Transcriptomic and metabolomic analysis provides insights into lignin biosynthesis and accumulation and differences in lodging resistance in hybrid wheat

The use of hybrid wheat is one way to improve the yield in the future.However,greater plant heights increase lodging risk to some extent.In this study,two hybrid combinations with differences in lodging resistance were used to analyze the stem-related traits during the filling stage,and to investigate the mechanism of the difference in lodging resistance by analyzing lignin synthesis of the basal second internode(BSI).The stem-related traits such as the breaking strength,stem pole substantial degree(SPSD),and rind penetration strength(RPS),as well as the lignin content of the lodging-resistant combination(LRC),were significantly higher than those of the lodgingsensitive combination(LSC).The phenylpropanoid biosynthesis pathway was significantly and simultaneously enriched according to the transcriptomics and metabolomics analysis at the later filling stage.A total of 35 critical regulatory genes involved in the phenylpropanoid pathway were identified.Moreover,42%of the identified genes were significantly and differentially expressed at the later grain-filling stage between the two combinations,among which more than 80%were strongly up-regulated at that stage in the LRC compared with LSC.On the contrary,the LRC displayed lower contents of lignin intermediate metabolites than the LSC.These results suggested that the key to the lodging resistance formation of LRC is largely the higher lignin synthesis at the later grain-filling stage.Finally,breeding strategies for synergistically improving plant height and lodging resistance of hybrid wheat were put forward by comparing the LRC with the conventional wheat applied in large areas.

Studies on the Developmental Genetics of Tiller Number in Three-line Indica Hybrid Rice

Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.

The contribution of distant hybridization with decaploid Agropyron elongatum to wheat improvement in China

Wheat is a staple food crop in the world as well as in China. Because of the progress of wheat breeding and other agricultural ＂sci-technologies, the wheat grain yield per unit area has increased more than five folds from 1952 to 2006 in China. The first part of this article briefly reviews the history of wheat breeding in China. Second, the establishment of ＂Triticum aestivum-Agropyron＂ distant hybridization system and its contribution to wheat production and breeding in China are summarized. Finally, the future challenges of wheat breeding are discussed, which include how to increase the utilization efficiencies of water, soil nutrient and light energy through breeding. As an example, our research progress on how to increase light use efficiency in wheat through breeding is introduced and discussed.

Programmed cell death, antioxidant response and oxidative stress in wheat f lag leaves induced by chemical hybridization agent SQ-1

Male sterility induced by a chemical hybridization agent （CHA） is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in thistudy. CHA induced programmed cell death （PCD） as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling （TUNEL） and DNA laddering analysis. In the early phase, CHA-SQ-1 trig- gered organelle changes arid PCD in wheat leaves accompanied by excess production of reactive oxygen species （O2- and H202） and down-regulation of the activities of superoxide dismutase （SOD）, catalase （CAT） and guaiacol peroxidase （POD）. Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-l-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding.

The Growth Analysis in the Kernel Filling Process of K-Type Hybrid 901 and Its Parent Wheat

Using Matlab software, the grain filling process of hybrid wheat 901 and its parents was fitted by Richards equation W = A/（1 ＋ Be^-kt in order to study the characteristics of grain filling of the hybrid. The active grain growth period of the hybrid was 6 d longer than that of Shaan 229, and its final grain weight （43.7 g/1 000 grains） was higher than that of Shaan229 （36.3 g/1 000 grains）. N values of 901 and R205 were both less than 1, and their grain growth was faster in the early filling stage, while slower in the middle-late stage. N value of Shaan 229 was 〉1~ and its growth was slower in the early stage and faster in the middle stage. The period of early stage of 901 was shorter and of middle-late stage was longer. The situation of Shaan 229 was totally reversed. For parents, the father plant R205 was similar to hybrid wheat 901, whereas its mother plant K3314A similar to Shaan 229. It has been found that Richards equation was more suitable for fitting the grain filling process of wheat than Logistic equation.

