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Oz Barazani Azat Atayev Bakhtiyor Yakubov Vladimir Kostiukovsky Konstantin Popov Avi Golan-Goldhirsh 《Genetic Resources and Crop Evolution》2003,50(4):383-389
Seedlings of Pistacia vera L. developed from seeds of two separate populations in Turkmenistan, Kepele and Agachli, were evaluated for their growth potential and genetic polymorphism. Plant growth rate as well as random amplified polymorphic DNA (RAPD) analysis showed distinct differences between the two populations. In plant height growth rate, 17 Agachli accessions were 1.3 times higher on average than that of 10 accessions of Kepele (significant at p = 0.046) and 1.2 times higher for trunk diameter growth rate (p = 0.062). Cluster analysis divided most accessions into two main genetic groups according to their geographic origin. The Agachli group was further divided into two subgroups. One Kepele accession (K4), was genetically different from the rest and clustered on a separate outgroup. Two Agachli accessions (A12 and A17) were outside the two main populations clusters. Accessions K9 and K10 from Kepele were exceptional and were clustered in each of the two Agachli's subgroups, indicating a close genetic relationship between the two populations. In addition, high similarity values (0.58–1.00) and small genetic distances reflect plausible gene flow between Kepele and Agachli, which are 100 Km apart. Mantel test revealed significant relationship between the RAPD and the morphological traits matrices, pointing to the genetic basis for the measured differences in the growth rate. Growing the accessions on the same plot, under similar conditions enabled the evaluation of genotypic differences. The combination of morphological traits and molecular markers will further assist in preservation of genetic variability and cultivation of useful genotypes of P. vera L. 相似文献
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A.?M.?Ramos-Cabrer S.?Pereira-LorenzoEmail author 《Genetic Resources and Crop Evolution》2005,52(7):879-890
This study is focused in the main chestnut growing areas from north- to south-western Spain. We studied 50 accessions corresponding
to 22 cultivars named by local growers; 11 from Andalucía, 9 from Castilla-León, and 2 from Extremadura. These were compared
with 22 types classified previously in Galicia (82 accessions). Ten morphological traits and five isoenzyme systems were used
to classify them and establish genetic relationships. A lower genetic variability has been found in Extremadura (middle Spain)
and Andalucía (south) than in Galicia (north western) which may be because of the lower importance of the crop in those areas
and the geographic barriers between them. Galicia could be the origin of the types found in Castilla-León, Extremadura, and
south-western Andalucía, and the types found in Central Andalucía were closer to those found in Castilla-León and Extremadura.
Most accessions studied (117/132) could be classified positively, making 37 out of 44 cultivars found from northern to southern
Spain. Three groups of synonymies were found in Castilla-León: ‘Brava’ and ‘Negral’, ‘Gallego’ and ‘Injerto’, and ‘Rapega’
and ‘Verdello’. Most of the Spanish types have been propagated as a principal clone. Variability within the types is important
and must be considered to select the best clones as cultivars. 相似文献
