Inheritance of pseudo-self compatibility in self-incompatible garden and greenhouse chrysanthemums, Dendranthema grandiflora Tzvelv

Summary Self incompatibility (SI) can be used to alleviate costly hand emasculation and pollination in F₁ hybrid chrysanthemum seed production. SI, however, disrupts the progression of inbreedig (selfing or full-sib mating). Consequently, inbreds are selected for breakdown of the SI system or the presence of pseudo-self compatibility (PSC). PSC inbreds, recombinant inbreds, and noninbred cultivars were selfed and/or intercrossed to determine PSC expression across environments and generate 1–3 inbred generations (I₁–I₃). Percent PSC ranged from 0–68.8% for inbred parents, 0.2–99.7% for recombinant inbreds, and 0.6–25.7% for noninbred cultivars. There was no indication of end-of-season PSC. The majority of parents (78%) were classified as low PSC and this trend continued in the I₁ (70.1%), I₂ (65.6%), and I₃ (83.6%) generations; mid PSC was rarer (11.9–18.8%) and high PSC the least common (4.5–15.6%). PSC distributions were primarily continuous, rather than discrete, indicating quantitative inheritance. In several inbred families, 100% of the I₁ individuals were SI; this was not correlated with parental PSC level. Inbred families derived from selfing low and mid PSC parents were the most likely to reach extinction due to inbreeding depression. High PSC was not highly heritable, since I₁ progeny were predominantly SI or had low to mid PSC levels. Most 153-1 values for PSC:SI segregations (1:1, 1:3, 3:1) were not significant at the 5% level. Realized heritability (H _R ) estimates for PSC ranged from a low of 0.05% to 10.19%, although increased H _R values did not account for inbreeding depression or genetic mechanisms preventing selection for high PSC. The highest individual %PSC increased over the high parent with SI × low PSC or SI × mid PSC parents in all cases; progeny means did so only in SI × low PSC. Low × low crosses were split evenly between an increase and decrease in progeny or highest individual mean. Since all low × low crosses and low selfs produced 43–50% of the progeny with PSC levels higher than the parents, it appears that most low parents possess some unexpressed PSC genes. Mid PSC parents responded similarly to low PSC genotypes. An increase in PSC was found when crossing SI × PSC parents, illustrating a threshold effect. PSC × PSC crosses (high × low, low × low) produced SI, low, and mid PSC I₁ individuals but did not show a heterotic effect, since the PSC parents had already surpassed the PSC threshold. Selfing high PSC parents, however, suggested different genetic control. Progeny and highest individual means behaved the same; 83% decreased and 17% remained the same for PSC levels. The drop in PSC indicated non-additive gene action. Thus, the PSC threshold with additive gene action holds when selection for higher PSC levels is being done from low and mid PSC parents, but once high PSC levels are obtained, non-additive gene action prevails.Abbreviations self pollinated - H _R Realized Heritability - PSC Pseudo-Self Compatibility - SC Self Compatibility - SI Self Incompatibility     

不同土地利用方式对高原喀斯特洼地土壤主要特性的影响

[目的]研究不同土地利用方式对高原喀斯特洼地土壤主要特性的影响。[方法]通过1∶10000地形图对特定高原喀斯特洼地不同土地利用方式进行划分与归类,分层取样分析土壤剖面特性、理化性质变化。[结果]土层（A＋B层）厚度的变化趋势为坡耕（退耕林）地〉天然林地〉人工林地〉灌木林地,土壤剖面特征、水源涵养、颗粒组成、土壤肥力与肥力有效性的相关指标在不同利用方式间发生了相似或相异的规律性变化。土壤综合质量指数的变化趋势为耕地〉退耕林地〉坡耕地、天然林地〉人工林地。耕地土壤综合质量最高,是自然成土和人为经营的结果。3～5年的退耕林地土壤综合质量高于坡耕地,表明造林措施是改善喀斯特洼地坡耕地土壤质量的有效手段。天然林土壤综合质量高于人工林地,这为利用＂近自然经营＂技术改善喀斯特洼地土壤质量提供了依据。[结论]该研究可为喀斯特地区石漠化的生物治理、土壤质量演化的生物学控制技术提供理论依据。     

