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1.
Microinjection of exogenous DNA into the cytoplasm of matured oocytes or zygotes is a promising technique to generate transgenic animals. However, the data about the microinjection time and procedure in sheep are limited and have not treated in detail. To obtain more in-depth information, the Sarda sheep oocytes from abattoir-derived ovaries were subjected to IVM and IVF. Then, the GFP plasmid as a reporter gene was injected into the cytoplasm of MII oocytes (n: 95) and zygotes at different post-insemination intervals (6–8 hpi, n: 120; 8–10 hpi, n: 122; 10–12 hpi, n: 110 and 12–14 hpi, n: 96). There were no significant differences in the cleavage rates between the groups. However, blastocyst rate of injected zygotes at all-time intervals was significantly lower than injected MII oocytes and control group (< 0.05). Interestingly, the proportion of GFP-positive embryos was higher at 8–10 hpi compared with other injected groups (4 % versus 0 %, < 0.01). Among these, the proportion of mosaic embryos was high and two of those embryos developed to the blastocyst stage. In conclusion, we settled on the cytoplasmic microinjection of GFP plasmid at 8–10 hpi as an optimized time point for the production of transgenic sheep and subsequent experiments.  相似文献   
2.
Understanding farmers’ decision process on the adoption of biological control (BC) may help in promoting adoption. This study explored for the first time the impact of marketing mix elements (product, price, promotion, and place) on bolstering BC for the management of rice stem borer (Chilo suppressalis Walker) among rice farmers in Fuman County in northern Iran. Farmers using BC were familiar with this method primarily via village councils and rural municipality organizations (Dehyaris) and then via distributors of trichocards. Almost half of the farmers (48.3%) had weak to moderate level of contact with distributors of trichocards. All four elements (4Ps) of marketing mix (product, place, price, and promotion) were effective on the marketing of BC agents. Place (distribution) mix, followed by price mix, were the most important factors in marketing trichocards in farmers’ views. According to the sensitivity to 4Ps of marketing mix, most farmers were grouped as semi-sensitive (45.6%) and sensitive (39.4%). Overall, the availability of biological agent products in the market, the affordable price of the products, and the strong relationship of rural people with village councils and rural municipality organizations (Dehyaris) are crucial factors for BC promotion in paddy fields of Fuman.  相似文献   
3.
The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds.  相似文献   
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Genetic Resources and Crop Evolution - Salinity is one of the well-known abiotic stresses resulting in loss of wheat yield. The identification of differentially induced genes and then becoming...  相似文献   
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In no-tillage (NT) system, precedent crop residue retains on the soil surface to preserve soil water for crop growth. In response to the negative impact of soil degradation under conventional tillage (CT) system based on soil tillage, NT system without tillage practice and with protective cover of crop residue is being developed in many parts of the world. However, NT is a successful system especially in the South of America, but the impacts of this system on the Mediterranean climate especially in the southeast (SE) of France is less known; therefore, this study has been carried out within the scope of a European project. Durum wheat and corn were sown under CT and NT. Time requirement and fuel consumption in these two systems were measured. The results showed that durum wheat and corn yields were the same in both systems except of 2008, while work duration and energy requirement were 87% and 83% lower in NT system, respectively. Furthermore, NT could mitigate CO2 emission up to 50% as compared with CT. These results show that NT can be considered as a relevant alternative for CT regarding economical and environmental advantages.  相似文献   
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Crop breeders often have to consider multiple traits for selecting and advancing superior genotypes. Under such circumstances, use of selection indices is considered superior to other selection approaches, such as tandem selection and independent culling. While many types of selection indices have been developed (e.g., Smith and Hazel index, Desired gain index, Brim index, and Robinson index), programs for computing some of them (e.g., Desired gain index, Brim index, and Robinson index) are not available. We have developed a comprehensive SAS (Statistical Analysis System) code to compute the following indices: Smith and Hazel index, Desired gain index, Brim index, and Robinson index. The program also computes efficiency and genetic gain associated with these indices. The computer program reported here is named Shiri-SAS-Index-Selection, which is simple and easy to use. We present examples of SAS output generated by the Shiri-SAS-Index-Selection program for two breeding strategies. The program can be accessed here.  相似文献   
9.
Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (W12), average daily gain from birth to 6 months old (ADG6), and Kleiber ratio at 6 months (KL6) traits using 6,442 records obtained from a Raini Cashmere goat flock. The parameters were estimated using the restricted maximum likelihood procedure and applying four animal models excluding or including maternal additive genetic and permanent environmental effects. Heritability estimates for W6, W9, W12, ADG6, and KL6, under the most appropriate model were 0.028, 0.26, 0.29, 0.02, and 0.25, respectively. The estimates of genetic and phenotypic correlations among W6, W9, W12, and ADG6 were high and ranged from 0.73 to 0.99. The estimates of genetic and phenotypic correlations among KL6 and others traits were negative and low. Thus, these estimates of genetic parameters may provide a basis for deriving selection indices for postweaning growth traits also low genetic correlation between growth traits with KL6, it is possible to increase efficiency in Raini kids by multitrait selection.  相似文献   
10.
Data and pedigree information used in the present study were 3,022 records of kids obtained from the breeding station of Raini goat. The studied traits were birth weight (BW), weaning weight (WW), average daily gain from birth to weaning (ADG) and Kleiber ratio at weaning (KR). The model included the fixed effects of sex of kid, type of birth, age of dam, year of birth, month of birth, and age of kid (days) as covariate that had significant effects, and random effects direct additive genetic, maternal additive genetic, maternal permanent environmental effects and residual. (Co) variance components were estimated using univariate and multivariate analysis by WOMBAT software applying four animal models including and ignoring maternal effects. Likelihood ratio test used to determine the most appropriate models. Heritability ( \texth\texta2 ) \left( {{\text{h}}_{\text{a}}^2} \right) estimates for BW, WW, ADG, and KR according to suitable model were 0.12 ± 0.05, 0.08 ± 0.06, 0.10 ± 0.06, and 0.06 ± 0.05, respectively. Estimates of the proportion of maternal permanent environmental effect to phenotypic variance (c 2) were 0.17 ± 0.03, 0.07 ± 0.03, and 0.07 ± 0.03 for BW, WW, and ADG, respectively. Genetic correlations among traits were positive and ranged from 0.53 (BW-ADG) to 1.00 (WW-ADG, WW-KR, and ADG-KR). The maternal permanent environmental correlations between BW-WW, BW-ADG, and WW-ADG were 0.54, 0.48, and 0.99, respectively. Results indicated that maternal effects, especially maternal permanent environmental effects are an important source of variation in pre-weaning growth trait and ignoring those in the model redound incorrect genetic evaluation of kids.  相似文献   
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