五个小麦优异突变体八个农艺性状的杂种优势和配合力分析

本试验选用５个性状各有特色的小麦优异突变体进行双列杂交（无反交）。利用１０个组合Ｆ１和５个亲本材料研究了８个农艺性状的杂种优势和配合力。Ｆ１显性程度表明：除抽穗期以负向优势为主外，其余７个性状均以正向优势占主导。亲本本身表现与一般配合力效应大小呈显相关，但一般配合力效应大小与杂种优势的表现并不完全一致。作为种质资源，矮秆突变体８９０３７６对降低后代株高最有利，大粒突变体核生二号最有利于提高后代的     

抗黄矮病小麦品系粒重遗传特性研究

采用Griffing方法I,对抗黄矮病 (BYDV)小麦品系单株粒重、单穗粒重和千粒重遗传特性研究结果表明 ,3种粒重遗传符合加性 显性遗传模型 ,细胞质作用对千粒重影响较小 ,株粒重和穗粒重则存在明显核质互作 ;3个抗黄矮病品系中“临抗 1号”单株产量特殊配合力方差最大 ,一般配合力效应值也较高 ,亲本组合间存在极显著差异 ,为优良抗病丰产亲本 ,在抗病育种中有较大利用价值。     

两系杂交水稻主要性状配合力与亲本灿粳分化关系的研究

选用４个光温敏核不育系及５４个常规品种（系）,按ＮＣⅡ设计配制杂交组合,以灿粳特异ＲＦＬＰ标记及形态指数法检测供试品种（系）的灿粳分化程度,研究两系杂交水稻主要性状一般配合力及特殊配合力与双亲灿粳分化的关系。结果表明,（１）多数品种的灿粳遗传分化和形态分化相一致,只有个别品种不一致;（２）组合间一般配合力方差大于特殊配合力方差,基因加性效应更重要;（３）亲本的一般配合力效应及其特殊配合力效应对Ｆ１     

苦瓜产量杂种优势与配合力研究

选用8个高世代绿苦瓜自交系,按Griffing完全双列杂交第2种方法设计试验,对苦瓜产量的杂种优势和配合力效应进行研究。结果表明:28个杂交组合有26个呈现正向离中优势,有23个呈现正向超亲优势,22个组合比对照增产;在8个试验亲本中,4个亲本的一般配合力效应为正向效应,另外4个为负向效应,亲本B的一般配合效应值极显著高于其它亲本;21个组合双亲间特殊配合力效应表现为正向效应,效应值最高的组合为E×H(2.15),其次是B×H(1.51)、D×H(1.28)、A×G(1.23)和C×G(1.05)。并对苦瓜丰产性育种的亲本选择选配进行了讨论。     

两系杂交水稻主要性状配合力与亲本籼粳分化关系的研究

选用4个光温敏核不育系及54个常规品种（系）,按NCII设计配制杂交组合,以籼粳特异RFLP标记及形态指数法检测供试品种（系）的籼粳分化程度,研究两系杂交水稻主要性状一般配合力及特殊配合力与双亲籼粳分化的关系。结果表明,①多数品种的籼粳遗传分化和形态分化相一致,只有个别品种不一致;②组合间一般配合力方差大于特殊配合力方差,基因加性效应更重要;③亲本的一般配合力效应及其特殊配合力效应对F     

糯玉米淀粉RVA黏度性状配合力与杂种优势分析

蒸煮食味品质是评价鲜食糯玉米品种优劣的核心指标。为探究糯玉米蒸煮品质性状的配合力、杂种优势及与亲本遗传距离关系，本研究选用55个糯玉米自交系，采用NCⅡ设计组配的156个杂交组合，研究其快速黏度分析（RVA）特征谱配合力效应并结合单核苷酸多态性（SNP）标记，分析遗传距离与杂种优势、配合力的相关性。结果表明，在被测自交系中，ZFF、XH55和NFHH一般配合力效应较高，利用其组配的杂交组合峰值黏度也普遍较高，说明利用这3个自交系组配杂交组合后代产生优势杂交种的潜力较大。相关性分析结果发现，SNP分子标记遗传距离与RVA黏度性状杂种优势显著相关，但相关系数普遍偏低（0.162～0.345），说明遗传距离对糯玉米杂交组合RVA黏度性状的预测具有一定的价值，但遗传距离与F1黏度性状之间的相关程度不足以准确预测杂种优势。另外，亲本的总配合力和特殊配合力与杂种优势显著相关，决定系数也较高，变幅在-0.781～0.830和-0.662～0.786。结果表明，在预测糯玉米黏度性状的杂种优势时，不能只依靠遗传距离，还应重点考虑亲本的配合力。本研究为后续优质糯玉米品种选育提供了亲本以及杂交组配的理论依据...     

