAS software was used and to estimate the parameters of the growth curve, the nonlinear regression model of Gampertz was used. Genetic components variance (co) of growth curve and reproduction traits was estimated using maximum likelihood multi-trait analysis by DMU software. Heritability of body weight at 35 days (BW35), asymptotic weight (a), maturity rate (k), age at inflection point (IPT), absolute growth rate (AGR), relative growth rate (RGR), number of eggs (EN) and fertility percentage (FR) were estimated respectively 0.222, 0.238, 0.416, 0.283, 168 to be 0.22, 0.222, 0.283 and 0.071. Growth curve parameters with AGR and RGR and BW35 days had high genetic correlations (0.434 - 0.924). The strongest correlation was obtained between IPT and RGR (0.924). Except for genetic correlations between EN and FR percentage with other traits, most of the genetic correlations were positive. Based on this results, management of environmental factors are effective in increasing growth and reproductive performance, and genetic selection for growth trait using growth curve parameters can improve the genetic potential of the animals.

Inbreeding, which has been defined as the mating between relative animals, leads to increase homozygous genotypes and decrease heterozygous genotypes in a population. As a result, the progenies of such mating are inbred (Wakchaure and Genguly 2015). Reduction of the traits associated with physiological efficiency and reproductive potential are the most important impacts of inbreeding in the farm animals (Filho et al. 2015, Fleming et al. 2018). Traits in livestock have different heritabilities suggesting that they are not influenced by inbreeding in a similar pattern and that although animals’ fitness is generally deteriorated; the magnitude of inbreeding depends on the type of the trait (Roff 1998; Derose and Roff, 1999, Wright et al. 2008, Mikkelsen et al. 2010). Until now, all studies regarding effects of inbreeding on productive and reproductive traits of dairy cows have been focused on using the statistical models in which inbreeding coefficient was included as covariable (Behmaram et al. 2017) or as the classified variable (Amirzadeh 2012). As inbreeding coefficient is defined as a covariable in the model, only a regression coefficient is estimated describing average changes of the trait per increasing / decreasing inbreeding coefficient. As a matter of fact, inbreeding may unequally influence the shape of distribution of the trait. Based on this assumption, this research aimed to estimate inbreeding effects on some productive and reproductive traits of Iranian dairy cows using Quantile regression statistical method.     

The data set was provided by Animal Breeding Centre, Iran. Foxpro (version 2.6) and UEStudio (version 09) software were utilized for editing initial data. Final data consisted of 580,802 records belonging to 580,802 first-parity cows distributed in 1,185 herds (over 20 provinces of the country) and calved between years 1991 and 2015. The traits under consideration were lactation milk yield (TMILK), 305d, 2X milk yield (MILK3052X), average daily milk yield (ADM), lactation length (LL), and age at the first calving (AFC). The average of the traits in the final data set was 9,447 Kg, 7,792 Kg, 30 Kg, 315 d and 25.6 m, respectively. Holstein gene percentage (HGP) of the cows in the pedigree file was set to be in the range of 50 to 100 and AFC of the cows was set to be between 18 and 48 months. Inbreeding coefficient (IC) of individual animals was calculated by CFC software (Sargolzaei et al. 2006). Fitting a series of the Quantile regression models was conducted with the use of SAS (version 9.4) software. Quantile regression, which was introduced by Koenker and Bassett (1978), extends the regression model to conditional quantiles of the response variable, such as the 90th percentile. Quantile regression is particularly useful when the rate of change in the conditional Quantile, expressed by the regression coefficients, depends on the Quantile (Chen 2005). In all the models used in this research, fixed effects of province, year and month of calving, as well as linear co-variables of HGP, IC and AFC (except of the model for AFC as the trait) were included. For TMILK, lactation length was also included as linear co-variable. Moreover, in addition to the quantile models and for the sake of estimating usual regression coefficient, general linear model (GLM) was also fitted for each trait in which a single regression coefficient of the trait on IC was defined. Ordinary least-squares regression can be used to estimate conditional percentiles by making a distributional assumption such as normality for the error term in the model. The main advantage of Quantile regression over ordinary least-squares regression is its flexibility for modeling data with heterogeneous conditional distributions (Chen 2005).      

