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1.
Developments in plant tissue culture, plant transformation and regeneration, and improvements in techniques to isolate and manipulate viral genes have led to the exploitation of the concept of cross protection: turning the virus onto itself and controlling it with its own genes. By introducing and expressing genes of viral origin in crop plants, scientists have engineered resistance to several plant viruses. Some of the approaches, used singly or in combination, include expression of viral-coat protein, untranslatable sense or antisense RNA, satellite RNA, virusspecific neutralizing antibody genes, plant viral replicase, protease or movement proteins and defective, interfering RNA. All of these approaches have resulted in manifestation of virus resistance to varying degrees in several commercially important crop plants. This review summarizes the recent advances in engineering virus resistance using the above approaches, and lists specific examples of their use in cultivated crop plants of economic importance.H.R. Pappu and C.L. Niblett are with the Plant Pathology Department, University of Florida. Gainesville, FL 32611-0680, USA; R.F. Lee is with the Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA. Florida Agricultural Experiment Station Journal Series No. R-04558.  相似文献   

2.
Rough lemon seedlings were root dip-inoculated in Fries liquid cultures of two Fusarium solani isolates, one from California and one from Florida. Plants were potted and placed in soil temperature tanks at 15, 21, 27, and 33 C. Plant height, trunk diameter, and fresh weight of inoculated plants significantly differed from the control at 15 and 21 C. Plant height was the only growth parameter significantly affected by inoculation at 27 and 33 C. Height of plants inoculated with the California isolate was significantly less than the control at 27 but not at 33 C. Height of plants inoculated with the Florida isolate did not differ from the controls at 27 and 33 C. Significantly more root rot occurred on inoculated plants at 15 and 21 C, but not at 27 and 33 C. Formerly at the University of Florida, IFAS, Agricultural Research and Education Center, P.O. Box 1088, Lake Alfred, FL 33850, USA  相似文献   

3.
Fifty-five sweetpotato cultivars, experimental breeding clones, and plant introduction (PI) accessions were evaluated in 17 field experiments at the USDA, ARS, U.S. Vegetable Laboratory (Charleston, SC; 12 evaluations, 1997-2010), the Clemson University, Edisto Research and Education Center (Blackville, SC; two evaluations, 1998-1999), and the University of Florida, Tropical Research and Education Center (Homestead, FL; three evaluations, 2005-2007). These experiments included two insect-susceptible control entries ('Beauregard' and 'SC1149-19') and three insect-resistant control cultivars ('Regal,' 'Ruddy,' and 'Sumor'). At each location, genotypes differed significantly in the percentage of uninjured roots WDS (wireworm, Diabrotica, Systena) index, the percentage of roots damaged by the sweetpotato weevil (Cylas formicarius (F.)), the percentage of roots damaged by the sweetpotato flea beetle (Chaetocnema confinis Crotch), and the percentage of roots damaged by white grub larvae (including Plectris aliena Chapin and Phyllophaga spp.). 'SC1149-19' had a significantly lower percentage of uninjured roots, a significantly higher WDS index rating, and significantly higher percentages of infestation by flea beetles, grubs, and sweetpotato weevils than most other sweetpotato genotypes in this study. In addition, 43 of 55 genotypes had significantly less overall insect damage than 'Beauregard,' one of the leading commercial orange-fleshed cultivars in the United States. Ten genotypes had significantly less insect injury than 'Picadito,' a commercial boniato-type sweetpotato grown extensively in southern Florida. Many of these sweetpotato genotypes have high levels of resistance to soil insect pests, and they may be useful as sources of insect resistance for use in sweetpotato breeding programs.  相似文献   

4.
Summary The stability-variance statistic, s i 2 , measures the contribution of the ith genotype to genotype x environment interaction. In addition to the knowledge of cultivar stability for an agronomic trait, information on whether stability of one trait can be used to predict stability of another should be useful to breeders. Three separate groups of data, respectively involving CP 79 series, CP 80 series, and CP 81 series experimental clones of sugarcane (Saccharum spp.) were used in this study. Rank-correlation coefficients (rs) between ranks of genotypes for s i 2 's for paired traits indicated in both plant-cane and ratoon crops that stability of tons per hectare of sugar can be predicted from the stability of tons per hectare of cane (THC) and also, to a lesser extent, from the stability of stalk number. The stability of THC also can be reasonably well predicted from the stability of stalk number. Brix stability may give some indication of the stabilities for percentage sucrose and sugar concentration (SC). The s i 2 's for percentage sucrose and SC were almost identical in the CP 79 and CP 81 series (rs varied from 0.93, P<0.01, in plant-cane crop for CP 79 series to 0.98, P<0.01, in plant-cane crop for CP 81 series). Whether correlations were based on s i 2 's estimated across locations within crops or across crops, the magnitude of rs was about the same. Means of various traits were not correlated with their respective s i 2 's (for CP 81 series), indicating that identification and selection of high-yielding sugarcane genotypes with a relatively high degree of stability of performance across test environments should be possible.Cooperative investigation of the Univ. of Florida, Everglades Research and Education Center, Belle Glade, FL, USA; Louisiana Agricultural Experiment Station, LSU Agricultural Center, Baton Rouge, LA, USA; and Sugarcane Field Station, Canal Point, FL, USA. The field work reported in this study was done when the senior author was affiliated with the University of Florida. Florida Agric. Exp. Stns. Journal Series No. 5933  相似文献   

