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991.
‘小红玫瑰’葡萄是源自于‘小白玫瑰’的突变品种,二者都是优良的酿酒葡萄品种,但其果实颜色变异的分子机理尚不清楚。用12对SSR(Simple sequence repeats)荧光标记特征引物对两品种进行分析,结果表明这些位点在二者之间无差别。对色泽变异决定基因Vvmyb A1的基因型进行分析,‘小白玫瑰’仅检测到含有插入逆转座子Gret1(grapevine retrotransposon 1)的VvmybA1a,说明其为VvmybA1a/VvmybA1a纯合体;而‘小红玫瑰’检测到了Vvmyb A1a和残留Gret1 3′-LTR(long terminal repeat)的VvmybA1b,说明其为VvmybA1a/VvmybA1b的杂合体。花色苷合成相关基因的表达分析表明,VvmybA1、UFGT、F3′5′H、CHS、GST和OMT在‘小红玫瑰’及有色对照品种‘黑比诺’中大量表达,而在‘小白玫瑰’和无色对照品种‘白比诺’中几乎不表达。通过HPLC–ESI–MS/MS对花色苷主要成分进行测定,结果表明矢车菊素3–O–葡萄糖苷(CyG)、矢车菊素3,5–O–双葡萄糖苷(Cy2G)、飞燕草素3–O–葡萄糖苷(DpG)、锦葵色素3–O–葡萄糖苷(MvG)、芍药色素3–O–葡萄糖苷(PnG)和矮牵牛色素3–O–葡萄糖苷(PtG)等6种花色苷在有色品种‘小红玫瑰’和‘黑比诺’果皮中的含量均显著高于无色品种,花葵素3–O–葡萄糖苷(Pg G)、花葵素3,5–O–双葡萄糖苷(Pg2G)在有色/无色品种间无显著差异,且含量很低。说明‘小红玫瑰’的着色是由于转录因子基因Vvmyb A1及其调控结构基因的表达引起的,而无功能的VvmybA1a等位基因突变为有功能的VvmybA1b等位基因是其果皮颜色变异的遗传学原因。  相似文献   
992.
Functional stay‐green is generally regarded as a desirable trait of varieties in major crops including maize. In this study, we used an F3:4 recombinant inbred line population with 165 lines from a cross between a stay‐green inbred line (Zheng58) and a model inbred line (B73) using 211 polymorphic simple sequence repeat markers to map quantitative trait loci for three stay‐green‐associated parameters, chlorophyll content, photosystem II photochemical efficiency and stay‐green area, at maturity stage, detected a total of 23 quantitative trait loci (QTL) on nine chromosomes. Single QTL explained 3.7–13.5% of the phenotypic variance. Additionally, we validated some important stay‐green QTL using a heterogeneous inbred family approach and found that the stay‐green‐associated parameters were significantly correlated with the plant yield. This study may contribute to a better insight into the regulatory mechanism behind leaf stay‐green in maize and a novel development of elite maize varieties with delayed leaf senescence through molecular marker‐assisted selection.  相似文献   
993.
以京秀、早黑宝、白鸡心、克伦生4个鲜食葡萄品种的1年生枝为试材,通过对生根促进剂吲哚丁酸浓度的筛选试验,选择吲哚丁酸(2 000mg/L)对葡萄硬枝进行扦插成活率的影响试验。结果表明:克伦生、白鸡心生根情况较好,早黑宝居中,京秀最差。  相似文献   
994.
Soybean lodging can result in serious yield reduction. Detecting the quantitative trait loci (QTL) associated with lodging tolerance for their further application in marker‐assisted selection (MAS) has the potential to enhance soybean breeding efficiency. In this study, a genome‐wide association analysis (GWAS) was performed to identify soybean accessions that could potentially be used to produce lodging‐tolerant varieties, based on the comprehensive evaluation of lodging scores (LS) obtained for the parental cultivar “Tokachi nagaha” and its 137 derived cultivars. Results showed that genotype, environment and genotype × environment interaction significantly influenced LS. Of the 31 significant SNPs identified, 22 were consistently detected in two or more environments and 27 SNPs were located in or close to agronomically important QTL mapped by linkage analysis. Best linear unbiased predictors (BLUPs) of LS tend to decrease with the elite alleles contained by accessions increasing. Some excellent accessions, with lower BLUPs and Di (stability coefficients) values and more elite alleles, were selected. This study contributed to understand the genetic mechanism of lodging, providing genetic and phenotypic information for MAS.  相似文献   
995.
为给茭白与鸭共作系统中适宜放养鸭密度提供参考依据,本研究通过大田试验,比较了茭白单作、茭白田放鸭300、375、450只/hm~2条件下茭白的生物学性状、产量和品质。结果表明:茭鸭共作能显著提高茭白后期叶片数、干物重及产量,并延缓茭白后期叶片衰败。放鸭密度从375只/hm~2增加至450只/hm~2时,茭白后期叶片衰败加快,且茭白产量不再增加。茭鸭共作显著提高茭白蛋白质、维生素C和氨基酸含量。茭鸭共作系统灌溉养殖池塘富营养化水4500 m~3/hm~2时,输入的N、P、K相当于99.75 kg尿素、38.25 kg过磷酸钙和83.55 kg氯化钾的养分含量。本试验条件下,茭白常规种植密度27795株/hm~2,田间适宜放鸭密度为375只/hm~2,可显著提高茭白产量及品质。  相似文献   
996.
Pre-harvest sprouting (PHS) causes significant yield loss and degrade the end-use quality of wheat, especially in regions with prolonged wet weather during the harvesting season. Unfortunately, the gene pool of Triticum durum (tetraploid durum wheat) has narrow genetic base for PHS resistance. Therefore, finding out new genetic resources from other wheat species to develop PHS resistance in durum wheat is of importance. A major PHS resistance QTL, Qphs.sicau-3B.1, was mapped on chromosome 3BL in a recombinant inbred line population derived from ‘CSCR6’ (Triticum spelta), a PHS resistant hexaploid wheat and ‘Lang’, a PHS susceptible Australian hexaploid wheat cultivar. This QTL, Qphs.sicau-3B.1, is positioned between DArT marker wPt-3107 and wPt-6785. Two SCAR markers (Ph3B.1 and Ph3B.2) were developed to track this major QTL and were used to assay a BC2F8 tetraploid population derived from a cross between the durum wheat ‘Bellaroi’ (PHS susceptible) and ‘CSCR6’ (PHS resistant). Phenotypic assay and marker-assisted selection revealed five stable tetraploid lines were highly PHS resistant. This study has successfully established that PHS-resistance QTL from hexaploid wheat could be efficiently introgressed into tetraploid durum wheat. This tetraploid wheat germplasm could be useful in developing PHS resistant durum cultivars with higher yield and good end-use quality.  相似文献   
997.