Based upon the analysis of main pedigree file, the total number of animals was 1,941,871 (16,169 sires and 895,376 dams) among which the number of base and non-base animals were 246,388 (3,936 sires and 120,287 dams) and 1,695483 (12,233 sires and 775,089 dams), respectively.Total number of inbred animals in the pedigree was 1,211,343. Average IC for total as well as inbred animals was found to be 0.9149% (minimum 0% and maximum 47.02%) and 1.4651% (minimum 0.00038% and maximum 47.02%), respectively. For the cows with records for all five traits, IC ranged from 0 to 38.45% with the average of 1.13% (SD=1.63%). Estimate of annual change of IC was found to be 0.017 (SE=0.005), which was statistically significant (P<0.01) indicating that there is a positive increase of inbreeding in Iranian dairy cows’ population over the time. Within each trait, different Quantiles were unequally influenced as animal’s IC increased. Vast majority of the estimated regression coefficients in different Quantiles were statistically significant (P<0.05). Based upon fitting Quantile regression model and the average estimated regression coefficients, it was found that TMILK, MILK3052X, ADM, LL, and AFC changed -5.5 (Kg), -2.6 (Kg), -18 (g), 0.35 (d) and 0.30 (d), respectively as the IC of the animal increased by 1%. Estimated simple regression coefficients based on fitting GLM models were found to be -9.83 Kg (SE=1.332 Kg), -6.9 Kg (SE=0.169 Kg), -32 gram (SE=4.2 gram), 0.2087 d (SE=0.08234 d) and 0.0158 m (SE=0.0024 m), respectively and all were statistically significant (P<0.05).     

This research indicated that different Quantiles of some productive and reproductive traits of Iranian dairy cows are not equally affected by inbreeding phenomenon suggesting that Quantile regression models are needed to be utilized in the future research for evaluating the impacts of inbreeding on the other traits, which are of great economic importance.

In the present study, data collected from 1993 to 2011 in Raeini Cashmere goat breeding station were used for genetic evaluation and inferring causal relationships among reproductive traits applying structural equation models. The studied lifetime reproductive traits were included the overall number of kids born (OLSB), the overall number of kids weaned (OLSW), the overall litter weight at birth (OLWB) and the overall litter weight at weaning (OLWW). Three models including standard (SMM), recursive based on prior knowledge (PRM) and recursive based on inductive causation algorithm (ICM) multivariate models were used for genetic evaluation of animals under the Bayesian approach. The comparisons of the investigated models via deviance information criterion (DIC), mean square error (MSE) and Pearson's correlations between observed and predicted records () revealed that ICM had lower DIC and MSE and higher () for all the studied lifetime reproductive traits; implying the more plausibility of ICM over SMM and PRM. Furthermore, re-raking of the animals under SMM and ICM confirmed the importance of considering the causal relationship among the traits for ensuring accurate ranking of animals according to their breeding values.

Background and objectives:

Some reports indicate that, due to different reasons, in grazing animals (such as nomad animals) nutrients deficiency may occur particularly for degradable and undegradable protein, metabolizable energy, vitamins and some minerals including sulfur and phosphorus. Thus, in some parts of the world, supplemental nutrients in the form of supplemental blocks are used in animal nutrition to overcome these deficiencies and to improve the nutritional value of consumed feeds. Application of supplemental blocks has been highly extended in recent years. The current study was designed and conducted to investigate the effects of supplemental block containing urea, molasses and mineral- vitamins on productive and reproductive performance of Qashqai ewes, in Fars province. Materials and methodsFor conducting the experiment, a total number of 75 Qashqai ewes (1-4 parity) were chosen and then distributed in a completely randomized design among 3 experimental groups (treatments) (25 replicates per treatment). All groups were fed with pasture forage as main feedstuff throughout the study. In the control group, ewes did not receive supplemental block but in two other groups, they received 100g (T100) or 150g (T150) block/ewe/day, in 2 phases (The first phase 20 days before breeding until 50 days after that and the second one 30 days before expected lambing until lamb weaning at 90 days of age). The supplemental block contained the following ingredients: molasses, urea, wheat bran, common salt, mineral-vitamin supplement, gypsum, cement and sodium bicarbonate.

