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Comparative Structural Study Of Leaf Spot Disease Of Safflower And Sugar Beet By Cercospora Beticola, Robert T. Lartey, Andrew W. Lenssen, Robert G. Evans, Soumitra Ghoshroy Jan 2007

Comparative Structural Study Of Leaf Spot Disease Of Safflower And Sugar Beet By Cercospora Beticola, Robert T. Lartey, Andrew W. Lenssen, Robert G. Evans, Soumitra Ghoshroy

Andrew W. Lenssen

Sugar beet and safflower are sometimes rotated or grown side by side in the Sidney, MT region of the Lower Yellowstone River Basin (LYRB). Cercospora beticola and C. carthami infect sugar beet (Beta vulgaris) and safflower (Carthamus tinctorius) respectively. C. beticola is ubiquitous in sugar beet, but C. carthami has not been reported in LYRB. Observations of unusual leaf spots on safflower in Sidney led to investigation and subsequent identification of safflower as a host of C. beticola. We describe a comparative structural study of progression of C. beticola infection and disease development in both sugar beet and safflower. The …


Incorporating Sheep Into Dryland Grain Production Systems I. Impact On Over-Wintering Larva Populations Of Wheat Stem Sawfly, Cephus Cinctus Norton (Hymenoptera: Cephidae), P. G. Hatfield, Sue L. Blodgett, T. M. Spezzano, H. B. Goosey, Andrew W. Lenssen, R. W. Kott, C. B. Marlow Jan 2007

Incorporating Sheep Into Dryland Grain Production Systems I. Impact On Over-Wintering Larva Populations Of Wheat Stem Sawfly, Cephus Cinctus Norton (Hymenoptera: Cephidae), P. G. Hatfield, Sue L. Blodgett, T. M. Spezzano, H. B. Goosey, Andrew W. Lenssen, R. W. Kott, C. B. Marlow

Andrew W. Lenssen

Wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae) is the most damaging insect pest to Montana’s $1 billion dollar per year grain industry. Current WSS control methods are either expensive, reduce wheat yields, or are not effective. Our objective was to compare burning, grazing, tilling, trampling and clipping wheat stubble fields on over-wintering WSS larval populations. Treatments were evaluated in three experiments using a randomized complete block design and four replications at each site. Eight, six, and two sites were used for Experiments 1, 2, and 3, respectively. Contrast statements were used to make pre-planned comparisons among treatments. For …


Cropping Sequence And Tillage System Influences Annual Crop Production And Water Use In Semiarid Montana, Usa, Andrew W. Lenssen, G. D. Johnson, G. R. Carlson May 2006

Cropping Sequence And Tillage System Influences Annual Crop Production And Water Use In Semiarid Montana, Usa, Andrew W. Lenssen, G. D. Johnson, G. R. Carlson

Andrew W. Lenssen

Available water is typically the biggest constraint to spring wheat production in the northern Great Plains of the USA. The most common rotation for spring wheat is with summer fallow, which is used to accrue additional soil moisture. Tillage during fallow periods controls weeds, which otherwise would use substantial amounts of water, decreasing the efficiency of fallow. Chemical fallow and zero tillage systems improve soil water conservation, allowing for increased cropping intensity. We conducted a field trial from 1998 through 2003 comparing productivity and water use of crops in nine rotations under two tillage systems, conventional and no-till. All rotations …


Effects Of Elevated Co2 And Defoliation On Grasses: A Comparative Ecosystem Approach, Brian J. Wilsey, James S. Coleman, Samuel J. Mcnaughton Jan 1997

Effects Of Elevated Co2 And Defoliation On Grasses: A Comparative Ecosystem Approach, Brian J. Wilsey, James S. Coleman, Samuel J. Mcnaughton

Brian J. Wilsey

Three plant species from each of three grassland ecosystems were grown under elevated (700 mL/m3) and ambient (350 mL/m3) CO2 and were defoliated or left undefoliated to test whether species response to elevated CO2 and grazing is related to evolutionary grazing history or to mode of photosynthesis. The three ecosystems represented a tropical grassland dominated by C4 species (the Serengeti of Africa), a temperate grassland dominated by a mixture of C3 and C4 species (Flooding Pampa of South America), and a northern temperate grassland dominated by C3 species (Yellowstone National Park of North America). Plants were grown in growth chambers …


