普通玉米3个籽粒品质性状的配合力分析

以10个普通玉米自交系及其90个杂交组合在北京和山西2个地点的试验数据,分析了蛋白质、淀粉和油分含量的配合力效应。结果表明：(1) 各性状的一般配合力(GCA和特殊配合力(SCA) 均方极显著,且GCA均方大于SCA均方,说明它们在遗传上主要受加性基因效应的影响。(2) 杂交种的3个品质性状与亲本GCA平均值和SCA极显著正相关,但与亲本GCA均值间的相关性相对较强,其相关系数(r)分别为0.708**(蛋白质)、0.756**(淀粉)和0.772**(油分),表明提高亲本GCA对改良杂交种品质具有更大的作用。(3) 自交系BT1和E28的蛋白质含量GCA较高,掖478、昌7-2、掖107和48-2的淀粉含量GCA较高,E28、黄C和P138的油分含量GCA较高。     

普通小麦籽粒DON含量的配合力分析

为了选育抗赤霉病且籽粒毒素含量低的小麦品种以减轻赤霉病危害,在对我国南方麦区地方品种进行赤霉病抗性鉴定的基础上,选用8个籽粒中脱氧雪腐镰刀菌烯醇（deoxynivalenol, DON）含量水平不同的小麦品种作亲本,按8×8半双列杂交配制28个杂交组合,以接种后成熟籽粒中DON含量、病小穗数、病小穗率和病粒率为指标,进行赤霉病抗性、一般配合力（GCA）和特殊配合力（SCA）遗传分析,以及不同鉴定指标间比较和相关性分析。结果表明,8个品种中籽粒DON含量以苏麦3号最低(0.5715 mg kg^-1),Alondra’s最高(13.5560 mg kg^-1),各组合F1的籽粒DON含量均低于感病品种Alondra’s。品种间GCA和SCA存在显著差异,籽粒DON含量以加性效应为主,存在部分显性效应。苏麦3号、望水白和翻山小麦表现出较好的一般配合力效应。以苏麦3号为亲本的5个组合、望水白为亲本的4个组合特殊配合力效应较大。扬麦158一般配合力效应较小,但有4个组合表现较好的特殊配合力效应。籽粒DON含量和病小穗数、病小穗率、病粒率呈极显著的正相关关系。感病品种Alondra’s和绵阳8545的各个抗性鉴定指标的一般配合力在8个品种的排序中表现一致,抗病品种各个抗性指标的一般配合力在8个参试材料间的排序有所差异。DON含量的狭义遗传力为74.54%,因此以抗DON积累为指标的赤霉病抗性育种,可以在早期世代进行选择。     

杂交水稻主要米质性状的配合力分析——Ⅰ.直链淀粉含量

选取杂交水稻4个不育系和9个恢复系按不完全双列杂交配组得到36个杂交组合,测定了108个小区(3次重复)稻米的直链淀粉含量,旨在分析杂交水稻亲本直链淀粉含量的一般配合力(gca)和组合的特殊配合力(sca),以期为优质杂交稻米亲本选育和组合选配提供一定的参考依据。结果表明:对F_1稻米直链淀粉含量的影响,亲本间和组合间均存在显著或极显著差异。亲本不育系珍汕97A和恢复系明恢63的gca最好,而sca最好的是汕优63。gca低(高)的两亲本,其F_1稻米的直链淀粉含量一般也低(高)。但由于亲本间存在相互作用,这一现象并不存在于所有组合。在优质杂交稻米亲本选育和组合选配过程中,既要注意亲本(特别是恢复系)本身的特性和一般配合力效应,也要考虑组合的特殊配合力效应。     