Results :

The results indicated that feeding ewes with 100 or 150 g supplemental block resulted in a significant decrease in percentage of the barren ewes (P

Reproductive traits in sheep are the most important traits affecting profitability. These traits have categorical nature, but in practice the continuous distribution of traits is analyzed. In addition, to have true and accurate pedigree records, applying the appropriate model for analyzing the characteristics of high precision in the estimation of genetic parameters will be evaluated.Accurate prediction of animals breeding values is one of the best tools available to maximize the response to a selection program. Development of effective genetic evaluation and improvement programs requires knowledge of the genetic parameters for these economically important production traits. many studies, LS is analyzed by linear models, and the variance components are obtained by REML methods. Compared to linear models, non-linear models have disadvantages in goodness of fit or predictivty and they are time consuming in computation, which might be prohibitive for routine calculations The main objective of this study was to obtain effects of genetic estimates of reproductive traits in Makooei sheep using repeatability linear and threshold models that are necessary to develop an efficient selection strategy for improvement of reproduction. For this purpose, were estimated using linear and threshold univariate animal model on the data of 4319 records of 1629 ewes, collected during 1996 to 2014 in rearing and improvement of Makooei sheep for conception rate, number of lambs born, number of lambs alive at weaning, number of lambs born per ewe exposed and number of lambs born per ewe exposed traits. The model was included fixed effects (year and age of ewe) and random effects additive genetic of ewe, permanent environmental of ewe and residual. The overall mean of traits were as 0.93 for conception rate, 1.16 for number of lambs born, 0.98, for number of lambs alive at weaning, 1.07 for number of lambs born per ewe exposed and 0.91 for number of lambs born per ewe exposed. The heritability coefficient of traits were estimated as 0.05, 0.11, 0.06, 0.08, and 0.04 respectively, resulted from linear analysis and 0.12, 0.20, 0.15, 0.18 and 0.10 respectively, resulted from threshold analysis. The estimation of repeatability coefficient of traits were as 0.09, 0.16, 0.18, 0.15 and 0.12 respectively, for linear analysis and 0.48, 0.51, 0.34, 0.50 and 0.41 respectively for threshold analysis. The results of this study showed that, using threshold models for analyzing reproductive traits in genetic evaluations, comparison with linear models, caused relatively increasing genetic parameters and accuracy of evaluations.

