Life Sciences Commons^™

Cornposting Converts Waste Into Valuable Resources, Leon Chesnin

Department of Agronomy and Horticulture: Faculty Publications

Rural and urban communities and farms have at least one problem in common: the accumulation of various organic wastes. Farms produce wastes such as animal manures, and crop residues such as straw, corn cobs, hay stack bottoms and spoiled silage.
In Nebraska's towns and cities, the organic wastes include sewage sludge, paunch manure from slaughter houses, and garbage originating from household foods and paper.
Some of these organic wastes are associated with the nuisances of flies, odors and dust. Fresh animal manures, paunch manure, sewage sludge and garbage are favorite breeding places for flies. Flies are attracted to odors and …

Interactions Between Insects And Chemical Components Of Sweetclover, G. R. Manglitz, Herman J. Gorz, Francis A. Haskins, W. R. Akeson, G. L. Beland

Department of Agronomy and Horticulture: Faculty Publications

This review concerns the relationship between chemical components found in sweetclover [Melilotus officinalis (L.) Pall. and M. alba Desr.] tissues and insects feeding on these tissues. Coumarin and its related compounds did not appear to influence the feeding of sweetclover aphids [Therioaphis riehmi [Börner)], pea aphids [Acyrthosiphum pisum (Harris)] or potato leafhoppers [Empoasca fabae (Harris)] , however, these materials appeared attractive to sweetclover weevils (Sitona cylindricollis Fåhraeus) and to adult sweetclover root borers [Walshia miscecolorella (Chambers)]. Conversely the feeding of four species of blister beetles (Epicauta sp.] was inhibited by cis-o-hydroxycinnamic acid …

Genetic Regulation Of Flavonoid Content In Seeds And Seedlings Of Melilotus Alba, James E. Specht, Herman J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Chemical analysis of seeds and seedlings of the CC and cc genotypes in Melilotus alba indicated that these alleles affect flavonoid biosynthesis. The CC seed coats contained orientin and iso-orientin, which were absent in the cc seed coats. The pigment responsible for the red pigmentation of young seedlings of CC genotypes was a cyanidin glycoside. The embryos of seeds of both the CC and cc genotypes contained a flavonoid tentatively identified as a 6,8-di-C-pentosylapigenin. The observation that 3',4'-dihydroxyflavonoids were absent in the cc genotype and that 4'-hydroxyflavonoids were present in both genotypes indicated that the C/c alleles controlled the 3'-hydroxylation …

Contents Of Chlorophylls A And B In Chlorophyll-Deficient Mutants Of Sweetclover, James E. Specht, Francis A. Haskins, H. J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Leaf extracts from twelve chlorophyll-deficient mutants of sweetclover (Melilotus alba Desr.) were compared spectrophotometrically and chromatographically with extracts from normal plants to determine contents of chlorophylls a and b Total chlorophyll contents in cotyledons and leaves of all mutants were significantly lower than those in corresponding tissues of normal plants. Chlorophyll contents were generally higher in later emerging leaves of both normal and mutant plants. Chlorophyll alb ratios in first trifoliolate leaves were similar to normal in mutants ch₇ and ch₈, higher in mutants ch₈, ch₉, ch₁₀, and ch_{11 …}

Seedling Growth Of Three Switchgrass Strains, L. J. Perry Jr., Lowell E. Moser

Department of Agronomy and Horticulture: Faculty Publications

Seedlings of Pathfinder, Nebr. 28, and experimental ey switchgrass (Panicum virgatum L.) strains were grown in a growth chamber and harvested 1, 2, 3, 4, 6, 8, and 10 weeks following emergence for detection of seedling growth differences among strains. Leaf areas and dry weights of leaf blade and stem axis (stem and leaf sheath) generally increased significantly with each harvest from 4 to 10 weeks. Stem axis and leaf blade dry weights were significantly greater with Pathfinder and ey, respectively, than with Nebr. 28. Final leaf area was significantly greater with ey than with the other strains. Thus, …

Inheritance Of Seed And Seedling Color In Sweetclover, H. J. Gorz, James E. Specht, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Eight seed colors, conditioned by two independent pairs of genes, were identified in sweetclover (Melilotus alba Desr.). The seed colors resulted from all combinations of two embryo and four seed coat phenotypes. Only four of the seed colors were recoverable in true-breeding form. Conventional genetic tests revealed that Y /y alleles determined the absence or presence, respectively, of green pigmentation in both the embryo and seed coat of fully mature seeds. Absence of green was dominant in both seed parts. The C/c alleles conditioned the presence or absence, respectively, of brownish pigmentation in the seed coat and red pigmentation …

