白桦幼苗株高和地径的遗传分析

以来自不同种源的6个白桦(Betula platyphylla)优良树为亲本,按Griffing方法4的不完全双列杂交设计进行人工控制受粉,获得F1杂种.对白桦幼苗的株高和地径一般配合力(GCA)和特殊配合力(SCA)分析表明,白桦幼苗的株高和地径同时受加性和非加性效应控制;同一亲本不同性状的GCA差异较大,同一性状在不同亲本间的GCA差异也比较大,在6个亲本中来自清源的Q2的株高和地径GCA最高,来自帽儿山种源的M2次之;同一性状不同组合和同一组合不同性状的SCA均有较大差异,来自芬兰种源和来自清源种源的2个亲本组合E8xQ1的株高和地径的特殊配合力最高;幼苗株高和地径的一般遗传力和特殊遗传力均在60%以上,可以对株高和地径这两个性状进行早期选择.     

谷子两系杂交组合的杂种优势及亲本配合力分析

为了解谷子两系杂种优势的亲本配合力遗传基础,本研究利用5个不育系和8个恢复系按NCII不完全双列杂交组配40份(5×8)杂种F₁,对11个谷子主要农艺性状的杂种优势及配合力进行分析。结果表明,谷子两系杂交组合在穗长、穗粗、千粒重、分蘖性、单穗重、单穗粒重和产量7个性状中存在广泛的超亲优势,但除千粒重外,其余性状的显著超亲组合数较少。杂交组合的单穗重和单穗粒重与产量极显著相关,且相关系数较高。对优异亲本进行筛选发现,A2和R3为一般配合力(GCA)较好亲本,A1、A2为GCA产量效应优异亲本,A1×R3、A2×R8、A3×R5、A3×R7和A5×R1为产量特殊配合力(SCA)效应较优组合。对产量强优势组合的配合力进行分析,发现优异的两系杂交组合中包含至少1个GCA较高的亲本或拥有较高的SCA。本研究结果为谷子优异两系杂交组合的亲本选配提供了一定的理论依据。     

杂交水稻部分品质性状的配合力研究

为了解决杂交水稻主要品质性状的选育问题，运用25个早籼稻组合按北卡罗莱纳Ⅱ(NCⅡ)设计进行了配合力的研究，结果表明：精米长、精米宽、精米形状、胶稠度、糊化温度、直链淀粉含量、蛋白质含量等7个性状受不育系的一般配合力效应和组合特殊配合力效应的影响达显著或极显著水平，受恢复系一般配合力效应的影响未达显著水平，其广义遗传力和狭义遗传力都较高，因此在育种中要特别注意不育系本身的特点。垩白级别、糊化温度的狭义遗传力较小并受特殊配合力影响较大，在世代传递中的稳定性是较差的，因而在育种时要特别考虑双亲的表现值。     

甜玉米自交系可溶性糖含量配合力及遗传参数分析

以6份可溶性糖含量不同的甜玉米自交系为材料,按GriffingⅣ杂交试验设计方法组配15个杂交组合,对甜玉米自交系可溶性糖含量进行配合力分析,并估算群体遗传参数。研究结果表明,6个自交系一般配合力(GCA)效应差异显著,自交系Su138 GCA效应为最大正效应,其次是Su119、Su579和Su528;Su325和Su311表现负的GCA效应。结合杂交组合实际可溶性糖含量与特殊配合力(SCA)效应进行分析,Su138所组配的各组合可溶性糖含量表现和SCA效应均较好。群体遗传参数分析结果表明,该性状广义遗传力为78.0%,性状遗传主要为加性效应,存在一定的非加性效应,环境条件对性状表现影响较大。     

小麦GMP含量的配合力分析

选用6个小麦亲本材料.按照Griffing方法Ⅱ组配了一套双列杂交组合,研究了谷蛋白大聚合体(GMP)含量的配合力和遗传力.结果表明,谷蛋白大聚合体的遗传受加性基因和非加性基因的共同控制,以加性效应为主.一般配合力效应值和亲本的GMP含量呈极显著正相关,二者的排列顺序呈现完全一致的趋势.大部分杂交组合的特殊配合力效应值为负值,GMP含量遗传力很高,可通过常规育种提高杂交种的GMP含量.     

