马卡小麦主要农艺性状分析

对29份马卡小麦主要农艺性状进行了考察与分析。结果表明,马卡小麦具有植株高大、分蘖力强和小穗数多等特点。偏相关分析表明,分蘖数与有效穗数,成穗率与有效穗数,千粒重与小穗数偏相关均达极显著水平。单株产量与穗长偏相关显著,与有效穗数、穗粒重偏相关达极显著水平。蛋白质含量与穗长偏相关显著。主成分分析揭示了粒重、有效穗数、成穗率、株高和穗长对变异的贡献率达90.32%。基于因子得分与主成分贡献率的遗传距离在0.62水平上可将供试材料分为四类。这些结果为进一步利用马卡小麦基因资源提供了一定的理论依据。     

莫迦小麦(Triticum macha L.) T型恢复基因Rf3和K型不育基因rfv1的连锁关系

为进一步明确莫迦小麦(Triticum macha) T型恢复基因Rf3与K型不育基因rfv1的连锁关系, 利用T型细胞质背景(T504A/Tm3314 F₂代和T504A//KTm3314A/90(13)21杂交分离群体)的可育株在K型细胞质下的育性测交分析, 明确了来自莫迦小麦的这2个基因连锁并不紧密, 交换值约为16.54%。可利用T型主效恢复基因Rf3提高含有T型主效恢复基因和K型主效不育基因的基础材料的选择效率。     

A reciprocal F1 monosomic analysis of the genetic control of time of ear emergence,number of leaves and number of spikelets in wheat (Triticum aestivum L.)

Summary A reciprocal F₁ monosomic analysis of chromosomal differences between Spica and Bersée was carried out under controlled environment conditions. Chromosomes associated with differences in days to ear emergence, number of leaves and number of spikelets were identified. The results indicated that chromosome 2B of Spica carries a photoperiod insensitivity allele at the Ppd ₂ locus. Both Spica and Bersée appear to have a vernalization insensitity allele at the Vrn ₂ locus on chromosome 5B. On chromosome 3A, 4B, 4D and 6B factors were found with major effects on earliness per se, diffeences in ear emergence and number of spikelets which were independent of photoperiod and vernalization. The possibility that these factors influence growth rate is discussed.     

The physiological control of F1 grass-dwarfs in Triticum aestivum L.

1. 1.
   The morphology and physiology of “grass-dwarfs” produced in the F₁ generation of crosses between certain varieties of Triticum aestivum L. are described. Several treatments were successful in inducing these tufted grasslike plants to flower and set seed. This enabled the crosses producing grass-dwarfs in the F₁ generation to be continued to the F₂ generation where at least half the plants possess the normal wheat phenotype.     
   
   

A reciprocal backcross monosomic analysis of the scab resistant spring wheat (Triticum aestivum L.) cultivar, 'Frontana'

Fusarium head blight (FHB) reduces grain yield of spring wheat and results in deoxynivalenol (DON) production. The resistant spring wheat 'Frontana' could be used to diversify and pyramid resistance. A backcross reciprocal monosomic analysis was conducted to identify 'Frontana' chromosomes with resistance. Disomic lines, one set containing critical chromosomes from 'Frontana' and the other containing chromosomes from susceptible 'Chris', were spray-inoculated and evaluated in separate greenhouse studies (GH-1 and GH-2). Measurements were disease severity at 7 and 14 days, visually diseased kernels, kernels/g and DON content. In GH-2, reciprocal chromosome lines 5B for visually diseased kernels, lines 7B for kernels/g, and lines 4B and 6A for DON content were significantly different. Lines with 'Frontana' chromosomes 3A, 6A and 4D reduced visually diseased kernels, kernels/g and DON content in both studies, while 'Frontana' chromosomes 2A, 2B, 4B and 7B increased susceptibility, as indicated by an increase in these same measurements in both studies. Genes carried on 'Frontana' chromosomes 3A, 6A and 4D could be useful for diversifying and pyramiding sources of FHB resistance.     

Analysis of the yield potential and yield components of F1 and F2 hybrids of crosses between wheat (Triticum aestivum L.) and spelt (Triticum spelta L.)