喀斯特峰丛洼地小流域表层土壤养分的空间异质性

为研究喀斯特峰丛洼地小流域土壤化学性质的空间变异性,基于规则网格取样(80m×80m),测定了典型喀斯特峰丛洼地木连喀斯特小流域163个表层(0cm~20cm)土壤样点基本养分全氮TN(total nitrogen)、全磷TP(total phosphorus)、全钾TK(total potassium)、有效氮AN(available nitrogen)、速效磷AP(available phosphorus)、速效钾AK(available potassium)、有机质SOM(soil organic matter)含量和pH值,并利用经典统计学和地统计方法进行了空间变异特征分析。结果表明:研究区土壤这8种指标数值的差异及变异系数均较大,各项土壤养分指标的变异程度依次为TK >AP >AN >TN >SOM >AK >TP >pH。不同养分指标具有不同的空间结构和最佳拟合模型,除TK和pH呈现强烈空间自相关、变程较短、空间依赖性较强外,其余6种指标(TN、TP、AN、AP、AK、SOM)均呈中等空间自相关,变程较长,空间连续性较好。Kriging等值线图直观、清晰的反映了研究区土壤养分空间格局。TN、AN、SOM的Kriging等值线图相似并且它们的空间分布趋势与pH正好相反,TP和AP的Kriging等值线图相似,TK和AK的Kriging等值线图相似。除pH外,木连喀斯特小流域养分空间格局可概括为:东边高,西边低,南边高,北边低,洼地高,坡地低。人为干扰和自然条件(地形、地貌、植被、裸岩率、坡度、坡向)是土壤养分空间异质性的主要影响因素。     

蛤仔白斑马品系的家系选择及近交效应研究

以2011年通过双列杂交方式建立的18个蛤仔Ruditapes philippinarum白斑马正反交家系为基础材料,从中筛选出5个具有优良性状的家系子一代,建立全同胞家系子二代近交家系A2、B2 C2、D2、E2,并设立对照组O2(混交家系),比较各近交家系的生长和存活情况,计算近交衰退率,并对各家系进行了综合评价.结果表明:幼虫期,除3日龄外,对照组O2蛤仔的壳长普遍略大于其他家系,但近交衰退现象不明显;A2家系的存活率最高,其他家系的近交衰退率为4.56％～36.27％.稚贝期,各家系生长速度差异很大,各家系近交衰退明显,除C2家系外,各家系的近交衰退率为0.54％～20.00％; A2家系存活率仍然最高,C2家系存活率略高于对照组O2,B2、D2和E2家系的近交衰退率分别为27.86％、12.18％和10.92％.综合分析表明,蛤仔白斑马近交家系中C2为生长快的家系,A2为存活率高的家系.     

膜府系统的病理特征初探——中医膜府系统学说之三

膜府的病理特征是受纳邪气,转输病邪,气机怫郁,阴阳失调,渗灌障碍则津停血瘀,渗泄无度则耗伤气血津液,久病入膜则气滞血瘀而成痼疾,虚实夹杂,变化多端。     

Ⅱ型糖尿病老年人抑郁与HbA1c水平关系的研究

目的了解Ⅱ型糖尿病老年人抑郁现状及HbA1c水平,探讨Ⅱ型糖尿病老年人抑郁与HbA1c水平的关系.方法采用便利抽样法对Ⅱ型糖尿病老年人共316名进行抑郁问卷调查,并对其进行相关生化检查.结果 47.5%的Ⅱ型糖尿病老年人糖化血红蛋白（HbA1c）呈高值,且抑郁检出率为25.6%;抑郁组与非抑郁组Ⅱ型糖尿病老人FPG,2h-PG及HbA1c等生化指标存在差异（P〈0.01）;多因素Logistic回归分析结果表明：民族、并发症、抑郁是影响HbA1c水平的重要因素.结论Ⅱ型糖尿病老年人抑郁症状普遍存在,抑郁患者血糖控制能力较差,临床医生应注重糖尿病老年人的心理治疗,帮助患者及早摆脱不良心理,恢复自信,降低HbA1c水平,有效控制血糖.     

