Although backcrossing methods are simplified when the characteristic being transferred is a dominant allele, a recessive allele may also be transferred. In this instance it may be necessary to introduce a test of the progeny to determine if the desired characteristic has been successfully transferred. Many traits have been identified that are not regularly selected for in the development of a new variety but that can be improved by backcrossing techniques. A genetic locus conferring the traits may or may not be transgenic.
Examples of such traits known to those of skill in the art include, but are not limited to, male sterility, waxy starch, herbicide resistance, resistance for bacterial, fungal, or viral disease, insect resistance, male fertility and enhanced nutritional quality.
These genes are generally inherited through the nucleus, but may be inherited through the cytoplasm. Some known exceptions to this are genes for male sterility, some of which are inherited cytoplasmically, but still act as a single locus trait. Direct selection may be applied where a genetic locus acts as a dominant trait. An example of a dominant trait is the herbicide resistance trait. For this selection process, the progeny of the initial cross are sprayed with the herbicide prior to the backcrossing.
The spraying eliminates any plants which do not have the desired herbicide resistance characteristic, and only those plants which have the herbicide resistance gene are used in the subsequent backcross. This process is then repeated for all additional backcross generations. Many useful traits are those which are introduced by genetic transformation techniques.
Methods for the genetic transformation of corn are known to those of skill in the art. For example, methods which have been described for the genetic transformation of corn include electroporation U.
It is understood to those of skill in the art that a transgene need not be directly transformed into a plant, as techniques for the production of stably transformed corn plants that pass single loci to progeny by Mendelian inheritance are well known in the art. Such loci may therefore be passed from parent plant to progeny plants by standard plant breeding techniques that are well known in the art. Non-limiting examples of traits that may be introduced into a corn plant according to specific embodiments of the invention are provided below.
Examples of genes conferring male sterility include those disclosed in U. The use of herbicide-inducible male sterility genes is described in U. Male sterility genes can increase the efficiency with which hybrids are made, in that they eliminate the need to physically emasculate the corn plant used as a female in a given cross.
Where one desires to employ male-sterility systems with a corn plant in accordance with the invention, it may be beneficial to also utilize one or more male-fertility restorer genes. The CMS line is propagated by pollination with the maintainer line, with all of the progeny being male sterile, as the CMS cytoplasm is derived from the female parent.
These male sterile plants can then be efficiently employed as the female parent in hybrid crosses with the restorer line, without the need for physical emasculation of the male reproductive parts of the female parent. The presence of a male-fertility restorer gene results in the production of fully fertile F 1 hybrid progeny.
If no restorer gene is present in the male parent, male-sterile hybrids are obtained. Such hybrids are useful where the vegetative tissue of the corn plant is utilized, e. Therefore, one aspect of the current invention concerns plants of the corn variety CV comprising a genetic locus capable of restoring male fertility in an otherwise male-sterile plant.
Examples of male-sterility genes and corresponding restorers which could be employed with the plants of the invention are well known to those of skill in the art of plant breeding and are disclosed in, for instance, U.
Numerous herbicide resistance genes are known and may be employed with the invention. An example is a gene conferring resistance to a herbicide that inhibits the growing point or meristem, such as an imidazalinone or a sulfonylurea. Biology, , ; and Miki et al. Resistance genes for glyphosate resistance conferred by mutant 5-enolpyruvl-3 phosphikimate synthase EPSPS and aroA genes, respectively , and hygromycin B phosphotransferase, and to other phosphono compounds such as glufosinate phosphinothricin acetyl transferase PAT and Streptomyces hygroscopicus phosphinothricin-acetyl transferase bar genes may also be used.
See, for example, U. A hygromycin B phosphotransferase gene from E. European patent application No. The nucleotide sequence of a phosphinothricin-acetyltransferase gene is provided in European patent application No. DeGreef et al. Biotechnology, , , describe the production of transgenic plants that express chimeric bar genes coding for phosphinothricin acetyl transferase activity.
Exemplary genes conferring resistance to phenoxy propionic acids and cycloshexones, such as sethoxydim and haloxyfop, are the Acct-S1, Accl-S2 and Acct-S3 genes described by Marshall et al. Przibila et al. Plant Cell, , , describe the transformation of Chlamydomonas with plasmids encoding mutant psbA genes.