杂交水稻品质性状的配合力及遗传力研究

为了给杂交水稻主要品质性状的选育提供依据,本研究以三系野败型杂交水稻的恢复系和微核心种质构成的112份优异品种为父本,以四个两系不育系和一个三系不育系为母本,按照不完全双列杂交设计配制了560个组合,分析各组合及其亲本的12个品质性状的配合力与遗传力。结果显示考查的12个品质性状的一般配合力(general combining ability,GCA)和特殊配合力(specific combining ability,SCA)均存在极显著差异,说明各性状受基因加性效应和非加性效应的共同作用,其中在直链淀粉含量、粒长宽比、粒长、粒宽、垩白粒率及垩白度等性状上基因的加性效应占主导地位;在蛋白质含量、糙米率、精米率、整精米率、透明度及碱消值级等性状上则以基因的非加性效应为主。同一组合在不同性状间及同一亲本所配的不同组合的SCA差异较大,最高或最低SCA的组合可来自不同GCA的亲本组合类型,表明亲本GCA与SCA没有固定联系。母本的GCA方差贡献率为0.76%~26.21%,父本的GCA方差贡献率为17.47%~81.94%,在各性状上母本GCA方差贡献率均比父本GCA方差贡献率小,说明各性状受母本(不育系)的影响均较小。直链淀粉含量、粒长宽比、粒长、粒宽、垩白粒率及垩白度的狭义遗传力较高,均在50%以上,可在低世代进行选择。     

棉花复合杂交育成亲本主要产量性状的杂种优势及配合力分析

为测定利用复合杂交育成的5个亲本的育种应用潜力,将5个亲本与4个推广品种采用不完全双列杂交设计配制20个组合,对组合的产量及相关性状的杂种优势进行分析,并对5个亲本的产量及相关性状进行配合力分析.结果:铃数对产量的贡献最大;A1亲本在铃数,A2亲本在衣分,A3亲本在铃重,A 5亲本在铃重、衣分性状上一般配合力(GCA)为正,A 5亲本是一个较理想的亲本;具有较高特殊配合力效应(SCA)的组合有A5×B3、A2×B2、A3×B1.结论:利用复合杂交培育高配合力亲本是可行的;但不同来源的亲本在同一性状,同一亲本的不同性状间一般配合力(GCA)是不同的;同一性状的不同组合间,同一组合的不同性状间特殊配合力(SCA)效应也都存在大小或方向上的差异.     

胡麻17份亲本及组合主要性状的配合力分析

为了筛选胡麻优质品系作为杂交亲本配置组合,以求进一步在胡麻产量和品质方面有所突破,以本单位新培育的8个胡麻品系作为母本,与9个成熟品种进行组配,共配制72个杂交组合,旨在测定亲本的一般配合力(GCA)和特殊配合力(SCA)。结果表明,CP2205在和产量密切相关的单株果数方面GCA表现突出,在千粒重和每果粒数方面也有正向表现;品质方面,CP2205在含油率、亚油酸、亚麻酸等重要方面GCA均表现较好,可作为重点品系进行组配。配置组合时可选用每果粒数、蛋白质和木酚素GCA值较高的品种来进行组配,从而提升后代材料的产量和品质。09-3-11在亚麻酸和亚油酸方面具有较高GCA效应,但在单株果数和每果粒数方面效应较低,组配时应选择这两方面GCA表现较为突出的品种作为亲本,可更容易选出优良后代。     

中国南瓜β-胡萝卜素含量配合力的研究

以16个具有代表性的中国南瓜自交系及其按Griffing双列杂交方法Ⅳ组配成的120个杂交组合为材料,对中国南瓜β-胡萝卜素含量的配合力进行了系统的研究,旨在了解不同南瓜自交系β-胡萝卜素含量的配合力特点。结果表明：在16个南瓜自交系中,从上海黄狼南瓜中选出的自交系‘百泉10’的一般配合力最大,其次是,‘百泉5’（来源于广东）,‘百泉4’（来源于黑龙江）。最小的是‘百泉2’（来源于北京）。在120个杂交组合中,特殊配合力最大的是‘百泉9’（来源于河南）ב百泉10’（来源于上海）,其次是‘百泉7’（来源于河南）ב百泉15’（来源于北京）、‘百泉4’（来源于黑龙江）ב百泉12’（来源于海南）,最低的是‘百泉1’（来源于湖南）ב百泉11’（来源于江西）。因此不同来源的南瓜自交系间一般配合力差异很大。自交系间地理差异越大,其间的特殊配合力往往越高。     

番茄晚疫病抗性遗传研究

通过对4份亲本材料完全双列杂交后代进行方差分析、配合力分析,对番茄晚疫病抗性遗传规律进行了研究,结果表明:一般配合力和特殊配合力均达到极显著水平,但一般配合力较大,其二者比值为(GCA/SCA)18.7,说明番茄对晚疫病的抗性以加性效应为主;利用Haym an双列杂交法,对各亲本和杂交组合后代间的方差(Vr)、协方差(W r)进行回归分析,抗性符合"加性-显性"模型,遗传效应中存在加性效应和显性效应,广义遗传力为96.8%,狭义遗传力85.6%,进一步说明了在番茄抗晚疫病的遗传中以加性效应为主。     