Spontaneous barley is a category of cereal, annual plant, winter, self-pollinated, and diploid (2n=14). It has very close genetic relationship with barley. Very long awn, resistant to drought and salinity, seed dormancy and allelopathic potential are the features of this plant. The average 1000-seed weight without awn is 45grams and with awn is 47grams.Apart of the five provinces (Semnan, Golestan, Mazandaran, Guilan, Sistan and Baluchestan), the existence of this species was reported in Iran. The highest prevalence belongs to Fars province with an average density of 34 plants per square meter.Due to genetic and morphological similarities of spontaneous barley with wheat and barley, none of selective herbicide for wheat are able to control spontaneous barley.This study aimed to investigate the effects of the herbicide metsulfuron methyl + Sulfosulfuron (TOTAL) on morphological and reproductive characteristics of different ecotypes spontaneous barley and determine the best of use time these herbicides in the various growth stages of spontaneous barley. This experiment performed in Varamin region during 2013 and 2014 in form of Factorial randomized complete block design with four replications. The first factor included two levels of MetsulfuronMetyl+ Sulfosulfuron herbicide application at two leaf (GS =12) and second node (GS = 32) stages of growth spontaneous barley, and control without herbicide. The second factor was 20 ecotypes, which collected from across the country. At thirty days after the treatment which was equivalent to the heading stage of spontaneous barley, a box (0.5 × 0.5) was dropped on each line and then the morphology and reproductive traits of spontaneous barley were recorded. The greatest effect of TOTAL herbicide was at the time of the second node, but in two leaf also had a significant effect on reducing the density of spontaneous barley. Ecotypes Shush, Marvdasht, Urima, Shahreza, Islamabad, Isfahan, Golpayegan and Varamin after herbicide application at two stages were significantly more than control in term of plant density reduction. The use of herbicide reduced the number of stems per plant. Differences between treatments indicate that the effect of herbicides on stem growth has been positive. Totally, stems per plant reduction caused to reduction of the fruiting stems. This causes to reduce reproductive efficiency in spontaneous barley. In Ecotypes of Shush, Darab, Mahabad, and Biseton areas, effective of herbicides on leaf area index was higher at the two-leaf stage. Reduction of leaf area reduced the size and plant dry weight. TOTAL herbicide caused to weaken plants and plant density reduction by reducing the leaf area growth, and the growth of young stems. In Mahidasht, Fasa and Zarghan ecotypes, herbicide application at two leaves stage reduced the plant height more than second node stage. Using herbicides at second node stage,significantly changed the height of Salmas, Miandoab, Darab, Biseton, Shahryar, Golpayegan and shahreza ecotypes compared to control. Final height is one of the most important and effective indicator, in terms of weed-crop competition, which by light advantage, resulted to increasing the canopy, leaf area, dry weight and better competitive conditions. The use of herbicides at the two-leaf and the second node stages resulted incontrolling the final height of spontaneous barley compared to control. The plant fresh weight and dry weight of ecotypes showed a significant decrease as compared to the control. By reduction of spontaneous barley fresh weight, the reproductive ability reduced and also the canopy was decreased, which both have an important role on control of spontaneous barley. Moreover, according to another study among several tested herbicides in wheat, spontaneous barley did not lead to optimal control and only TOTAL decreased the dry weight by 67 percent. Using herbicides at second node stage resulted to reduction of spike weight in Shush, Fasa, Shiraz, Kerend and Varamin ecotypes than control. After herbicide application, due to unfavorable growing conditions and stress, the plant with minimal resources went to reproductive stage. Consequentlythe plants were weaker as compared to the control.Finally,the fertility rate reduced and spike length was shorter under the influence of herbicides. Using of herbicides at second node, most of the ecotypes showed seed weight reduction. The results showed that the use of TOTAL herbicide at the two-leaf stage and the second node decreased morphological and reproductive characteristics of this weed. The biggest influence on morphological characteristics of the Bistoon ecotype (density), Shiraz ecotype (plant density, leaf area, fresh weight, Dry weight, spike length), Rāmhormoz ecotype (number of stems, plant fresh weight, Dry weight), Mahidasht ecotype (LAI), Fasa ecotype (height, leaf area index, fresh weight, dry weight, grain weight, spike weight), Golpayegan ecotype (final height), Branch ecotype (final height), Shush ecotype (number of stems, number of grains per spike), Marvdasht ecotypes (seed weight, weight spike), Zarghan ecotype (spike length). Ecotypes reactions to the herbicide suggested that potential genetic differences among ecotypes creates different conditions of increasing or decreasing of the studied traits. Knowing these differences guide us to control this weed at different stages of plant growth by suitable approaches.

This research was done to estimate of inbreeding coefficient and its effect on some of productive and reproductive traits in Moghan agro-industrial company Holstein cows with using of 17966 Holstein cows pedigree data from 2007 to 2016. For preparing and editing of data, estimate of inbreeding coefficient and traits regression content from inbreeding Fox pro, Excel, CFC and Wombat softwares were used respectively. 32.12 percent of total animals were inbreed. Inbreeding coefficient average for total population and inbreed animals in this study was calculated 0.56% and 1.85% respectively. The lowest and highest inbreeding amount in this herd was observed 0.78% and 37.5% respectively. Inbreeding depression for 1% increasing of inbreeding for milk production, number of days in milk, open days and age at first calving were estimated -15.14 kg, -1.60, 0.09 and 0.40 day respectively, except for age at first calving was not statistically significant (P>0.01). The results of this research showed, in compare with the other similar population, average of inbreeding coefficient was lower in this herd that could be related to factors like preventing of very close inbreeding and tending to controlled mating.

