Dietary glycine supplementation enhances syntheses of creatine and glutathione by tissues of hybrid striped bass(Morone saxatilis ♀ × Morone chrysops ♂) fed soybean meal-based diets

Background We recently reported that supplementing glycine to soybean meal-based diets is necessary for the optimum growth of 5-to 40-g(Phase-I)and 110-to 240-g(Phase-II)hybrid striped bass(HSB),as well as their intestinal health.Although glycine serves as an essential substrate for syntheses of creatine and glutathione(GSH)in mammals(e.g.,pigs),little is known about these metabolic pathways or their nutritional regulation in fish.This study tested the hypothesis that glycine supplementation enhances the activities of creatine-and GSH-forming enzymes as well as creatine and GSH availabilities in tissues of hybrid striped bass(HSB;Morone saxatilis♀×Morone chrysops♂).Methods Phase-I and Phase-II HSB were fed a soybean meal-based diet supplemented with 0%,1%,or 2%glycine for 8 weeks.At the end of the 56-d feeding,tissues(liver,intestine,skeletal muscle,kidneys,and pancreas)were collected for biochemical analyses.Results In contrast to terrestrial mammals and birds,creatine synthesis occurred primarily in skeletal muscle from all HSB.The liver was most active in GSH synthesis among the HSB tissues studied.In Phase-I HSB,supplementation with 1%or 2%glycine increased(P<0.05)concentrations of intramuscular creatine(15%–19%)and hepatic GSH(8%–11%),while reducing(P<0.05)hepatic GSH sulfide(GSSG)/GSH ratios by 14%–15%,compared with the 0-glycine group;there were no differences(P>0.05)in these variables between the 1%and 2%glycine groups.In Phase-II HSB,supplementation with 1%and 2%glycine increased(P<0.05)concentrations of creatine and GSH in the muscle(15%–27%)and liver(11%–20%)in a dose-dependent manner,with reduced ratios of hepatic GSSG/GSH in the 1%or 2%glycine group.In all HSB,supplementation with 1%and 2%glycine dose-dependently increased(P<0.05)activities of intramuscular arginine:glycine amidinotransferase(22%–41%)and hepaticγ-glutamylcysteine synthetase(17%–37%),with elevated activities of intramuscular guanidinoacetate methyltransferase and hepatic GSH synthetase and GSH reductase in the 1%or 2%glycine group.Glycine supplementation also increased(P<0.05)concentrations of creatine and activities of its synthetic enzymes in tail kidneys and pancreas,and concentrations of GSH and activities of its synthetic enzymes in the proximal intestine.Conclusions Skeletal muscle and liver are the major organs for creatine and GSH syntheses in HSB,respectively.Dietary glycine intake regulates creatine and GSH syntheses by both Phase-I and Phase-II HSB in a tissue-specific manner.Based on the metabolic data,glycine is a conditionally essential amino acid for the growing fish.

Hypomethylation of glycine dehydrogenase promoter in peripheral blood mononuclear cells is a new diagnostic marker of hepatitis B virus-associated hepatocellular carcinoma

Background: Glycine dehydrogenase(GLDC) plays an important role in the initiation and proliferation of several human cancers. In this study, we aimed to detect the methylation status of GLDC promoter and its diagnostic value for hepatitis B virus-associated hepatocellular carcinoma(HBV-HCC). Methods: We enrolled 197 patients, 111 with HBV-HCC, 51 with chronic hepatitis B(CHB), and 35 healthy controls(HCs). The methylation status of GLDC promoter in peripheral mononuclear cells(PBMCs) was identified by methylation specific polymerase chain reaction(MSP). The mRNA expression was examined using real-time quantitative polymerase chain reaction(q PCR). Results: The methylation frequency of the GLDC promoter was significantly lower in HBV-HCC patients(27.0%) compared to that in CHB patients(68.6%) and HCs(74.3%)( P < 0.001). The methylated group had lower alanine aminotransferase level( P = 0.035) and lower rates of tumor node metastasis(TNM) Ⅲ/Ⅳ( P = 0.043) and T3/T4( P = 0.026). TNM stage was identified to be an independent factor for GLDC promoter methylation. GLDC mRNA levels in CHB patients and HCs were significantly lower than those in HBV-HCC patients( P = 0.022 and P < 0.001, respectively). GLDC mRNA levels were significantly higher in HBV-HCC patients with unmethylated GLDC promoters than those with methylated GLDC promoters( P = 0.003). The diagnostic accuracy of alpha-fetoprotein(AFP) combined with GLDC promoter methylation for HBV-HCC was improved compared with that of AFP alone(AUC: 0.782 vs. 0.630, P < 0.001). In addition, GLDC promoter methylation was an independent predictor for overall survival of HBV-HCC patients( P = 0.038). Conclusions: The methylation frequency of GLDC promoter was lower in PBMCs from HBV-HCC patients than that from patients with CHB and HCs. The combination of AFP and GLDC promoter hypomethylation significantly improved the diagnostic accuracy of HBV-HCC.