玉米花培纯系的配合力研究

采用完全双列杂交的统计分析方法,对2个玉米花培纯系和4个普通自交系的5个性状,进行了一般配合力和特殊配合力的分析.结果表明,6个纯系5个性状的一般配合力和特殊配合力有差异.花培纯系双白的单株粒重和穗长两性状的一般配合力最高,且其特殊配合力方差最小,说明该纯系能稳定地把高产、穗长的特性遗传给后代.339-2的单株粒重性状的一般配合力与南60-1相当,但其特殊配合力方差最大,与南60-1组配,可获得强优势组合.     

小麦淀粉品质性状配合力效应及遗传分析

选用9个冬小麦品种,按NCⅡ不完全双列杂交设计,对淀粉主要品质性状进行了配合力及相关分析。结果表明：淀粉品质性状一般配合力和特殊配合力方差均达显著或者极显著水平,综合考虑亲本各性状一般配合力相对效应,中优9507、济麦20、偃展4110适合做面条和馒头小麦品质育种优良亲本;藁麦6/偃展4110和扬麦16/偃展4110,一般配合力效应和特殊配合力效应表现优秀,总的配合力效应表现也最好,利用价值大,为优良组合。直链淀粉的遗传主要是基因的累加效应,粘度性状、总淀粉、蛋白质品质性状的遗传以加性效应为主,非加性效应为辅;峰值粘度、低谷粘度、最终粘度狭义遗传力达74.47%以上,宜在早代进行选择;直链淀粉、膨胀势在50%以下,高世代选择效果较好。峰值粘度、低谷粘度、最终粘度与支链淀粉、总淀粉、膨胀势呈极显著的遗传负相关,而与直链淀粉、降落数值均呈显著或极显著遗传正相关,可以完全同向选择。     

玉米苗期根系对氮胁迫反应的配合力分析

研究利用7个玉米自交系,采用NC-Ⅱ设计,分析了玉米苗期根系性状对氮胁迫反应的配合力及遗传参数变化。结果表明,在2个氮水平下,玉米苗期根系性状的一般配合力、特殊配合力都存在显著的基因型差异,而且不同的基因型在氮胁迫下的反应也不尽相同。高氮下,根系性状除轴根长以外均以非加性遗传为主;氮胁迫下,除轴根数以外的根系性状以加性遗传为主。2个氮水平下,根干重、总根长和侧根长的广义遗传力均较高;与高氮处理相比,在低氮胁迫下,根系性状的广义遗传力表现为下降趋势,根干重、总根长和侧根长的狭义遗传力有上升的趋势。     

籼型三系杂交稻稻米中重金属镉含量的杂种负优势效应及配合力、遗传力分析

本文采用5 个不育系与6 个恢复系进行不完全双列杂交。从配制的杂交组合中选择30 个生育期基本一致的组合, 研究籼型杂交稻稻米中重金属Cd 含量的杂种优势表现及配合力、遗传力。结果表明: 稻米中Cd 含量有明显的杂种负优势效应; 不育系和恢复系稻米中Cd 含量的一般配合力效应及二者的特殊配合力效应均达极显著水平, 说明低Cd 含量组合的选育中双亲的遗传改良和组合的评价筛选都很重要。Cd 含量的广义遗传力与狭义遗传力均较高、且相差较小, 分别为97.73%和80.10%, 说明稻米Cd 含量以基因加性作用为主, 亲本改良在早期世代选择的效果较好。     

不同甘蓝型油菜品种磷素籽粒生产效率的配合力及遗传参数分析

以22个甘蓝型油菜品种(系)为亲本(17个母本,5个父本),按NCⅡ设计配成175=85个F1,在不施磷肥（CK）和施P2O5 150 kg/hm2（P150）两个处理条件下,对不同品系油菜磷素籽粒生产效率进行配合力和遗传参数分析。结果表明, 磷素籽粒生产效率（PUEs）杂交组合平均值在P150和CK处理中分别比亲本平均值高6.41%和7.64%。离中亲优势的正向组合数明显多于负向组合数,超亲优势的正向组合数（超高亲）明显多于负向组合数（超低亲）,表明PUEs存在杂种优势。PUEs的遗传参数在P150处理和CK处理中一般配合力方差相对较小,特殊配合力相对较大,PUEs遗传以非加性效应（显性效应及上位性效应）为主。在两个肥力水平下,品系9（ZS-3）的一般配合力较高,620（SY07湘05499）、 1320（NY-14湘05499）、 1421（湘05487YY-7）三个组合的特殊配合力较高。     