Genetic improvement in reproductive and growth traits is major goal in sheep breeding. In this study, we performed a genome wide association study for detection of quantitative trait loci affecting reproductive traits in Baluchi sheep. For this purpose, blood samples were collected from a total of 96 ewes and data on their reproductive traits including total litter weight at birth (TLWB), litter mean weight per lamb born (LMWLB), total litter weight at weaning (TLWW), litter mean weight of lambs at weaned (LMWLW) and number of lambs alive at six months (NLA6m) in four parity. After DNA extraction, samples were genotyped using the Illumina Ovine SNP 50K BeadChip assay. Using PLINK software, a GWA study was performed in linear (GLM) and logistic regression analyses with a model included SNPs effect and sex and number of parities as fixed effects. A total of eight SNPs were found on chromosomes 1, 4, 10, 15 and 17 at the 5% chromosome-wise significance level (P

In the current study, two groups of lines Coturnix Japonica Quail that were selected for hig (HW) and low (LW) body weight at the age of 4 weeks for 7 generations were used. HW line after selection for 7 generations was significantly heavier than LW line in the same generation at the age of 28days (p

Root-knot nematodes (Meloidogyne spp.) are the limiting factors of agriculture crops including pepper. The M. incognita has widely distributed in pepper fields of Gilan Province. In this study, eleven pepper cultivars including AA pepper (Hyb. Coyame- Petoseed, Hyb. Aziz- Petoseed, Hyb. Bounty- Petoseed) and Bell peppers (California Wonder 301- Petoseed, Hyb. Camelot- Petoseed, Hyb. King Arthur- Petoseed, Hyb. Wizard- Petoseed, Hyb. Aristotle (SQ-R)- Petoseed, Hyb. Plato (SQ-R)- Petoseed, Mercury- Petoseed, California Wonder 301- Canyon) were evaluated against M. incognita race 2. Experiments conducted in a completely randomized design with four replications in greenhouse conditions with range of 22 to 28 Celsius degrees. Seedlings with six leaves were inoculated with 2000 second-stage juveniles/kg soils. Eight weeks after inoculation, growth indexes cultivars (Chlorophyll content of leaves, fresh and dry weight of shoot and root, root length and volume, length and diameter of shoot and number of healthy leaves) and nematode reproductive traits (Number of galls, egg masses, juveniles in the soil and nematode reproduction factor) were evaluated. In the final reaction of cultivars were determined based on reproduction factor gall and egg masses and resistance indices. The results revealed that pepper cultivars showed different ranges of sensitivity to the nematode. Based on the growth factors, hybrid wizard, California Wonder 301, Bavnty Hybrid, Mercury and Camelot hybrid cultivars were less sensitive than others cultivars. Among cultivars, California Wonder 301, Bavnty Hybrid, Mercury and Camelot hybrid showed less sensitivity in reproductive. The assessment of gall, egg masses and resistance indices revealed that Mercury and Camelot hybrid were evaluated as tolerant cultivars and King Arthur's hybrid and aziz hybrids as the most sensitive cultivars.

The application and environmental hazards of nanotechnology to aquatic species are increasingly growing. To address the issue, the present study was designed and carried out to elucidate the toxic effects of silver nanoparticles on growth, survival and reproductive traits of Artemia urmiana. The experiment consisted of five treatments, namely control group and those exposed to 0.001, 0.01, 0.1 and 1 mgl-1 silver nanoparticles, with four respective replicates. To do so, 500 newly hatched nauplii were counted and transferred to 1 liter containers exposing to various concentrations of the silver nanoparticles . Microalgae Dunaliella tertiolecta and zymogenic was used to feed artemia. Growth and survival rates were recorded on days 8, 11, 17, 20 and 23. After sexual maturation, artemia were transferred to a new environment free from nanoparticles and their reproductive traits were studied. Results showed that higher concentrations of silver nanoparticles led to lower survival rate and augmented growth rate of artemia (p