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排序方式: 共有54条查询结果,搜索用时 171 毫秒
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Claude Bakoumé Benjamin Adon Benoît Cochard Françoise Potier Tristan Durand-Gasselin Philippe Amblard 《Euphytica》2001,121(1):59-64
Following a survey involving wild oil palm groves in Côte d’Ivoire as a whole in 1968, 17 parents were chosen at Yocoboué (southernCôte d’Ivoire). Agronomic performance of the 17 parents was assessed through Deli × Yocoboué hybrids in 3 trials grown at La Mé (Côte d’Ivoire), Mondoni and La Dibamba (Cameroon).When compared to the Deli × La Mé progenies used as controls, the Deli × Yocoboué hybrids produced 91% for total bunch weight and86% for oil yields. However, the genetic variability within the Deli × Yocoboué progenies allows to select individual progenies as productive as the Deli × La Mé controls, for breeding purposes. A study of major agronomic traits led to the choice of parent YO 11 T , which combines the largest number of favourable traits. On average, Deli × Yocobouéprogenies have slower vertical growth and are susceptible to Fusarium wilt, except 2 parents (YO 3 T and YO 9 T), which seem to be resistant. 相似文献
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J. B. Wonkyi-Appiah 《Euphytica》1987,36(2):505-511
Summary A study was conducted on the segregating populations from tenera × tenera, tenera x fertile Pisifera crosses and tenera selfings. Pisifera palms were categorised as (1) fertile Pisifera palms if producing mature ripe bunches regularly under natural conditions, and (2) partially female sterile pisifera palms if producing a few or no bunches in several years.Based on observations on the segregation patterns of the fruit forms (dura, tenera and pisifera) and bunch production patterns, a genetic model was formulated to explain the genetic basis of fertility in the oil palm. Fertility in the oil palm is shown to be controlled by a single gene which is linked to the gene controlling fruit form. Chi-square tests confirmed that the model agreed with the segregating ratios of fruit form and fertility observed.The implications of this finding with regard to oil palm breeding and improvement, and the potential of the fertile pisifera palm for increasing palm oil yields in plantations are discussed. 相似文献
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Spatial patterns of spear rot in oil palm plantations in Surinam 总被引:1,自引:0,他引:1
As the aetiology of spear rot of oil palm is unknown, indirect methods were applied to study its putative infectiousness by analysing data from commercial oil palm plantations in Surinam. Geostatistics and gradient analysis were used to examine the spatial variation of spear rot disease in 13 blocks at two plantations. In two blocks, which had low spear rot incidence initially, the variogram indicated that affected trees were not spatially related, suggesting that infection came from various distant sources. Later, the semivariances in one of these two blocks and in seven others, calculated for successive dates, showed a linear increase with distance. The variograms for four blocks showed a nonlinear increase in variance. Over the years, the variograms suggested that the variation in spear rot was anisotropic, with more spatial dependence in a westerly direction. Classical analysis of disease gradients over time confirmed that there was a preferential direction of disease spread. The data are compatible with the following hypotheses: (1) spear rot is an infectious disease; (2) the causal agent of spear rot is vector-borne, the vector being displaceable by wind; and (3) spear rot appears in two distinct phases, phase 1 being characterized by few randomly scattered trees, phase 2 by focal spread of disease starting from such scattered trees. The trigger of the change from phase 1 to phase 2 remains unknown. 相似文献
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研究蒸馏水、0.8%柠檬酸提取液、60%酸性乙醇3种提取剂对油棕嫩果皮中花色苷稳定性的影响。结果表明,酸性乙醇对油棕嫩果皮花色苷的提取率最高,达到542μg/g;3种提取液在272 nm处有最大吸收峰,提取液中的组分均易溶于甲醇和丙酮;3种花色苷提取液在颜色的变化上随pH值变化一致;在日光照射和室内自然光条件下,花色苷柠檬酸提取液较为稳定,酸性乙醇提取液次之,蒸馏水提取液最差;在4~100℃的温度范围内,花色苷柠檬酸提取液较为稳定;蔗糖和葡萄糖添加量为20%时,对花色苷提取液基本无影响;花色苷柠檬酸提取液受金属离子影响较大,锌离子对花色苷提取液具有增色作用。 相似文献
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K. Dhileepan 《国际虫害防治杂志》2013,59(3):273-277
Abstract The common myna Acridotheres tristis Linn., the jungle crow Corvus macrorhynchus Wagner and the house crow Corvus splendens Viellot are the major pests of oil palm in India. Other birds like crow pheasant Centropus sinensis Stresmann, parrot Loriculus sp. and pariah kite Milvus migrans Sykes also feed on oil palm fruits. These birds feed on the fleshy mesocarp of the ripe fruits resulting in heavy fruit loss, significantly reducing oil yield. Gizzard and intestinal content analysis indicated that oil palm fruits are the major source of food for these birds. Observations on 1657 oil palm fruit bunches during 1985–86 revealed that 76% of the ripe bunches and 5.6% of the unripe bunches were damaged by birds. The damage by birds was either ‘partial’ or ‘complete’, where 40–50% and 80–100% respectively, of the individual fruit weight was lost. The partial fruit damage was more common in 130–160 day‐old bunches and the complete fruit damage increased after 150 days of fruit set. Fruit loss due to bird damage was higher in palms in the border area of the plantation (2.3 kg/bunch) than in the interior (1.3 kg/bunch). It is estimated that around 2.8 tonnes of fresh fruits/ha/yr, equivalent to 420 kg of palm oil, are lost due to bird damage. 相似文献