Grain Sink Strength Related to Carbon Staying in the Leaves of Hybrid Wheat XN901

XN901 is a K-type three-line hybrid wheat with a high yield potential, and its leaves and stem remaining green during grain maturation, suggesting much assimilate stay in leaves and stem. The grain water content, grain volume, carbohydrate content, and enzyme activity of sucose metabolism in the grain, as well as source-sink relationship were studied in order to investigate the physiological reason of the assimilate remaining in leaves and stem at the late stage. The results showed that the hybrid grains had more water and soluble sugar, higher activities of acid invertase and sucrose synthase at the early stage that led to a faster expansion growth, greater grain volume and faster starch synthesis at the early to mid stage of grain development. Also it had a longer period for actively filling. As a result, the grain weight and yield of the hybrid were increased by 14 and 15% respectively compared to that of Shaan 229. Additionally, the biomass of XN901 was 41.7% more than that of control, but its harvest index was 9% lower than Shaan 229. However, its lower activity of sucrose synthase indicated a lower sink activity at the late stage, resulting in a slow rate of filling and starch synthesis. Also, the hybrid wheat XN901 had a large source-sink ratio. It is the main reason for much assimilate remaining in the straw at the late stage and lower harvest index. Strengthening the sink activity and raising the harvest index should be the key means of improving the yield of hybrid wheat.

Yield-related agronomic traits evaluation for hybrid wheat and relations of ethylene and polyamines biosynthesis to filling at the mid-grain filling stage

Because of the yield increase of 3.5-15%compared to conventional wheat,hybrid wheat is considered to be one of the main ways to greatly improve the wheat yield in the future.In this study,we performed a principal component analysis(PCA)on two-line hybrids wheat and their parents using the grain weight(GW),the length of spike(LS),the kernel number of spike(KSN),and spike number(SPN)as variables.The results showed that the variables could be classifed into three main factors,the weight factor(factor 1),the quantity factor 1(factor 2)and the quantity factor 2(factor 3),which accounted for 37.1,22.6 and 18.5%,respectively of the total variance in different agronomic variables,suggesting that the GW is an important indicator for evaluating hybrid combinations,and the grain weight of restorer line(RGW)could be used as a reference for parents selection.The hybrid combination with a higher score in factor 1 direction and larger mid-parent heterosis(MPH)of the GW and its parents were used to carry out the analysis of grain fling,1-aminocylopropane-1-carboxylicacid(ACC)and polyamine synthesis related genes.The results suggested that the GW of superior grain was significantly higher than that of inferior grains in BS1453xJS1(H)and its parents.Both grain types showed a weight of H between BS 1453(M)and JS1(R),and a larger MPH,which may be caused by their differences in the active fling stage and the grain fling rate.The ADP-glucose pyrophosphorylase(AGPase),granule bound starch synthase I(GBSS/),starch synthaseⅡ(SSS),and starch branching enzyme-Ⅰ(SBE-1)expression levels of H were intermediated between M and R,which might be closely related to MPH formation of the GW.Compared with R and H,the GW of M at maturity was the lowest.The expression levels of spermidine synthase 2(Spd2),ornithine decarboxylase(ODC)and S adenosylmethionine decarboxylase(SAMDC)had significantly positive correlations with the grain flig rate(1=0.77,0.51,0.59"),suggesting their major roles in the grain flling and heterosis formation.These provide a theoretical basis for improving the GW of photo-thermo-sensitive male sterile lines(PTSMSL)by changing the endogenous polyamine synthesis in commercial applications.

Effects of Different Row Ratios of Male and Female Parents and Application Amount of Nitrogen Fertilizer on Hybrid Wheat Seed Production and Its Component Factors

