利用花生遗传资源的一种有效途径   总被引：2，自引：0，他引：2  

C.C.Holbrook 《花生学报》2001,30(3):2-8

美国花生基因库中收集了8000多份种质材料，这些种质材料含有丰富的遗传多样性。然而，这些多样性在育种研究中未能得到充分的评价和广泛的应用，为促进整个花生种质库的开发利用，建立了以A.hypogaea为核心的种质，美国花生种质库首先按来源国别分类，然后再根据种质其它信息量及各来源国种质数目分成9个部分，核心种质中的70％采用上述方法获得，依来源国别分类，进而就形态学数据资料进行多变分量分析，对种质聚类，然后从每组中随机抽取10％的样品，因为有一些种质缺乏形态学数据资料，因此，该种质中的29％是通过按来源国别分类后再随机抽取10％的样品方法进行选择的，剩余的1％是一个简单的随机样品，花生核心种质的建立使种质评价方面的研究明显增多，几组研究者已经对核心种质的24个特征进行了评价，针对几种重要的病源，已鉴定出一部分抗源，利用抗花生晚斑病和根结线虫病的数据资料评价了两阶段核心筛选的方法在鉴定整个种质库中抗性的有效性，两项研究明确证实，核心种质法可用以提高种质评价效率。  相似文献   

Progenies of an interspecific hybrid betweenArachis hypogaea and A.stenosperma — pest resistance and molecular homogeneity     

C. Singsit  C. C. Holbrook  A. K. Culbreath  P. Ozias-Akins 《Euphytica》1995,83(1):9-14

Summary Interspecific triploid hybrids were obtained betweenArachis hypogaea L. andA. stenosperma Krapov. and W.C. Gregory by adopting hybridization coupled with rescue of the developing hybrid embryos. Two hexaploid hybrid populations were generated from triploids, somatically doubled (SD) and sexually polyploidized (SP) hexaploids. Microscopic screening for the occurrence of 2n gametes in triploid hybrids was useful to predict the production of spontaneous hexaploids. In order to facilitate maximum intergenomic recombination, the hexaploids were allowed to self for several generations (F₄) in the greenhouse. Prolific vegetative growth, pollen stainability, and seed set were observed to decline with each selfed generation. Individuals of the F₃ generation from the two hexaploid populations were evaluated for resistance to nematode (Meloidogyne arenaria Chitwood, race 1) and late leafspotCercosporidium personatum (Berk. & Curt.) Deighton under greenhouse conditions. Both SD and SP populations performed significantly better than their cultivated parent, Sunbelt Runner, and a susceptible cultivar, Florunner. At the DNA level, no significant differences were detected among hybrid individuals using cDNA clones and RAPD primers polymorphic for the two parents. Seven cDNA clones were used to probe DNA from 17 F₂ individuals and two parents and 45 RAPD primers were used to amplify DNA from 21 F₂ and F₃ individuals. No significant differences in banding patterns were observed among hybrid individuals which suggested that little or no detectable intergenomic recombination had occurred.  相似文献   

A potential role for xylem-phloem interactions in the hydraulic architecture of trees: effects of phloem girdling on xylem hydraulic conductance     

Zwieniecki MA  Melcher PJ  Feild TS  Holbrook NM 《Tree physiology》2004,24(8):911-917

We investigated phloem-xylem interactions in Acer rubrum L. and Acer saccharum Marsh. Our experimental method allowed us to determine xylem conductance of an intact branch by measuring the flow rate of water supplied at two delivery pressures to the cut end of a small side branch. We found that removal of bark tissue (phloem girdling) upstream of the point at which deionized water was delivered to the branch resulted in a decrease (24% for A. rubrum and 15% for A. saccharum) in branch xylem hydraulic conductance. Declines in hydraulic conductance with girdling were accompanied by a decrease in the osmotic concentration of xylem sap. The decrease in xylem sap concentration following phloem girdling suggests that ion redistribution from the phloem was responsible for the observed decline in hydraulic conductance. When the same measurements were made on branches perfused with KCl solution (approximately 140 mOsm kg(-1)), phloem girdling had no effect on xylem hydraulic conductance. These results suggest a functional link between phloem and xylem hydraulic systems that is mediated by changes in the ionic content of the cell sap.  相似文献   

Parasites of feral cats from southern Tasmania and their potential significance   总被引：2，自引：1，他引：1  

TC MILSTEIN  JM GOLDSMID 《Australian veterinary journal》1997,75(3):218-219

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Equine piroplasmosis: production of antigens for the complement-fixation test   总被引：5，自引：0，他引：5  

W M Frerichs  A A Holbrook  A J Johnson 《American journal of veterinary research》1969,30(8):1337-1341

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Neuroaxonal Dystrophy Associated with Cerebellar Dysfunction in a 5-Month-Old Pony of the Americas Colt     

M.M. Brosnahan  T.C. Holbrook  J.W. Ritchey 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(6):1303-1306

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Evaluation of Efficacy of Mineral Oil,Charcoal, and Smectite in a Rat Model of Equine Cantharidin Toxicosis     

H.J. Qualls  T.C. Holbrook  L.L. Gilliam  B.L. Njaa  R.J. Panciera  C.N. Pope  M.E. Payton 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2013,27(5):1179-1184

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The Influencing Factor of In Vitro Fertilization and Embryonic Transfer in the Domestic Fowl (Gallus domesticus)     

BC Li  W Li  H Chen  YN Zhang  ZT Zhang  XY Wang  B Gao  TC Dou  KH Wang 《Reproduction in domestic animals》2013,48(3):368-372

This study was conducted to explore the influencing factors of ova in vitro fertilization (IVF) and transfer of the fertilized ova into the oviduct of recipient hens. The efficiency of fertilization was compared using three aspects: (i) the different time of ova collection and transfer, (ii) egg‐laying period of recipient hen; and (iii) semen volume. The following results are observed: 72%, 40% and 0% of ova were found in ovarian sac in 30～40 min, 50～60 min and more than 90 min post‐oviposition, respectively; 20%, 18%, 14% and 5.8% of ova were fertilized with 0.1, 0.2, 0.5 and 1.0 ml semen, respectively; and 33% and 100% of healthy chickens were hatched from fertile ova with 0.1 and 0.5 ml of semen, respectively. All oocytes obtained from ovary and mid‐oviduct were unfertilized. Embryos were transferred into recipient hens 30 min ± 10 min post‐oviposition, and 70% of shelled eggs were produced. There were no eggs produced in the other transfer times. This demonstrated that live chicken can be obtained by IVF of ova collected shortly after oviposition. It was important that the ovum was transferred into the oviduct infundibulum of recipient hens immediately or shortly after oviposition.  相似文献   

Biology of equine piroplasmosis   总被引：11，自引：0，他引：11  

A A Holbrook 《Journal of the American Veterinary Medical Association》1969,155(2):453-454

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Equine piroplasmosis: complement-fixation titers of horses infected with Babesia caballi   总被引：4，自引：0，他引：4  

W M Frerichs  A A Holbrook  A J Johnson 《American journal of veterinary research》1969,30(5):697-702

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