玉米改良单交种选育方法的研究：Ⅱ.姊妹系和姊妹种的配合力研究

以ＧｒｉｆｉｎｇＩＩ双列杂交试验和ＮＣＩＩ遗传交配试验，测定玉米８个姊妹系及其２８个姊妹种的一般配合惫，结果两者基本一致。玉米妹系的一般配合力是一种遗传特性，它既可遗传给其组成的姊妹种，又能通过姊妹和种遗传给其组成的改良单交种；姊妹种的一般配合力与其双亲姊妹系一般配合力均值之间没有显著差异，并呈密切相关，这阐明了改良单交种与其对应的普通单交种相似的原因，并为改进和简化改良单交种选育程序提供理论依据     

Genetic Effects on Host × Strain Interaction in the Symbiosis of Vicia faba and Rhizobium leguminosarum

50 Vicia faba lines were inoculated with 4 strains of Rhizobium leguminosarum in all possible combinations under greenhouse conditions in 5 replications. A root-sterile method was used for the cultures. Characters such as plant height, leaf colour, number and colour of nodules, the dry weights of shoot, root and nodules, and the nitrogen content were recorded, after 10 weeks. It was demonstrated by analysis of variance that, for example, for the dry matter of the shoot only 1.9 % of the total phenotypic variance was caused by interaction between Vicia and Rhizobium genotypes, but 24.7 % Was conditioned by the faba bean genotypes and 73.4 % by the Rhizobium strains. Differences of Vicia faba genotypes in their reaction to different Rhizobium strains were detected by joint regression analysis.     

Resistance to common bacterial blight in Phaseolus vulgaris L. recombinant inbred lines under natural infection of Xanthomonas axonopodis pv. phaseoli

Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore, the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease resistance under natural infection of the pathogen in 109 recombinant inbred lines (F₇) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments, as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance breeding program. The data of the genetic parameters were compared to those calculated for the F₃ generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F₃ were 26.85% and 0.26, respectively, whereas in F₇ they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population, that in the future, along with other pathogen variability studies and tests in other environments, may provide more information regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB resistant varieties. This revised version was published online in July 2006 with corrections to the Cover Date.     

Two genes and linked RAPD markers involved in resistance to Fusarium oxysporum f. sp. Ciceris race 0 in chickpea

The inheritance of resistance to fusarium wilt race 0 of chickpea and linked random amplified polymorphic DNA (RAPD) markers were studied in two F₆:₇ recombinant inbred line (RIL) populations. These RILs were developed from the crosses CA2156 × JG62 (susceptible × resistant) and CA2139 × JG62 (resistant × resistant), and were sown in a field infected with fusarium wilt race 0 in Beja (Tunisia) over 2 years. A1:1 resistant to susceptible ratio was found in the RIL population from the CA2156 × JG62 cross, indicating that a single gene with two alleles controlled resistance. In the second RIL population (CA2139 × JG62) a 3:1 resistant to susceptible ratio indicated that two genes were present and that either gene was sufficient to confer resistance. Linkage analysis showed a RAPD marker, OPJ20600, linked to resistance in both RIL populations, which is present in the resistant parent JG62.     

Introduction of a self-compatible gene of Lolium temulentum L. to perennial ryegrass (Lolium perenne L.) for the purpose of the production of inbred lines of perennial ryegrass

Interspecific hybrids between self-compatible species, Lolium temulentum L. and self-incompatible species, L. perenne L. were obtained using embryo rescue. Two cycles of backcrossing of interspecific hybrids with L. perenne were carried out. A 1: 1 segregation ratio of self comatibility and incompatibility was observed in backcross generations. These segregation data confirmed that self-compatibility of L. temulentum was controlled by a single gene. It suggested that the self-compatible gene of L. temulentum could be introduced to self-incompatible plants of L. perenne through interspecific hybridization. It appears that utilization of a self-compatible gene of L. temulentum would be useful for production of inbred lines of L. perenne. The possibility of breeding procedures of perennial ryegrass using a self-compatible gene was discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

早熟硬粒型玉米自交系H21选育研究

１９７８年以来，作者坚持了以超黄早４为主要目标的早熟粒型玉米自交系选育研究，取得的主要成果为Ｈ２１。用Ｈ２１取代烟单１４号，鲁玉２号，掖单４号等组合的黄早４亲本，均比原组合表现优越，取代西玉３号中的“５０２”亲本，Ｆ１产量也有所提高，Ｈ２１选育成功的关键，一是选用中国和美国玉米品种资源来组配优缺点互补的基本材料；二是紧扣育种目标，加大选择压力，采用骨干系测交，迅速育成了超标的新杂交种。     