Nucleotide sequences for nitrilase genes are disclosed in U. The herbicide methyl viologen inhibits CO 2 assimilation. Foyer et al. Plant Physiol. Siminszky Phytochemistry Reviews, , describes plant cytochrome Pmediated detoxification of multiple, chemically unrelated classes of herbicides.
Other examples of herbicide resistance have been described, for instance, in U. The waxy characteristic is an example of a recessive trait. In this example, the progeny resulting from the first backcross generation BC1 must be grown and selfed. A test is then run on the selfed seed from the BC1 plant to determine which BC1 plants carried the recessive gene for the waxy trait.
In other recessive traits additional progeny testing, for example growing additional generations such as the BC1S1, may be required to determine which plants carry the recessive gene. Plant defenses are often activated by specific interaction between the product of a disease resistance gene R in the plant and the product of a corresponding avirulence Avr gene in the pathogen. A plant line can be transformed with cloned resistance gene to engineer plants that are resistant to specific pathogen strains.
See, for example, Jones et al. Science, , cloning of the tomato Cf-9 gene for resistance to Cladosporium fulvum ; Martin et al. Science, , tomato Pto gene for resistance to Pseudomonas syringae pv. A viral-invasive protein or a complex toxin derived therefrom may also be used for viral disease resistance. See Beachy et al. Coat protein-mediated resistance has been conferred upon transformed plants against alfalfa mosaic virus, cucumber mosaic virus, tobacco streak virus, potato virus X, potato virus Y, tobacco etch virus, tobacco rattle virus and tobacco mosaic virus.
A virus-specific antibody may also be used. See, for example, Tavladoraki et al. Nature, , , who show that transgenic plants expressing recombinant antibody genes are protected from virus attack. Virus resistance has also been described in, for example, U. Logemann et al. Biotechnology, , , for example, disclose transgenic plants expressing a barley ribosome-inactivating gene having an increased resistance to fungal disease.
Plant defensins may be used to provide resistance to fungal pathogens Thomma et al. Other examples of fungal disease resistance are provided in U. Nematode resistance has been described, for example, in U. One example of an insect resistance gene includes a Bacillus thuringiensis Bt protein, a derivative thereof or a synthetic polypeptide modeled thereon. See, for example, Geiser et al.
Another example is a lectin. See, for example, Van Damme et al. Plant Molec. A vitamin-binding protein may also be used, such as avidin.
This application teaches the use of avidin and avidin homologues as larvicides against insect pests. Yet another insect resistance gene is an enzyme inhibitor, for example, a protease or proteinase inhibitor or an amylase inhibitor. See, for example, Abe et al. An insect-specific hormone or pheromone may also be used. See, for example, the disclosure by Hammock et al. Nature, , , of baculovirus expression of cloned juvenile hormone esterase, an inactivator of juvenile hormone; Gade and Goldsworthy Eds.
The diuretic hormone receptor DHR was identified in Price et al. Insect Mol. Still other examples include an insect-specific antibody or an immunotoxin derived therefrom and a developmental-arrestive protein. See Taylor et al. Seventh Inn Symposium on Molecular Plant-Microbe Interactions, Edinburgh, Scotland, Abstract W97, , who described enzymatic inactivation in transgenic tobacco via production of single-chain antibody fragments. Numerous other examples of insect resistance have been described.
Genes may be used conferring modified fatty acid metabolism, in terms of content and quality. For example, stearyl-ACP desaturase genes may be used. See Knutzon et al. USA, , EP Modified oils production is disclosed, for example, in U. High oil production is disclosed, for example, in U. Modified fatty acid content is disclosed, for example, in U. Phytate metabolism may also be modified by introduction of a phytase-encoding gene to enhance breakdown of phytate, adding more free phosphate to the transformed plant.
For example, see Van Hartingsveldt et al. In corn, this, for example, could be accomplished by cloning and then reintroducing DNA associated with the single allele which is responsible for corn mutants characterized by low levels of phytic acid. See Raboy et al. A number of genes are known that may be used to alter carbohydrate metabolism.
For example, plants may be transformed with a gene coding for an enzyme that alters the branching pattern of starch. See Shiroza et al. The Z10 gene encoding a 10 kD zein storage protein from maize may also be used to alter the quantities of 10 kD zein in the cells relative to other components Kirihara et al.
Patent Appl. Abiotic stress includes dehydration or other osmotic stress, salinity, high or low light intensity, high or low temperatures, submergence, exposure to heavy metals, and oxidative stress.