In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents and application amount of nitrogen fertilizer on hybrid wheat seed production and its component factors. The results showed that the seed production increased with the increase in the number of female parent row. When the row ratio of male and female parents was 2 ∶ 6,the seed production was 3 683. 8 kg/ha; when the application amount of nitrogen fertilization was 50 kg/ha,the seed production was 3 649. 4 kg/ha; the interaction between the row ratio of male and female parents and the application amount of nitrogen fertilizer indicated that when the row ratio of male and female parents was 2∶ 6 and the application amount of nitrogen fertilizer was 300 kg/ha,the seed production reached the highest( 4160. 6 kg/ha). The row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the component factors of seed production,including the number of grains per spike,spike weight and setting percentage. When the row ratio of male and female parents was 2∶ 5,the number of grains per spike,spike weight and setting percentage were the highest at 26. 7 grains,1. 12 g,and 62. 6% respectively; when application amount of nitrogen fertilizer was 450 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 26. 0 grains,1. 08 g,and59. 2% respectively; the interaction of row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the number of grains per spike,spike weight and setting percentage; when the row ratio of male and female parents was 2∶ 5 and the application amount of nitrogen fertilizer was 300 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 29. 6grains,1. 24 g,and 71. 6% respectively. The number of grains per spike is the largest component factor for seed production. Increasing the number of grains per spike can increase the seed production. According to the effects of row ratio of male and female parents and application amount of nitrogen fertilizer on the component factors of seed production,the optimal condition was 2∶ 5-2∶ 6 for row ratio of male and female parents and 300-450 kg/ha for application amount of nitrogen fertilizer.

Research and application of hybrid wheat in China

Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.

Comparative Proteomic Analysis of Wheat (Triticum aestivum L.) Hybrid Necrosis

Hybrid necrosis is the gradual premature death of leaves or plants in certain Fj hybrids of wheat （Triticum aestivum L.）. Comparison of protein expression in necrotic and normal wheat leaves showed that the abundance of 33 proteins was changed significantly, and 24 of these proteins were identified. These proteins were involved in plant growth and development, antioxidation, photosynthesis and carbon assimilation, amino acid and protein biosynthesis, cytological signal transduction, DNA and RNA modification, protein transport, folding and assembly according to their functions. The down-regulation of uroporphyrinogen decarboxylase and the up-regulation of lipoxygenases in necrotic leaves may be related to the oxidative stress in the necrotic cells. The heat shock proteins may play the cytoprotective role. The differential expression of photosynthesis and carbon assimilation related proteins indicated chlorophyll biosynthesis and chloroplast development were inhibited and might finally cause the gradual chlorosis and cell death in necrotic leaves. The results of this study give a comprehensive picture of the post-transcriptional response to necrosis in hybrid wheat leaves and serve as a platform for further characterization of gene function and regulation in wheat hybrid necrosis.

Studies on the Utilization Potentiality of the Nucleo-Cytoplasmic Hybrid in Wheat

A series of comparative studies was carried out on the genetic effects of 25 alien cytoplasms of wheat on the growth potential, heading stage, fertility, resistance against diseases, important agronomic traits and its heterosis of 125 nuclei-cytoplasmic hybrids of wheat. The results indicated that there were clearly effects of alien cytoplasms on some characteristics, but the nucleus still exerted main effect on other characteristics. The effect of interactions between nucleus and cytoplasm was comparative obvious in some combination. Consequently, when we utilize the effects of alien cytoplasms, we should pay full attention to the facts such as the characteristic to be improved, the effects of cytoplasm, nucleus, the nucleus-cytoplasm interactions on that characteristics. From the preliminary studies, we believed that the cytoplasmic types of M0, S1, Sv, D2, D and B, and the nucleo-cytoplasmic hybrids of (Ae. sharonensis)-B174, (Ae. squarrosa)-352-35 (Ae. cylindrica)-352-35, (Ae. cylindria)-E EN-1, (Ae. cylindrica)-NPFP, and (Ae. speltoides)-352-35 would have some utilization potentiality in cultivar improvement.

An Alternative Analysis on Nilsson-Ehle’s Hybridization Experiment in Wheat —Theory of Dual Multiple Factors and Three Normal Distributions on Quantitative Inheritance (Continuation)

In this paper, an analysis on Nilsson-Ehle’s hybridization experiment in wheat was done by means of self-fertilization method along with the pericarp inheritance. It showed that because seeds of wheat were coated with 2n tissues of mother’s body, the grain colors were determined by mother’s genotype. The color of the F1 grains in this experiment was old red. The phenotypes of the F2 grains were uniformly medium red and did not segregate. Grains in the F3 generation segregated in the ratio 6 red (varying intensities of red) to 1 white with a definite probability respectively. This is the consequence of additive effect of 3 gene pairs and belongs to discrete distribution rather than continuous distribution. Therefore, the multiple-gene hypothesis based on this experiment cannot solve the continuous variations in inheritance of quantitative characters.