Research on strategies for reducing the irritability of potassium cocoyl glycinate in cleansing

Background:Potassium cocoyl glycinate,a kind of amino acid surfactant,is widely used as major component for facial cleansing.However,the interaction between surfactants and compounds in the stratum corneum has been suggested as a contributing factor to their potential skin irritancy.Objective:This study aimed to the effects of adding surfactants,polymers,lipids and active substances on diminishing skin irritation caused by potassium cocoyl glycinate.Materials and methods:Zein test and Hemolysis test enabled the identification of irritation to proteins and cells in the studied binary systems.The critical micelle concentration(CMC)was evaluated by the surface tension method.The power of the analyzed polymers to diminish irritation of potassium cocoyl glycinate was represented by the reduction rate.Results:(1)Amphoteric surfactants and nonionic surfactants are effective at reducing the irritation of potassium cocoyl glycinate in some cases by reducing CMC;(2)Addition of polymers to the potassium cocoyl glycinate solutions improves its safety of use.Hydroxypropyl methylcellulose could reduce the irritation by 88.63%;(3)Combining most lipids can assist in declining the irritation,Lppg-28-Buteth-35 could inhibit the irritation of red blood cells by 16.52%;(4)The effects of active substances varied,hydrolyzed sodium hyaluronate results in a significant reduction in irritation to cells.Conclusion:In facial cleansers based on potassium cocoyl glycinate,supplying co-surfactant,polymers,lipids and active substances can reduce the irritation to some extent,however,the effects are various.

Performance in Survival,Development and Reproduction of Aphis glycines Matsumura Virginoparae at High Temperatures

The soybean aphid,Aphis glycines Matsumura,is an important pest of soybean,which is native to Asia.In this study,A.glycines fed on soybean(AgFS)and A.glycines fed on wild soybean(AgFW)were reared at 25℃,27℃,29℃,31℃,33℃and 35℃,respectively,and some of the life parameters were determined.At temperature ranging from 25℃to 31℃,nymphs of AgFS and AgFW all developed into adults successfully.Only a few nymphs of AgFS and AgFW developed into adults at 33℃and no nymphs could develop into adults at 35℃.Lifespan,fecundity and body size of AgFS and AgFW adults all decreased gradually with temperatures increasing from 25℃to 33℃.At 25℃,the intrinsic rate of increase of AgFS was as big as that at 27℃,which was smaller than that at 29℃,but was bigger than that at 31℃.Intrinsic rate of increase of AgFW decreased gradually with temperatures increasing from 25℃to 31℃.Nymph stage duration of AgFW was longer than or as long as that of AgFS;adult lifespan of AgFW was shorter than or as long as that of AgFS.Adult fecundity,intrinsic rate of increase and adult body size of AgFW were all smaller than or as big as those of AgFS.It showed that AgFS and AgFW both survived and developed well at temperature ranging from 25℃to 31℃,and AgFW was more adaptive to low temperatures.These results were important to study the adaptability of A.glycines to high temperatures and for predicting its dynamics in the temperature keeping rising region.