5.
Data from five field experiments using labelled nitrogen fertilizer were used to determine the relative effects of soil nitrogen and fertilizer nitrogen on rice yield. Yield of grain was closely correlated with total aboveground nitrogen uptake (soil+fertilizer), less closely correlated with soil nitrogen uptake and not significantly correlated with fertilizer nitrogen uptake. When yield increase rather than yield was correlated with fertilizer nitrogen uptake, the correlation coefficient was statistically significant.Contribution from the Laboratory for Flooded Soils and Sediments, Agronomy Dept., Louisiana Agri. Exper. Sta., Louisiana State Univ., Baton Rouge, LA 70803, and Univ. of Florida, Agricultural Research and Education Center, Sanford, FL 32771.  相似文献   

6.
Summary Somatic embryos of orchardgrass became quiesent when desiccated to 13% water. Twelve percent germinated after 21 d of desiccated storage at 23° C and 4% developed into green plants. During desiccation, embryos decreased in size, became yellowish and brittle, and their outer walls collapsed. Within 15 min after imbibition, they rapidly enlarged and were indistinguishalbe from nondesiccated embryos. These results suggest that somatic embryos may be engineered to function as synthetic seeds for mass propagation. This research represents a collaborative effort between the Agricultural Experiment Stations of the University of Florida and the University of Tennessee. Research was supported in part by the Competitive Research Grants Office of the U.S. Department of Agriculture, grant 82-CRCR-1-1086, awarded to the University of Tennessee. Florida Agricultural Experiment Station Journal Series No. 7173.  相似文献   

7.
8.
Ryohei Terauchi is a Professor at Kyoto University and a Group Leader at the Iwate Biotechnology Research Center, Japan, studying the evolution of crops and their pathogens. In this interview, Ryohei describes his research interests, how the revolution in sequencing technology helped improve our understanding of orphan crops, and who are the scientists that inspire him.  相似文献   

9.
Dimensions of Native America: The Contact Zone. Museum of Fine Arts, Florida State University, Tallahassee, FL, February 13-March 31. 1998; Appleton Museum of Art, Ocala, FL, April 14-May 31,1998.
Dimensions of Native America: The Contact Zone. Jehanne Teilhet-Fisk and Robin Franklin Nigh. co-curators. Tallahassee: Museum of Fine Arts, Florida State University, 1998. 144 pp.  相似文献   

10.
《Molecular neurobiology》2005,31(1-3):1-300
This special issue of Molecular Neurobiology presents a series of mini-reviews resulting from an ISN satellite symposium entitled Oxidative Mechanisms in Neurodegenerative Disorders Held at the Guilin Park Hotel, Guilin, China on February 7-11, 2004. The timely topics in this symposium were contributed by more than 20 internationally acclaimed scientists and attended by more than 100 participants interested in this subject matter. This satellite symposium was also part of the 6th Biennial Asian-Pacific Society for Neurochemistry (APSN) meeting held in Hong Kong, China. Organizers included Dr. Piu Chan (Capital University of Medical Sciences and Beijing Institute of Geriatrics) Dr. Albert Y. Sun and Dr. Grace Y. Sun (University of Missouri, Columbia, MO). The satellite meeting was hosted by Xuanwu Hospital of Capital University of Medical Sciences and Guilin Medical College, and was generously supported by the following: the International Society of Neurochemistry (ISN), National Institutes of Health (USA) (1 R13 NS047414), the Geriatric Research, Education and Clinical Center (GRECC) VA Medical Center, Minneapolis, MN, USA, The Chinese Society of Neuroscience, Chinese Medical Association, Chinese Journal of Neurology, Shanghai Roche Pharmaceuticals Ltd., and Beijing QuiXave United Technology Ltd. Corporation.  相似文献   