宽柄芥(酸菜)不育系与父本系主要农艺性状配合力及遗传参数分析

选用3个自育宽柄芥不育系和4个父本系(自交系),采用NCⅡ(不完全双列杂交)设计的原理和方法,分析了宽柄芥杂交亲本及组合主要农艺性状的一般配合力、特殊配合力及遗传参数。结果表明:F1代柄肋鲜重、开展度、单株鲜重、产量、株高的特殊配合力高于一般配合力,说明大多数农艺性状受非加性效应影响;各农艺性状广义遗传力大于狭义遗传力,表明这些性状主要由非加性基因控制,受环境影响大;不育系K46A和DJA除个别性状外10个性状GCA均呈正向效应,是有利用价值的亲本。不育系K6A及父本系K42、DJK、SGK、HK部分性状的GCA呈正向效应,部分呈负向效应,可根据育种目标有针对性地选用;"K6A×K42""DJA×HK""K46A×SGK"组合具有很强的杂种优势和增产潜力,在实际生产中应加强利用。     

有机肥配施荧光假单胞菌肥对玉米产量与复垦土壤磷素有效性的影响

复垦土壤贫瘠,磷素含量极低,严重影响作物的生长发育。研究化肥、有机肥配施荧光假单胞菌对玉米产量和复垦土壤磷素形态以及酶活性的影响,为加速培肥矿区复垦土壤提供技术支持和理论依据。该研究在山西省晋中市采煤塌陷区进行了2a的定位培肥试验,共设置7个处理：不施肥（CK）、单施化肥（CF）、化肥配施荧光假单胞菌（CFB）、单施有机肥（M）、有机肥配施荧光假单胞菌（MB）、化肥配施有机肥（MCF）、化肥有机肥配施荧光假单胞菌（MCFB）。采集各处理土壤样品测定相关指标,并通过相关性分析和结构方程模型来探究各形态磷与有效磷以及土壤磷酸酶之间的关系。结果表明：1）在整个试验周期（2021—2022年）,与CK相比,不同施肥处理均能显著提高玉米产量以及各形态磷素。其中,以MB处理下的玉米产量、有效磷、磷活化系数、不稳定态磷以及部分不稳定态磷含量最高,与CK处理相比,玉米产量显著提高2.4倍,有效磷含量、磷活化系数值、不稳定态磷含量、部分不稳定态磷含量分别显著提高4.5倍、4.67倍、0.98倍、1.16倍。2）与CK处理相比,化肥、有机肥配施荧光假单胞菌能够显著提高土壤微生物量磷以及酸性和碱性磷酸酶活性,配施荧光假单胞菌后,微生物量磷水平和碱性磷酸酶活性均以MB较M处理提升效果最佳,分别显著提高27.08%和9.56%。3）结合相关性分析以及结构方程模型,随着荧光假单胞菌和化肥有机肥的施入,在提高不稳定态磷素含量的同时也提高有效磷的供应能力,促进磷素在农田生态系统中的循环转化,产生积极的正向影响。化肥、有机肥配施荧光假单胞菌能够一定程度上影响复垦土壤玉米产量及产量性状、各形态磷素及有效性和微生物活性,对复垦土壤脆弱的农田生态系统产生积极影响。     

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。     

白桦幼苗株高和地径的遗传效应分析

采用P(P -1)/2 完全双列杂交设计对6 个白桦优良个体生长性状进行一般配合力( GCA) 和特殊配合力(SCA) 分析,结果表明：2个性状同时受加性和非加性效应控制。同一亲本不同性状的一般配合力差异较大,同一性状在不同亲本间的一般配合力差异也比较大,在6个亲本中Q2 是最好的亲本,M2次之。同一性状不同组合和同一组合各性状的SCA 效应值均有较大差异,试验中苗高地径的特殊配合力最高的是8×Q1,苗高地径两个性状的一般配合力均高于特殊配合力,苗高地径的遗传力属于高强度遗传力,可以进行早期选择。     

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.     

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.     

Adaptive values of wild × cultivated sorghum (<Emphasis Type="Italic">Sorghum bicolor</Emphasis> (L.) Moench) hybrids in generations F<Subscript>1</Subscript>, F<Subscript>2</Subscript>, and F<Subscript>3</Subscript>

Gene flow between cultivated and their wild relatives is one of the main ecological concerns associated with the introduction genetically modified (GM) cultivars. GM sorghum cultivar has been developed and its commercial production may be possible in the near future. The rate of gene flow depends on the fitness of wild × cultivated sorghum hybrids. The study aimed at estimating adaptive values of wild × cultivated sorghum hybrids in generations F₁, F₂, and F₃ compared to their parents. Artificial crosses of four wild sorghums, five cultivated sorghums, and two male sterile lines were made to produce the F₁ generation, which were advanced to F₂ and F₃. Each hybrid generation and their respective parents were evaluated for their adaptive value at two sites in a randomised complete block design with seven replicates. The resulting progenies did not show serious fitness penalties. Some hybrids were as fit as their respective wild parents and no consistent differences exist between the three generations studied. Thus, the resultant wild × cultivated hybrids may act as avenue for introgression.     