甘氨酸锰对产蛋后期蛋鸡产蛋性能和肠道微生物的影响

本试验旨在研究甘氨酸锰对产蛋后期蛋鸡盲肠微生物和产蛋性能的影响。选取体况良好、产蛋率接近的70周龄海兰褐蛋鸡720只,随机分为4个处理,每处理6个重复,每个重复30只鸡。基础饲粮不额外添加锰源(实测锰含量为21.77 mg·kg^(-1)),试验组饲粮在基础饲粮中分别添加120 mg·kg^(-1)锰的一水硫酸锰以及40、80和120 mg·kg^(-1)锰的甘氨酸锰(实测锰含量分别为144.46、57.84、96.97和135.59 mg·kg^(-1)),试验期12周(70~82周龄)。结果表明,40 mg·kg^(-1)锰的甘氨酸锰饲粮组蛋鸡77~82周龄产蛋率显著高于120 mg·kg^(-1)锰的一水硫酸锰组和80 mg·kg^(-1)锰的甘氨酸锰组(P<0.05),添加甘氨酸锰对70~82周龄产蛋率有增加的趋势(P=0.071),对70~82周龄其它产蛋性能指标无显著影响(P>0.05)。40 mg·kg^(-1)甘氨酸锰饲粮组蛋鸡盲肠微生物区系的Chao1和Shannon指数显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05),OTU数量最多,表明菌群多样性和丰富度最高;属水平上Top 10的菌属追溯到门水平上,120 mg·kg^(-1)一水硫酸锰组厚壁菌门(Firmicutes)相对丰度显著高于80 mg·kg^(-1)甘氨酸锰饲粮组(P<0.05);120 mg·kg^(-1)一水硫酸锰组中起重要作用的微生物类群集中在Firmicutes苞菌科(Selenomonadaceae),80 mg·kg^(-1)甘氨酸锰饲粮组中起重要作用的微生物类群集中在螺旋体门(Spirochaetota)螺旋体科(Spirochaetaceae);差异菌分析发现,40 mg·kg^(-1)甘氨酸锰饲粮组盲肠中乳酸杆菌属(Lactobacillus)相对丰度显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05),80 mg·kg^(-1)甘氨酸锰饲粮组类芽孢杆菌属(Paenibacillus)、马赛菌属(Massilia)和弯曲杆菌属(Campylobacter)相对丰度均显著高于120 mg·kg^(-1)一水硫酸锰组(P<0.05);与40 mg·kg^(-1)甘氨酸锰饲粮组相比,80 mg·kg^(-1)和120 mg·kg^(-1)甘氨酸锰饲粮组有益菌巨单胞菌属(Megamonas)、Lactobacillus和罗姆布茨菌属(Romboutsia)相对丰度显著降低(P<0.05),有害菌Campylobacter相对丰度显著提高(P<0.05)。由此可见,在本试验条件下,饲粮中添加40 mg·kg^(-1)锰的甘氨酸锰可以改善产蛋后期蛋鸡肠道微生物区系的物种丰富度和多样性指数,增加有益菌丰度和参与代谢过程的菌群,在一定程度上改善了试验后段(77~82周龄)蛋鸡产蛋性能。

A novel procedure for identifying a hybrid QTL-allele system for hybrid-vigor improvement, with a case study in soybean(Glycine max)yield

“Breeding by design” for pure lines may be achieved by construction of an additive QTL-allele matrix in a germplasm panel or breeding population, but this option is not available for hybrids, where both additive and dominance QTL-allele matrices must be constructed. In this study, a hybrid-QTL identification approach, designated PLSRGA, using partial least squares regression(PLSR) for model fitting integrated with a genetic algorithm(GA) for variable selection based on a multi-locus, multi-allele model is described for additive and dominance QTL-allele detection in a diallel hybrid population(DHP). The PLSRGA was shown by simulation experiments to be superior to single-marker analysis and was then used for QTL-allele identification in a soybean DPH yield experiment with eight parents. Twenty-eight main-effect QTL with 138 alleles and nine QTL × environment QTL with 46 alleles were identified, with respective contributions of 61.8% and 23.5% of phenotypic variation. Main-effect additive and dominance QTL-allele matrices were established as a compact form of the DHP genetic structure. The mechanism of heterosis superior-to-parents(or superior-to-parents heterosis, SPH) was explored and might be explained by a complementary locus-set composed of OD+(showing positive over-dominance, most often), PD+(showing positive partial-to-complete dominance, less often) and HA+(showing positive homozygous additivity, occasionally) loci, depending on the parental materials. Any locus-type, whether OD+, PD + and HA+, could be the best genotype of a locus. All hybrids showed various numbers of better or best genotypes at many but not necessarily all loci, indicating further SPH improvement. Based on the additive/dominance QTL-allele matrices, the best hybrid genotype was predicted, and a hybrid improvement approach is suggested. PLSRGA is powerful for hybrid QTL-allele detection and cross-SPH improvement.