高羊茅对重金属镉的抗性分析

为了解不同高羊茅品种对重金属镉的抗性差异,探讨其修复镉污染土壤的作用,通过形态和生理指标测定,对不同浓度镉胁迫前后的高羊茅品种形态和生理指标进行比较分析。结果表明：低浓度氯化镉胁迫下,高羊茅品种‘猎狗’的茎叶鲜重、最大根长、根鲜重、叶绿素含量等指标呈增长趋势,到达一定阈值后则受到抑制;相对电导率、MDA含量、脯氨酸含量则随镉浓度的增大而持续升高;根系活力则表现为随镉浓度的升高而逐渐下降。进一步利用50 mg/L的氯化镉胁迫处理9个高羊茅品种,对茎叶鲜重、根鲜重、最大根长等形态指标的变化情况进行分析评估。试验结果显示,多数品种的抗性与根部性状的表现更为密切;综合抗性由强到弱的排列顺序为：‘交战Ⅱ’>‘毕加索’>‘猎狗’>‘杰作’>‘新秀’>‘碧翠A’>‘可奇思’>‘爱瑞’>‘达芬奇’。对于镉污染程度较高的土壤,可选择综合抗性较高的品种‘交战II’进行治理修复;对于镉污染程度较低的土壤,可选用抗性一般但地上部分生物量较高的品种‘新秀’。     

同品种香蕉外观品质和内在品质的比较研究

为解决如何评价不同品种香蕉品质优劣的问题,对广东省湛江市香蕉资源圃8个香蕉品种的果实外观品质进行调查评价,并分析测定果实的糖、有机酸、VC、单宁、淀粉等的含量。结果表明,香蕉不同品种之间的外观品质存在显著差异,‘威廉斯’、‘巴西诱变’、‘北大矮蕉2号’外观品质较优;所测定的香蕉不同品种间各内在品质指标有显著差异,淀粉、VC、单宁含量各品种间变化幅度较大,可溶性糖、有机酸含量不同品种间变化幅度较小。综合分析可知,‘威廉斯’、‘巴西诱变’、‘北大矮蕉2号’的品质较优。     

粳型两系杂交稻品质性状的遗传分析

选择有代表性的11个优良粳型两系杂交稻亲本,包括6个光敏核不育系和5个粳稻恢复系,采用p×q不完全双列杂交模式对4个品质性状的配合力进行分析并估算其遗传参数.结果表明,4个品质性状的一般配合力(GCA)和特殊配合力(SCA)均达到了显著或极显著水平.在垩白度、直链淀粉含量性状上,以加性效应占主导地位;在胶稠度两性状上则以非加性效应为主,而在整精米率上加性效应和非加性效应的作用相当.     

高粱酿造品质性状配合力分析

为了科学、准确地评价酿造高粱主干亲本系,为进一步利用材料、提高品质育种效率提供依据,选用3个不育系,5个恢复系,按不完全双列杂交法组配15个杂交组合,对蛋白质、脂肪、总淀粉、单宁4个酿造品质性状进行了配合力分析。结果表明,3个不育系中‘辽3401A’蛋白质、脂肪、单宁含量的一般配合力均较高,‘泸45A’总淀粉含量的一般配合力较高。5个恢复系中,741324单宁含量的一般配合力较高,R111脂肪、单宁含量的一般配合力较高,038R总淀粉含量的一般配合力较高,C52R-11总淀粉含量的一般配合力较高。‘961541/0-30红粒’蛋白质、脂肪含量的一般配合力较高。加性方差与基因型方差的比值依次是蛋白质 > 总淀粉 > 脂肪 > 单宁。     

Genetic analysis of rapeseed self-incompatibility lines reveals significant heterosis of different patterns for yield and oil content traits