Delta-pyrrolinecarboxylate synthetase P5CS from mothbean has been used to provide protection against general osmotic stress. Mannitolphosphate dehydrogenase mt1D from E. Choline oxidase codA from Arthrobactor globiformis can protect against cold and salt. Additional protection from cold can be provided by omegafatty acid desaturase fad7 from Arabidopsis thaliana.
Overexpression of superoxide dismutase can be used to protect against superoxides, as described in U. Additional traits can be introduced into the corn variety of the present invention.
Another trait that may find use with the corn variety of the invention is a sequence which allows for site-specific recombination. The recombinase genes can be encoded at any location within the genome of the corn plant, and are active in the hemizygous state. It may also be desirable to make corn plants more tolerant to or more easily transformed with Agrobacterium tumefaciens.
Expression of p53 and iap, two baculovirus cell-death suppressor genes, inhibited tissue necrosis and DNA cleavage. Reviews, , In addition to the modification of oil, fatty acid or phytate content described above, it may additionally be beneficial to modify the amounts or levels of other compounds.
For example, the amount or composition of antioxidants can be altered. Additionally, seed amino acid content may be manipulated. International Patent Appl. As described above, techniques for the production of corn plants with added traits are well known in the art see, e. A non-limiting example of such a procedure one of skill in the art would use for preparation of a corn plant of CV comprising an added trait is as follows: a crossing corn plant CV to a second nonrecurrent corn plant comprising a locus to be converted in corn plant CV; b selecting at least a first progeny plant resulting from the crossing and comprising the locus; c crossing the selected progeny to corn plant CV; and d repeating steps b and c until a plant of variety CV is obtained comprising the locus.
Following these steps, essentially any locus may be introduced into corn variety CV For example, molecular techniques allow introduction of any given locus, without the need for phenotypic screening of progeny during the backcrossing steps. The techniques are carried out as follows: Seeds of progeny plants are grown and DNA isolated from leaf tissue see Sambrook et al. Approximately one gram of leaf tissue is lyophilized overnight in 15 ml polypropylene tubes.
Freeze-dried tissue is ground to a powder in the tube using a glass rod. Powdered tissue is mixed thoroughly with 3 ml extraction buffer 7. Connect me to people I follow on Twitter? If we find matches from the people you follow on Twitter, we'll connect you to them right away.
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Connecting to your webcam. We found at least four and possibly five different sugary1 alleles, indicating five different independent origins of sugary sweet corn.
We carried out a morphological study. While results are not yet conclusive, certain accessions of Pointed Pops have a tendency to develop the lower floret, the diagnostic characteristic of Country Gentleman.
Rust reaction and plant development: In previous reports to this committee I have discussed our work on recurrent selection for altered development and the possible effects of developmental changes on reaction to common rust. In data collected over two years we observed a strong relationship between timing of developmental phase change and resistance to rust.
This relationship is strongest in lower leaves and diminishes acropetally. Recurrent selection for endosperm and color markers: Divergent recurrent selection for endosperm phenotype in su1 populations results in change in a number of correlated traits.
The proportion of red cobs in the population is strongly correlated to increased pseudostarchiness. In the other direction towards extreme sugary the number of plants that produce purple kernels in testcrosses with a1 increased over cycles. Color genes in sh2 hybrids: We tested for the presence of A1 in 11 commercial sh2 hybrids; A1 was present segregating in one hybrid.
Germplasm recovery: We increased seed of six open-pollinated cultivars from the pre-hybrid era and placed the donated seed in the National Plant Germplasm System. Breeding program: We continue inbred and hybrid development programs, numerous recurrent selection programs and screening temperate sweet x tropical populations for resistance to northern leaf blight, common rust, and MDMV.
Impacts The work in this report can be divided into two broad categories, product quality and disease resistance. Understanding the genetics underlying sweet corn quality allows us to develop better tasting, more nutritious cultivars benefiting consumers and in turn farmers and processors.
Knowledge of disease resistance mechanisms and development of sweet corn cultivars with better resistance will allow farmers to produce better sweet corn with reduced environmental impacts. Publications Dickert, T. E, and W. Heterosis for maturity among early sweet corn. Response to selection for the timing of vegetative phase transition in a maize population.