Summary Crosses of wild barley (Hordeum vulgare ssp. spontaneum and Hordeum vulgare ssp. agriocrithon) with Hordeum vulgare ssp. vulgare were used to select high yielding grain types under dryland Mediterranean conditions. No special difficulties were faced in making the crosses, in eliminating the brittle rachis genes from the grain types or in selecting 6-rowed types in crosses between 2-rowed wild barley and 6-rowed ssp. vulgare varieties. Brittle rachis genotypes, present in the segregating populations were used in developing self-reseeding permanent pastures for dry areas. The best selections were tested in seven trials during 1989–92 and some of them outyielded their parents and also the best improved check variety by 13–22%. Indications for transgressive segregation were obtained for grain yield, straw yield, total biological yield, harvest index and volume weight. The crude protein content of some of the selections was significantly higher than that of the checks. For breeding programs aiming at large seeds, special ssp. spontaneum lines should be used as parents. High grain yield was positively correlated with high straw yield, total biological yield, earliness in heading date, high harvest index and negatively with volume weight. It was concluded that unexploited useful genes, even when not directly observed in wild barley, could be transfered easily into high yielding genotypes by breeding.     

Analysis of disease resistance and quality characters of F1 hybrids of crosses between wheat (Triticum aestivum) and spelt (Triticum spelta)

Summary With the objective of creating new combinations of disease resistance and quality, hybrids between wheat and spelt (spelt is well adapted to cool and wet conditions) were produced and the expression of heterosis was analysed. Three winter wheat varieties were crossed reciprocally with two spelt cultivars and the F₁ hybrids were tested under artificial inoculation with stripe rust, powdery mildew and leaf rust. Disease susceptibility and quality characters (protein content, Zeleny value, grain hardness) were assessed in two year field trials. For stripe rust the F₁ hybrids were resistant if one of the wheat parents was resistant. Combinations with the susceptible wheat cultivar Arina were all susceptible irrespective of using a resistant spelt partner. Although the infection with powdery mildew was rather low, a similar reaction was obtained with the susceptible wheat variety Bernina. Leaf rust revealed very specific varietal influences. The two susceptible wheat varieties Bernina and Arina resulted in susceptible F₁ hybrids when combined with a moderately resistant spelt. Only when they were crossed with a resistant spelt cultivar the F₁ hybrids were resistant. Forno, a leaf rust resistant wheat, gave resistant F₁ hybrids in all combinations. Without exception the quality characters tested showed a negative heterosis effect resulting in protein levels and Zeleny values close to or below the values of the lower parent. It appears to be possible to produce resistant F₁ hybrids, mostly dominated by the resistance level of the wheat partner. The quality of the hybrids is mainly suitable for biscuit and spelt specific products; it needs specific screening for combinations with acceptable breadmaking quality.Abbreviations LSD Least Significant Difference - RH Relative Heterosis     

The effect of chromosome 1AL/1RS translocation on agronomic performance of 85 F2-derived F6 lines from three Triticum aestivum L. crosses

Summary The effect of the 1AL/1RS chromosome translocation on grain yield and other agronomic characteristics of 85 random F₂-derived F₆ bulks from three 1AL 1RS × 1A bread wheat crosses was determined under optimum and reduced irrigation conditions at CIANO, Yaqui Valley, Sonora, Mexico, during the 1991–1992 and 1992–1993 crop production cycles. Harvest plots of 5.0 m² were arranged in an alpha lattice design with three replications. The 1AL/1RS translocation increased grain yield, above-ground biomass, spikes/m², and test weight under both irrigated and dryland conditions. Homozygous chromosome 1A lines, on the other hand, possessed longer spikes with more grains. The 1AL/1RS cultivars had an advantage in 1000-grain weight, which was detected only under optimum irrigation. The translocation lines showed later maturity and longer grainfilling period than the 1A genotypes under one irrigation treatment. A significant relationship between grain yield and test weight was detected only among the 1AL/1RS genotypes, indicating that they possess heavier and plumper grains than the 1A genotypes. These results encourage the continued use of the 1AL/1RS translocation in wheat improvement.     

Genetic diversity within spelta and macha wheats based on RAPD analysis

Genetic diversity in a crop species is basic to improvement of the species and can be estimated at the molecular level. The objective of this study was to estimate genetic diversity within and between spelta and macha wheats. Random amplified polymorphic DNA (RAPD) analysis was conducted on 69 spelta and 32 macha wheat accessions. The classification of spelta and macha accessions, based on Jaccard genetic similarity coefficients for RAPD markers, was consistent with their geographic origin. The results indicated that the germplasm of macha wheat was more diverse than that of spelta wheat. In the dendrogram of macha wheat, four spelta-like accessions grouped together, separate from the remaining macha accessions, suggesting that these accessions were misclassified. In addition, accessions with identical RAPD patterns were found, indicating that these accessions were probably duplicated. Thus RAPD analysis can be used to estimate genetic diversity and identify duplicate accessions in wheat germplasm collections. This revised version was published online in August 2006 with corrections to the Cover Date.     