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P. Kastelein W. G. van Slobbe G. T. N. De Leeuw 《European journal of plant pathology / European Foundation for Plant Pathology》1990,96(2):113-117
Fatal yellowing in oil palms from Brazil and Ecuador is characterized by a chlorosis of the young unfolded leaves and a decay of spear leaves. Contrary to healthy-looking palms, diseased palms do not have roots with soft and white tips.In search for a possible causal agent of fatal yellowing, tissues of leaves, the apical region of stems and root tips of healthy-looking and diseased palms were examined by light microscopy. Fungi and bacteria were frequently, but not always found in necrotic lesions in the leaves. These organisms, however, have never been found outside the lesions or in the vascular tissues of affected palms, nor in the tissues of healthy-looking palms. Tyloses frequently occluded the xylem vessels of affected leaves. In a diseased palm from Ecuador hypertrophic cells were found in the epidermal layer of the pinnae of a spear leaf with water-soaked lesions. In the apical region of the stems and roots of diseased palms, only a few meristematic cells could be detected.Samenvatting Speerrot van oliepalmen in Brazilië en Ecuador wordt gekenmerkt door vergeling van de jongere, geheel geopende bladeren en een rot van de speer. In tegenstelling tot palmen zonder ziekteverschijnselen, hebben aangetaste palmen geen wortels met zachte, witte worteltoppen.Weefsel van bladeren, de apex van de stam en toppen van jonge wortels van gezonduitziende en zieke palmen werden m.b.v. de lichtmicroscoop onderzocht op de aanwezigheid van een eventueel pathogeen. Schimmels en bacteriën werden vaak, doch niet altijd, waargenomen in necrotische lesies op de bladeren, maar nooit buiten lesies of in de vaatbundels van zieke palmen en de weefsels van gezond-uitziende palmen. Vaak verstopten thyllen de houtvaten van aangetaste bladeren. In een speerblad van een zieke palm uit Ecuador werden enige gehypertrofieerde cellen waargenomen in de epidermis van pinnae met waterige lesies. In de top van de stammen en wortels werden slechts enkele meristematische cellen waargenomen. 相似文献
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Jose A. Cristancho Syed R. Syed Omar Mohamed Y. Rafii 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):487-498
Abstract Soil acidity is one of the main factors that limit profitable and sustained agricultural production. Oil palm (Elaeis guineensis Jacq.) is mainly planted in acidic soils. In the last years, there has been a stagnated yield and increases in disease incidence and severity worldwide that could be attributed in some extent to soil acidity. This study was conducted to determine the effects of soil acidity alleviation on oil palm seedlings. The effects of ground magnesium limestone or dolomite and magnesium carbonate (0, 1.1, 2.2, 3.3 and 4.4 t ha?1) applied to an Ultisol dominated by kaolinite (pH in water 4.4) were evaluated on selected morphological, physiological and nutritional characteristics of hybrid (Deli dura × AVROS pisifera) and clonal (clone 366) oil palm progenies under nursery conditions for 8 months. Increasing rates of ground magnesium limestone and magnesium carbonate showed a significant effect on improving soil pH and lowering exchangeable aluminium. The hybrid oil palm showed significant either linear or quadratic trends for most of the parameters evaluated, indicating that the best responses for morphological and physiological traits were achieved from 2.5 to 4.23 t ha?1 with ground magnesium limestone and 2.87 to 3.45 t ha?1 with magnesium carbonate. Positive effects of increasing rates of ground magnesium limestone and magnesium carbonate were observed on nitrogen and magnesium uptake. Aluminium concentration in the third frond decreased significantly with increasing ground magnesium limestone rate. A significant reduction of manganese uptake was also observed with increasing rates of both ameliorants. The clonal oil palm progeny exhibited a better performance on un-amended treatment. This may be explained by the significant higher root growth of this progeny. Soil acidity alleviation improved the oil palm seedling growth. These results are important for the oil palm industry and could be applied in the nursery stage as well as extended to the immature stage. 相似文献