Synthesis of a Wheat/Maize Hybrid CENH3 Gene, the Genetic Transformation of Wheat, Its Chromosomal Localization and Effects on Chromosome Behaviors in Wheat/Maize Somatic Hybrids

Centromere-specific histone H3 (CENH3) replaces the canonical histone H3 in nucleosomes of functional centromeres, and plays important roles in faithful chromosome segregation during cell division. CENH3 is also important in the recognition of alien centromeres and determines the accommodation or elimination of alien chromosomes in interspecific or intergenic hybridization. In this study, a maize full length CENH3 with a yellow fluorescent protein (YFP) tag at C-terminus (ZmCENH3-YFP) and a synthetic hybrid wmCENH3 with the N-terminus from wheat CENH3 and the histone fold domain (HFD) from maize tagged with a red fluorescent protein (RFP) at the C-terminus (wmCENH3-RFP) were transformed to wheat by biolistics transformation. Transgenic wheat plants with both ZmCNEH3-YFP and wmCENH3-RFP genes were identified by PCR. The expression of ZmCENH3-YFP was not observed, while the expression of wmCENH3-RFP could be detected by RT-PCR, direct fluorescence microscopy, and immunostaining with anti-RFP antibody. The expressed wmCENH3-RFP was localized to nuclei as dotted patterns, indicating its targeting to wheat centromeres. Somatic hybridization was performed between wmCENH3-RFP transgenic wheat and transgenic maize that expressed a ZmCENH3-YFP gene to investigate chromosome behaviors in somatic hybrids. Cytological and FISH analyses of somatic hybrid cells showed the formation of micronuclei and lagging chromatin in both somatic hybridizations with or without the wmCENH3-RFP transgene, indicating that ectopically expressed wmCENH3 could not overcome chromosome elimination in wheat/maize somatic hybrids. Immunostaining of wmCENH3-RFP and ZmCENH3-YFP in early stage somatic hybrid cells indicated that both wmCENH3-RFP and ZmCENH3-YFP proteins were expressed, but their binding patterns changed from the commonly observed dotted patterns to diffused ones, suggesting that the inactivation of CENH3 might be a factor for chromosome elimination in wheat/maize somatic hybridization.

Influences of Root Zone Restriction and Nitrogen Nutrition on Hybrid Wheat Growth

To study the physiological effects of small root zonel plants of a hybrid wheat variety (Triticum aestivnmL.cv. Meiyou 4) were grown in small pots (1 litre) or large pots (8 litre) with 1ow nitrogen (50 mg kg-1 soil)and high nitrogen (200 mg kg-1 soil). Restricting root zone decreased dry weight of plants at the stages ofstem elongation and flowering, compared to those of control plants grown in the large pots (P<0.01). Sprayingof 6-benzylaminopurine (50 μmol L-1) increased dry weight of plants and chlorop hyll concentration in leaves.Restriction of root zone decreased the concentrations of total nitrogen, chlorophyll and soluble protein in thefiag leaf and acce1erated senescence of the leaves. Supply of high nitrogen delayed senescence of the fiag leafThe results suggested that the shortage of nutrients, especially nitrogen deficiency was the primary reasonfor the decreased growth of plant in the treatment of root zone restriction.

Filtering for SNPs with high selective constraint augments mid-parent heterosis predictions in wheat(Triticum aestivum L.)