Genetic analysis of resistance to Fusarium wilt disease,yield and yield-related traits of pigeonpea (Cajanus Cajan (L.) Millsp.)

ABSTRACT

Understanding the genetic control of Fusarium wilt resistance is crucial in pigeonpea breeding programme. This study aimed to study the gene action controlling Fusarium wilt resistance, yield and yield components and select promising crosses possessing resistance to Fusarium wilt along with important agronomic yield traits. Six lines were crossed with four testers in a line x tester mating design. For Fusarium wilt reaction, F₁’s progenies were evaluated in a sick field having inoculums of Fusarium wilt at one location for two seasons and in a pot as well. The F₁’s and parents were evaluated for yield and yield components at two locations for two seasons using a row-column design with two replications. Results indicated that parents and crosses had highly significantly difference for yield and important agronomic traits. General combining ability (GCA) effects of lines and testers were also significant. Specific combining ability (SCA) was also significant for some crosses. Non-additive gene action was more important than additive gene action except for days to maturity and plant height. Crosses ICEAP 00932?×?TZA 2439 and ICEAP 00932?×?TZA 197 displayed small effects of SCA for Fusarium wilt and large SCA for most of yield traits and should be used for integrated disease management.     

蚕豆6×6双列杂交子代主要性状的遗传效应分析

为提高蚕豆优势组合的选配效率,以6个蚕豆材料(P1~P6)为亲本,采用Griffing完全双列杂交配制30个组合,分析亲本和F₁的9个主要农艺性状的杂种优势、配合力和遗传力。结果表明,蚕豆产量相关农艺性状的杂种优势明显,分枝数、单株荚数、单株粒数、每荚粒数、百粒重和单株产量的超亲优势为正值,株高、始荚高和主茎节数的超亲优势为负值。配合力效应分析表明,P1和P2为选育大粒高产的优良亲本,P1×P2和P4×P6符合高产的育种目标,P2×P5和P2×P6符合大粒的育种目标;遗传力分析表明,百粒重、每荚粒数和单株粒数的广义遗传力和狭义遗传力均较高,可以相对稳定地遗传给后代,且这3个性状主要受加性效应控制,适宜进行早代选择,其他性状主要受非加性效应影响;主要性状与单株产量的相关分析表明,蚕豆育种应将单株荚数和单株粒数作为重点目标;通径分析表明,在育种过程中应重点关注分枝数、株高、百粒重、每荚粒数等农艺性状。本研究为蚕豆育种进程中的亲本选配和后代选择提供了一定的理论依据。     

Use of GGEbiplot methodology and Griffing's diallel method for genetic analysis of partial resistance to phoma black stem disease in sunflower

Abstract

The objectives of the present study were to estimate the general combining ability (GCA) and specific combining ability (SCA) for partial resistance to phoma black stem and to identify the most promising combination for the selection of improved breeding lines. The response of five parental genotypes and their F1 hybrids to a phoma black stem isolate (MA6) were evaluated in a diallel programme under controlled growth chamber conditions. Significant GCA and SCA indicate that both additive and non-additive gene effects contributed in the inheritance of partial resistance to phoma black stem, however, the Baker ratio showed that the additive genetic effects were more important than nonadditive ones. It is recommended that the GGEbiplot methodology could be an excellent tool for visualizing entry by tester (diallel) data. By using this technique to analyse black stem severity data, interaction among the sunflower genotypes in providing partial resistance to phoma black stem was clearly identified. Based on GGEbiplot presentation and Griffing's diallel analysis, the mutant line ‘M6-54-1’ showed the largest GCA, indicating contribution towards partial resistance, and the genotype B454/03 presented the smallest GCA, indicating contribution towards susceptibility. Our results show that the F1 hybrids ‘SDR18×B454/03’ and ‘M6-54-1×B454/03’ showing heterosis for partial resistance to phoma black stem come from the crosses between a susceptible genotype ‘B454/03’ and two partially resistant genotypes (SDR18 and M6-54-1), originated from different breeding programmes. We conclude therefore that these genotypes possess at least some different resistance genes, which were expressed in the hybrids and led to the observed effects.     

