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the zein family had been extensively used f or corn cultivar identification. Different genotypes containing between 8 to 15 ponents has been identified from t heir zein bandpatterns on the isoelectric focusing electrophoregram. The zein IEF pat tern has been regarded as a genetic marker. The IEF w as also used in mapping of genes coding for zein. However, t he zein IEF pattern does not have enough capacity in differentiating between hybrids and their female inbred parents. Certain band differences could be detected among the inbred by using SDSPAGE procedure to analyze proteins extracted from t he seeds and seedlings, but this difference was influenced by t he buffer solution. From the prehensive survey of irony me variability in corn inbred and hybrids using SGE to fractionate proteins from 5day old coleoptiles tissue and staining f or 12 is enzymes, 88 out of 113 ( 80% ) public inbred being utilized in Canadian hybrids and 146 out of 155 ( 94% ) mercial hybrids w ere distinguished by using SDSPAGE procedures. T he heterogeneity of the album ins and goblins of corn seeds w as also used t o identify part of the corn inbred and hybrids. All of t he abovementioned electrophoresis procedures were carried out under basic pH condition. Wang et al. first used t he gradient palmary limed eagle electrophoresis to analyses the 1 mol/ L urea ex tract able proteins of corn seeds under acid pH condition and had been highly praised f or t he possible validity of t his method f or corn seed purity testing. An acid lactatePAGE procedure has been developed in our laboratory as a basic method of w heat cultivar electrophoresis identification. T his procedure was preliminarily proved t o be suit able for separating corn albumin and globulin fractions. The aim of t his study was to evaluate the feasibility of this procedure in distinguishing different corn genotypes, its resolving power, stability, reproducibility and t he genetic expression of parent inbred in term s of band patterns in their F1 hybrids, so as t o explore the possibility of its application on corn genetic purity testing and cultivar identification.1 MATERIALS AND METHODSSample preparationA tot al of 141 inbred and 153 hybrids of corn ( Zea mays) were studied. T he former prised of 9 high oil inbred developed from Illinois high oil ( IHO) C80, 14 high oil inbred from Alexon high oil synthetic C23, and 6 sweet corn inbred from a mercial single cross of Rogers Seed Co. T he latter prised of 26 hybrids w it h on female parents but different male parent s, and 16 w it h mon male but different female parents. All seed samples were provided by our own laboratory . A single corn seed w as ground w it h a sing le seed mill or soaked in tap water under 0 ℃ overnig ht , after which t he embryo and endosperm w ere dissected with a razor blade. After naturally dried, the embryo or endosperm was g round separately. T he ground powder w as put into 2. 5mL centrifuge tube, w it h t he addition of equalvolume of ex tract ion solution( 0. 5 mol/ L NaCl, containing 15% sucrose and 0. 05% methyl green) , mixed thoroughly and extracted for 1 h at room temperature, then centrifuged at 4000 r/ min f or 5 min. The supernatants were used f or electrophoresis.Preparation of the working solutionsT he stock solution, tank buffer, separation gel and concentration gel w ere preparedaccording t o the proportion and volume in T able 1.Table 1 Recipes for stock, extraction and buffer solutionsStock solutionsMixed ratio1 .A crylamide 95 g, Bisacrylamide 3. 8 g, distilled water 500mL2. Sodium lactate2. 81mL+lacticacid to pH3. 2,H2O100mL3 ,ferroussulfate(7H2O)8mg,H2O100mL4. Sodium lactate3mL+lactic acid to pH5. 6,H2O100mL5 A crylamide 26 g, bissacrylamide 5. 2 g, H2O 200mL6 A mmonium persulph at e 11. 41 g, H2O 100mL7 Distilled waterSeparation gel14ml2ml2ml8ul2mlConcertration gel1ml2ml80ulTank buffer: Glycine 4 g+ lactic acid to pH 3. 4, H2O 2000mLElectrophoresisT he vertical plate electro phoretic apparatus w as used w it h 11. 0mm10. 0mm0. 75mm gelslab. Electrophoresis w as carried out at 500 V, 30mA for 1. 5 h. The gel was stained with Coomassie Brilliant Blue R250 ( 40mL 0. 14% Coomassie Brilliant Blue R250alcohol solution dissolved in 12. 5% trichloroacetic acid 160 m L) .2 RESULTS AND DISCUSSIONResolving powerThis electrophoretic procedure showed hi