Self‐incompatibility is one of the most effective approaches to utilizing heterosis in oilseed rape around the world. To evaluate the heterosis of double low self‐incompatibility, the possibility of combining seed yield and oil content, and the genetic effects of parents on their hybrid progenies, a 2‐year field trial using a 3 × 22 NC II mating design was conducted during the 1999‐2001 growing seasons in Wuhan, China. Significant differences in seed yield per plant and seed oil content were observed among the F1 hybrids and between F1 progenies and their parents. However, the heterosis for seed yield per plant was much greater than that for seed oil content. Mid‐parent heterosis and high‐parent heterosis of seed yield per plant ranged from 5.50 to 64.11% and from –2.81 to 46.02%, while those of seed oil content ranged from –1.55 to 7.44% and –3.61 to 6.55%, respectively. Non‐additive genetic effects were a major mechanism that accounted for the yield heterosis in addition to additive effects. In contrast, seed oil content heterosis was mainly dependent on an additive genetic effect. General combining ability (GCA) determined the stability of hybrid cultivars. In hybrid breeding, parental materials might be selected by the sum of GCAs and variances of special combining abilities (SCAs) of female and male parents for traits affected by both additive and non‐additive effects, and by the sum of GCAs of two parents for traits controlled mainly by additive effects. Primary branches and their siliques were the most important yield traits.     

几个高油与普通玉米自交系子粒品质性状的配合力分析

高油玉米杂交种由高油玉米自交系和普通玉米自交系杂交组配而成,高油玉米育种的核心仍然是杂种优势的利用。为了高油玉米育种的亲本选择和组合配制提供理论依据,以3份高油玉米新种质为父本,自选的4份普通自交系为母本,采用不完全双列杂交设计组配12个F1组合为供试材料,对其子粒油分、蛋白质和淀粉含量进行配合力分析。结果表明:不同的自交系,不同品质性状的配合力表现不同。XGY003、YZ141B、H195-2具有油分含量一般配合力较高的自交系。C279、YZ141B、H195-2自交系的蛋白质一般配合力较高。XGY003、XGY020、C279、H78-3自交系的淀粉一般配合力较高。一般配合力高的亲本,容易产生特殊配合力高的组合,但双亲的一般配合力较高的也不一定组合的特殊配合力就高。本试验没有发现3个品质性状一般配合力效应值都高的自交系。综合看来,3份高油玉米种质中XGY003油分含量一般配合力效应值较高,4份普通自交系中YZ141B、H195-2油分含量一般配合力效应值较高,这3个自交系在长治地区玉米育种中可作为高油玉米自交系加大利用,以选出油分含量较高的优势组合。C279、YZ141B、H195-2自交系的蛋白质一般配合力较高,XGY003、XGY020、C279、H78-3自交系的淀粉一般配合力较高,在以后玉米育种中可作为特用玉米自交系作进一步的改良和应用。     

Genetic analysis of mechanisms associated with inheritance of resistance to sheath rot of rice

Understanding genetic mechanisms controlling inheritance of disease resistance traits is essential in breeding investigations targeting development of resistant genotypes. Using North Carolina design II, 32 F₁ hybrids were generated by crossing eight susceptible to four resistant parents and submitted for field evaluation. The analysis of general and specific combining ability (GCA and SCA) indicated involvement of additive and non‐additive gene action controlling inheritance of horizontal resistance to sheath rot of rice. High GCA/SCA ratio and high heritability estimates revealed additive effects and were more predominant than none additive ones. The level of dominance indicated dominant genes was more important than recessive genes. Estimates of GCA and SCA analysis suggested that crop improvement programmes should be directed towards selection of superior parents or good combiners, emphasizing on GCA. As far as source of resistance is concerned, most promising genotypes were Cyicaro, Yunertian and Yunkeng. The predominance of additive genetic effects together with the relevance of dominant genes suggested possibilities of improving the resistance by introgression of resistance genes through recurrent selection coupled with phenotypic selection.     

Effects of cytoplasm on heterosis and combining ability for agronomic traits in rice (Oryza sativa L.)