Inheritance of evapotranspiration and transpiration efficiencies in diallel F1 hybrids of durum wheat (Triticum turgidum L. var. durum)

Inheritance of water use and transpiration efficiency was studied in diallel F₁ hybrids from six cultivars of T. durum, selected for their different responses to drought stress. Plants were grown in 10 l pots at optimal (control) and low soil moisture levels in the glasshouse. GCA and SCA effects were significant at both soil moisture levels. Results demonstrated that evapotranspiration (ETE) and transpiration efficiency (TE) were under additive and dominant gene control. Interactions of GCA and SCA with moisture levels were also highly significant. GCA effects were the major components of the genetic variance of the biological and generative measures of ETE and TE. Narrow sense heritabilities for both ETE and TE based on grain yield were higher at the soil stress moisture level. Heritability estimates of ETE and TE based on the total biological yield, however, declined under the lower soil moisture level. Measures of ETE and TE showed significantly high and positive genotypic and phenotypic correlations among them as well as with grain yield and harvest index. In most cases, genotypic correlations were higher than phenotypic correlations. The results suggest that selection for high ETE and TE in terms of grain yield should be undertaken under both stress and optimal conditions. Selection in early segregating generations may lead to effective identification of desirable recombinants. This revised version was published online in August 2006 with corrections to the Cover Date.     

纤毛鹅观草×普通小麦J-11杂种F1代球形胚愈伤组织的诱导、生长及植株再生

本试验中,R·ciliaris×T. aestivum cv.J-11 的属间杂种幼胚退化于圆球形期,较翁益群等,刘大钧等,颜(?)等以及 Sharma 等报道的显著提前。因此,本文将对产生这种差异的原因及获得杂种的不同途径进行初步的分析与讨论。 1 材料和方法 杂交母本 (♀) 纤毛鹅观草 (R.ciliaris) 和父本 (♂) 普通小麦 (T.aestivum) 品种J—1l 均种植于四川农业大学小麦研究所。常规去雄,人工授粉后7—10天剪取穗子,剥     

Production and characterization of Raphanus sativus-Brassica rapa monosomic chromosome addition lines

Breeding of Raphanus sativus‐Brassica rapa monosomic chromosome addition lines (MALs, 2n = 19) was carried out by backcrossing the synthesized amphidiploid line, Raphanobrassica (R. sativus×B. rapa, 2n = 38, RRAA, line RA89) with R. sativus cv. ‘Shogoin’ (2n = 18, RR). In the first cross of Raphanobrassica× radish, four sesquidiploidal BC₁ plants (2n = 28, RRA, RA89‐36‐1, RA89‐31‐1, RA89‐31‐2, RA89‐31‐3) were successfully developed. In these plants, the chromosome configurations of 9II + 10I and 10II + 8I were observed frequently at first metaphase (MI) of meiosis in pollen mother cells (PMCs). The RA 89‐36‐1 plant produced many seeds in the reciprocal backcrosses with radish. About 50% of the BC₂ plants obtained from the cross of RA89‐36‐1 plant × radish were 2n = 19 plants, followed by 2n = 18 plants (24%) and 2n = 20 plants (19%). In the reciprocal cross, 2n = 19 plants were also developed at the rate of 40%. From analysis of specific morphological traits, 2n = 19 plants were classified into eight types (a‐h). When 25 selected primers were used in polyacrylamide gel electrophoresis, random amplified polymorphic DNA (RAPD) markers derived from B. rapa for each type of MAL were detected in numbers between three for e‐type and 16 for b‐type. RAPD markers specific for each type alone were from one (OPE 05‐344) for h‐type to nine for b‐type. In the g‐type, no marker specific to this type alone was observed. However, 19 bands were common between at least two types. These MAL plants exhibited predominantly the chromosome configuration of 9II + 1I at MI of PMCs, pollen and seed fertility being the same level as the radish cv. ‘Shogoin’. From the morphological traits and DNA markers, eight different MAL types among 10 expected were identified.     

Additive gene action for resistance to Puccinia striiformis F.SP. Tritici in Triticum dicoccoides

Summary Seven single-plant selections of wild emmer, with temperature-sensitive minor-effect genes for stripe rust resistance, were intercrossed in eight combinations. The resulting progenies were studied for a possible additive gene action.The transgressive segregation towards resistance in F₂ observed in all the combinations indicates that additive gene action for resistance indeed occurs in wild emmer. The common occurrence of this phenomenon in random combinations suggests further that several minor-effect genes are involved.Following selection of the most resistant plants in F₂, a marked shift towards resistance was noted in F₃, which demonstrates a positive response to selection. In some instances, additive resistance selected for (in F₂) at the high temperature-profile was expressed (in F₃) also at the low temperature-profile. This kind of resistance, when utilized in breeding programmes, promises therefore to be effective over a range of temperatures.     