垄作和覆膜下盐碱地水盐运移和大豆产量的变化

选择河北省黄骅市中度盐碱土区布置夏播大豆[Glycine max(L.)Merr.]田间试验,共设平播(对照)、平播覆膜、垄作及垄作覆膜4个处理,研究垄作和覆膜对土壤水盐运移和大豆产量的影响。结果表明,与传统平播方式相比,平播覆膜处理对土壤水盐运移和大豆产量的影响不显著;垄作处理能显著改变土壤水盐分布,特别是大豆生长中后期降雨量开始减少后,垄作定植沟会产生叠加集雨效果,显著提高大豆生长中期0~20 cm和20~40 cm土壤含水量,减缓作物生长后期向表层返盐进程,有效降低土壤表层盐分含量,对保障大豆植株生长和产量均有一定的促进效果,可增产27.2%;垄作覆膜处理效果与垄作处理类似,覆膜措施影响不显著。垄作技术可以作为滨海盐碱地夏播大豆种植的农耕措施。

双氯磺草胺在东北地区春大豆田的应用效果

为明确双氯磺草胺土壤封闭与茎叶处理对东北地区春大豆田阔叶杂草的防除效果和对作物的安全性。采用随机区组设计,连续2年开展田间试验。结果表明:25.2~76.5 g/hm^(2)有效成分剂量下84%双氯磺草胺水分散粒剂用于大豆田进行土壤封闭处理,施药后60 d,对东北地区常见阔叶杂草藜、本氏蓼、苍耳、苘麻、水棘针的株防效和鲜重防效都在90.0%以上,对龙葵的株防效和鲜重防效都在87.0%以上。对阔叶杂草的总株防效为93.3%~99.0%,总鲜重防效为94.7%~99.4%。25.2~63.0 g/hm^(2)有效成分剂量下84%双氯磺草胺水分散粒剂茎叶喷雾处理,施药后30 d,对本氏蓼、苍耳、苘麻的株防效和鲜重防效都在93.0%以上,对水棘针的株防效和鲜重防效都高于82.0%,对藜、龙葵的株防效为59.8%~85.5%,鲜重防效为62.5%~90.9%。对阔叶杂草总的株防效为80.1%~93.2%,总的鲜重防效为82.2%~95.9%,施药后初期,大豆叶片有受害症状,后期新生叶片正常。双氯磺草胺土壤封闭和茎叶喷雾施药方式都能有效控制东北地区春大豆田的阔叶杂草,但依据大豆产量分析,84%双氯磺草胺水分散粒剂有效剂量25.2~76.5 g/hm^(2)4个土壤封闭处理区大豆产量与人工除草相比差异不显著。本试验为大豆田苗后除草剂选择提供了新思路,茎叶喷雾施药方式适宜的剂量为84%双氯磺草胺水分散粒剂31.5~37.8 g/hm^(2);土壤封闭施药方式具有更好的除草效果,适宜的施药剂量为84%双氯磺草胺水分散粒剂25.2~50.4 g/hm^(2)。

铜调节的细胞死亡相关基因与前列腺癌关系分析

目的基于美国癌症肿瘤基因图谱(the cancer genome atlas,TCGA)数据库分析铜调节的细胞死亡相关基因与前列腺癌患者预后和免疫细胞浸润的关系。方法从TCGA数据库下载所有前列腺癌患者的基因数据,其中包括前列腺癌组织501例,正常组织52例。运用R软件提取前列腺癌患者中铜调节的细胞死亡相关基因表达矩阵,进行差异分析、多因素回归分析筛选出预后基因,对预后基因进行生存分析,同时探讨预后相关基因与免疫细胞之间的相关性。结果甘氨酸裂解系统蛋白H(GCSH)与前列腺癌患者的预后显著相关,同时发现其与前列腺癌患者中的树突细胞、CD8^(+)T细胞、浆细胞也显著相关(P<0.05)。结论GCSH基因在前列腺癌的发生、发展中起重要作用,有望成为前列腺癌预后的标志物。

