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M. Angeles Achon Vicente Medina Michael Shanks Peter Markham George P. Lomonossoff 《European journal of plant pathology / European Foundation for Plant Pathology》1994,100(2):157-165
In order to characterise and classify an unknown maize-infecting potyvirus isolated from fields in northeast Spain, the entire coat protein gene and the C-terminal twothirds of the large nuclear inclusion protein (NIb) gene were cloned and sequenced. Protein sequencing enabled the cleavage site between the two proteins to be deduced and also revealed that on storage the viral coat protein undergoes a specific degradation in which the N-terminal 39 amino acids are removed. Comparison of the nucleotide sequence of the 3 non-coding region of the viral RNA and the predicted amino acid sequence of the coat protein with the equivalent regions of other members of the potyvirus group revealed that the Spanish virus is closely related to maize dwarf mosaic virus strain A. 相似文献
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Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season
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The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p < .05) and monocytes (2.93 ± 0.13; p < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer. 相似文献
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Effects of spent mushroom substrates and inorganic fertilizer on the characteristics of a calcareous clayey‐loam soil and lettuce production
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![点击此处可从《Soil Use and Management》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We evaluated the effects of the addition of two types of spent mushroom substrate (SMS), SMS from an Agaricus bisporus crop (SMS1) and a mixture of SMSs from an A. bisporus crop and a Pleurotus crop (50% v/v each) (SMS2), on the characteristics of a calcareous clayey‐loam soil and the yield and nutritional status of lettuce (Lactuca sativa L.), relative to crops receiving mineral fertilizer (M) and a control (C) without amendment. The application of SMS, especially SMS1, improved soil fertility compared with C and M soils. Moreover, the use of these organic substrates as soil amendments did not harm the plants and gave yields similar to that obtained with mineral fertilizer. The nutritional contents of the lettuce plants were greater than or similar to those of the plants from treatment C or M, except for the plant tissue concentrations of K, Fe and Zn, which were significantly reduced by SMS application. However, this latter fact did not reduce the lettuce yield in the amended soils. Therefore, the use of SMSs as organic amendments contributes to residue utilization, in an environmentally friendly way, and to improved soil fertility and crop yield. 相似文献
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不同欧李品种(系)光合与水分利用特性比较 总被引:1,自引:0,他引:1
以9种不同欧李品种(系)为试材,使用GFS3000光合测定系统测定了自然条件下叶片的光合和水分利用特性。结果表明:9种欧李品种(系)的净光合速率(Pn)、叶片气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)、蒸腾比率(TR)、水分利用效率(WUE)均存在差异;在新疆生产建设兵团第十四师二二四团的生长环境下,Pn与Gs、Tr、WUE呈极显著正相关关系,而与Ci、TR呈极显著负相关关系;Ci与TR呈极显著正相关相关关系,与WUE呈极显著负相关关系;Gs与Tr呈极显著正相关关系,与TR呈显著负相关关系;Pn最高的"宏宇Ⅵ号"其WUE较高,但不是最高;WUE最高的"宏宇Ⅰ号"其Pn较高,但不是最高;"01-01号"的Pn和WUE均最低,其它品种(系)的Pn和WUE均处于中等水平,不同的欧李品种(系)通过不同方式协调自身的光合和水分利用来适应生长的环境。 相似文献
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基于北京大兴区耕地质量等级调查评价成果,按《土地质量地球化学评价规范》(DZ/T 0295—2016)补充采样调查测试,开展研究区特色农业产区土地质量地球化学评价.结果表明,研究区特色农业产区土壤养分综合等级主要以二等为主,面积为10266.18hm2,占特色农业产区总面积的53.67%;土壤环境质量总体优良,土地质量状况整体良好.特色农业产区土地质量地球化学评价结果可揭示特色农业产地土地质量等级以及重要土地问题,为区域特色农产品与生态农业开发等提供依据. 相似文献
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玉米多胞质雄性不育杂交种冀玉988的选育及利用 总被引:2,自引:0,他引:2
不育化制种主要在于保证杂交种子的质量及降低其生产成本。多胞质杂交种的利用主要拓宽胞质异质性,增强杂交种对环境的适应能力与防范小斑病菌新的专化小种的严重为害。本研究以优良玉米新品种冀玉988(6048×黄选921.6)为背景,以s组的s,M,R与21A及C组的Rb,Bb与Es雄性不育细胞质(CMS)为试材,将母本6048转育成同核异质体,不育性稳定。父本921.6对21A,s与R三种CMS具有强恢复性。本研究论证了多胞质杂交种在生产上利用的可行性。冀玉988已配制成具有恢复性能的多胞质雄性不育杂交种,可用于生产。 相似文献
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David Santiago‐Ramos Juan de Dios Figueroa‐Crdenas Jos Juan Vles‐Medina Rosalía Reynoso‐Camacho Minerva Ramos‐Gmez Marcela Gaytn‐Martínez Eduardo Morales‐Snchez 《Cereal Chemistry》2015,92(5):475-480
The objective of the present work was to study the effect of annealing and concentration of Ca(OH)2 (lime) and calcium salts on the thermal and rheological properties of maize starch during an ecological nixtamalization process. Thermal and rheological properties of maize starch changed during the ecological nixtamalization process because of three main causes: the annealing phenomenon, type of calcium salt, and calcium salt concentration. In all treatments thermal properties (To, Tp, and Tf) of nixtamal starch increased owing to the annealing process, whereas the type of salt or lime increased thermal properties and decreased pasting properties in this order: CaCl2 > CaSO4 > Ca(OH)2 ≈ CaCO3. This behavior was because of the dissociation of each salt or lime in water. Anions (OH−) can penetrate much more easily into the starch granule and start the gelatinization process by rupturing hydrogen bonds. Additionally, amylose‐lipid complexes were formed during the nixtamalization processes, as indicated by an increasing peak at 4.5 Å in X‐ray diffraction patterns. 相似文献