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21.
Abstract

Among major constraints to crop production, salt stress affects the morphological structure and yield in crop plants. Nano-fertilizers, have made their hierarchy to supplement the traditional fertilizers in mitigating the effect of abiotic stress due to their slow release and efficiency. Three products were tested namely lithovit®-standard(LITHO), monopotassium-phosphate(MKP:0-52-34), and aspirin(ASP) on salt-stressed tomato crop. These products were applied through foliar spraying (foliar) or fertigation (ferti) on tomato plants irrigated with 4 saline solutions (4, 6, 8 and 10dS/m). Control plants were subjected to five salinity levels (0, 4, 6, 8 and 10dS/m) without any treatments. Results showed that increasing in salinity levels adversely affected all parameters in the control plants. The ameliorating effect of MKP-ferti was prominent in plant height, stem diameter, number of fruits, fruit weight and yield/plant at 4 and 6S/m. Whereas, the effect of salinity was mitigated by LITHO-foliar regarding flowers number and total chlorophyll content at all salinity level. Leaf N, P and K contents were accumulated higher when MKP-ferti was used whereas, Ca2+ and Mg2+ contents were accumulated higher in the plants treated with LITHO-foliar. The cellular leakage of electrolyte was reduced at 4, 6 and 10dS/m with MKP-ferti and at 8dS/m with LITHO-foliar application. Among the two methods of application, foliar spraying of LITHO and ASP, and fertigation of MKP improved plant performance more than their complementary methods of application. The better performance of MKP necessitates the use of phosphorous and potassium-based nano-fertilizers. It can reduce the production cost of vegetables using conventional fertilizers.  相似文献   
22.
Background:Bovine papillomatosis (BP) is considered the most common health problem in large cattle farms.Aim:This study attempts to confirm clinically suspected BP in cattle by polymerase chain reaction (PCR) assay, histopathology, immunohistochemistry (IHC), and genotyping analysis of local isolates.Methods:According to morphological appearance and lesion features, a cross sectional study of 54 clinically diagnosed BP cattle was assigned to this current investigation from May to August (2021) in Al-Kut district (Wasit Province, Iraq) private veterinary clinics using purposive sampling technique based on set criteria. The cattle were diagnosed clinically, and the tissues were collected and some fixed in 10% neutral buffered formalin and other stored frozen and examined by histopathological technique, IHC, and PCR assays.Results:Using PCR assay, all cattle were positive for the BPV L1 gene. According to detect the L1 gene, analysis of the phylogenetic tree showed that local BPV cattle isolates were closely related to the NCBI-BLAST BPV type-1 and type-2 of the Polish equine isolate (KF284133.1) and BPV Brazilian Bostaurus isolate (MH187961.1), respectively. Histological detection showed there were acanthosis, hyperkeratosis, epidermal thickening, severe infiltration of mononuclear cells, massive hemorrhage, dermal fibroplasias, multifocal spongiosis, moderate neovascularization, moderate to severe elongation of the retention ridge towards the dermis, parakeratosis, rings of calcification, and necrosis with nuclear pyknosis of some spinosum cells. Immunohistochemical findings of tumor necrosis factor-alpha, epidermal growth factor receptor and Fascin showed a significant variation in values of immunoreaction in the dermis and epidermis. These results ranged from negative (0) to mild positive (+1) to moderate positive (+2) reactions.Conclusion:The study provided essential molecular and genotyping data to improve our knowledge by emphasizing the crucial of IHC as an elegant diagnostic method to detect cellular alterations.  相似文献   
23.
Potato (Solanum tuberosum) is one of the important vegetable crops in the world and its production is seriously affected by apical leaf curl disease in northern India. This paper reveals the role of cucurbits in maintaining Tomato leaf curl New Delhi virus (ToLCNDV) and Potato apical leaf curl (PALCD) disease in that region. The affected plants showed severe leaf curling and stunted growth. The begomovirus causing leaf curling and mosaic disease in cucurbits could be easily transmitted by the whitefly to potato crops and develop apical leaf curl disease in northern India. The movement of the virus by whiteflies from cucurbits to potato and tomato is possible because of overlapping of planting and harvesting dates of these crops. The causal virus was identified as a begomovirus on the basis of whitefly transmission, PCR, dot blot hybridization, cloning and sequencing of the coat protein gene. The comparison of full length coat protein gene sequence homology revealed that 90% identity with the coat protein gene of ToLCNDV- [Luffa] isolate and the phylogenetic tree derived from these sequences with other selected begomoviruses formed a close cluster with ToLCNDV isolates. The findings proved that the virus causing disease in cucurbits could easily move to tomato and potato and cause leaf curl disease naturally. This is the first observation on the role of sponge gourd for maintenance of ToLCNDV and serving as a host for PALCD in northern India. The findings indicate that the causal organism is a strain of ToLCNDV.  相似文献   
24.
5种引诱剂田间诱捕苹果蠹蛾效果比较   总被引:1,自引:0,他引:1  
利用5种引诱剂对苹果蠹蛾在乌鲁木齐地区的消长动态进行监测。结果发现,苹果蠹蛾在乌鲁木齐地区1 a发生2代,还有一个不完整的第3代。对比进口型、聚集+性诱型、普通型、聚集型、加强型5种引诱剂的田间引诱效果,加强型引诱剂最好,整个监测期间,每个诱捕器诱捕到的雄虫总数平均为163.7头,单日最高引诱量达育每只30头;进口型引诱剂效果最差。从粘虫板和诱芯的更换周期等对引诱效果的影响来看,每10 d更换1次粘虫胶的诱捕效果好于30 d更换1次,但诱芯更换周期对引诱效果影响并不明显。  相似文献   
25.