Summary Effect of sterilizing (WA) cytoplasm on heterosis and combining ability for days to flowering, plant height and grain yield in rice was studied in 70 crosses and their reciprocals produced by 10 cytoplasmic male sterile (A), their maintainer (B) and seven restorer (R) lines following line x tester design. The materials consisting of 140 hybrids (70 A/R and their reciprocal 70 R/B) plus 17 parental lines (10 B + 7 R) were evaluated under six environments, created by growing in three fields with different fertilizer doses (0, 60, 120 kg N/ha) and 2 seasons (dry and wet) during 1986 at IRRI farm. Reciprocal cross effect (A/R vs R/B) were highly significant for all the three traits. Interaction of reciprocal cross effects with environments were also highly significant for yield and days to flowering. Cytoplasmic effect for yield, days to flowering and plant height were estimated by comparing A/R and R/B combination and testing the significance of difference with LSD value. In order to avoid confounding effect of spikelet sterility on yields, twenty crosses showing normal spikelet fertility were selected. Both positive and negative cytoplasmic effects were observed for the three traits. The effects were modified by environments, except for plant height. Heterosis for all three traits was also affected by cytoplasm, however, manifestation of cytoplasmic effects was higher for heterosis for days to flower than in heterosis for yield and plant height. Effect of cytoplasm was more pronounced on general combining ability effects of parents than specific combining ability effects of crosses. Among the parents two CMS lines A4 (IR54752A) and A8 (IR22107-113-3-3A) and two R lines: R2 (IR46) and R7 (IR9761-19-1) showed consistent positive effect of cytoplasm on general combining ability. These lines have given several good heterotic combinations. The study indicated the usefulness of evaluating diverse cytoplasmic sources in various nuclear genotypes bred for hybrid rice breeding program.     

陆地棉配合力与杂种优势、遗传距离的相关性分析

 用10个陆地棉亲本进行不完全双列杂交,共配置了45个组合,计算亲本的一般配合力（GCA）、特殊配合力(SCA)、杂种优势,并结合SSR标记研究了陆地棉亲本配合力与杂种优势、遗传距离之间的相关关系。配合力分析发现,10个亲本的一般配合力和特殊配合力存在显著或极显著差异。分析亲本配合力、杂种优势和遗传距离的相关性发现,子棉产量、皮棉产量、衣分的一般配合力和杂种优势呈显著或极显著相关,纤维长度、比强度、麦克隆值、株高、果枝数、单株铃数、铃重、子棉产量、皮棉产量、衣分的特殊配合力和杂种优势均呈极显著正相关,而与遗传距离相关均不显著。单株铃数、铃重、子棉产量、皮棉产量、衣分的杂种优势与遗传距离均为正向显著或极显著相关。在育种实践中这些显著或极显著相关的性状可能具有较高的改良潜力。     

Combining Ability of Doubled Haploids in Coffea canephora P.

Fifty-five doubled haploids (DH) of Coffea canephora were crossed with either heterozygous genotypes or DH in order to study their combining ability. Three agronomic trials were established. Marked hybrid vigour was observed for all characters analyzed including yield. Large differences were evident among top-crosses involving different DH produced from the same parental clone reflecting the high level of heterozygosity of clones. Factorial mating design analysis indicated that all genetic variance was attributable to additive effects in estimates of yield as well as plant height and leaf characteristics. The general combining ability variance component was also predominant for stem girth and susceptibility to leaf rust, although effects due to interaction were detected. Some hybrid combinations had yield comparable to standard clonal varieties. The implications of such results for breeding of Coffea canephora are discussed. Particularly, the development of F₁ hybrid varieties is envisaged.     

Genomic prediction of sunflower hybrid performance

Predicting single‐cross performance is of high importance to improve the efficiency of sunflower (Helianthus annuus L.) hybrid breeding programmes. We used experimental data from inter‐ and intragroup sunflower hybrids and their parental lines adapted to Central Europe to (i) study the genetic diversity and combining ability and (ii) examine the accuracy to predict hybrid performance based on phenotypic and genomic data. We evaluated 133 intragroup and 104 intergroup hybrids with their parental lines in replicated trials at four environments for grain yield, oil yield and oil content. Furthermore, the parental lines were fingerprinted with 572 AFLP markers. Variance due to specific combining ability was comparable for intergroup and intragroup crosses. This suggested a lack of clearly defined heterotic groups for the sample of studied sunflower lines. Prediction accuracy of hybrid performance based on general combining ability effects was high and could not be increased using genomic selection approaches. For situations where no information on GCA effects of parental lines was available, hybrid prediction based on genomic selection methods was accurate for groups of related lines. For groups of unrelated lines, however, we observed a strong decrease in the prediction accuracy. This suggests that prediction of hybrid performance for crosses based on genetically distant parents remains challenging.