11.
Summary The present experiment compared the establishment of a position habit and three subsequent response shifts with and without discriminative stimuli. The discriminative stimuli employed were (a) 90° and 180° polarization patterns and (b) high and low intensity levels. A significant difference (0.05) was found between the running time performance of the polarization discrimination group and the uniform illumination and bright-dark discrimination groups. No similar difference was found with errors as the dependent measure, and no significant between group differences were found during the response shifts. The conclusion was drawn that the extra-ocular hypothesis could not account for the significant difference.This paper is taken from a Master's Thesis submitted to the Florida State University by the senior author, under the direction of the junior author, in partial fulfillment of the requirements for the degree of Master of Science. A portion of this paper was presented at the 1965 meeting of the American Psychological Association.This research was partially supported by a grant from the Florida State University Research Council. The statistical analyses were made possible in part by a National Science Foundation grant (# GP 671) to the Florida State University Computation Center. The authors are indebted to Dr. F. J. King, Institute of Human Learning, Florida State University, for his contribution to the data analysis.  相似文献   

12.
周艳辉  刘朴  李玉 《菌物研究》2019,17(1):57-62
文中综述了从网柄细胞状黏菌中分离得到的DIF-1及其衍生物、氯代苯并呋喃、三联苯化合物等芳香族化合物,脂肪酸和磷酸化合物、酶以及糖类等,并介绍了各成分的药理或生理作用等。表明网柄细胞状黏菌可以成为某些活性成分及药物的新来源。  相似文献   

13.
5-羟色胺(5-HT)和多巴胺(DA)是两种神经递质,可与众多不同类型的受体结合发挥多种重要的生理功能.现已证明其广泛分布于多种动物的不同组织中,在动物的打斗行为活动中起着重要的调节作用.目前,在虾蟹中已被报道的5-HT受体主要有5种,分别是5-HT1A、5-HT1B、5HT2A、5HT2B和5-HT7;DA受体主要为DA1A、DA1B、DA2和DA4.5-HT和DA及其受体分布存在明显的种属和组织特异性.5-HT和DA参于了虾蟹打斗行为的调节过程并有不同的调节机理.5-HT可以调节环磷酸腺苷(cAMP)或高血糖激素(CHH)的释放,促进或抑制虾蟹打斗行为;而DA同样能够通过调节cAMP及COMT等物质的释放来调节虾蟹打斗行为.  相似文献   

14.
木屑一直是灰树花主要的栽培基质,但木质资源日趋匮乏。本文采用单纯格子法筛选替代木屑基质的原材料及高产配方,以玉米芯、玉米秸秆、大豆秸秆、水稻秸秆为栽培基质,以产量为考核指标,建立各组分配比与产量之间的回归模型,优化栽培配方及考察配方中各组分的互作效应。结果表明:玉米芯可以替代木屑栽培灰树花,大豆秸秆、水稻秸秆和玉米秸秆可以与玉米芯进行合适配比,也可以替代木屑基质。优化的高产配方为75%玉米芯,23%麦麸,2%轻质碳酸钙,每袋产量平均达133.3 g,比对照配方平均产量(97.25 g)高出36.05 g,提高了37.07%。  相似文献   

15.
This address outlines important steps for ensuring the future of biofeedback and applied psychophysiology. These steps are contained in the acronym PHUTRE, wherein PH stands for Political activism of the Hard and fast variety, U represents United front, T encompasses Transfer of knowledge (from clinician to researcher, researcher to clinician, and from both to students in training), R refers to our Research base, and E represents the Excitement that our field has the potential to generate.This paper is based on the Presidential Address delivered at the annual meeting of AAPB, Atlanta, Georgia, March, 1994. Please address correspondence to Frank Andrasik, Ph.D., Center for Behavioral Medicine, The University of West Florida, 11000 University Parkway, Pensacola, Florida 32514.  相似文献   

16.
Summary We describe a tissue culture procedure for somatic embryogenesis and plantlet regeneration in cotton (Gossypium hirsutum L. cv. Coker 312). Callused explants or individual globular embryos were transferred to basal media to induce somatic embryogenesis. To determine characteristic early indicators of successful germination and conversion, we identified six types of embryos that developed on basal media. Two of the six embryo types, designated as tulip-shaped and trumpet-shaped, could undergo conversion in preliminary tests, whereas the others had little or no developmental potential. Several media treatments designed to enhance the maturation of globular somatic embryos failed to increase the fraction of embryos which matured to form recoverable types. In efforts to improve plantlet recovery, tulip-shaped embryos were used in limited trials to contrast the effects of chemical and physical desiccation treatments on germination and conversion. The selective use of tulip-shaped somatic embryos, coupled with partial desiccation, seems to have augmented plant recovery. Growth habit, flowering, seed set, and lint production of most of the regenerated plants were comparable to seed-derived plants grown under the same conditions. Partial research support was provided by state and federal funds appropriated to the Ohio Agricultural Research and Development Center, The Ohio State University.  相似文献   