Induced Lsoflavonoids In Diverse Populations Of Astragalus Cicer, Andrew W. Lenssen, Susan S. Martin, Charley E. Townsend Jan 1994

Induced Lsoflavonoids In Diverse Populations Of Astragalus Cicer, Andrew W. Lenssen, Susan S. Martin, Charley E. Townsend

Andrew W. Lenssen

lsoflavonoids were induced in mature leaves of the legume Asbagalus cicer L. by spores of the fungus Bipoaris zeicola. The five major elicited compounds included two isoflavans (mucronulatol and astraciceran), two isoflavones (cajanin and acicerone), and a pterocarpan (maackiain). Only occasional traces of these compounds were detected in controls. Among 41 populations originating in Europe or Russia, mean total elicited isoflavonoid content differed 12-fold. Mucronulatol was the predominant compound elicited, comprising 20-70% of total isoflavonoids. Significant interpopulational differences existed for each isoflavonoid, but no geographic patterns of total or relative proportions of the five compounds were discernible.


Forage Quality Of Genetically Diverse Alfalfa Germplasms At Four Phenological Growth Stages, Andrew W. Lenssen, E. L. Sorensen, G. L. Posler Jan 1990

Forage Quality Of Genetically Diverse Alfalfa Germplasms At Four Phenological Growth Stages, Andrew W. Lenssen, E. L. Sorensen, G. L. Posler

Andrew W. Lenssen

Forage quality of various alfalfa (Medicago sativa L.) cultivars has been determined under different environmental conditions, and numerous trials with alfalfa have documented an inverse relationship between forage quality and maturity. Little information is available, however, regarding the comparative forage quality of the germplasm sources from which most USA cultivars were developed. We compared forage quality of these germplasm sources at four phenological stages under disease- and insect-free conditions in a greenhouse. Germplasm sources (cultivars) tested were: Indian (Sirsa # 9), African (African), Peruvian (Hairy Peruvian), Flemish (DuPuits), Turkistan (Lahontan), Chilean (Kansas Common), M. varia (Grimm), and Ladak (Ladak). Four …


Molecular-Marker-Facilitated Investigations Of Quantitative-Trait Loci In Maize. I. Numbers, Genomic Distribution And Types Of Gene Action, Jonathan F. Wendel, M. D. Edwards, Charles W. Stuber May 1987

Molecular-Marker-Facilitated Investigations Of Quantitative-Trait Loci In Maize. I. Numbers, Genomic Distribution And Types Of Gene Action, Jonathan F. Wendel, M. D. Edwards, Charles W. Stuber

Jonathan F. Wendel

Individual genetic factors which underlie variation in quantitative traits of maize were investigated in each of two F 2 populations by examining the mean trait expressions of genotypic classes at each of 17-20 segregating marker loci. It was demonstrated that the trait expression of marker locus classes could be interpreted in terms of genetic behavior at linked quantitative trait loci (QTLs). For each of 82 traits evaluated, QTLs were detected and located to genomic sites. The numbers of detected factors varied according to trait, with the average trait significantly influenced by almost two-thirds of the marked genomic sites. Most of …


Additional Mapping Of Isozyme Loci: Localization Of Acp4, Dia2, Adkl, Tpi3, And Sadl, Jonathan F. Wendel, Major M. Goodman, Charles W. Stuber Jan 1986

Additional Mapping Of Isozyme Loci: Localization Of Acp4, Dia2, Adkl, Tpi3, And Sadl, Jonathan F. Wendel, Major M. Goodman, Charles W. Stuber

Jonathan F. Wendel

We recently listed the isozyme loci being studied by starch gel electrophoresis in our laboratory and summarized the available mapping data in a series of reports (Wendel et al., MGCNL 59:87-90). Subsequent work has resulted in further clarification of the chromosomal locations of markers on chromosomes 1 (Acp4, Dia2), 6 (Adkl), 8 (Tpi3), and 10 (Sadl). Previously unreported information on these loci and their chromosomal locations follows.


