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101.
The incubation period ofM. incognita acrita eggs took 24–72 hours till the appearance of the second larval stage hatching from eggs in the laboratory at 25±5°C and at 60±5 R. H. The second larval stage, was observed in cotton roots 48 hours after the addition of it to soil beside cotton seedlings. The 3rd and 4th larval stage and adult female were observed in cotton roots 7, 11, and 24 days, respectively, after the addition of second larval stage to soil beside cotton seedlings. The total life cycle ofM. incognita acrita on cotton, (Gossypium barbadense) lasted for 33–38 days, at 25±5°C and at 60±5 R. H.  相似文献   
102.

Background  

The data generated during a course of a biological experiment/study can be sometimes be massive and its management becomes quite critical for the success of the investigation undertaken. The accumulation and analysis of such large datasets often becomes tedious for biologists and lab technicians. Most of the current phenotype data acquisition management systems do not cater to the specialized needs of large-scale data analysis. The successful application of genomic tools/strategies to introduce desired traits in plants requires extensive and precise phenotyping of plant populations or gene bank material, thus necessitating an efficient data acquisition system.  相似文献   
103.
Indigenous perennial grasses are widely distributed in the Arabian Peninsula. Their survival under limited rainfall and grazing suggests a potential role as grassland species and for rehabilitation of degraded rangelands. Forage productivity, seed production and water‐use efficiency (WUE) was determined over 2 years for four indigenous grasses: buffel grass (Cenchrus ciliaris L.), dakhna (Coelachyrum piercei Benth.), da’ay (Lasiurus scindicus Henr.) and tuman (Panicum turgidum Forssk.) together with one exotic species, rhodes grass (Chloris gayana Kunth) in the central region of the United Arab Emirates. Three irrigation treatments were used: R1 (1858–6758 m3 ha?1 year?1), R2 (929–3379 m3 ha?1 year?1) and R3 (464–1689 m3 ha?1 year?1). Buffel grass had the highest dry‐matter (DM) yield under all irrigation treatments. The average DM yield of buffel grass was 14·6 and 15·1 t ha?1 in the 2 years which was significantly higher than that for the other grasses with dakhna having the lowest DM yields. The WUE of 0·7 and 0·8 kg DM m?3 in the 2 years for buffel grass was significantly greater than for the other grasses. Buffel grass showed the highest increase in WUE in both years when the irrigation was reduced from treatment R1 to R3. The results suggest that the desert grasses of the Arabian Peninsula, such as buffel grass, could be useful grass species in reducing the use of scarce irrigation water provided that seed production can be increased.  相似文献   
104.
Field experiment was conducted at a site naturally infested withTylenchulus semipenetrans to explore the effect of sincocin AGTM as a biocidal agent at 2000 ppm in controlling citrus nematodes. Sincocin AGTM significantly reduced citrus nematode population in both soil and roots ofCitrus sinesis, and enhanced both growth of orange trees and soil mites especially the mesostigmatide mites. In treated soil, the nature nematode feeders, mesostigmatide mites were increased by 140% and 243%, one month and two months, respectively, post application.  相似文献   
105.
In this study, the electric current of polymer solution jet was measured during a needleless rod electrospinning process using memory oscilloscope recording. According to the results, electric current of solution jet increases as the polyurethane (PU) and tetraethylammonium bromide (TEAB) salt concentration increase. Especially at 17.5 and 20 wt% PU concentrations, electric current increases dramatically with TEAB concentration. Also, there is a strong relationship between the electric current in the solution jet, spinnability and the spinning performance of the roller electrospinning. Thus, the spinnability of polymer solutions can be easily estimated using this simple method.  相似文献   
106.
Effect of some nutritional plant sprays on the population of Tetranychus arabicus (Attiah) (Acarina, Tetranychidae) Studies on the effect of inorganic compounds on the population density ofT. arabicus indicated that all materials gave over 50% reduction after 15 days except chromic chloride and magnesium oxide which gave only 33% each, while potassium iodine built up mites population. As such, these compounds are potentially important mites-control chemicals. Also data showed conclusively that inorganic compounds may be used as well to manipulate host plant resistance, as to correct crop nutritional difficiency. However, the mode of action and the time of application of these compounds under natural field conditions still need further investigations.   相似文献   
107.
