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用奎吖咽(quinacrine)作荧光指标剂,测定玉米(ZeamaysL.)根尖微粒体(MIC)膜囊泡的H~+-泵活性,结果表明1mmol/LNaN_3仅抑制该泵活性约8%,而0.8mmol/L钒酸盐(Van)则可抑制其活性达80%,说明MIC制剂中H~+-泵活性主要由质膜(PM)H~+-ATPase产生。此泵活性严格需要Mg~(2+),二价阳离子作用大小的顺序为Mg~(2+)>Mn~(2+)>Zn~(2+)>Ca~(2+)=0;阴离子作用大小的1顺序为Br~->Cl~->NO_3~->SO_4~(2-),并初步证实当质膜同侧发生电子传递时,没有跨膜H~+梯度(△μH~+)生成。 相似文献
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S. Chao C. Baysdorfer O. Heredia-Diaz T. Musket G. Xu E. H. Coe Jr 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(6-7):717-721
We report here the results of mapping a set of 92 leaf cDNA clones in maize. The ends of each of these cDNA clones have previously been partially sequenced, and the sequence comparison has revealed the putative function for 28 clones. It is expected that the RFLP map developed using these expressed sequence tags will be of great importance for future maize genome analysis, such as for PCR-based gene mapping or gene function identification.Contribution from the Missouri Agricultural Experiment Station. Journal Series N. 12,019. 相似文献
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Linkage disequilibrium in crosses between Illinois maize strains divergently selected for protein percentage 总被引:1,自引:0,他引:1
J. W. Dudley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,87(8):1016-1020
The objectives of this study were two fold: (1) to determine whether divergent selection for kernel protein concentration, which produced the Illinois high protein (IHP), Illinois low protein (ILP), reverse low protein (RLP), and reverse high protein (RHP) maize (Zea mays L.) strains, had generated coupling-phase linkages among genes controlling protein concentration or other traits and (2) to measure the effectiveness of random mating in reducing linkage disequilibrium in segregating generations from crosses between the strains. To achieve these objectives, design III progenies from the F2 and F6 (produced by random mating the F2) from the crosses of IHP × ILP, IHP × RHP, ILP × RLP, and RHP × RLP were evaluated. Estimates of additive variance for percent protein in the crosses of IHP × ILP and ILP × RLP were significantly less in the F6 than in the F2 indicating the presence of coupling-phase linkages in the parents and their breakup by random mating. In addition, a significant reduction in dominance variance for grain yield from the F2 to the F6 in IHP × ILP suggested the presence of repulsion-phase linkages. No other evidence of coupling or repulsion-phase linkages was found for any of the traits measured. These results demonstrate the effectiveness of long-term divergent selection in the development of coupling-phase linkages and of random mating to dissipate linkage disequilibrium.Research supported by the Illinois Agricultural Experiment Station 相似文献
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Two cDNA clones corresponding to anaerobically induced maize mRNAs were found to have homology to a previously identified maize pyruvate decarboxylase gene. DNA sequencing and RFLP mapping indicate that these cDNAs represent two additional maize pdc genes. Each of the clones is approximately 85% identical in predicted amino acid sequence to the other two. All three clones are induced by hypoxic stress, but with different levels and kinetics of induction. 相似文献
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《Saudi Journal of Biological Sciences》2023,30(1):103491
Post-harvest losses for maize and beans are common storage challenges affecting Tanzania's smallholder and large-scale farmers' storage facilities. Consequently, this leads to a reduction of over 50% of harvested grain qualitatively and quantitively per year. Therefore, this experimental study was conducted at the entomological laboratory of the Sokoine University of Agriculture Tanzania, where the research was aimed to assess different common storage insect pests of beans and maize at Morogoro major markets (i.e., Kihonda, Mazimbu and Morogoro Central Market) with similar storage conditions in Morogoro municipality. The complete block design (CBD) with three experimental replications was used. Where locations (Kihonda, Mazimbu and Central market) markets were considered as experimental treatments. The results obtained show that there were no significant differences in number of insect pests (such as maize weevils and bean bruchids) identified between the Kihonda and Central markets (P > 0.05). However, there is a significant difference (P< 0.05) between Mazimbu and other markets regarding the number of insect pest multiplication resulting from the storage condition of those grains in a particular market. Nevertheless, continuous winnowing of stored grains was observed to significantly intensify the infestation of the storage pest in maize and common beans. Therefore, alternatively, to reduce insect pest infestation to maize and common beans in storage facilities, it is important to avoid constant winnowing of stored grains. 相似文献
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Riccardo Fedeli Andrea Vannini Martina Grattacaso Stefano Loppi 《The Annals of applied biology》2023,183(2):135-140
Potato is the fourth most widely consumed staple food in the world. This study investigated the effectiveness of 0.2% wood distillate (WD), a biostimulant derived from the pyrolysis of waste plant biomass, in boosting the nutritional quality of potato tubers. The results showed that application of WD significantly increased the content of soluble sugars (sucrose +56.3%; glucose +44.9%; fructose +62.2%), starch (+35.1%) and total carbohydrates (+16.8%). Antioxidants (total antioxidant power, polyphenols, flavonoids) and most mineral elements (K, Mg, Ca, Na, Fe, Zn) were not affected. A lower content of Cu (−17.8%) and P (−24.5%) was found in WD-treated potato. 相似文献