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1.
【目的】通过比较黄毛草莓和凤梨草莓的2个种间杂种PF(具黄毛草莓浓郁的蜜桃香气)和NF(无蜜桃香气)完熟期果实香气成分的代谢谱,为黄毛草莓蜜桃香气特征成分鉴定及野生草莓优异资源的开发利用提供参考。【方法】采用顶空固相微萃取和气相色谱/质谱联用技术(gas chromatograph tandem mass spectrometer technology,GC-MS),对供试材料的香气成分进行检测。采用偏最小二乘法判别分析(partial least squares discrimination analysis,PLS-DA)模型第一主成分的变量投影重要度(variable importance in the projection,VIP)值和log2FC(Fold Change,FC),结合T-test的P值来筛选差异性代谢物,PF相对于NF,设置阈值VIP>1.0, log2FC>1.0或log2FC<-1.0且P value<0.05,差异代谢物的相对含量采用峰面积归一化法计算,CAS号(Chemical Abstracts Service Registry Number)在https://pubchem.ncbi.nlm.nih.gov 网站查阅。【结果】从检测到的383种总代谢物中筛选出67种差异代谢物,其中58种上调,9种下调,上调幅度较大的差异代谢物为内酯类物质,log2FC排在前3名的依次是(Z)-7-癸烯-5-酸(5.60)、丁位十一内酯(5.33)、δ-癸内酯(5.30),下调幅度较大的差异代谢物为酯类物质,-log2FC排在前3名的依次是肉桂酸乙酯、亚硫酸(-7.19),2-乙基己基异己酯(-6.65)和3-羟基丁酸乙酯(-4.14)。从相对含量来看,酯类在PF(37.69%)中大幅低于NF(57.20%),内酯类在PF(20.91%)中大幅高于NF(6.12%),酮类在PF(15.30%)中略高于NF(9.12%),醇类、醛类、酸类、烯烃类和其他代谢物在PF和NF中的含量相当,NF中相对含量最大的酯是丁酸乙酯(17.92%),PF中相对含量最大的内酯是δ-癸内酯(12.53%),PF相对含量最大的酮与NF相同,均为2-庚酮。【结论】肉桂酸乙酯、丁酸乙酯和3-羟基丁酸乙酯等酯类可能是NF的关键香气成分,(Z)-7-癸烯-5-酸、丁位十一内酯和δ-癸内酯等内酯类可能是形成PF蜜桃香气的关键物质。 相似文献
2.
Iñigo Loureiro María Concepción Escorial María Cristina Chueca 《Pest management science》2023,79(6):2247-2254
BACKGROUND
Cultivated bread wheat (Triticum aestivum L.) spontaneously hybridizes with wild/weedy related Aegilops populations, but little is known about the actual rates at which this hybridization occurs under field conditions. It is very important to provide reliable empirical data on this phenomenon in order to assess the potential crop–wild introgression, especially in the context of conducting risk assessments for the commercialization of genetically modified (GM) wheat, as gene flow from wheat to Aegilops species could transfer into the wild species genes coding for traits such as resistance to herbicides, insects, diseases or environmental stresses.RESULTS
The spontaneous hybridization rates between wheat and A. geniculata and A. triuncialis, which are very abundant in the Mediterranean area, have been estimated for the first time in the northern part of the Meseta Central, the great central plateau which includes the largest area of wheat cultivation in Spain. Hybridization rates averaged 0.12% and 0.008% for A. geniculata and A. triuncialis, respectively. Hybrids were found in 26% of A. geniculata and 5% of A. triuncialis populations, at rates that can be ≤3.6% for A. geniculata and 0.24% for A. triuncialis.CONCLUSION
The detection of Aegilops spp.–wheat hybrids in Aegilops populations indicates that gene flow can occur, although wheat is considered a crop with a low-to-medium risk for transgene escape. These data on field hybridization rates are essential for GM wheat risk assessment purposes. © 2023 Society of Chemical Industry. 相似文献3.
通过对油茶无性系及其半同胞子代、自交子代和杂交子代4种不同群体的产量结构、产量频率分布、产量构成等产量性状进行系统深入的研究,探索4种群体及其优良林分的结实特性和产量规律,为油茶杂交子代,优良家系和无性系等良种的生产应用和栽培技术、以及进一步开展杂交和选择育种研究积累了必要的技术和理论知识. 相似文献
4.
以杂交鹅掌楸的叶片、叶柄、无菌苗的茎段及其芽基部切段为外植体,进行愈伤组织途径的器官发生及不定芽途径的直接器官发生培养。结果表明,多种外植体在诱导培养基上均能脱分化产生愈伤组织,其中无菌苗芽基部具有最高的愈伤组织诱导率。愈伤组织在MS 6-BA 2.0 mg.L-1 NAA 0.5 mg.L-1和MS 6-BA 4.0 mg.L-1 NAA 0.5 mg.L-1的分化培养基上能分化出不定芽。部分外植体在MS 6-BA 4.0 mg.L-1 NAA 0.5 mg.L-1的分化培养基上直接分化产生不定芽。器官发生途径再生体系的建立为抗逆基因工程等工作奠定了基础。 相似文献
5.
Pei‐Yi Wang Meng Xiang Min Luo Hong‐Wu Liu Xiang Zhou Zhi‐Bing Wu Li‐Wei Liu Zhong Li Song Yang 《Pest management science》2020,76(8):2746-2754
6.