Rice, a staple cereal crop in many parts of the world, has been confronted with multiple environmental stresses including high temperature, negatively impacts the booting as well as anthesis growth stages. The situation is further complicated by the changing climatic conditions, resulting in gradual escalation of temperature as well as changing the rainfall pattern and frequency, thus raising a concern of food security worldwide. The situation can be combat by developing rice varieties with excellent genetics with improved morpho-physiological, biochemical, and molecular mechanisms, together can minimize the adverse effects of heat stress. Here, several strategies (encompassing genetic and genomic, and mechanisms involved) for mitigating the impact of high temperature on rice have been discussed. Finally, the utilization of genomic knowledge in augmenting the conventional breeding approaches have been comprehensively elaborated to develop heat tolerant germplasm.  相似文献   
26.
Thirty-two Nili-Ravi buffaloes were used to determine the effect of prepartum immunopotentiation in late gestation with levamisole hydrochloride (0.5 mg/kg), vitamin E+selenium (vitE-Se) (Etosol-SE, 10 ml intramuscularly) or Bacille Calmette Guerin (BCG) (0.5 ml/animal, subcutaneously) on postpartum reproductive performance. The immunopotentiating treatment was given twice, with treatments one week apart, approximately 80 days prior to the expected date of parturition. Prepartum treatment with vitE-Se or BCG significantly (p<0.05) reduced the calving to first oestrus interval and the length of the postpartum service period compared to the control group. The uterine involution period was significantly shorter in buffaloes treated with vitE-Se compared to the control group. Levamisole hydrochloride apparently improved the reproductive performance, but this result was not statistically significant.  相似文献   
27.
[目的]评价地衣重金属富集能力及其在城市空气环境质量评价中的应用前景.[方法]利用地衣移植法把丽石黄衣移植到乌鲁木齐市区15个监测点,用原子吸收光谱仪测量地衣体内6种重金属含量,根据重金属含量计算单项污染量指数和Nemerow综合污染指数.[结果]随着移植时间的延长地衣体内的重金属含量出现上升趋势,丽石黄衣体内重金属含量具有显著的时空变化特征.同时把单向污染量指数作为变量进行聚类分析和主成分分析,显示15个监测点分为轻污染区、中度污染区、重污染区,严重污染区等三个等级.[结论]地衣具有较高的重金属富集能力,对大气污染较敏感,可以作为大气环境质量评价指示地衣种类.  相似文献   
28.
Instillation of parainfluenza virus type 2 in the mammary gland of the goat resulted in the appearance of specific and high titered antibodies in the milk. The globulin fraction of the milk was separated and conjugated with fluorescein isothiocyanate. These conjugated antibodies could be successfully used in the specific staining of the homologous virus in infected L-132 cells. Therefore, milk from such immunized animals represents a rich and convenient source of specific antibodies for use in immunofluorescence and other serological tests.  相似文献   
29.
This study was designed to evaluate the relative toxicity of (+)- and (-)-gossypol enantiomers in 0-3-week-old broilers. Treatments consisted of broiler starter diets formulated with either a glandless, which did not contain gossypol, a commercial glanded [62. 2% (+)-gossypol], or a glanded moco [83.2% (+)-gossypol] crushed cottonseed (CCS) (six replicates/treatment) plus a soybean meal negative control. Glandless cottonseed was mixed with the moco cottonseed (2.4% free gossypol) so that both the commercial glanded and moco glanded cottonseeds contained equivalent concentrations of free gossypol (2.0%). The cottonseed treatments were added at 5 and 10% of the diet. Body weights and feed conversions were determined weekly. Body weights and feed-to-gain ratios of broilers fed 5 and 10% glandless CCS and 5% moco CCS were not significantly different. Broilers receiving 10% commercial glanded CCS weighed significantly less than those subjected to all other treatments. Feed-to-gain ratios were significantly higher for broilers receiving 10% commercial glanded and 10% moco CCS as compared to 5% moco and glandless CCS, 10% glandless CCS, and control. Relative liver weights of birds receiving 10% moco CCS were significantly less than those of birds receiving 10% commercial CCS. The data clearly showed that broilers fed moco CCS containing a relatively high (+)- to (-)-gossypol enantiomer ratio performed better than broilers receiving commercial CCS with a lower (+)- to (-)-gossypol enantiomer ratio.  相似文献   
30.
Improving water use efficiency in rice irrigation through wet-seeding   总被引:1,自引:0,他引:1  
Since the early-1960's, when modern rice production technologies became available, more than 90% of the total irrigation water developed in south and southeast Asia is used for rice culture. But currently rice culture is highly inefficient in water use. As fresh water availability for agriculuture is becoming increasingly scarce, greater efficiency of water use in rice culture is deemed essential. Past experience indicates that effective implementation of water-efficient irrigation methods in rice farms within public sector irrigation systems is restricted by the difficulty of controlling water deliveries and distribution, and establishing a water charge system based on the actual amount of water used by farmers. Clearly, a rice production method that is inherently less water-requiring, or more water-efficient, would have an advantage over the traditional method in this respect. Recent studies conducted in the Philippines indicate that wet-seeded rice culture is superior to the traditional transplanted rice culture in terms of water efficiency. Other advantages of wet-seeded rice culture include its greater drought tolerance, less labor requirement for crop establishment and weed control, and higher returns from rice farming. This paper presents a comparative study of wet-seeded and transplanted rice cultures focusing on these aspects.  相似文献   
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