To extend the contemporary understanding into the grain yield heterosis of wheat, the current study investigated the contribution of deleterious alleles in shaping mid-parent heterosis(MPH). These alleles occur at low frequency in the genome and are often missed by automated genotyping platforms like SNP arrays. The deleterious alleles herein were detected using a quantitative measurement of evolutionary conservation based on the phylogeny of wheat and investigations were made to:(1) assess the benefit of including deleterious alleles into MPH prediction models and(2) understand the genetic underpinnings of deleterious SNPs for grain yield MPH using contrasting crosses viz. elite × elite(Exp. 1) and elite × plant genetic resources(PGR;Exp. 2). In our study, we found a lower allele frequency of moderately deleterious alleles in elites compared to PGRs. This highlights the role of purifying selection for the development of elite wheat cultivars. It was shown that deleterious alleles are informative for MPH prediction models: modelling their additive-by-additive effects in Exp. 1 and dominance as well as associated digenic epistatic effects in Exp. 2 significantly boosts prediction accuracies of MPH. Furthermore,heterotic-quantitative trait loci's underlying MPH was investigated and their properties were contrasted in the two crosses. Conclusively, it was proposed that incomplete dominance of deleterious alleles contributes to grain yield heterosis in elite crosses(Exp. 1).

小麦光温敏核雄性不育系BS366和BS1086杂种一代结实率研究

为了解小麦光温敏核雄性不育系BS366和BS1086的育性恢复状况,评估恢复系人工定向改良对其恢复能力的效果,在不育生态区对以55份定向改良的恢复系和33份非改良恢复系(常规小麦)为父本配制的杂种一代的结实率进行了分析。结果表明,BS366和BS1086杂种一代结实率变化范围为15.42%~140.34%和20.28%~119.07%(国际法),平均结实率分别为73.02%和72.21%,二者差异不显著,说明2份母本的育性恢复能力差异不显著。BS366和BS1086杂种一代结实率主要分布于40%~110%和60%~100%间,BS1086杂种一代结实率分布更为集中。BS366和BS1086与改良父本的杂种一代平均结实率分别为84.45%和78.97%,与非改良父本的杂种一代平均结实率分别为53.97%和60.95%,改良父本的平均恢复力高于非改良父本,表明定向改良有利于提高恢复系的恢复力。BS366和BS1086与相同父本的杂种一代结实率差异在-41.66%~61.93%之间,表明相同父本对不同母本的育性恢复力存在差异。BS366和BS1086与相同改良父本的杂种一代中有61.82%的结实率差异分布于-10%~20%之间,与相同非改良父本的杂种一代中有51.52%的结实率差异在-30%~0%之间,表明同一改良父本对不同母本的育性恢复力差异小于非改良父本。BS366与14份父本、BS1086与7份父本的杂种一代结实率高于对照,其中父本14YH261、14YH551、SD036与2份母本杂种一代的结实率均高于对照,说明具有可用恢复力的父本不仅数量极少,而且对不同母本的恢复力存在较大差异。杂种一代主茎穗的平均结实率极显著大于分蘖穗。因此,建议对不同母本分别开展强恢复力的恢复系筛选,并以中选强恢复系为亲本进行定向改良,有效增加杂种一代结实率达对照水平的组合数量,为获得更多强优势杂交组合奠定基础。

新疆冬麦区AL型三系杂交小麦亲本配合力、杂种优势和聚类分析

为了解新疆AL型三系杂交小麦亲本间配合力及其杂种优势关系,利用稳定不育系8份,恢复力强的恢复系9份,按照NCⅡ不完全双列杂交(8×9)设计配制72个F 1杂交组合,对亲本及杂交组合的7个农艺性状进行配合力效应和杂种优势分析,再根据亲本性状和一般配合力划分杂种优势类群。结果表明,三系小麦杂交组合中普遍存在产量和产量性状杂种优势,针对强优势组合的亲本选择,双亲之一一般配合力(GCA)或双亲GCA之和为正值且相对较大;相关性分析表明,中亲优势与父本和母本GCA值之和呈极显著正相关,父本和母本的GCA相关性大于特殊配合力(SCA)相关性。针对6个性状的GCA效应值和性状表型值分别进行聚类分析表明,配合力距离远的亲本组配可能出现强优势杂交组合的几率较大,性状表型值距离较远的两个亲本同一性状之间的优势互补也可以在后代中表现出较强的杂种优势。将17个亲本划分为4个和5个类群,为后续AL型杂交小麦强优势杂交组合的配制提供了依据。