Alexander G. Kramer Boris Gomelsky Jeffrey L. Warner Noel D. Novelo Brandylyn L. Thomas 《Aquaculture Research》2020,51(7):2824-2830
The purpose of this study was to investigate reproductive ability of backcross triploid koi (Cyprinus carpio L.) × goldfish (Carassius auratus L.) hybrids. These triploids have been obtained by crossing of F1 hybrid females producing diploid eggs with males of parental species. Triploid hybrid females, when crossed with goldfish or koi males, produced mostly aneuploid fish with ploidy range from approximately 2.2n–3.2n with a mean value 2.5n; some fish in crosses of triploid females with koi males were tetraploid (4.0n). Since analysed fish had in their genomes one haploid set from parental males, the data indicate that triploid hybrid females mostly produced aneuploid eggs with ploidy range from approximately 1.2n–2.2n and a mean ploidy around 1.5n while some eggs were triploid. Triploid hybrid males were completely sterile and have not released any sperm after hormonal injection. Despite their low viability, some aneuploid fish obtained from triploid hybrid females were raised in indoor recirculating systems until the age of 2 years and their reproductive ability has been evaluated. One aneuploid female with ploidy 2.1n produced larvae with ploidy range from 2.9n to 3.4n with a mean ploidy of 3.1n when crossed with a koi male; about 60% of obtained larvae had ploidy from 3.0n to 3.2n. These data indicate that this female produced mostly eggs with unreduced ploidy level. 相似文献
7.
The salt‐sensitive Glycine max N23674 cultivar, the salt‐born Glycine soja BB52 population, and their hybrid 4076 strain (F5) selected for salt tolerance generation by generation were used as the experimental materials in this study. First, the effects of NaCl stress on seed germination, tissue damage, and time‐course ionic absorption and transportation were compared. When qualitatively compared with seed germination appearance in culture dishes, and tissue damages on roots or leaves of seedlings, or quantitatively compared with the relative salt injury rate, the inhibition on N23674 was all the most remarkable. After the exposure of 140 mm NaCl for 1 h, 4 h, 8 h, 12 h, 2 days and 4 days, the content of Cl? gradually increased in the roots and leaves of seedlings of BB52, 4076 and 23674. Interestingly, the extents of the Cl? rise in roots of the three experimental soybean materials were BB52 > 4076 > N23674, whereas those in leaves were just on the contrary. Secondly, by using the scanning ion‐selective electrode technique (SIET), fluxes of Na+ and Cl? in roots and protoplasts isolated from roots and leaves were also investigated among the three experimental soybean materials. After 140 mm NaCl stress for 2, 4 and 6 days, and when compared with N23674, slighter net Cl? influxes were observed in root tissue and protoplasts of roots and leaves of BB52 and 4076 seedlings, especially at the cellular protoplast level. The results indicate that with regard to the ionic effect of NaCl stress, Cl? was the main determinant salt ion for salt tolerance in G. soja, G. max and their hybrid, and the difference in their Cl?/salt tolerance is mainly attributed to the capacity of Cl? restriction to the plant above‐ground parts such as leaves. 相似文献
8.
Gabriel Amar‐Basulto Fabiola Lafarga‐De la Cruz Patricia Iturra‐Constant Cristian Gallardo‐Escárate 《Aquaculture Research》2011,42(10):1460-1466
Evidence of hybridization in Haliotis has been mainly supported by hatchery experiences and collection of wild hybrid abalones among several species from natural populations worldwide. However, despite the importance to understand the role of the hybridization process through Haliotidae evolution, and also its impact on the abalone aquaculture, genetic studies in hybrid abalones have been poorly developed. Herein, cytogenetic approach allows studying the genetic conformation in hybrid organisms at the chromosome level. This paper reports a quantitative karyotype analysis in Haliotis rufescens, Haliotis discus hannai and their interspecific hybrid. Thus, to characterize chromosome pairs and establish cytogenetic comparisons, chromosome banding with distamycin‐A/4,6‐diamidino‐2‐phenylindole fluorochromes and morphologic measurements were performed. The results showed that the hybrids are successfully viable and their karyotypes evidenced a conservative chromosome number of 2n=36. The karyo‐idiogram showed a high correspondence in chromosome pair morphology among the hybrids and their parental species, except for a single heteromorphic pair that corresponds to the chromosome 16 from H. rufescens andH. d. hannai respectively. The implications of the abalone hybrid viability derived from its chromosome composition are discussed. 相似文献
9.
本实验对鲫(Carassius auratus,♀)×禾花鱼(Procypris merus,♂)的杂交进行了研究,并比较分析杂交子一代(F1代)及其亲本的形态特征.结果显示:杂交获得杂种F1的受精率为92.5%、孵化率为89.3%,成活率82.9%.6月龄F1代7项测定的可数性状均偏向母本;可量性状中F1有5项偏向母... 相似文献
10.
为研究不同品种杂种落叶松针叶内抗氧化酶活性的差异,用紫外分光光度法对日本落叶松、兴安落叶松和长白落叶松的杂交后代,共2代7个家系的杂种落叶松针叶内的过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)的活性及其差异进行比较分析。结果表明:2代7个家系杂种落叶松针叶内的CAT、POD和SOD的活性差异极显著(P<0.01),F1代CAT、SOD的活性普遍高于F2代,POD活性低于F2代。在抗氧化酶方面,F1代杂种优势高于F2代,F1代日3×兴2、F2代日12×兴9等具有较好的潜在抗虫性;结合其他抗虫生理指标,该研究结果在选育落叶松抗虫品种过程中有参考价值。 相似文献