17.
18.
The effect of a seed source on primary succession in a forest ecosystem   总被引:2,自引:0,他引:2  
An analysis of the Relative Importance Value Index (RIVI) of later successional tree species and the Shannon diversity indexH of all tree and shrub species was undertaken on previously mined sites within a sparsely forested area in central Florida, USA. A comparative analysis of the distance to a seed source and the age of a site suggested that the distance to a seed source was the best predictor (R 2=0.85) of the regeneration of the later successional species and a good predictor of species diversity. Both theRIVI of the later successional species and the diversity index decreased with the distance from the seed source. The lack of a seed source containing climax species resulted in arrested succession at some sites. It is suggested that biological information is the causative means of succession and the dispersal of this information entails spatial dependency while its introduction and development are time dependent processes.Research was part of a project of the Center for Wetlands, University of Florida, Gainesville under contract with the Florida Institute of Phosphate Research. Interactions of Wetlands with Phosphate Mining, H. T. Odum and G. R. Best, principal investigators. B. T. Rushton, J. Butner, G. R. Best, R. S. Schnoes and S. R. Humphrey are thanked for the use of their data.  相似文献   

19.
Summary On September 14 through 16, 1988, a meeting on the use of human fetal tissue in transplantation was held at the National Institutes of Health, Bethesda Maryland, USA. The meeting sponsored by NIH for the Human Fetal Tissue Transplantation Research Panel, a consultant group to the Advisory Committee to the Director. The consultant group was convened to deal with the scientific, judicial and moral questions associated with research involving transplantation of human fetal tissue obtained after induced abortions. The first day of the meeting was devoted to presentations addressing scientific issues. Included among the speakers was Dr. Lars Olson, Professor of Neurobiology, Karolinska Institute, Stockholm, who described the use of transplanted human fetal tissue in the treatment of patients with Parkinkson's disease and Dr. Eugene Redmond, Professor of Psychiatry, Yale University School of Medicine, who showed results of work with transplantation of tissue to correct induced Parkinson-like disease in monkeys. Other speakers addressed the present, past or potential use of fetal tissue in the treatment of diabetes, immune disorders, and other diseases, as well as the use of fetal cells in the production of biologicals. At the conclusion of the meeting the panel did not recommend that research be halted on fetal tissue within the context discussed, although the recommendation of the committee is not binding, and an additional assembly of the panel will probably occur before the final recommendation to an NIH advisory committee is made in November. Other meetings on this subject include a meeting on the use of fetal tissue sponsored by the American Association of Tissue Banks, March 6–7, 1989, in Washington D. C. (Crystal City) and a meeting June 10, 1989, the day before the annual meeting of the Tissue Culture Association, USA, in Orlando, Florida, on fetal cells and ownership of cultured cells and products derived from clinical specimens. Following are statements to the Human Fetal Tissue Transplantation Research Panel presented September 14, 1988, by Dr. David Barnes, Associate Professor of Biochemistry and Biophysics in the Environmental Health Sciences Center at Oregon State University, USA, who was asked to address for the panel recent advances in cell culture related to fetal tissue, and Dr. Robert E. Stevenson, Director of the American Type Culture Collection, President of the Tissue Culture Association, USA, and Chairman of the Committee on Cells and Tumors of the American Association of Tissue Banks.  相似文献   

20.
Summary The vertical distribution of inorganic nutrient concentrations in red pine were dependent on the foliage age. Older foliage did not show an average vertical gradient while younger foliage did show a significant gradient. Horizontal gradients across foliage age classes in a branch whorl were consistent for all branch whorls, but the relative difference between the concentration of the current foliage and foliage three years-old or older was dependent on crown position. Coefficients of variation (CV) did not show a variability gradient in the crown for nitrogen and phosphorus. Variability of potassium tended to decrease as foliage age increased. Contribution of the University of Florida, Soil Science Department, Gainesville, FL and State University of New York, College of Environmental Science and Forestry, Syracuse, New York. Florida Agricultural Experiment Station Journal Series No. 3017.  相似文献   

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