不同遗传背景亲本及其杂交种对田间出苗率的影响

为了研究细胞质不同亲本及其杂交种对田间出苗率的影响,以29个AL型不育系和25个恢复系为亲本材料配制了双列杂交组合,以“同母多父”和“同父多母”的方式,对杂交种和亲本的田间出苗率进行比较分析。结果表明,细胞质遗传背景不同的恢复系、保持系、杂交种之间田间出苗率差异不显著。杂交种与双亲的田间出苗率间呈显著正相关,田间出苗率高的亲本所配置杂交种田间出苗率表现出较高杂种优势。杂交种田间出苗率应该作为优异亲本的重要指标得到重视。

杀雄剂CH1对冬小麦雄性不育的效应研究

为探讨化学杀雄剂CH1对冬小麦雄性不育的诱导效果及其与乙烯利的互作效应、筛选CH1最佳使用剂量和表面活化剂组合,用6个CH1剂量水平、7种表面活化剂和3种浓度的乙烯利进行不同配伍组合,对不同组合处理下3个小麦品种的农艺性状、雄性不育率和饱和授粉结实率进行了分析。结果表明:(1)在15~30 g·hm^(-2)剂量下,CH1可诱导3个品种雄性不育率达95%以上,说明CH1具有诱导小麦雄性不育的作用;随CH1剂量的增加,3个品种的饱和授粉结实率均呈下降趋势,其中20~30 g·hm^(-2)处理的饱和授粉结实率明显偏低,推测雌蕊受到了一定的伤害;(2)观察花药和雌蕊发育情况,发现未喷施CH1的植株花药大且开裂,羽毛状柱头较大,而CH1处理的不育株花药瘦小,呈剑状,不开裂,羽毛状柱头较小;(3)随着CH1剂量的增加,3个品种均表现出株高逐渐降低和抽穗期延迟的现象,CH1对旗叶的药害反应因品种不同存在差异;(4)CH1剂量为10 g·hm^(-2)时,与其他表面活化剂相比,NE1820对普冰151的旗叶伤害较轻,对株高无明显抑制作用,可提高饱和授粉结实率;(5) CH1剂量为15 g·hm^(-2)时,添加2种浓度乙烯利后,3个品种的株高比未添加乙烯利降低,抽穗期延迟,其中添加5 mL·L^(-1)乙烯利后3个品种均能达到100%雄性不育,并且饱和授粉结实率相比未添加乙烯利平均高7%左右。因此,CH1采用15 g·hm^(-2)剂量,配伍1%NE1820和5 mL·L^(-1)乙烯利可诱导小麦产生完全的雄性不育,且获得较高的授粉结实率,可作为杂交小麦制种候选方案进一步研究与利用。

纤毛鹅观草-普通小麦高抗条锈病多年生属间杂种F1的创制及鉴定

本研究对鹅观草属(Roegneria C.Koch.)13个物种29份材料进行条锈病田间鉴定和抗条锈病基因检测,将筛选的抗病材料与小麦进行人工属间杂交,并对属间杂种F_(1)进行形态学、细胞遗传学及小麦条锈病抗性检测,结果显示:82.76%的材料在田间对条锈病表现中抗以上的抗性,且均含有5个以上的已知抗条锈病基因的等位基因,但仍可能存在条锈病抗性新基因;筛选到的一份高抗条锈病的纤毛鹅观草(Roegneria ciliaris[Trin.]Nevski)ZY11004-R,将其与5个普通小麦(Triticum aestivum L.)品种进行人工属间杂交,通过胚拯救的方式成功获得了纤毛鹅观草-普通小麦CSph2a属间杂种F_(1);杂种F_(1)体细胞染色体条数为35条(基因组组成为StYABD),花粉母细胞减数分裂I中期染色体多为单价体,形态特征处于两亲本之间,但在生活习性上获得多年生的性状,并表现出高抗条锈病。