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Salinity is considered as the main factor limiting the yield of crops in arid and semi-arid regions. There are still many uncertainties about the nanotechnology and its potential applications, as well as doubts about its efficacy and safety in the long term. The aim of this study was to examine the alleviative effects of ZnO NPs (nanoparticles) (0, 20 and 80 mgL?1) on toxicity damage caused by NaCl (0, 50 and 100 mM) at physiological and molecular parameters in Rapeseed. Rapeseed plants were treated at the rosette stage by different levels of salinity and ZnO NPs based on a completely randomized design (CRD) with three replications. At the physiological level, salinity stress significantly increased root ion leakage and decreased relative water content (RWC), stomata density and Hill reaction while application of ZnO NPs improved Hill reaction, and reduced ion leakage. At the molecular level, salinity stress significantly reduced the expression of ARP, MYC and SKRD2 genes compared to non-stressed plants while MPK4 gene expression increased under a high level of NaCl imposition. Foliar spraying of ZnO NPs considerably decreased the expression of MYC, MPK4, and SKRD2 genes and increased the expression of the ARP gene. It can be concluded that ZnO NPs had the ability to reduce the toxicity created under salinity stress at the optimal concentration (20 mgL?1) in rapeseed and could play an important role in increasing the resistance of rapeseed plants to salinity stress.  相似文献   
2.
The primary goal of this project was to establish a protocol to freeze the sperm of the Caspian miniature horse in an attempt to start an intensive artificial insemination program to effectively increase the population of this breed, which has been listed as “Critical Rare Breed” by the American Livestock Breed Conservancy and is in danger of extinction. Commercially available equine freezing medium (EquiPRO CyoGuard Complete egg-yolk extender) was used for the initial setup of two different freeze protocols: slow and fast. The fast-freeze protocol had slightly better postthaw results and was used for a fertility demonstration. Five mares of proven fertility, aged 3 to 12 years, were used in the fertility trials, two of which resulted in pregnancy. This is the first report of pregnancy in the Caspian miniature horse using frozen semen, and the results seem to be a promising start to an extensive program to help this endangered breed, although further research on freezing protocols and conditions for this process are necessary to further improve the survival of semen and pregnancy rate.  相似文献   
3.
To evaluate the impact of nano-iron oxide and zinc sulfate fertilizers on peppermint in field conditions, a factorial split experiment with two micro-nutrient fertilizers [Zinc (Zn) and Iron (Fe)] in RCBD with three replicates was conducted at University of Tehran, during 2014 and 2015. Fe at four levels (0, 0.25, 0.5, and 0.75 g L-1) and Zn at three levels (0, 2.5, and 5 g L-1) were applied. Fe and Zn fertilizer application significantly improved photosynthetic pigments, mineral nutrient content, essential oil concentration, and dry matter yield in peppermint. The highest iron content (1578.00 mg kg?1) was achieved when 5 g L?1 of Zn was applied along with 0.75 g L?1 Fe. According to our results, the application of 2.5 g L?1 of Zn plus 0.5 g L?1 Fe fertilizers could be recommended to achieve the highest plant dry matter and essential oil yield.  相似文献   
4.
Our objective was to study the relationships between colostral somatic cell counts (SCC, a criterion for mastitis severity at parturition) and early calf growth, blood indicators of immunity, and pre‐weaning faecal and health states. Sixty‐nine Holstein cows were assigned to three groups of greater (n = 21, 5051 × 103), medium (n = 38, 2138 × 103) and lower (n = 10, 960 × 103) colostral SCC (per ml) in a completely randomized design. Calves received 2 l of colostrum on day 1, and jugular blood was sampled at birth, at 3 h after the first colostrum feeding and at 42 days of age for immunoglobulin G (IgG) measurements. Calves were fed transition milk from their dams until 3 days of age and whole milk from 4 to 60 days of age twice daily at 10% of body weight. Health status and faecal physical scores were recorded daily for 42 days. Increased colostral SCC was associated with increased serum IgG at parturition. Colostral pH increased and fat percentage decreased linearly with the rising SCC. Feeding colostrum with greater SCC was associated with reduced serum IgG concentrations at 3 h after first colostrum feeding, greater incidences of diarrhoea and compromised health status during the first 42 days of age, and reduced weaning weight gain, but had no effects on calf body length and withers height. Colostral volume and percentages of protein, lactose, solids‐non‐fat, total solids and IgG were comparable among groups. Results suggest a role for SCC, as an indicator of mastitis and colostral health quality, in affecting calf health. As a result of the novelty of calf health dependence on colostral SCC found, future studies to further characterize such relationships and to uncover or rule out possible mediators are required before colostral SCC could be recommended for routine on‐farm use in managing dry cow and calf production.  相似文献   
5.
Potato tuber worm, Phothorimae operculella Zeller (Lepidoptera: Gelechiidae) is a common pest of potato which causes a heavy loss in yield either in fields or storage. The effect of six potato cultivars (Agria, Florida, Impala, Picasso, Satina, and Sprint) were evaluated on the life history, life table and demographic parameters of P.operculella under laboratory conditions, which could be appropriate indices in resistance and susceptibility evaluation of potato cultivars. The longest development time was on Picasso (28.76 ± 0.36d) cultivar. The male longevity ranged from 4.83 ± 0.44d on Sprint to 7.45 ± 0.60d on Picasso. Impala and Satina with 53.22 ± 7.78 and 28.74 ± 3.54 eggs/individual had the highest and the lowest net reproductive rates (R0). The highest values for the intrinsic rate of increase (rm) and finite rate of increase (λ) were on Impala (rm: 0.119 day?1, λ: 1.75 day?1), and the lowest value was on Sprint (rm: 0.090 day?1, λ: 1.01 day?1). The results indicated that Sprint was the most resistant cultivar for the feeding of P.operculella, which could be useful in the development of integrated pest management programs for this pest.  相似文献   
6.

Shortage of winter chill has reduced pistachio (Pistacia vera L.) fruit yield and quality from 2015 to 2018 in Iran. In this study accumulated chilling was determined by the chill hour (CH) and the dynamic (DM) model in five regions near Shahrebabak County, Kerman Province, Iran, for dormant season 2017–2018. The CH model has been routinely used in Iran for reporting chilling accumulation for pistachios. This study suggested that the DM better differentiated regional chill accumulations, the impact of chilling on phenological indices of growth and production between cultivars ‘Owhadi’ and ‘Akbari’, with and without rest-breaking (RB) treatments of Volk dormant oil. Volk oil treatment significantly improved vegetative and reproductive development, offset lack of chilling effects on pollination and nut filling, and may have advanced budbreak in some instances.

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