甘氨酸与热力学抑制剂对甲烷水合物的协同抑制机理

天然气水合物在开采过程中,温度和压力的变化会导致分解后的水合物二次形成,进而会造成井筒和管线堵塞。甘氨酸因其强亲水性和生物可降解性,在水合物防治方面具有巨大应用潜力,但其与热力学抑制剂复配协同抑制水合物生成的作用机理尚不明确。为此,开展了甘氨酸与常见盐类和醇类热力学抑制剂复配使用时的甲烷水合物生成模拟实验,分析了甘氨酸与热力学抑制剂协同抑制甲烷水合物生成机理,并形成了适用于海洋水合物钻探开发用的甘氨酸类钻井液体系。研究结果表明:①甲烷气消耗量并不能真实反映抑制剂对水合物生成的抑制效果,还需结合水合物最终生成量、水合物生成3个阶段的时间变化情况综合判断;②甘氨酸浓度为1.0%时,抑制水合物生成的效果最佳,对应的反应体系具有最小的水合物生成区和最大的稳定区;③相比于单独使用1.0%甘氨酸,5.0%盐类抑制剂与1.0%甘氨酸混合使用时,具有协同抑制水合物生成的效果,可减少水合物生成量20%~30%,但5.0%醇类抑制剂与1.0%以及0.5%甘氨酸混合使用时反而促进了水合物生成;④甘氨酸与盐类混合形成的钻井液体系,可以有效降低水合物生成量。结论认为,该认识进一步厘清了甘氨酸与热力学抑制剂对水合物的协同抑制机理,为解决水合物开采过程中井筒堵塞造成的钻井安全问题提供了实验数据和理论支撑。

大豆对胞囊线虫(Heterodera glycines Ichinohe)1号和4号生理小种抗性的遗传分析

大豆胞囊线虫(Heterodera glycinesIchinohe)是我国大豆的全国性主要病害之一。1号和4号生理小种是黄淮地区的优势小种。以Essex×ZDD2315、Peking×ZDD2315、PI88788×ZDD2226、Peking×ZDD2226的P1、P2、F1、BC1F2为材料,用主基因+多基因混合遗传模型分析大豆对胞囊线虫1号和4号生理小种抗性的遗传机制。结果表明,ZDD2315、ZDD2226对1号生理小种的抗性受主效基因控制,未发现多基因效应,且与Peking存在相同的抗病基因;抗性遗传表现组合特异性,Essex×ZDD2315组合为3对加性主基因遗传模型,主基因遗传率72.02%,PI88788×ZDD2226组合为2对显性上位主基因遗传模型,主基因遗传率62.33%。对4号生理小种的抗性为主基因+多基因混合遗传模型,Essex×ZDD2315、Peking×ZDD2315、PI88788×ZDD2226等3个组合为3对主基因+多基因遗传模型,主基因遗传率分别为67.76%7、2.46%和53.25%,多基因遗传率分别为24.48%、21.31%和35.77%;Peking×ZDD2226表现为2对主基因遗传模型,主基因遗传率45.40%。抗性基因表现为隐性,育种上可以在早代选择。培育多抗品种应以抗4号生理小种为主要目标进行基因聚合。

大豆属Glycine亚属植物花粉形态研究

对大豆属Glycine亚属中10个种的花粉进行了光学显微镜和扫描电镜的观察.发现多倍体材料的花粉大于二倍体的.并发现Glycine亚属诸种花粉的形状、萌发孔、外壁纹饰均存明显差异.