Tpi4 Is Located Near The Centromere On The Long Arm Of Chromosome 3, Jonathan F. Wendel, J. B. Beckett Jan 1986

Tpi4 Is Located Near The Centromere On The Long Arm Of Chromosome 3, Jonathan F. Wendel, J. B. Beckett

Jonathan F. Wendel

Tpi4, one of the three genes encoding cytosolic triose phosphate isomerase isozymes, was earlier shown to be on 3L between Pgd2 (phosphogluconate dehydrogenase) and the centromere (Wendel et al., MNL 59:88). In an effort to better localize Tpi4, a series of crosses was made between Tpi4 testers and stocks carrying three B-A translocations believed to be near the centromere on 3L.


Localization Of Two New Isozyme Loci, Hexl And Tpi4, To Chromosome 3, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman Jan 1985

Localization Of Two New Isozyme Loci, Hexl And Tpi4, To Chromosome 3, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman

Jonathan F. Wendel

Recent work with starch gel electrophoresis of coleoptile extracts has indicated that Hexl, the structural locus for the most anodal set of hexokinase isozymes, and Tpi4, which encodes the slowest migrating set of triose phosphate isomerase bands, are located on chromosome 3.


Mapping Data For 34 Isozyme Loci Currently Being Studied, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman Jan 1985

Mapping Data For 34 Isozyme Loci Currently Being Studied, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman

Jonathan F. Wendel

With the recent localization of several new loci, a composite listing of these loci and chromosomal locations has been compiled and is shown in Table 1. Although locations of some of the loci are tentative, many are very precisely located from studies involving 1600 to more than 1900 F2 plants.


Linkage Relationships Between A New Locus, Hex2, And Previously Assigned Loci On Chromosome 6, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman Jan 1985

Linkage Relationships Between A New Locus, Hex2, And Previously Assigned Loci On Chromosome 6, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman

Jonathan F. Wendel

Starch gel electrophoresis of maize coleoptile extracts in our laboratory has shown two zones of staining for isozymes of hexokinase. Genetic analyses 9 indicate that the slower migrating set of bands is encoded by the structural gene Hex2 and that the enzyme is monomeric. Recent linkage analyses and work with B-A translocation stocks (generously supplied by Jack Beckett) have allowed for the placement ofHex2 on the long arm of chromosome 6. Its location relative to other markers on 6L was determined from the analysis of two very large F2 populations generated for other reasons.


Twelve New Isozyme Loci In Maize: Progress Report On Chromosomal Locations, The Subunit Composition, And Subcellular Localization Of Their Products, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman Jan 1985

Twelve New Isozyme Loci In Maize: Progress Report On Chromosomal Locations, The Subunit Composition, And Subcellular Localization Of Their Products, Jonathan F. Wendel, Charles W. Stuber, Major M. Goodman

Jonathan F. Wendel

To improve the degree to which the com genome is biochemically marked, we have expanded the number of enzyme systems analyzed by starch gel electrophoresis. Seven new enzyme systems encoded by a minimum of 16 loci have been added to the 23 loci used for previous work in our laboratory. A wide range of domestic and exotic maize has been screened for variation at these new loci and genetic analysis of variant electromorphs is well under way. Crosses with B-A translocation stocks (kindly provided by Jack Beckett), previously mapped allozyme loci, and in a few cases morphological markers, are being …


Genetic Divergence Within The Genus Liriodendron (Magnoliaceae), Jonathan F. Wendel, Clifford R. Parks, Norton G. Miller, Karen M. Mcdougal Jan 1983

Genetic Divergence Within The Genus Liriodendron (Magnoliaceae), Jonathan F. Wendel, Clifford R. Parks, Norton G. Miller, Karen M. Mcdougal

Jonathan F. Wendel

The genus Liriodendron L. consists of a southeast Asian-eastern North American disjunct species pair, but the genus had a much wider distribution in the Northern Hemisphere during the late Cretaceous and the Tertiary. Although generally similar in morphology, the two extant species are measurably different. In 1973 and 1977 they were hybridized, and interspecific heterosis was observed in the progeny. After seven years, the interspecific hybrids synthesized in 1973 had a significantly greater biomass than intraspecific hybrids of L. tulipifera. The growth rate of interspecific and intraspecific F2 seedlings was approximately equal. A preliminary survey of flavonoid extracts in L. …