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91.
Wild barley (Hordeum vulgare ssp. spontaneum) and landraces are important sources of resistance to biotic and abiotic stresses since they possess wide genetic diversity that may be missing in current elite varieties. In this study, we evaluated a set of 57 barley introgression lines divided in groups depending on the expected levels of introgression (50, 25, and 12.5 %) from one Hordeum spontaneum accessions (Hsp 41-1) and on those (50 and 25 %) from a second (Hsp 41-5); in both cases the 25 % level was represented by two groups depending on the other parent. The two H. spontaneum accessions have been used as the best sources of drought tolerance in the ICARDA barley-breeding program. Graphical genotyping and genetic diversity analysis were used to examine the relative contribution of H. spontaneum and the extent of genetic differences among the 57 lines using 74 microsatellite markers that cover 941 cM of the barley genome. The average proportion of the genome containing H. spontaneum alleles in each group was of 44.5 %, group 1; 24.6 %, group 2; 21.6 %, group 3; 45.4 %, group 4; 19 %, group 5; 15.5 %, group 6 and 11.4 %, group 7. Introgression lines in group 1 and 4, with the highest observed introgression with Hsp 41-1 and Hsp 41-5, showed higher grain yield and better agronomic performance under field conditions in Breda and Khanaser, i.e., the two most stressed environments in which the groups were phenotyped, indicating the usefulness of using H. spontaneum as a source of chromosomal linkage blocks important for improved drought tolerance. However, more extensive genome coverage will be needed to identify the specific chromosomal regions associated with superior performance under extreme drought. 相似文献
92.
Claire Erlacher-Reid Allison D. Tuttle Salvatore Frasca Jr. 《Journal of aquatic animal health》2013,25(3):171-177
Abstract An aquarium-maintained male California moray Gymnothorax mordax had a symmetrical enlargement of the soft tissues of the head dorsal to the cranium for 2 years prior to its death. This individual was anesthetized for radiographic and ultrasonographic examination of the lesion, and blood was collected for plasma biochemical analytes and lipid profiles. Radiographs and ultrasound of the lesion demonstrated a symmetrical and homogeneous soft tissue density that was consistent with adipose tissue. Plasma cholesterol and triglyceride values appeared elevated; therefore, the animal's diet was amended to decrease fat consumption. Triglyceride values decreased after dietary changes were made; however, values for cholesterol, high-density lipoproteins, and low-density lipoproteins fluctuated but remained largely unchanged. Histopathological assessment of the lesion revealed localized xanthogranulomatous inflammation of hypodermal adipose tissue. The etiology of the lesion in this animal was never determined. This paper describes the first documented case of localized xanthogranulomatous panniculitis in a California moray and demonstrates the need for additional research on specific dietary requirements, species-specific physiological differences, and lesions involving the adipose tissue of morays in comparison with other teleost species. Received September 16, 2011; accepted February 9, 2012 相似文献
93.
94.
Salvatore Luciano Cosentino Mariadaniela MantineoGiorgio Testa 《Industrial Crops and Products》2012,36(1):329-342
In the framework of the E.U. project Fair CT 96-1913 “Environmental studies on sweet and fibre sorghum, sustainable crops for biomass and energy”, a research has been carried out with the aim to study the water and nitrogen balance and determine the critical N dilution curve of sweet sorghum cv. Keller. A field experiment was performed, where three irrigation treatments (I0 = dry control, I50 = 50% ETm restoration, I100 = 100% ETm restoration) and four nitrogen fertilization levels (N0 = no nitrogen control, N60 = 60 kg ha−1, N120 = 120 kg ha−1; N180 = 180 kg ha−1) were studied. The final yield was significantly affected by the amount of water distributed but not by the nitrogen level. The treatments watered up to crop establishment (I0) produced, in the average, 7.5 t ha−1 of dry matter, against 21.1 and 27.1 t ha−1 of I50 and I100, respectively. The crop determined a great reduction in nitrate concentration of soil water, irrespective of nitrogen supplied. The variation between N output and input (Δ) was negative in N0, N60 and N120 and positive in N180. The critical value of nitrogen uptake change in relation to the water availability. The amount of nitrogen supplied did not determine significant differences upon WUE. The crop seems to have a great potentiality in Mediterranean environment in terms of yield production. 相似文献
95.
96.
Alessandro Tondelli Enrico Francia A. Visioni J. Comadran A. M. Mastrangelo T. Akar A. Al-Yassin S. Ceccarelli S. Grando A. Benbelkacem F. A. van Eeuwijk W. T. B. Thomas A. M. Stanca I. Romagosa N. Pecchioni 《Euphytica》2014,197(1):73-86
Multi-environment trials represent a highly valuable tool for the identification of the genetic bases of crop yield potential and stress adaptation. A Diversity Array Technology®-based barley map has been developed in the ‘Nure’ × ‘Tremois’ biparental Doubled Haploid population, harbouring the genomic position of a gene set with a putative role in the regulation of flowering time and abiotic stress response in barley. The population has been evaluated in eighteen location-by-year combinations across the Mediterranean basin. QTL mapping identified several genomic regions responsible for barley adaptation to Mediterranean conditions in terms of phenology, grain yield and yield component traits. The most frequently detected yield QTL had the early flowering HvCEN_EPS2 locus (chromosome 2H) as peak marker, showing a positive effect from the early winter parent ‘Nure’ in eight field trials, and explaining up to 45.8 % of the observed variance for grain yield. The HvBM5A_VRN-H1 locus on chromosome 5H and the genomic region possibly corresponding to PPD-H2 on chromosome 1H were significantly associated to grain yield in five and three locations, respectively. Environment-specific QTLs for grain yield, and clusters of yield component QTLs not related to phenology and or developmental genes (e.g. on chromosome 4H, BIN_09) were observed as well. The results of this work provide a valuable source of knowledge and tools for both explaining the genetic bases of barley yield adaptation across the Mediterranean basin, and using QTL-associated markers for MAS pre-breeding and breeding programmes. 相似文献
97.
