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151.
Journal of Crop Science and Biotechnology - Phenotyping is the major bottleneck in the effort to develop varieties of rice (Oryza sativa L.) suitable for growing under a water-saving irrigation...  相似文献   
152.
Despite its economic importance and recent genome release, the need for molecular tools for Hevea brasiliensis is high. In the frame of a disease resistance study, EST sequences were retrieved from public database or generated by sequencing SSH libraries. Sequences were trimmed and microsatellite motifs searched using an ad hoc bioinformatic pipeline, and pairs of primers for the amplification of candidate markers were generated. We found a total of 10 499 unigenes from both sources of sequences, and 673 microsatellites motifs were detected using the default parameters of the pipeline. Two hundred sixty‐four primer pairs were tested and 226 (85.6%) successfully amplified. Out of the amplified candidate markers, 164 exhibited polymorphism. Relationships based on dendrograms using simple matching index and diversity statistics based on EST‐SSRs were compared with Genomic SSRs, showing the potentialities of EST‐derived microsatellites for resistance studies but also for population genetics approaches.  相似文献   
153.
The female line 1709, carrying the recessivecharacter green cotyledon, marker of the embryogenotype, was cross-pollinated by bees in the presenceof either male line HG115 or male line Dial63. In thecomparison of seeds which resulted either fromintercrossing or from selfing, a xenia effect wasobserved on volume and number of cotyledon cells andon individual seed weight which was dependent on themale line. The increase of hybrid seed weight inducedby the small-seeded male line Dial63 was larger thanthe one induced by the large-seeded male line HG115.The xenia effect on seed weight was correlated withthe level of heterosis in the F1 plant's growth.  相似文献   
154.
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   
155.
富氮低氧储存稻谷品质变化试验   总被引:1,自引:0,他引:1  
比较了在富氮低氧条件下储存三年的稻谷与常规磷化氢熏蒸储存稻谷品质变化.试验仓稻谷的发芽率下降了32%,对照仓下降了42%.试验仓脂肪酸值增加为4.0(KOH/干基)/(mg/100g),对照仓为6.3 (KOH/干基)/(mg/100g).品尝试验中,试验仓的品尝效果更好.  相似文献   
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为研究黄颡鱼同工酶系统的组织特异性,分析黄颡鱼的遗传多样性并为品种改良提供有价值的生化遗传指标。采用聚丙烯酰胺垂直凝胶电泳法,对黄颡鱼的血,腮,脑,肝,心,胃,肾,性腺,肌肉,肠,头肾,脾和膀胱共13种新鲜组织中的苹果酸脱氢酶(MDH)、苹果酸酶(ME)、超氧化物歧化酶(SOD)、酯酶(EST)、葡萄糖醛酸酐酶(GD)共5种同工酶进行了分析。结果表明,MDH在脑、肾和头肾中分别具有特异性酶带;ME只在肝组织检测到酶带;SOD在肝、肠、脑和肌肉组织分别具有特异性酶带,EST在肌肉组织具有特异性酶带;GD在腮和脑组织中具有特异性酶带。说明黄颡鱼5种同工酶系统具有明显的组织特异性。  相似文献   
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The Kyoto protocol [39] directs the signatory countries including France to establish an inventory of carbon stocks in forests. Precise estimates of carbon stocks are hampered by local spatial variability, in particular in wetland areas [25]. The aims of this work are: (i) to estimate the spatial variability of carbon stocks on two hillslopes presenting respectively, a transition between a well-drained zone and a wetland area over a short-distance, and a very progressive transition; (ii) to correlate this variability with soil waterlogging and topographic variations and (iii) to evaluate carbon stock prediction by modelling waterlogging intensity as soil organic carbon (SOC) stocks increase significantly with waterlogging. However, SOC stocks in redoximorphic soils are highly variable, particularly in zones where carbon is redistributed due to erosion and sedimentation. In the litter and the vegetation, the age and density of the stand are the main explanatory factors of C variability. Topographic modelling of the waterlogging intensity could improve the spatial estimation of SOC stocks but not of the C stocks in the humus and vegetation.  相似文献   
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