Crop Sci. Hort Sci. Hurkman, M. Hurkman, C. Basso, and B. Altered timing of vegetative phase change and response to Puccinia sorghi. Basso C. Hurkman, and W. Agronomy Abst. CtracyPoster Tracy, W. AtracyPoster Am. Madison, WI Tracy, W. Midwest Food Proc. Processing Crops Manual and Proceedings Divergent selection for vegetative phase change was successful with last leaf with juvenile wax exhibiting a strong linear response to The average last leaf with juvenile wax in C0 was 9.
Average number for C3 late was We then initiated a planting dating date study in which all seven cycles were planted at three dates. They then were inoculated on the same day with one planting at the v5 stage, another at v10 and the third at v For the v5 group there were significant differences among cycles but they did not indicate any linear trends and the level of rust was high in all cycles.
Inoculation at v10 resulted in a significant linear trend over cycles. In the case of v15 there was a significant linear trend for the late direction with the late plants having more rust than C0. We also studied the genes involved in anthocyanin synthesis in populations selected for endosperm type and found it was due to p.
We have been screening temperate sweet x tropical populations for resistance to northern leaf blight, common rust, and MDMV. We are releasing 5 new sh2 inbreds. Impacts Examining the relationship between plant development and disease resistance will increase our understanding of certain forms of quantitative or adult plant resistance and may lead to improved cultivars or management strategies. The breeding work involved with the development of unique germplasm will lay the foundation for efforts such as the phase change work.
Release of new inbred stocks should be directly useful to sweet corn breeders. Publications Tadmor, Y. Tracy, G. Yousef, J. Juvik, V. This repository is part of the Iowa Research Commons. Privacy Copyright. Skip to main content. Title Estimation of genetic variability in two maize populations.
Authors L. Publication Version Published Version. Within the work itself the author names none of those closest to him, in truth less than three names are used throughout the whole work. He also declines to mention which unit or division he was part of, or give any background about himself to how he came to be where he is.
Finally the work itself reads more like a script drawn from a Hollywood action movie, in truth I feel it would make an exciting one, but is unbelievable in its content in many places, mostly the battles, especially when held up against other primary sources. Though I will leave it to the reader to come to their own conclusions I shall be treating this work as a fictional memoir or novel which I believe it truly is.
The main story itself takes place over a period of five days, with subsequent sections much later, and is told entirely from the perspective of the "author" Wolfgang Faust.
The presentation of the horror engulfing the now destroyed German state is thrillingly presented. The constant fear of attack by the Russians, the terrified, tired and worn out soldiers, many too exhausted to bother fighting any longer, and the vast hordes of civilian refugees whose only instinct now is survival.
The battles described on their flight westward are grim, as the Russian Army launches constant and relentless counter-attacks and artillery bombardments against the long column as it trundles forward. However it is not just the Russians who are to be feared. Among the ranks of the German forces are groups of SS soldiers and field police trying to keep order among the ranks but killing those who refuse to fight or show defeatist attitudes. There are former German soldiers, long since captured by the Russians, but who now flight along side them, sneaking into the German lines causing havoc, and hindering the progress west.
Central to the story are a number of key elements. The first is found in their duty to Germany, to be there and help to rebuild her after the War, something which will not be possible should they be captured by the Russians.
The heroic idea of the soldier is naturally present, of fighting against overwhelming odds and of refusing to give in, at least for now, to the inevitable downfall.
The protagonist is constantly with odds against himself to try and scratch some essence of glory, of heroism from the crumbling world around him, but he is also under no illusion that what is currently befalling them was entirely of their own doing.
Finally there is the Panther tank itself. The idea of the Panther role in the story are far more than just a tool of war. To the protagonist this machine is a second home, a world which only he and his crew truly know, it is a living beast protecting him and the horde of soldiers and civilians following behind.
It is the only real protection they have against the Soviet Army, one which time and again turns out to be their saving grace. In the end the reader too grows attached to this metal monster, and the reality is ever present that without it, the actors of this story will have no chance of survival. Overall "The Last Panther" is a very enjoyable war novel and will be of interest to anyone who has an interest in the final days of world war two. Many people will take issue with this work, commenting on its depiction of the Russians unsympathetic monsters who blast through hordes of civilians and soldiers alike with their tanks and artillery, or on the heroic and defiant depictions of the SS or Wehrmacht.
But it must be remembered that this work is supposed to be a "memoir" of a soldier from the German perspective on the closing days of the war and in this role I feel it does a good job, and gives an authentic feel of tone, provides historically believable emotions and feelings and images of the war, as well as the over the top elements of battles which all too often later filter into folk memory and legend. As such I would recommend this novel as an exciting, fast paced and easy read suited to anyone with an interest in the closing days of world war two.
