Life Sciences Commons^™

Carbon Dioxide Exchange Rate Of Tall Fescue-Leaf Area Vs. Leaf Weight Basis, Wallace Wilhelm, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The basis used for expression of carbon dioxide exchange rate (CER) of single leaves may alter the relative ranking of genotypes being selected for a breeding program. Therefore, field and growth chamber experiments were conducted on 16 genotypes of tall fescue (Festuca arundinacea Schreb.) to determine the relative merit of expressing CER data on a leaf area or leaf weight basis. Genotypes were grown in plots in the field and in pots in the growth chamber. The CER was measured using an infrared gas analyzer. Herbage yield was determined. Significant genotypic variation within experiments was found for CER when …

Herbicide Effects On Cultivars Of Soybeans [Glycine Max (L.) Merr.], Mark Martin

Masters Theses & Specialist Projects

Breeding herbicide-tolerant cultivars is a means of extending herbicide utilization. In 1983 and 1984, 20 soybean [Glycine max (L. Merr] cultivars were screened for their reactions to the following herbicides: metribuzin 4-amino-6-(tert)-butyl-3-(methylthio)-astriazin-5-(4H)-one]; vernolate (S-propyl dipropylthiocarbamate); and fluchloralin [N-(2-chloroethyl)-2,6-dinitro-N-propyl-4-(trifluoromethyl) aniline]. Each herbicide was applied at the recommended rate X, 2X, and 4X in 1983. An 8X rate was added in 1984. The recommended rates (X) for the herbicides were as follows: metribuzin 0.42, vernolate 2.80, and fluchloralin 1.12 kg/ha. The cultivars were Pella, Pixie, Cumberland, Williams, Essex, Union, Semmes, Tracy, Tracy M; North American Plant Breeders 350, 68225, 420, and …

Ultrastructural Effects Of Sethoxydim On The Intercalary Meristem Of Johnsongrass (Sorghum Halpense), Bobbie Dowden

Masters Theses & Specialist Projects

This investigation represents one of the first electron microscopic studies on determining the mode of action of the chemical herbicide sethoxydim, 2-[-1-(ethoxydimino)butyl] -5-.2-(ethiothio)propyl]-3- hydroxy-2-cyclohexen-1-one. Samples were excised from the intercalary meristem of johnsongrass (Sorghum halpense) at time intervals of 1,3, 6,12,24,36,48,60, and 72 hours and examined using electron microscopy. Transmission electron micrographs revealed that cellular activity shows alterations or abnormalities as early as six hours. Membranes show deterioration at this time and chloroplasts contain densely staining starch granules. As time intervals increase, cellular degradation becomes more evident. Nuclear membranes extend outward into the cytoplasm in various types of …

Tillage And Low-Pressure Center-Pivot Irrigation Effects On Corn Yield, Wallace Wilhelm, L.N. Mielke, J. R. Gilley

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Low-pressure sprinkler irrigation systems have the potential to save energy, but also may aggravate soil- and water-management problems. The objective of this research was to determine the influence of center-pivot sprinkler irrigation method in combination with various tillage practices on corn (Zea mays L.) yield and yield components. A center-pivot irrigation machine was designed to apply water by high-pressure-impact (HPI), low-pressure-impact (LPI), and low-pressure-spray (LPS) nozzles. Nozzles were sized and spaced to apply three different amounts of water: 100% (full irrigation), 75 and 50%. Three tillage treatments were used-till-plant (T), disk (D), and till-plant with chisel after last cultivation …

Intsormil 1985 Annual Report: Fighting Hunger With Research, John M. Yohe

INTSORMIL Impacts and Bulletins

This annual report covers the activities for program Year 6, the final year of operation under the initial grant document.

The CRSP's present a unique model for conducting agricultural research in collaboration with developing country agricultural research programs.

The INTSORMIL program also demonstrates these characteristics:

-- INTSORMIL has the dual goal of improving agriculture in the developing countries and in the United States.

- The seven participating U.S. institutions agree to contribute at least 25% of the cost of the CRSP from non-federal resources (in money or in kind), justified on the basis of benefits that can accrue to their …

Cryogenic Preservation Of Semen From The Greater Sandhill Crane, George F. Gee, Murray R. Bakst, Thomas J. Sexton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Frozen gene pools (semen or embryos) can provide a safe place for the storage of genetic material for many generations. Cranes (Grus spp.) are one of many species in need of gene pool protection. Of the seven species and four subspecies considered rare or endangered (Archibald et al. 1981), two, the whooping crane (G. americana) and the Mississippi sandhill crane (G. canadensis pulla), are part of captive propagation projects at the Patuxent Wildlife Research Center in Laurel, Maryland. Greater sandhill crane (G. c. tabida) semen cryopreservation, under study at Patuxent since 1976 (Sexton …

Blueberry Advisory Committee Research Report, H Y. Forsythe Jr, Jeffrey Holmes, F L. Caruso, M G. Zuck, John M. Smagula, Edward J. Mclaughlin, Jeff Risser, Mike Goltz, Dana Nelson, Sharon Roberts, Judy Gates, Moody F. Trevett, Tom Cs Yang, David E. Yarborough, Antonia L. Hoelper, D C. Emerson

Wild Blueberry Research Reports

The 1984 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:

1. Control, biology, and ecology of insects affecting lowbush blueberries .

2. Chemical control of mummyberry disease (Monilinia vaccinii-corymbosi)

3. New Fungicides for control of Botrytis blossom blight

4. Nutritional survey of selected lowbush blueberry fields

5. Interaction of fertility and pruning practices on soil characteristics and lowbush blueberry growth and …

Twenty-Four-Hour Profiles Of Prolactin And Testosterone In Ram Lambs Exposed To Skeleton Photoperiods Consisting Of Various Light Pulses, B. D. Schanbacher, W. Wu, J. A. Nienaber, G. L. Hahn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Individual groups of 6 ram lambs were housed within a controlled environment and exposed to one of 6 photoperiod schedules. Groups I and II received 8 (short day) or 16 (long day) h of continuous light, respectively; Groups III, IV and V were exposed to asymmetrical skeleton photoperiods consisting of a main light period of 7 h followed 9 h later by a light pulse of 1 h, 15 min or 1 min duration, respectively, and Group VI was exposed to a symmetrical skeleton photoperiod consisting of two 1-h light pulses positioned 16 h apart. After 4 weeks of treatment …

Facing A Drought, J A C Smith

Bulletins 4000 -

This booklet is aimed at helping you decide on strategies, in this and future droughts, in relation to money flow, animal management and cropping. It highlights the technical problems associated with different strategies and how to combat them.

Corn Response To Sulfur On Illinois Soils, R. G. Hoeft, J. E. Sawyer, R. M. Vanden Heuvel, M. A. Schmitt, G. S. Brinkman

John E. Sawyer