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61.
62.
Species that belong to the genus Triticum L. and the genetically related Aegilops L. genus are important genetic and economic resources because they have an evolutionary relationship with the two main agricultural
crops T. aestivum (bread wheat) and T. durum (durum wheat). Therefore, it is important to understand the genetic relationships among the cultivated wheat species and
their wild relatives. The latter have a great role in the improvement of cultivated wheat. Molecular markers are the best
choice and most reliable means to study these relationships accurately. In this study, we compared the efficiency of the biochemical
methods A–PAGE and SDS–PAGE on seed storage proteins and the molecular methods RAPDs and ISSRs to explore the genetic relationships
among seven species of Triticum and 20 Aegilops species. Three phylogenetic trees obtained in this study were compared with available classifications and phylogenetic trees
constructed earlier for these species. It was noted that the tree based on ISSRs data was the most congruent with those classification
and trees. This may be attributed to the fact that ISSRs is more specific, and therefore more reliable. This study is the
first to study genetic relationships among all species studied here using biochemical and molecular techniques. 相似文献
63.
The effects of application method and concentration of gibberellic acid (GA3), paclobutrazol and chlormequat on black iris performance were assessed. Plants (10 cm high, 4 ± 1 leaves) were sprayed with 125, 250, 375 or 500 mg L−1 or drenched with 0.25, 0.5, 1 or 2 mg L−1 GA3. In a second experiment, the plants were sprayed with 100, 250, 500 or 1000 mg L−1 or drenched with 0.25, 0.5, 1 or 2 mg L−1 paclobutrazol. Other plants were sprayed with 250, 500, 1000 or 1500 mg L−1 or drenched with 100, 250, 375 or 550 mg L−1 chlormequat. In each experiment, the control treatment consisted of untreated plants. Results indicated that the tallest plants (37.3 cm) in the GA3 experiment were those sprayed with 250 mg L−1. The most rapid flowering (160 days after planting) occurred when a 375 mg L−1 GA3 spray was used, whereas flowering was delayed to 200 days using 1 mg L−1 GA3 drench. Drenching with 1 mg L−1 GA3 increased height of the flower stalk by 7 cm compared to the control. Though relatively slow to flower, plants drenched with 1 mg L−1 GA3 had long and rigid stalks, which were suitable as cut flowers. Number and characteristics of the sprouts were not affected by GA3. All paclobutrazol sprays resulted in leaf falcation. A 500 or 1000 mg L−1 paclobutrazol spray resulted in severe and undesirable control of plant height, drastic reduction in stalk height and weight, and delayed flowering. Plants drenched with 0.25 or 1 mg L−1 paclobutrazol were suitable as pot plants. Chlormequat reduced plant height only at the highest drench concentration, which also reduced flowering to 70%. No leaf falcation was observed with GA3 or chlormequat. Chemical names: ( ± )-(R*,R*)-beta-((4-chlorophenyl)methyl)-alpha-(1,1,-dimethylethyl)-1H-1,2,4,-triazol-1-ethanol (paclobutrazol); (2-chloroethyl) trimethylammonium chloride (chlormequat). 相似文献
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66.
Mohamed Boukharta Nadia Touil Elmostafa El Fahim Meriame Terta Bachir Kissi Chafiqua Loutfi Mehdi El Harrak My Mustapha Ennaji 《Journal of Equine Veterinary Science》2014
Reported here are the results of antigenic and genetic characterization of equine influenza strains causing local outbreaks reported in Morocco, respectively, in 1997 and 2004. The antigenic and genetic characterizations of the equine influenza virus H3N8 are reported here. The highest similarity between the HA1 nucleotide sequences of A/equine/Nador/1/1997 and those of A/equine/Rome/5/1991 and A/equine/Italy/1199/1992 demonstrate that A/equine/Nador/1/1997 belongs to the European lineage. On the other hand, A/equine/Essaouira/2/2004 and A/equine/Essaouira/3/2004 were classified in the predivergent lineage. The present work emphasizes the importance of a national influenza survey program, which requires a collaborative laboratory network to promote the collection and characterization (antigenic and genetic) of equine influenza viruses in real time. 相似文献
67.
Nadia T. Rubio-Cisneros Octavio Aburto-Oropeza Jason Murray Charlotte E. Gonzalez-Abraham Jeremy Jackson Exequiel Ezcurra 《Human Dimensions of Wildlife》2014,19(1):1-16
This article explores transnational ecosystem services in North America, provided by winter habitat for waterfowl in western Mexico coastal lagoons, and the hunting industry supported by these birds in the United States. This article shows that the number of waterfowl harvested in the United States is related to the abundance of waterfowl wintering in Mexico. On average, this flow of ecosystem services annually yields US$ 4.68 million in hunting stamp sales in the western United States. A demand curve, fitted to duck hunting licenses as a function of stamp price and previous-year waterfowl harvest, estimated US$3–6 million in consumer surplus produced in addition to governmental stamp sales revenue. This strongly suggests that waterfowl wintering habitat in western Mexico is economically valuable to U.S. hunters. Because hunters may benefit substantially from these habitats they may be willing to pay for conservation efforts in western Mexico that can result in transnational benefits received in the United States. 相似文献
68.
Large-scale copy number polymorphism in the human genome 总被引:1,自引:0,他引:1
Sebat J Lakshmi B Troge J Alexander J Young J Lundin P Månér S Massa H Walker M Chi M Navin N Lucito R Healy J Hicks J Ye K Reiner A Gilliam TC Trask B Patterson N Zetterberg A Wigler M 《Science (New York, N.Y.)》2004,305(5683):525-528
The extent to which large duplications and deletions contribute to human genetic variation and diversity is unknown. Here, we show that large-scale copy number polymorphisms (CNPs) (about 100 kilobases and greater) contribute substantially to genomic variation between normal humans. Representational oligonucleotide microarray analysis of 20 individuals revealed a total of 221 copy number differences representing 76 unique CNPs. On average, individuals differed by 11 CNPs, and the average length of a CNP interval was 465 kilobases. We observed copy number variation of 70 different genes within CNP intervals, including genes involved in neurological function, regulation of cell growth, regulation of metabolism, and several genes known to be associated with disease. 相似文献
69.
广州地区禽类隐孢子虫病的初步调查 总被引:7,自引:0,他引:7
采用饱和蔗糖浮卵法,对广州地区5个鸡场,5个鸭场和3个鹅场的隐孢子虫自然感染情况进行了调查,882份鸡的粪样中隐孢子虫卵囊阳性者有124份,其阳性率为74.1%,1004份鸭的粪样中阳性者273份,其阳性率为27.2%,571份鹅的粪样中阳性者为71份,其阳性率为12.4%,根据卵囊形态和大小,卵囊鉴定为贝氏隐孢子虫。 相似文献
70.
Nadia Musco Valeria Maria Morittu Vincenzo Mastellone Anna Antonella Spina Giuseppe Vassalotti Biagio D’Aniello Raffaella Tudisco Federico Infascelli Pietro Lombardi 《Journal of animal physiology and animal nutrition》2021,105(Z1):26-33
A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed. 相似文献