Context

Species distribution models (SDM) establish statistical relationships between the current distribution of species and key attributes whereas process-based models simulate ecosystem and tree species dynamics based on representations of physical and biological processes. TreeAtlas, which uses DISTRIB SDM, and Linkages and LANDIS PRO, process-based ecosystem and landscape models, respectively, were used concurrently on four regional climate change assessments in the eastern Unites States.

Objectives

We compared predictions for 30 species from TreeAtlas, Linkages, and LANDIS PRO, using two climate change scenarios on four regions, to derive a more robust assessment of species change in response to climate change.

Methods

We calculated the ratio of future importance or biomass to current for each species, then compared agreement among models by species, region, and climate scenario using change classes, an ordinal agreement score, spearman rank correlations, and model averaged change ratios.

Results

Comparisons indicated high agreement for many species, especially northern species modeled to lose habitat. TreeAtlas and Linkages agreed the most but each also agreed with many species outputs from LANDIS PRO, particularly when succession within LANDIS PRO was simulated to 2300. A geographic analysis showed that a simple difference (in latitude degrees) of the weighted mean center of a species distribution versus the geographic center of the region of interest provides an initial estimate for the species’ potential to gain, lose, or remain stable under climate change.

Conclusions

This analysis of multiple models provides a useful approach to compare among disparate models and a more consistent interpretation of the future for use in vulnerability assessments and adaptation planning.
  相似文献   
998.
为强化对国际航行船舶的检疫监管,降低植物有害生物传入风险,本文对"十二五"期间连云港口岸国际航行船舶截获植物有害生物的情况进行了统计,掌握了截获有害生物的种类,分析了影响截获的主要因素,并提出相应的检疫对策。  相似文献   
999.
番茄新品种‘辽粉2号’为无限生长类型一代杂种。生长势强,抗黄化曲叶病毒病、烟草花叶病毒病、叶霉病、根结线虫病等。果实扁圆形,粉红色,有绿肩,平均单果质量142 g。可溶性固形物含量4.7%。产量高,留3穗果平均产量可达109.1 t·hm~(-2)。果实口感好,硬度中等,耐贮运性好。  相似文献   
1000.
吴璐瑶  金华  陈燕妮  张碧涵  王玲 《园艺学报》2017,44(Z2):2717-2718
 ‘婷蝶’是从溪荪(Iris sanguinea Donn ex Horn.)实生后代中选育出的切花新品种。2年生花期株高127 cm,冠幅55 ~ 65 cm,花葶粗壮而整齐,高109 ~ 114 cm,粗0.48 cm。每株丛花葶数25 ~ 30,单葶花朵2 ~ 3朵,花径11 cm。花期5—6月,连续花期22 d左右,在中国北方地区可露地越冬。  相似文献   
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