A new locus for resistance to brown planthopper identified in the indica rice variety DV85

The brown planthopper (BPH) is one of the most destructive insect pests of rice. Resistant varieties have proved to be one of the most economic and effective measures for BPH management. In this study, an indica rice ‘DV85’ showed resistance to biotype 2 of BPH by bulked seedling test, and a recombinant inbred line (RIL) population derived from a cross between a susceptible rice ‘Kinmaze’ and ‘DV85’ was phenotyped to map genetic factors conferring BPH resistance in ‘DV85′. Composite interval mapping revealed that one quantitative trait locus (QTL) with a LOD score of 10.1 was detected between XNpb202 and C1172 on chromosome 11. This QTL was designated as Qbph11. Qbph11 explained 68.4% of the phenotypic variance of BPH resistance in this population. The allele from the resistant parent ‘DV85’ at Qbph11 reduced the damage caused by BPH feeding and would be very useful in breeding resistant rice varieties via marker‐assisted selection.     

Inheritance of Aluminum Tolerance and its Effects on Grain Yield and Grain Quality in Oats (Avena Sativa L.)

Summary Aluminum toxicity due to the cation Al⁺³ is a major factor limiting yields in acid soils. Wide genetic variability to aluminum tolerance is found in oat genotypes. The objectives of this study were to determine the number of genes controlling aluminum tolerance in oats and to verify if any detrimental effects were present of the aluminum tolerance genes on grain yield and grain quality in Al⁺³free soils. Aluminum tolerance was estimated as the average regrowth of the main root after exposure to toxic levels of Al⁺³ in a hydroponic solution under controlled conditions. The number of genes controlling that trait was estimated from the distribution of the average root regrowth frequencies in a population of 333 recombinant inbred lines (RIL's) in generations F_5:6 and F_5:7. The effects on grain yield and grain quality were assessed in a subpopulation of 162 RIL's chosen based on their aluminum tolerance response. Aluminum tolerance in the evaluated population was controlled by one dominant major gene with the tolerant genotypes carying Al _a Al _a and the sensitive ones al _a al _a alleles. No detrimental effects of the Al _a allele on grain yield or grain quality were detected.Part of the Master of Science dissertation of the first author     

关于水稻穗芽的生理学研究

利用重组自交系籼稻中-156/谷梅2号304份株系为材料，在田间条件下营造高温、高湿的小气候，以“穗穗芽率”及“粒穗芽率”为指标，筛选易发生穗芽与不易发生穗芽的极端材料，比较研究重组自交系亲本与各供试株系籽粒在穗芽发生期间的生理差异。结果表明，该重组自交系母本谷梅2号比父本中-156易穗芽，在正常成熟过程中籽粒内源GA₁含量水平高于中-156，ABA含量水平低于中-156；谷梅2号籽粒淀粉酶活性也高于中-156。花后15 d至完熟的籽粒灌浆期如遇高温、高湿条件，谷梅2号及易穗芽的株系籽粒内源GA1随雨日渐增，增幅高于中-156及不易穗芽的株系，同时其淀粉酶活性回升，在正常成熟过程中花后15 d后籽粒中淀粉酶活性与日渐降，但其幅度远高于父本中-156及不易穗芽的株系，这种变化可能是易穗芽的亲本与株系对高温、高湿敏感诱发穗上发芽的主要生理基础。     

Heterosis in Primary Hexaploid Triticale with Heterozygous Wheat or Rye Genome*)

Twelve primary hexaploid triticale (X Triticosecale Wittmack), synthesized from, three lines of tetraploid wheat (Triticum durum L., T. turgidum L.) and four inbred lines of rye (Secale cereale L.), were used to produce 18 crosses with homozygous wheat and heterozygous rye genome and 12 crosses with heterozygous wheat and homozygous rye genome. Parents and crosses of triticale, wheat, and rye were tested for two years (rye for one year only) in two-replicate block designs with 1 m²-plots. Data were assessed for plant height, grain yield and for yield-related traits. Performance of triticale crosses was considerably lower than that of the wheat and rye crosses. The amount of heterosis varied greatly between years. Positive and mainly significant heterosis was revealed in triticale generations F₁ and F₂. The average values were closer to those in wheat than to those in rye. For most characters a high level of heterosis was retained in tnucalt1 generation F₂. Heterozygosity of the wheat and rye genome both contributed to heterosis in triticale. However, gene action of the rye genome strongly depended on the homozygous wheat background: one wheat line almost completely suppressed and another greatly stimulated the heterotic effect of the rye genome. In the later case, the amount of heterosis was related to that in rye per se. Information from hybrid rye breeding may therefore be used when establishing gene pools for hybrid breeding in triticale.