干旱和复水对大豆(Glycine max)叶片光合及叶绿素荧光的影响

选用河南省大面积种植的大豆品种豫豆29作为实验材料,通过研究逐步干旱和旱后复水条件下大豆叶片光合、叶绿素荧光等指标随土壤水分的动态变化规律,以期为大豆的水分高效利用提供理论依据。研究发现,在土壤相对含水量高于46.5%时,虽然随着土壤相对含水量的下降,豫豆29仍可以保持它的叶片水分状态;豫豆29的叶片净光合速率在土壤水分中等条件下最大,在土壤相对含水量为64.3%时,它比对照组高出11.2%(P<0.01);在实验的第3d,处理组的土壤相对含水量降为46.5%,叶片水势与对照组相比降低了7.2%(P>0.05),净光合速率为对照组的89.6%(P<0.05),但气孔导度却迅速下降为对照组的44.7%(P<0.01),这说明与叶片的光合和水分状况相比,豫豆29的气孔对土壤水分的匮缺更加敏感。复水后,豫豆29叶片的水势、净光合速率、气孔导度和叶绿素荧光等值都可以得到迅速的恢复,并在实验的最后接近对照组的水平,这表明豫豆29的叶片光合在水分胁迫解除后有迅速恢复的能力。

Studies of Glycine Betaine on Physiology of Two Varieties of Pumpkin Seedlings under NaCl Stress

[Objective] The research aimed to discuss the relationship between Glycine betaine and the salt-tolerance mechanism of different pumpkins and confirm the mechanism of betaine in salt-tolerance physiology.[Method] Taking the seedlings of C.ficifolia and Qingli pumpkin as test materials,the effects of glycine betaine on the cell membrane permeability,MDA and root activity of two varieties of pumpkin seedlings under 300 mmol/L NaCl stress were studied.[Result] At suitable concentrations,glycine betaine could d...

铜、砷及其复合污染对黄豆(Glycine max)影响的初步研究

通过水培实验研究了Cu、As单一及复合污染对黄豆种子萌发、幼苗生长及部分酶活性的影响 .结果表明 ,Cu、As污染明显抑制黄豆种子萌发、幼苗生长 ,对黄豆种子萌发时的呼吸强度、蛋白酶活性有显著的抑制作用 ,且随着Cu、As浓度的增加 ,抑制作用增强 ,呈负相关 ;而POD活性则随污染物浓度的增加而增加 ,呈正相关 .Cu、As污染共同存在时 ,随二者投加比例不同出现不同程度的拮抗效应 。

Discussion on the Problem of Salt Gland of Glycine soja

Glycine soja Sieb. et Zucc. plants living in saline soil in three provinces of China were treated with different salinity concentrations under different laboratory culture conditions (including solution, sand and field cultivation). The attachment shape and distribution on the surface of stalk and leaf of G. soja plants were observed with scanning electron microscopy (SEM), and the ultrastructure of glandular hair with transmission electron microscopy (TEM). Na+ and Cl- contents in the secretion of the leaf surface and inside the leaf of G. soja subjected to different treatments were measured. The Na+ relative contents in glandular cells, epidermal cells and mesophyllous cells of leaves under different salinities were determined by X-ray microanalysis. Results show that only glandular and epidermal hair exist on the surface attachments of leaves and stalks of G. soja plants. These glandular hair were similar in shape to some salt glands of Gramineae halophytes, and they attached to the vein on the leaf surface. The cell structure of the glandular hair showed the characteristics of common salt glands, such as big vacuoles, dense cytoplasm, a great deal of mitochondria, chloroplast, plasmodesmata and thicker cell walls, etc. The results of Na+ and Cl- contents in the leaf secretion and inside the leaf showed that the glandular hair executed the function of salt-secretion, and when treated with the salt gland inhibitor the salt-secretion process was inhibited. As a result, Na+ and Cl- were mainly accumulated inside G. soja leaves. The results of Na+ X-ray microanalysis under different salinities proved that the three cells of the glandular hair, especially the top cell, possessed strong competence for Na+ accumulation. Above all, the glandular hair were the salt gland, and no other kind of salt glands were found on G. soja plants. The secreting mechanism of the salt gland was also discussed.