Summary Three methods that have been suggested as inexpensive for characterisation of gum arabic were evaluated in characterising and monitoring gum arabic of commerce. The methods were; physico-chemical and carbohydrate analysis (analytical), determination of molecular mass by gel permeation chromatography (gpc) and an Enzyme Linked Immunosorbent Assay (ELISA). The results revealed that gpc provides quick and consistent information on gum arabic of commerce from Acacia senegal. It was able to detect the three chemical species; Arabinogalactan protein complex (AGP), Arabinogalactan (AG) and Glycoprotein (GP) fractions that are typical of A. senegal and could differentiate gum from the two varieties of A. senegal, i.e., var. senegal and var. kerensis on the basis of the enhanced UV peaks in the later. It was able to distinguish gums from different Acacia species as well as suspected contaminants. The analytical method could differentiate between the two varieties of A. senegal on the basis of optical rotation, protein content and viscosity which were noted as basic parameters for comparison. However, where the proposed FAO (1990) specifiction was applied in its present form, it failed to adequately characterise gum from var. kerensis as gum arabic. Secondly, natural product variability i.e., the observed between sample variation made the method to have limited application in adequately characterising gum arabic from even a single source. The method was able to distinguish gums from the other Acacia species purely on the basis of optical rotation though information on nitrogen and sugar composition was also invaluable. Generating data on the composition of sugars requires time that militates against the method as a slow process. Because of the overlap in the analytical parameters for some samples, it could be adequately characterise two of the samples that were presented as suspected contaminants. Nonetheless, by combining information of gpc and analytical data, a better evaluation of the gums was achieved. The method of Elisa has a future scope but will require refining it by utilising monoclonal antibodies to be developed for it to be more specifc in characterising gum arabic from A. senegal. The authors wish to thank Dr. P. A. Williams of the North East Wales Institute, Deeside, Clwyd, UK for the use of the gpc and Elisa facilities. B.N.C. is grateful to the Kenyan and British governments for financial support.  相似文献   
108.
A suppressive effect was obtained by the henna plant (Lawsonia inermis) againstM. incognita development. Henna reduced tomato root gall numbers, number of the egg-laying females and rate of the nematode reproduction, when tomato and henna were grown together. Also, same, reduction in these nematode biological processes was found, when tomato plants were grown in soil containing root exudates of henna, but with less amount. When henna was grown alone, root gall index and the rate of nematode reproduction reduced to 75 and 99%, respectively, compared with those of tomato grown alone.  相似文献   
109.
Leaf beetle occurrence and abundance on certain shrubs and bushes were surveyed during 2002–2003 in several natural habitats of Isparta. The 34 leaf-beetle species collected are listed and classified according to their relative percentage of the total caught and to their associated host plants. In all habitats sampled, leaf beetles showed a preference for plants from the genera Quercus and Crataegus. Some abundant species causing serious damage to their food plants are discussed.  相似文献   
110.
轮台属于大陆型气候,气候干燥,昼夜温差大,很适宜杏树的种植。但是该县杏树生产目前还是传统的粗放经营方式,产量低,品质差,效益低,严重影响其发展进程。因此,只有因地制宜的建立杏树生产基地,在进行集约化的土水肥管理和树体管理措施才能更好地适应市场需求,生产产量和品质较高的,适应国内外市场的优质商品果。在轮台小白杏的生物学特性,生长地环境进一步调查了解的基础上,对小白杏生产过程中采取的主要技术措施进行了分析和总结,结合小白杏的产量和品质,提出了比较适宜的高产并优质果生产的栽培管理的配套技术措施。认为在小白杏生产过程中只要采取规范化并集约化的栽培管理措施,可以提高产量和品质,达到提高经济效益的栽培目的。  相似文献   
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