Genetic Studies Of Induced Mutants In Melilotus Alba. Iv. Inheritance And Complementation Of Six Additional Chlorophyll-Deficient Mutants, R. R. Ronnenkamp, H. J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Six ethyl methanesulfonate-induced chlorophyll-deficient mutants of Melilotus alba Desr. were studied. Each of the mutants behaved as a monogenic recessive. Complementation analysis revealed that the genes from five of the mutants were nonallelic to each other and to the previously reported mutants ch₄, ch₅, ch₆, and ch₇ Proposed symbols for the five genes are ch₈, ch₉, ch₁₀, ch₁₁, and ch₁₂. No linkage was detected between ch₅ and ch₇, ch₇ and M_f, (multifoliolate leaf), ch₈ and ch …

Resistance Of Red Clover To The Clover Leaf Weevil, H. J. Gorz, G. R. Manglitz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Red clover (Trifolium pretense L.) varieties in the third season of growth, that had been exposed to a heavy infestation of larvae of the clover leaf weevil [Hypera punctata (Fabricius)], differed significantly in percentage defoliation, feeding injury score, plant height, and forage production. Based on these four characters, 'Mammoth,' 'Lakeland,' 'Dollard,' and 'LaSalle' were highly resistant to larval feeding; 'Kenland,' 'Common,' and 'Pennscott' were highly susceptible. Long term second-season yield tests including six of these varieties indicated no con• sistent superiority of any of the varieties in the absence of weevil feeding.

Genetic Studies Of Induced Mutants In Melilotus Alba. Iv. Inheritance And Complementation Of Six Additional Chlorophyll-Deficient Mutants, R. R. Ronnenkamp, Herman J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Six ethyl methanesulfonate-induced chlorophyll-deficient mutants of Melilotus alba Desr. were studied. Each of the mutants behaved as a monogenic recessive. Complementation analysis revealed that the genes from five of the mutants were nonallelic to each other and to the previously reported mutants ch₄, ch₅, ch₆, and ch₇. Proposed symbols for the five genes are ch₈, ch₉, ch₁₀, ch₁₁, and ch₁₂. No linkage was detected between ch₅ and ch₇, ch₇, and M_f, (multifoliolate leaf), ch_{8 …}

Influence Of Seed Size, Planting Depth, And Companion Crop On Emergence And Vigor Of Seedlings In Sweetclover, Francis A. Haskins, Herman J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Seed size has been shown to have an important influence on the emergence and early growth of seedlings of several forage legumes, but only fragmentary information on seed size effects in sweetclover (Melilotus spp.) has been published. Therefore, a 2-year study was conducted in which spring and fall seedings of small, medium, and large seeds of 'Madrid' and 'N13' sweetclover (Melilotus officinalis (L.) Lam.) were made at depths of 19, 38, and 57 mm. The spring seeding also included a comparison of a companion crop (oats) with no companion crop. Data on emergence score and plant height were …

Carbohydrate And Organic Nitrogen Concentrations Within Range Grass Parts At Maturity, L. J. Perry Jr., Lowell E. Moser

Department of Agronomy and Horticulture: Faculty Publications

Total nonstructural carbohydrate (TNC) levels were significantly different among eight range grasses at maturity. Roots, rhizomes, and stem bases (storage organs), differed significantly in percentage TNC within rhizomatous and bunch-type (non-rhizomatous) grasses. Percent organic nitrogen differed significantly among grasses and storage organs but not to the same extent as with TNC. We of nonstructural polysaccharide accumulated (Smith, 1968; suggest that TNC concentrations of storage organs must be determined for each grass before sampling for TNC levels, in Grasses of subtropical order to locate storage organs with greatest TNC concentration.

Lysimetric Calibration Of The Bowen Ratio-Energy Balance Method For Evapotranspiration Estimation In The Central Great Plains, Blaine L. Blad, Norman J. Rosenberg

Department of Agronomy and Horticulture: Faculty Publications

Most reports show good agreement between evapotranspiration (ET) rates estimated by Bowen Ratio-Energy Balance (BREB) method and rates measured with lysimeters, although underestimation by the BREB model has occasionally been reported. This study was conducted to evaluate the performance of the BREB technique in the climatic conditions characteristic of the central Great Plains, a region where a significant proportion of the energy consumed by evapotranspiration is supplied from advected sensible heat.