Reciprocal monosomic analysis of frost resistance on chromosome 5A in wheat

Summary F₂ monosomic analysis and the direct comparisons between aneuploid series from different varieties of wheat suggest the likelihood of allelic variation. It is impossible however, from these studies to prove unequivocally that allelic variation exists. Some effects can be due to chromosome dosage rather than allelic variation. This disadvantage was overcome by using reciprocal monosomic analysis to study the genetic control of frost resistance on chromosome 5A in wheat. Data support the previous results obtained by F₂ monosomic and substitution analysis. The chromosome 5A has been shown to be the one which carries the major allelic differences that distinguish wheat varieties Chinese Spring, Rannyaya 12 and Mironovskaya 808 for frost resistance.     

Alien chromosome transmission and somatic elimination in monosomic addition lines of Gossypium australe F. Muell in G. hirsutum L.

The efficiency of using monosomic alien addition lines (MAALs) to introgress agronomical traits of interest carried by wild diploid Gossypium species into the main cultivated cotton species G. hirsutum depends on the opportunities of confronting the alien chromosome with the recipient background genome at each generation and on the occurrence of translocations and homoeologous recombinations. The selfed-progeny of five MAALs of G. australe in G. hirsutum was screened with SSR markers to determine the transmission frequency of the alien chromosome and monitor its integrity. Three MAALs revealed a transmission frequency significantly lower than the expected ratio and one MAAL presented an exclusive transmission of the additional chromosome. In these four MAAL the alien chromosome was transmitted almost unaltered. With the fifth MAAL the alien chromosome was normally transmitted but was altered in half of the plants carrying it. In one MAAL, normally carrying brown fiber, the emergence of some plants carrying white and brown fiber revealed the somatic elimination of the additional chromosome. The loss of this chromosome seems to be triggered by its deletion.     

Mapping of the Vrn-B1 gene in Triticum aestivum using microsatellite markers

An F₂ population segregating for the dominant gene Vrn‐B1 was developed from the cross of the substitution line ‘Diamant/'Miro‐novskaya 808 5A’ and the winter wheat cultivar ‘Bezostaya 1′. Microsatellite markers (Xgwm and Xbarc) with known map locations on chromosome 5B of common wheat were used for mapping the gene Vrn‐B1. Polymorphism between parental varieties was observed for 28 out of 34 microsatellite markers (82%). Applying the quantitative trait loci mapping approach, the target gene was mapped on the long arm of chromosome 5B, closely linked to Xgwm408. The map position of Vrn‐B1 suggests that the gene is homoeologous to other vernalization response genes located on the homoeologous group 5 chromosomes of wheat, rye and barley.     

Genomic Relationships of Triticum sharonense with Other S-Genome Diploid Triticum Species

Triticum sharonense was hybridized with autotetra-ploid T. speltoides, T. longissimum and T. bicorne. Meiotic analysis of these hybrids showed that T. sharonense is almost equally related to both T. speltoidcs and T. longissimum, while it is comparatively distant from T. bicorne. Therefore, this study does not support treating T. sharonense as a subspeies or variety of T. lottgissimum.     

Chromosome pairing in haploid plants of radish derived from alien monosomic addition lines

Six haploid plants of radish were obtained via alien monosomic addition lines (2n = 19). One plant was derived from anther culture of an Raphanus sativus‐Brassica oleracea addition line, one plant from the selected smaller seed of an R. sativus‐Sinapis arvensis addition line and four plants from an R. sativus‐B. rapa addition line. During metaphase I of pollen mother cells, two plants exhibited the chromosome pairing of (0‐3)II+ (3‐9)I, three showed (0‐1)III + (0‐3)II + (3‐9)I and the remaining plant (0‐2)II + (5‐9)I. Trivalents seemed to be formed by the pairing between two larger chromosomes and the smaller one with somewhat loose pairing. All haploid plants were inferior to the radish cv. ‘Shogoin’ (2n = 18) with respect to vegetative growth. Their flowers were smaller, with sterile pollen grains, but a few normal flowers with fertile pollen sporadically developed and then produced a few seeds. It is suggested that the radish genome (R, n = 9) might comprise three pairs of homoeologous chromosomes, with the remaining three chromosomes carrying the homologous region(s) that results in a trivalent formation.     

棉花杂交种F1、F2纤维品质性状比较研究

2001-2003年,通过田间试验、定位取样、分株收花、分别检测了杂交棉农杂62F1、F2的主要纤维品质指标。结果分析表明,F1、F2的纤维品质性状均为分离世代,F1、F2纤维长度、比强度、整齐度、麦克隆值、伸长率等品质指标群体平均数趋于一致,群体内个体纤维指标变异均呈正态分布,但峰值和偏斜度差异明显,F1群体中品质较优的个体显著多于F2。F2纤维的整体品质比F1差。