Oct 21, William Webb rated it it was amazing. There seems to be significant debate about whether this book is fiction or truth. Told in first person, the author gives no details about his own unit or those fighting around him, no names that we can verify his story with, nothing to prove it one way or the other. And yet this doesn't interfere with the enjoyment of reading it. IF the book is fiction, as many think it is, then the author has written a brilliant story that required intimate knowledge of many aspects of operating a Panther.
Mar 10, K. Sivils rated it it was amazing. This autobiographical account of the Halbe Kessel reads like a novel. The author, Wolfgang Faust, commanded a German Panther. A veteran of the Eastern Front, he'd seen more than his share of horror. What he witnessed in the Halbe Kessel made even a hardened veteran take pause. It's a bit strange reading a book about WW II where the Germans are not the bad guys I'm American as the story tells of the frantic attempt at escape by German military personnel and civilians.
Hoping to reach the America This autobiographical account of the Halbe Kessel reads like a novel. Hoping to reach the American line at the River Elbe, Faust and his crew must first fight their way into the Halbe Kessel, cross the enveloped area, and then fight their way out of the trapped pocket to the Americans. Even with the normal rigid discipline of the German military largely gone, those soldiers who want to live put up a fierce fight to escape the cruel fate that awaits them if captured by the Soviets.
Upon stepping back from the drama of the story and considering what was at stake, the story demonstrates the extreme cruelty of the Soviet military. Yes, the German war machine was certainly guilty of war crimes of unimaginable cruelty and were the invaders of the Soviet nation, all of which would certainly create a strong desire for revenge.
None of that explains the slaughter of Russian POWs who were forced into slave labor by the Germans 1. All of whom were put to death and their families sent to Siberia. Their crime - they had been taken prisoner. The region of Germany where the town of Halbe was located had been overrun by Russian forces on their way to Berlin. The German forces trapped in the Kessel were no threat to the Soviet war machine.
The war would be over in days. Rather than being content to keep the trapped German soldiers in the pocket, the Russians suffered considerable casualties as a result of their efforts to slaughter everyone, soldier and civilian, in the pocket.
Faust describes the Soviet fighting style which could basically be described as human wave tactics. Faust and his crew were limited in their ability to kill only by the limited amount of ammunition available to them. Russian T tanks went into battle carrying infantry, infantry who died the instant a round from Faust's Panther hit the T in one instance.
It was common for the tank riders to dismount once the T's engaged Faust and his crew only to be run over and crushed by their own tanks.
It was a bit strange, but interesting, to read the translated version which retained the German military's slang for its own weapons, formations and the enemy.
Faust wrote down his experiences within his year of captivity as an American POW but waited decades to publish his memoir. For those interested in historical accounts written by participants instead of professional historians, this is a great read.
Aug 04, Guy rated it really liked it Shelves: ww2. The book is not well crafted, but the author was not a writer but a tank commander in the 21st Panzer Division of the German Wehrmacht in May Consequently the style is unsophisticated and virtually a continuous, straightforward narrative.
Perhaps this is best, because what Wolfgang Faust describes is simply Hell on Earth. This is warfare at it's most savage where more civilians were being slaughtered than soldiers. The Soviets were exacting a bloody, terrifying revenge upon the fallen Reich The book is not well crafted, but the author was not a writer but a tank commander in the 21st Panzer Division of the German Wehrmacht in May The Soviets were exacting a bloody, terrifying revenge upon the fallen Reich and the situation was simple -kill or be killed with the civilians joining in the fight for survival.
In places it was reminiscent of Anthony Beevor's 'Berlin' as it details atrocity after atrocity and had Beevor written it, it would have been as sensational a piece. So do not read this for its literary construction, but as a piece on the raw horror of war.
However, I suspect this book to be a piece of total fiction. There is little geographic detail and even less unit detail. What this man sees from the driver's viewing slot of a Panzer V is beyond reasonable belief. The Eastern Front was hell on earth for all sides, but I simply cannot believe what is written here as fact.Lukas Hallauer is on Facebook. Join Facebook to connect with Lukas Hallauer and others you may know. Wenn sie sich anzieht, sind fünf Minuten in etwa eine halbe Stu, Für alle die nicht rechnen können: + = Also haben wir noch um die ob wir ‚ne, Die dümmsten Zitate aus Briefen an Versicherungen.