Agreement between the BREB method and lysimetric measurements of ET is good during non-advective periods but during advective periods the BREB model underestimates ET by about 20%. Data collected …

Sweetclover Weevil: Adenosine As A Feeding Stimulant, G. L. Beland, Francis A. Haskins, G. R. Manglitz, Herman J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Adult Sitona cylindricoIlis Fåhraeus responded to adenosine in bioassays for feeding-stimulant activity. The molar concentration of adenosine which elicited maximum feeding in the bioassay was less than 1/10 of the sucrose concentration required for maximum feeding. Various purines, pyrimidines, nucleosides, nucleotides, and related compounds were compared with adenosine in bioassays for weevil-feeding stimulant activity. Of all compounds tested, only adenosine triphosphate and adenosine monophosphate appeared to act as feeding stimulants; at the concentrations used, their activities were substantially lower than that of adenosine. Free adenosine was isolated from leaf extracts of weevil-susceptible Melilotus officinalis (L.) Lam. by ion-exchange and paper …

Influence Of Tissue Drying On O-Hydroxycinnamic Acid Content In Sweetclover, Francis A. Haskins, Herman J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

A fluorometric procedure was used to study changes in levels of the free and bound forms of the cis and trans isomers of o-hydroxycinnamic acid (o-RCA) associated with drying sweetclover (Melilotus) tissues under various conditions of time and temperature. Leaves, or leaves and stems, of three sweetclover varieties, 'Spanish,' 'Evergreen,' and 'Goldtop,' and two closely related, highly inbred lines (CuCuBB and CuCubb genotypes) were used. Drying temperatures of 30 and 40 C were used most extensively. When dried at 30 C, leaves lost more than half of their bound cis-o-RCA, and a small …

Genetic Studies Of Induced Mutants In Melilotus Alba Iii. Folded Leaflet, Elongatyed Stem, And Short-Petiole Dwarf, R. R. Ronnenkamp, Francis A. Haskins, Herman J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Observations of the F₁, F₂, and F₃ progenies of crosses between normal annual Melilotus alba Desr. and three mutants, folded leaflet, elongated stem, and short-petiole dwarf, indicate that each of the mutant characters is controlled by a single recessive gene. Proposed symbols for the three mutant genes are f, el, and d_sp, respectively. In limited tests for linkage, el appeared to be linked (12% recombination) to a gene for multifoliolate leaves (Mf). No linkage was detected between f and Mf, cu (low o-hydroxycinnamic acid), or b (low …

Effect Of Coumarin And Related Compounds On Blister Beetle Feeding In Sweetclover, Herman J. Gorz, Francis A. Haskins, G. R. Manglitz

Department of Agronomy and Horticulture: Faculty Publications

The ashgray blister beetle, Epicauta fabricii (LeConte); the striped blister beetle, E. vittala (F.) ; and the margined blister beetle, E. pestifera Werner collected in the field from plants of sweetclover low in coumarin content, fed preferentially in the Iaboratory on low-coumarin leaves when offered a choice between leaves from highand low-coumarin plants. The black blister beetle, E. pennsylvanica (De Geer) , not known to feed 011 sweetclover foliage, also fed preferentially in the laboratory on leaves from low-coumarin plants, although the rate of feeding was much slower than for the other species. By using appropriate genotypes of sweetclover and …

Form And Level Of Coumarin In Deer's Tongue, Trilisa Odoratissima, Francis A. Haskins, H. J. Gorz, R. C. Leffel

Department of Agronomy and Horticulture: Faculty Publications

Fresh leaves of deer's tongue contain large quantities (more than 10% of the dry weight, in some cases) of o-hydroxycinnamic acid (o-HCA). Both cis- and trans-o-HCA are present, and both isomers exist in the fresh tissue predominantly as glucosides. Cured deer's tongue leaves contain relatively high levels of coumarin and lower amounts of o-HCA glucosides. It is probable that during the curing process cis-o-HCA glucoside is hydrolyzed by an endogenous g-glucosidase, and that the liberated cis-o-HCA lactonizes spontaneously to form coumarin.

Solubility Of (Β-Glucosidase In Homogenates Of Sweetclover Leaves And Bean Hypocotyls, T. A. Jaynes, Francis A. Haskins, H. J. Gorz, A. Kleinhofs

Department of Agronomy and Horticulture: Faculty Publications

In a recent paper Eberhart and Beck (4) suggested that the aryl-,β-glucosidase of Neurospora conidia is a mural enzyme. Similarly, Nevins (11) reported that ,β-glucosidase is strongly associated with cell walls during extraction of bean hypocotyls at pH 4.6 and suggested that this enzyme is wall-bound in situ, and Keegstra and Albersheim (9) noted that β-glucosidase could be effectively washed from the surface of sycamore cells grown in liquid culture. On the basis of histochemical evidence, Ashford (1) suggested that β-glucosidase in corn roots is associated with a reticulate network of strands and particles, and Ashford and McCully (2) …