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本文初步研究了攀枝花市不同年龄与生境的麻疯树老树,分析了老树特征与衰老的环境诱导结构限制现象。结果表明:(1)麻疯树衰老树体相对地径(16 cm~62 cm)、树龄(15 a~41 a)、冠幅(3 m×3 m~8.5 m×8.5m)、高度(2 m~6.96 m)较大,一级枝较大,有一定比例的枯死枝;(2)新梢小(枝径0.7 cm~1.12 cm;长度7 cm~28 cm之间),生长量低,萌生枝稀少,生殖枝比例偏低(趋近于30%以下);(3)单枝坐果量低(0~3个),干果重量1.65 g,千粒重490 g,壳比例30%,适合度偏低;(4)生境肥沃时树龄偏大,衰老程度弱,而生境瘠薄时树龄小,衰老程度强烈;(5)不考虑环境异质性,则衰老为树体结构限制的结果,新梢大小小于分支阈值,丧失了树体发育的能力而成为限制生长的因素。综合分析,麻疯树老树指标是分支率,在分支率为1时衰老启动;形态上衰老为环境诱导结构限制的产物,而结构限制可能是衰老的主观因素。 相似文献
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We present here an indicator of soil quality that evaluates soil ecosystem services through a set of 5 subindicators, and further combines them into a single general Indicator of Soil Quality (GISQ). We used information derived from 54 properties commonly used to describe the multifaceted aspects of soil quality. The design and calculation of the indicators were based on sequences of multivariate analyses. Subindicators evaluated the physical quality, chemical fertility, organic matter stocks, aggregation and morphology of the upper 5 cm of soil and the biodiversity of soil macrofauna. A GISQ combined the different subindicators providing a global assessment of soil quality.Research was conducted in two hillside regions of Colombia and Nicaragua, with similar types of land use and socio-economic context. However, soil and climatic conditions differed significantly. In Nicaragua, soil quality was assessed at 61 points regularly distributed 200 m apart on a regular grid across the landscape. In Colombia, 8 plots representing different types of land use were arbitrarily chosen in the landscape and intensively sampled. Indicators that were designed in the Nicaragua site were further applied to the Colombian site to test for their applicability.In Nicaragua, coffee plantations, fallows, pastures and forest had the highest values of GISQ (1.00; 0.80; 0.78 and 0.77, respectively) while maize crops and eroded soils (0.19 and 0.10) had the lowest values. Examination of subindicator values allowed the separate evaluation of different aspects of soil quality: subindicators of organic matter, aggregation and morphology and biodiversity of macrofauna had the maximum values in coffee plantations (0.89; 0.72 and 0.56, respectively on average) while eroded soils had the lowest values for these indicators (0.10; 0.31 and 0.33, respectively).Indicator formulae derived from information gained at the Nicaraguan sites were not applicable to the Colombian situation and site-specific constants were calculated.This indicator allows the evaluation of soil quality and facilitates the identification of problem areas through the individual values of each subindicator. It allows monitoring of change through time and can guide the implementation of soil restoration technologies. Although GISQ formulae computed on a set of data were only valid at a regional scale, the methodology used to create these indices can be applied everywhere. 相似文献
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唐山地区引种宿根花卉的抗旱性研究 总被引:1,自引:0,他引:1
[目的]了解唐山地区引种的7种宿根花卉的抗旱性。[方法]以唐山地区引种的7种宿根花卉为材料,干旱胁迫0、3、6、9、12、15d,观察植株的形态变化,测定电导率、SOD活性、可溶性蛋白质含量。[结果]在干旱胁迫下,7种宿根花卉发生萎蔫的时间不同,萎蔫情况也不同。随着干旱胁迫时间的延长,7种宿根花卉的电导率均呈上升趋势,但上升速度不同。在干旱胁迫下,7种植物体内的SOD活性都呈先升后降趋势,可溶性蛋白质含量在干旱胁迫初期上升,后期下降。[结论]费菜、‘红花’景天、常夏石竹、‘金娃娃’萱草的抗旱能力强,‘罗米莱紫’穗花婆婆纳、‘柯罗粉’美国薄荷的抗旱能力中等,‘革质’亮金光菊的抗旱能力弱。 相似文献
28.
对染色体数分别为40,78,80的多年生野生大豆G.tomentella种花粉进行了光学显微镜和扫描电镜的观察。发现花粉粒的大小随着染色体数目的增加而变大。染色体数目不同,花粉外壁的纹饰也存在明显的差异。 相似文献
29.
应用光学显微镜和扫描电镜对我国木犀科54种植物的花粉形态进行了系统的观察研究。作者在已论述了4属25种植物花粉形态研究结果基础上,本文着重阐述木犀属(Osmanthus)、李榄属(Linociera)、木犀榄属(Olea)、流苏树属(chionanthus)、胶核木属(Myxopyrum)、女贞属(Ligustrum)、茉莉属(Jasminum)和夜花属(Nyctanthus)共29种植物花粉形态及其分类学意义。结果表明,3(拟)孔沟花粉是基本的、原始类型;4,5孔沟花粉是变异的、进化类型。在变异程度大、较进化的类群中,花粉性状具多样化发展趋势。本文同时讨论了李榄属与流苏树属的分并问题。 相似文献
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