Cd Distribution and Subcellular Localization in Leaf and Its Effects on Growth of Soybean(Glycine max) Seedlings

In order to investigate Cd accumulation, subcellular distribution, and local-ization in soybean seedlings leaves, soybean seedlings were cultivated in solution containing different concentrations of Cd. The results showed that most Cd associ-ated with the cellwal s and soluble fractions, and a minor part of Cd presented in mitochondria fractions, nuclear and chloroplast fractions, especial y exposure to high Cd concentrations. Under 20.00 mg/L Cd stress, Cd subcellular distribution fol owed a sequence as： soluble fractions （55.00%）＆gt;cellwal s （30.0%）＆gt;mitochondria fractions （8.21%）＆gt;nuclear and chloroplast fractions （6.79%）. Deposited Cd black particles were observed in cellwal s, chloroplasts, nuclei, and vacuoles through electrical microscope slice. This fact indicated that the cellwal s of soybean leaves were the first protecting organel es from Cd toxicity, and the cellwal s and soluble fractions were the main place for Cd storage. Due to Cd accumulated in the organel es, the intercellular space was enlarged and the subcellular structure was damaged, especial y for the chloroplasts.

利用中国秋大豆(Glycine max(L.) Merr)筛选SSR核心位点的研究

选择中国秋大豆为试验材料 ,对基因组DNA进行SSR标记筛选和鉴定。经过 2 0 0个位点在琼脂糖胶上初筛和 96个位点在变性聚丙烯酰胺胶上复鉴 ,选出 6 0个位点 ,这些位点具有以下特点 :(1)分布在大豆 2 0个整合遗传连锁群 ,相邻位点间平均遗传距离在 5 0cM左右。除连锁群C2 、O上分别有 5个位点 ,G、K、M上分别有 2个位点外 ,其余 15个连锁群均分布有 3个位点 ;(2 )与 96个位点在 80份秋大豆种质检测到种质间遗传关系达到极显著相关 (r =0 .910 ) ;(3)在 80份秋大豆初选核心种质中表现出较高多态性 ,平均每个位点等位变异数为 9.3,多态性信息含量 (PIC)值为 0 .773;(4)在检测的秋大豆绝大多数种质基因组中 ,均为单一拷贝的位点 ,具有较高特异性 ;(5 )在相同的PCR扩增条件下 ,同一位点不同等位变异间易于识别且扩增强度较为一致。这套SSR核心位点的确定为中国大豆核心种质的构建奠定了基础。

不同茬口条件下的作物根渗出物对大豆胞囊线虫(Heterodera glycines)卵孵化影响

取北方5种作物轮作茬口和休闲土壤种植火豆、玉米、小麦、亚麻和甜菜,出苗后22 d制备作物的根渗出物,观察其对大豆胞囊线虫卯孵化的影响。试验表明,麦豆麦迎茬的甜菜根渗出物在后期大豆胞囊线虫(SCN)的卵孵化率最高,豆麦米轮作茬的大豆根渗出物9 d后SCN的卵孵化率明显高于其它作物,米豆米茬口的玉米根渗出物SCN的卵孵化率较高,豆麦豆迎茬甜菜根渗出物SCN的卵孵化率明显高于所有供试作物,12年大豆连作茬甜菜从一开始卵孵化率就高于对照和其它4种作物,休闲区的5种作物根渗出物也有对SCN卵孵化的刺激作用。

Identification and fine mapping of qSW2 for leaf slow wilting in soybean

Drought is one of the abiotic stresses limiting the production of soybean(Glycine max).Elucidation of the genetic and molecular basis of the slow-wilting(SW)trait of this crop offers the prospect of its genetic improvement.A panel of 188 accessions and a set of recombinant inbred lines produced from a cross between cultivars Liaodou 14 and Liaodou 21 were used to identify quantitative-trait loci(QTL)associated with SW.Plants were genotyped by Specific-locus amplified fragment sequencing and seedling leaf wilting was assessed under three water-stress treatments.A genome-wide association study identified 26 SW-associated single-nucleotide polymorphisms(SNPs),including three located in a 248-kb linkage-disequilibrium(LD)block on chromosome 2.Linkage mapping revealed a major-effect QTL,qSW2,associated with all three treatments and adjacent to the LD block.Fine mapping in a BC_(2)F_(3) population derived from a backcross between Liaodou 21 and R26 confined qSW2 to a 60-kb interval.Gene expression and sequence variation analysis identified the gene Glyma.02 g218100,encoding an auxin transcription factor,as a candidate gene for qSW2.Our results will contribute significantly to improving drought-resistant soybean cultivars by providing genetic information and resources.