文拉法新与氯米帕明治疗抑郁症的Meta分析

目的：比较文拉法新与氯米帕明治疗抑郁症的疗效及副作用。方法：检索中国生物医学文献数据库（CBM）、中国期刊全文数据库（CNKI）及中文科技期刊全文数据库（VIP）,时间截至2010年5月31日。纳入文拉法新与氯米帕明比较治疗抑郁症病人的随机对照试验。结果：共纳入16个随机对照试验,研究对象1158例。Meta分析结果显示：文拉法新与氯米帕明相比治疗病人的有效率较高［OR=1.34,95%CI(1.02,1.75)］,两组病人治疗后痊愈率无统计学差异［OR=1.24,95%CI(0.97,1.58)］,治疗后两组病人头晕、头痛、口干、便秘发生率差异有统计学意义,［OR=0.30,95%CI(0.19,0.49)］、［OR=0.60,95%CI(0.38,0.96)］、［OR=0.16,95%CI(0.12,0.23)］、［OR=0.21,95%CI(0.14,0.32)］。恶心呕吐发生率无统计学意义［OR=0.89,95%CI(0.56,1.41)］。结论：文拉法新治疗抑郁症有效率高于氯米帕明,头晕、头痛、口干、便秘发生率低于氯米帕明。     

围绝经期抑郁症三种治疗方法的比较

目的 :观察三种治疗方法对围绝经期抑郁症患者的疗效。方法 :对围绝经期患者出现焦虑与抑郁情况进行评估 ,行SDS评分。将确诊为抑郁症的 12 0例随机分为 3组 :激素连续性序贯治疗组 (A组 )、心理治疗加氟西汀治疗组(B组 )、心理治疗加氟西汀及激素连续序贯治疗组 (C组 )各 4 0例 ,疗程均为 3个月。治疗 3个月后行HDRS评分 ,了解治愈情况。结果 :C组疗效明显优于A、B组 ,均差异有显著性 (P <0 .0 1,0 .0 5 ) ;A组和B组的疗效比较则差异无显著性 (P>0 .0 5 )。结论 :采用C组治疗方法对围经期抑郁症患者疗效良好且疗效肯定 ,值得推广。     

The Role of epistasis in controlling seed yield and other agronomic traits in an Andean × Mesoamerican cross of common bean (Phaseolus vulgaris L.)

Epistasis is a pervasive phenomenon in biology. Nevertheless, attempts at identifying epistatic interactions with quantitative trait loci (QTL) analyses have yielded inconsistent results. In this study, we attempt to determine the genetic control of outbreeding depression and the possible role of epistasis following a wide cross in common bean (Phaseolus vulgaris L.). A recombinant inbred population, derived from a cross between Andean and Mesoamerican common bean cultivars, was evaluated in two markedly contrasting environments. A low-density linkage map based on AFLPs was used to locate QTLs for the number of days to maturity, average daily biomass and seed yield accumulation, and harvest index. Both independently acting and digenic epistatic QTLs of similar magnitude were identified. A majority of the loci involved in these epistatic interactions did not have an independent effect. Although we did find evidence for strong epistatic control of the traits investigated, we also found, in contrast to other recent studies, that there was no evidence for a bias toward coadapted gene complexes at the level of digenic epistasis. We discuss these results in relation to the role of epistasis in the evolutionary history of the species and methodological difficulties in detecting epistasis. This revised version was published online in July 2006 with corrections to the Cover Date.     

Comparison of homozygous and heterozygous self-compatible seedlings in an almond breeding programme

Homozygous self-compatible almond cultivars have not been reported. It is unclear if they are more inferior than heterozygotes or simply have not yet been detected. To investigate if homozygous individual are generally inferior, the self-compatibility genotype, homozygous or heterozygous, was determined by stylar ribonuclease assay in a population of 241 almond trees obtained by self-fertilisation of self-compatible selections. The resulting zymograms showed that 129 of the seedlings were homozygous and 112 heterozygous. For three years the differences observed between these two classes of self-compatible individuals were analysed with respect to 16 agronomic characteristics. In general, there were no important differences between the two classes. Both showed a low degree of productivity, probably as a result of their inbred origin. Some selected homozygous individuals were used in crosses, which were planned so as to ensure the self-compatibility of 100% of the descendants and to eliminate the laborious task of testing the seedlings for self-compatibility. This revised version was published online in August 2006 with corrections to the Cover Date.