Oxidation Of Phenylpyruvate By Sweetclover Peroxidase, T. A. Jaynes, Francis A. Haskins, H. J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Sweetclover (Melilotus alba Desr.) contains a soluble enzyme which oxidizes phenylpyruvate with the addition of either a natural cofactor or Mn²⁺ and dichlorophenol. The final product of oxidation has not been identified. Phenylpyruvate oxidation is catalyzed also by horseradish peroxidase, and the oxidation is enhanced by the natural cofactor from sweetclover or Mn²⁺ and dichlorophenol. After fractionation of sweetclover homogenates by DEAE-cellulose chromatography, two peaks of peroxidase activity (pyrogallol as substrate) are apparent; both peaks also oxidize phenylpyruvate. A third peak, specific for phenylpyruvate oxidation, also is apparent. The Cu/cu and B/b allelic pairs, which influence phenolic …

Form And Level Of Coumarin In Deer's Tongue, Trilisa Odoratissima, Francis A. Haskins, H. J. Gorz, R. C. Leffel

Department of Agronomy and Horticulture: Faculty Publications

Fresh leaves of deer’s tongue contain large quantities (more than 10% of the dry weight, in some cases) of o-hydroxycinnamic acid (o-HCA). Both cis- and trans-o-HCA are present, and both isomers exist in the fresh tissue predominantly as glucosides. Cured deer’s tongue leaves contain relatively high levels of coumarin and lower amounts of o-HCA glucosides. It is probable that during the curing process cis-o-HCA glucoside is hydrolyzed by an endogenous β-glucosidase, and that the liberated cis-o-HCA lactonizes spontaneously to form coumarin.

Penstemon In Your Garden [Revised], Roger D. Uhlinger, Glenn Viehmeyer

Department of Agronomy and Horticulture: Faculty Publications

The Genus Penstemon

Penstemon Breeding: Emasculation • Pollen Collection • Pollination • Keeping Records

Selection of ParentaI MateriaIs

Species Crosses

Breeding Behavior

Sources of Breeding Material

Penstemon Propagation: Propagation by Seed • Propagation by Division and Layering • Propagation by Cuttings • Tip Cuttings • Single Node and Single Eye Cuttings • Striking the Cuttings • Rooting Mediums • Setting the Cuttings

Penstemon Diseases : Leaf Diseases • Soil Borne Diseases • Virus Diseases

Insects that Affect Penstemon: Aphids • Cutworms • False Plant Bug • Flea Beetle • Grasshoppers • Leaf hoppers • Slugs • Red Spider Mites • …

Influence Of Iron Supply On Peroxidase Activity And Peroxidase Isozymes In Corn (Zea Mays), R. L. Ulmer, Francis A. Haskins, W. R. Akeson

Department of Agronomy and Horticulture: Faculty Publications

Plants of Oh43 X Wf9 corn (Zea mays L.), grown in a sand culture system, were watered daily with nutrient solution containing 0.025, 1.25, or 2.5 ppm Fe. Plants also were grown in a soil-sand mixture. Leaf extracts were assayed quantitatively for peroxidase activity, and samples of the extracts were subjected to gel electrophoresis. A positive relationship was observed between Fe supply and proxidase activity. Numerous peroxidase isozymes were detected by gel electrophoresis. As judged by intensity of the bands, all isozymes appeared to be infIuenced by Fe supply.

Evaluation Of Cross-Fertilization In Forage Crops, Herman J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

In the improvement of forage crop varieties knowledge of the extent of cross-fertilization is of value for (1) determining the extent and randomness of crossing in breeding procedures, (2) estimating varietal changes due to contamination and mechanical mixtures, and (3) evaluating effects of cross-fertilization in the development and production of synthetic and hybrid combinations. Genetic markers can aid greatly in the evaluation of cross·fertilization, and thus in the development and production of new varieties. Ideally, markers should be distinctive and readily detected in the seedling stage, conditioned by a single dominant gene with complete penetrance, and have no adverse effects …

Cross-Fertilization In Melilotus Alba, Herman J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Two simply inherited characters, o-hydroxycinnamic acid (o-HCA) content and β-glucosidase activity, were used as genetic marker s in studying the frequency of cross-fertilization in Melilotus alba Desr. Based on the o-HCA marker, the effective cross-fertilization averaged 58% for two harvest years in a biennial population and 67% in a 1-year study with an annual population. Use of the β-glucosidase marker provided a cross-pollination estimate of 72% in the biennial population. The extent of natural crossing in sweetclover appears to be sufficient to restore normal vigor in the production of varieties synthesized from selected inbred lines.