Diallel Analysis of Wheat Parents and Their F2 Progenies under Medium and Low Level of Available N in Soil

ABSTRACT

Due to high production cost and prevention of environmental pollution, it is important to reduce the amount of nitrogen (N) fertilizer used on wheat (Triticum aestivum L.). The aim of this study was to evaluate N use of 6 × 6 diallel wheat F₂ progenies and parental lines at low (N0, no N fertilizer) and high (N+, 160 kg N ha^{? 1}) N levels. Significant differences were found between N+ and N0 application in grain N content, grain N yield, N use efficiency for grain N yield (NUEgn), and N use efficiency for grain yield (NUEgy). The cultivar ‘84ÇZT04’ showed positive and high general combining ability (GCA) effects for all traits at low N level. Also, it was the best combiner for all traits at both N levels. The cultivar ‘Genç 99’ was the best parent for GCA effects for grain yield and NUEgy. Hybrids ‘Genç 99 × 84ÇZT04’ and ‘84ÇZT04 × Weaver’ showed positive specific combining ability (SCA) effects for all investigated traits at low and high N levels. Variety ‘84ÇZT04 × Apogee’ had the best SCA effects for all traits at low N level. Overall, the data suggest that it is probable to select promising lines suitable for low N conditions by the crossing of high N use efficient parents.     

Maize (Zea mays L.) genetic factors for preventing fumonisin contamination

Fusarium moniliforme and Fusarium proliferatum are the most frequently isolated fungi from maize (Zea mays L.) in Spain. Both Fusarium species produce toxins potentially dangerous for animals and humans, the fumonisins being the most significant of those toxins. White maize is preferred for human consumption, and extra care should be taken to avoid kernel mycotoxin contamination. The objectives of this study were to identify and quantify kernel infection by Fusarium spp. and contamination by fumonisin on white maize hybrids, to search for white maize sources of resistance to infection by Fusarium spp. and mycotoxin contamination, and to preliminarily study the genetics involved in such resistances. Ten F(1) single crosses derived from a diallel mating design among five white maize inbreds were evaluated in a randomized complete block design with three replications in 2002 at two locations. Fusarium verticilloides and F. proliferatum were detected on kernels of white maize hybrids cultivated in northwestern Spain. No differences in fungal infection were found among maize genotypes, but differences in fumonisin contamination were significant and could be related, in part, to differences in husk tightness. Among the genotypes studied, general combining ability (GCA) effects were the most important for resistance to fumonisin contamination. Inbreds EP10 and EC22 showed the most favorable GCA effects for husk tightness and fumonisin content, and the cross between them, EP10 x EC22, had the most favorable specific combining ability (SCA) effect for husk tightness. Inbreds EP10 and EC22 showed favorable GCA effects for fumonisin contamination and husk tightness, and the cross EP10 x EC22 was the only one with an average fumonisin level below 1 mug/g. Although this should be confirmed with more extensive studies, white maize inbreds developed from white maize landraces could be sources of resistance to fumonisin contamination.     

核辐射创造的高配合力水稻种质扬稻6号的应用

辐射诱变育成的水稻新品种扬稻6号在每穗总粒数、每穗实粒数、结实率、千粒重、籽粒充实度、单株产量等产量构成性状上的一般配合力和特殊配合力显著高于其它参试恢复系,对“两系”不育系和“三系”红莲型不育系具有配制出超高产杂交稻组合的特殊配合能力,其丰产、优质、多抗性能推进了以其作恢复系所配制杂交稻组合,及以其作亲本选育常规水稻品种和恢复系“水涨船高”的发展。