Anna Fontana Diana E. Debreczeni Giuliana Albanese Salvatore Davino Ricardo Flores Luis Rubio 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(3):607-613
The evolution of citrus tristeza virus (CTV) from outbreaks occurred in Calabria, Italy, was compared with that of CTV outbreaks reported previously in another two proximal Italian regions, Sicily and Apulia. Examination of four genomic regions (genes p20, p25 and p23, and one fragment of open reading frame 1) showed two recombination events, and phylogenetic analysis disclosed two divergent CTV groups in Calabria: one formed by severe and the other by mild isolates. This analysis, together with others involving population genetic parameters, revealed a low migration rate of CTV between the three Italian regions, as well as significant differences in selective pressures, epidemiology and demography, all affecting the genetic structure of CTV populations. 相似文献
98.
J. Comadran J. R. Russell F. A. van Eeuwijk S. Ceccarelli S. Grando M. Baum A. M. Stanca N. Pecchioni A. M. Mastrangelo T. Akar A. Al-Yassin A. Benbelkacem W. Choumane H. Ouabbou R. Dahan J. Bort J.-L. Araus A. Pswarayi I. Romagosa C. A. Hackett W. T. B. Thomas 《Euphytica》2008,161(1-2):35-45
Identifying barley genomic regions influencing the response of yield and its components to water deficits will aid in our understanding of the genetics of drought tolerance and the development of more drought tolerant cultivars. We assembled a population of 192 genotypes that represented landraces, old, and contemporary cultivars sampling key regions around the Mediterranean basin and the rest of Europe. The population was genotyped with a stratified set of 50 genomic and EST derived molecular markers, 49 of which were Simple Sequence Repeats (SSRs), which revealed an underlying population sub-structure that corresponded closely to the geographic regions in which the genotypes were grown. A more dense whole genome scan was generated by using Diversity Array Technology (DArT®) to generate 1130 biallelic markers for the population. The population was grown at two contrasting sites in each of seven Mediterranean countries for harvest 2004 and 2005 and grain yield data collected. Mean yield levels ranged from 0.3 to 6.2 t/ha, with highly significant genetic variation in low-yielding environments. Associations of yield with barley genomic regions were then detected by combining the DArT marker data with the yield data in mixed model analyses for the individual trials, followed by multiple regression of yield on markers to identify a multi-locus subset of significant markers/QTLs. QTLs exhibiting a pre-defined consistency across environments were detected in bins 4, 6, 6 and 7 on barley chromosomes 3H, 4H, 5H and 7H respectively. 相似文献
99.
QTLs for chlorophyll and chlorophyll fluorescence parameters in barley under post-flowering drought 总被引:6,自引:1,他引:5
Peiguo Guo Michael Baum Rajeev K. Varshney Andreas Graner Stefania Grando Salvatore Ceccarelli 《Euphytica》2008,163(2):203-214
Drought is one of the major factors limiting barley yields in many developing countries worldwide. The identification of molecular
markers linked to genes controlling drought tolerance in barley is one way to improve breeding efficiency. In this study,
we analyzed the quantitative trait loci (QTL) controlling chlorophyll content and chlorophyll fluorescence in 194 recombinant
inbred lines (RILs) developed from the cross between the cultivar ‘Arta’ and Hordeum spontaneum 41-1. Five traits, chlorophyll content, and four chlorophyll fluorescence parameters, namely initial fluorescence (Fo), maximum fluorescence (Fm), variable fluorescence (Fv), and maximum quantum efficiency of PSII (Fv/Fm) which are related to the activity of the photosynthetic apparatus, were measured under well-watered and drought stress conditions
at post-flowering stage. QTL analysis identified a total of nine and five genomic regions, under well-watered and drought
stress conditions, respectively, that were significantly associated with the expression of the five target traits at post-flowering
stage. No common QTL was detected except one for chlorophyll content, which was identified in both growth conditions, demonstrating
that the genetic control of the expression of the traits related to photosynthesis differed under different water conditions.
A QTL for Fv/Fm, which is related to the drought tolerance of photosynthesis was identified on chromosome 2H at 116 cM in the linkage map
under drought stress. This QTL alone explained more than 15% of phenotypic variance of maximum quantum yield of PSII, and
was also associated with the expression of four other traits. In addition, another QTL for Fv/Fm was also located on the same chromosome (2H) but at 135.7 cM explaining around 9% of the phenotypic variance under drought
conditions. The result presented here suggest that two major loci, located on chromosome 2H, are involved in the development
of functional chloroplast at post-flowering stage for drought tolerance of photosynthesis in barley under drought stress.
If validated in other populations, chlorophyll fluorescence parameters could be used as selection criteria for drought tolerance. 相似文献
100.
This study provide information on the first occurrence in Italy of the Coleoptera Cerambycidae Chlorophorus annularis (Fabricius, 1787). It is a species naturally and widely distributed in Asia and in oriental tropical and subtropical areas. This cerambyx is a post-harvest pest of bamboo belonging to several genera as Bambusa, Dendrocalamus, Phyllostachys, Sinocalamus, but it can also infest cultivated plants as Citrus spp., Gossypium, Liquidambar spp., Saccharum officinarum L., Vitis spp., and Zea mays L. 相似文献