Sweetclover Weevil Feeding Stimulants: Variation In Levels Of Glucose, Fructose, And Sucrose In Melilotus Leaves, W. R. Akeson, H. J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Youngest fully expanded leaves, from plants of M. Officinalis (L.) Lam. seeded at weekly intervals but harvested on the same day, were approximately 1.5 to 2.0 times as high in content of glucose, fructose, and sucrose at all stages of growth as leaves from comparable plants of M. infesta Guss. These plants varied in age from 3 to 14 weeks. Levels of glucose and fructose increased with increasing plant age in both species. Sucrose content increased in M. officinalis but decreased in M. infesta as the plants matured. When plants of approximately the same age were sampled at six different …

Rapid Detection Of O-Hydroxycinnamic Acid And Beta-Glucosidase In Melilotus Alba, Francis A. Haskins, H. J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

The tests utilize small samples of leaf tissue crushed on sheets of filter paper. For detection of o-hydroxycinnamic acid (o-HCA), a crude preparation containing sweetclover β-glucosidase is added to a spot of crushed tissue to insure hydrolysis of glucosidically bound o-HCA. An extract containing cis-o-HCA glucoside is added to another tissue spot to serve as the substrate for the detection of β-glucosidase activity. Finally, all spots are moistened with NaOH and are scored for fluorescence under ultraviolet light. Results of qualitative and quantitative tests on plants representing various genotypes are compared. The importance of exposing plants to sunlight before testing …

Fluorometric Assay Of Free And Bound, Cis- And Trans-O-Hydroxycinnamic Acid In A Single Plant Extract, Francis A. Haskins, H. J. Gorz

Department of Agronomy and Horticulture: Faculty Publications

Fluorescence is measured on unhydrolyzed and hydrolyzed plant extracts, with and without prior ultraviolet treatment. Readings permit direct determination of free o-hydroxycinnamic acid (o-HCA), free trans-o-HCA, total o-HCA, and total trans-o-HCA. Levels of bound trans-o-HCA and free and bound cis-o-HCA are calculated by appropriate subtraction.

Feeding Responses Of The Sweetclover Weevil To Various Sugars And Related Compounds, W. R. Akeson, Francis A. Haskins, Herman J. Gorz, G. R. Manglitz

Department of Agronomy and Horticulture: Faculty Publications

The sweetclover root disk bioassay was used to test the activity of 21 sugars and related compounds as feeding stimulants for the sweetclover weevil Sitona cylindricollis Fähraeus. Of the compounds tested, sucrose was the most effective feeding stimulant. Compounds with moderate stimulant activity were fructose, glucose, galactose, mannose, myo-inositol, and maltose. Slightly active feeding stimulants included ribose, xylose, sorbose, and sedoheptulose. Arabinose, arabitol, mannitol, xylitol, cellobiose, raffinose, soluble starch, ascorbic acid, glucuronic acid, and glucosamine failed to exhibit feeding stimulant activity in these tests, Four compounds (arabinose. ascorbic acid, glucuronic acid, and mannitol) were tested for feeding deterrent activity, and …

Genetic Studies Of Induced Mutants In Melilotus Alba. Ii. Inheritance And Complementation Of Chlorophyll-Deficient Mutants, B. G. Gengenbach, H. J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

Six ethyl methanesulfonate-induced mutants of Melilotus alba Desr. were studied. Five of the mutants behaved as monogenic recessives. In the sixth mutant, two independent recessive alleles were responsible for the observed phenotype. Of these two genes, one had a phenotypic effect similar to the five single-gene mutants. The other (the veined gene) caused a chlorophyll deficiency in which the leaf veins were darker in color than the tissue between the veins. Complementation analysis revealed that five of the seven genes detected iu the mutants were nonallelic. Suggested designations for the five genes are ch₄, ch₅, ch …

Sweetclover Weevil Feeding Stimulants: Isolation And Identification Of Glucose, Fructose, And Sucrose, W. R. Akeson, H. J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

The water-soluble fraction of Melilotus leaves previously referred to as Stimulant A was further fractionated by preparative paper chromatography into three factors, each having a stimulatory effect on sweetclover weevil feeding. The three factors, designated Stimulant A₁, A₂, and A₃, were identified as sucrose, glucose, and fructose, respectively, by co-chromatography with known sugars on cellulose-coated thin-layer plates. Silver nitrate, anisidine phthalate, and anthrone were employed as detection agents. The isolated compounds and corresponding reagent grade sugars were identical in chromatographic and chemical behavior, as well as in feeding stimulant activity. Sucrose stimulated the greatest …