Heterosis in numbers of differentiated,degenerated, and surviving spikelets and their relations to the dry matter production in F1 hybrids of rice

Heterosis in the number of differentiated, degenerated, and surviving spikelets in two important Chinese F₁ hybrids Shanyou 63 (SY63) and Yayou 2 (YY2) and their parents was observed under solution culture conditions. The results indicated that the number of differentiated, degenerated, and surviving spikelets all showed a very high value for mid-parental (MP) heterosis in the hybrids at both panicle and plant levels. The increase in the number of surviving spikelets primarily depended on that of the number of differentiated spikelets. The percentage of degenerated spikelets showed a positive value for MP and higher-parental (HP) heterosis (increase) in SY63, while it showed a negative value for MP and HP heterosis (decrease) in YY2. Morphologically, the components of the number of surviving spikelets increased in the hybrids, especially the number of surviving secondary rachis branches. Dry matter production at heading showed a high value for MP and HP heterosis. However, the ratio of dry matter weight to the number of differentiated spikelets did not show a MP heterosis. The hybrids showed a lower percentage of degenerated spikelets for the same ratio of dry matter weight to the number of differentiated spikelets. The N uptake in the hybrids showed a MP and HP heterosis, but the efficiency of the N in producing the number of surviving spikelets showed a negative value for MP and HP heterosis. The MP and HP heterosis in the sink-source ratio of the number of surviving spikelets to the leaf area varied considerably with the combinations. These findings suggested that still many characters could be further improved in F₁ hybrid rice.     

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。     

GENETIC ANALYSIS OF CHLORIDE CONCENTRATION IN ORIENTAL TOBACCO GENOTYPES

A high chloride concentration in oriental tobacco leaf has a detrimental effect on tobacco quality and its burning properties. In order to determine the inheritance of chloride concentration in oriental tobacco leaf, eight tobacco genotypes showing genetic variability for chloride concentration on the basis of our previous investigation were crossed in a diallel program. Parental genotypes and their F1 hybrids were evaluated in greenhouse experiment using randomized complete block design with three replications. Each replication consisted of two pots (one plant per pot). Cultivation took place in plastic plant pots which contained 10 kg soil from the fields of the northwest Iran where the oriental tobacco type is planted. Standard agrotechnical practices for this tobacco type were applied during growth. Tobacco was harvested when it reached technical maturity then it was sun-cured. Percentage of chloride in cured leaves was determined as defined by CORESTA (Cooperation Center for Scientific Research Relative to Tobacco, Paris, France). Analysis of variance was performed to determine the effect of genotypes on chloride concentration and showed significant variability among genotypes for this trait. Diallel analysis showed that general combining ability (GCA) and specific combining ability (SCA) effects for chloride concentration were highly significant indicating that both additive and dominant gene effects were important in controlling the chloride concentration. However, the mean square for specific combining ability was greater than those of general combining ability that shows the predominance of the non-additive genetic effects in controlling the chloride concentration. Therefore, the interpopulational breeding strategy using the heterosis effect could give superior gains to this character.     

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。     

Mode of inheritance of zinc accumulation in maize

The present study was undertaken to investigate the genetic nature of zinc (Zn) accumulation in the ear‐leaves of maize (Zea mays L.) plants. Fourteen inbred lines were evaluated. Out of which, five inbreds were chosen, two high Zn accumulators (Rg‐5 and Rd‐2), two low Zn accumulators (Rg‐8 and G‐307) and a moderate one (K‐64). These five parental inbreds were utilized to obtain all possible ten F1 hybrids (in one direction), 10 F2, 10 Bl, and 10 B2. All genotypes were planted and Zn was estimated at 50% tasseling stage. Zinc accumulation in the present genotypes was found to be genetically controlled and affected by additive genes. Significant values were obtained for the General Combining Abilities (GCA) but not for the Specific Combining Abilities (SCA) and the high Zn accumulating parents were the best general combiners. Four genes were found to be the minimum segregating factors in the (high x low) crosses for Zn accumulation.     

Hybridization mechanisms between the endangered marble trout (Salmo marmoratus) and the brown trout (Salmo trutta) as revealed by in-stream experiments

Populations of the marble trout (Salmo marmoratus) are critically declining due to introgression by brown trout (S. trutta) strains. Hybrids between the two forms are fertile and presently predominant in most rivers of the species’ range.The involved hybridization mechanisms have been studied through two large scale in-stream experiments (Driselpoh and Stopnikarca) as 50% of each species have been stocked at the age of one year in fishless streams, each fish being individually marked. Diagnostic molecular markers were applied to test a partial reproductive isolation between the two species. Emphasis was put on survival and growth patterns of stocked fish (parental generation) as well as on fish hatched within the stream (F₁ generation).No evidence of a partial reproductive barrier between the two species was observed. Survival of the parental generation depended on the year in both streams, as well as on the species in Stopnikarca, but was identical for both species in Driselpoh. In both streams survival of instream hatched individuals measured from 0+ to 2+ was lower for brown trout. In Driselpoh, F₁ 0+, 1+ and 2+ hybrids were larger than pure individuals. Larger hybrids were only observed in Stopnikarca when analyses focused on individuals in inter-specific competition suggesting that heterosis and stress effects may explain the observed size differences.Our results point out important ecological differences between marble and brown trout and have shown that hybridization can easily take place. The findings indicate that high F₁ hybrid presence, survival and heterosis effects may impede marble trout rehabilitation in the area.