Annual Forages: New Approaches for C-4 Forages

The current agricultural paradigm in the U.S. is heavily biased towards the production and marketing of crops as commodities. This paradigm is kept in place by grain handling and marketing infrastructure, as well as government farm programs, designed for crops as commodities. Sorghum (Sorghum bicolor L. Moench) and maize (Zea mays L.) grown for grain certainly fit into this current paradigm. A new approach to agricultural production and marketing, identity preserved products, is gaining in importance. This is made possible through new technologies and markets demanding products designed specifically for their needs. Examples of investment in identity preserved products include Pioneer Hi-Bred\u27s new research facility for grain quality (Johnson 1995), DuPont\u27s current emphasis on value-added maize (Freiberg 1994), and Iowa State University\u27s value-added grain marketing program (Wrage 1995). However, marketing strategies for such new grain products must be outside the current norm of sale to a local elevator and resale of a bulk commodity to grain consumers. Sorghum and maize grown for forage are already outside of the current marketing structure for grain crops. They are typically grown, stored, and fed on the same farm. Management decisions including choice of hybrids can be based on end use. As such, it could be argued that the current paradigm for production and utilization of forages in the United States, especially annual forages, is very favorable for the development and marketing of identity preserved hybrids and varieties designed for specific end users

Breeding Sorghum And Pearl Millet For Forage And Fuel

Sorghum [Sorghum bicolor (L.) Moench] and pearl millet [Pennisetum glaucum (L.) R. Br.] are unique species in their ability to be used in many forage llivestock system roles. Such flexibility has made prioritizing breeding objectives difficult and has even contributed to contradictory opinions on appropriate forage breeding objectives. Few breeding projects identified in the USDA-ARS, USDA-CREES, or at ICRISAT had forage sorghum or forage pearl millet as their sole research assignment. In the United States, it can be argued that breeding resources committed to forage sorghum improvement are probably declining. A new forage sorghum and forage pearl millet project recently considered by INTSORMIL did not receive high enough priority to receive funding from available resources. This paper discusses: new technologies, including automated harvesting systems, statistical methods, and forage quality assessment methods, that allow considerable increases in the scale and efficiencies of forage sorghum and millet breeding programs; examples of genes coding for characters known to impact forage quality; the status of the ethanol industry in general; the prospect for ethanol from biomass; and production of paper from stover. Due to limited resources, forage sorghum and millet breeding programs will have to focus on narrow, high impact objectives and utilize the best available technology

Annual Forages: New Approaches for C-4 Forages

The current agricultural paradigm in the U.S. is heavily biased towards the production and marketing of crops as commodities. This paradigm is kept in place by grain handling and marketing infrastructure, as well as government farm programs, designed for crops as commodities. Sorghum (Sorghum bicolor L. Moench) and maize (Zea mays L.) grown for grain certainly fit into this current paradigm. A new approach to agricultural production and marketing, identity preserved products, is gaining in importance. This is made possible through new technologies and markets demanding products designed specifically for their needs. Examples of investment in identity preserved products include Pioneer Hi-Bred\u27s new research facility for grain quality (Johnson 1995), DuPont\u27s current emphasis on value-added maize (Freiberg 1994), and Iowa State University\u27s value-added grain marketing program (Wrage 1995). However, marketing strategies for such new grain products must be outside the current norm of sale to a local elevator and resale of a bulk commodity to grain consumers. Sorghum and maize grown for forage are already outside of the current marketing structure for grain crops. They are typically grown, stored, and fed on the same farm. Management decisions including choice of hybrids can be based on end use. As such, it could be argued that the current paradigm for production and utilization of forages in the United States, especially annual forages, is very favorable for the development and marketing of identity preserved hybrids and varieties designed for specific end users

Evaluation of 41 elite and exotic inbred\u3ci\u3e Sorghum\u3c/i\u3e genotypes for high quality callus production

Interest is high in the genetic study and improvement of sorghum(Sorghum bicolor L. Moench), a crop of worldwide agronomic importance. The ability to initiate and maintain high quality (pigmentless, mucilage-free, fast growing, type II) callus cultures from a variety of sorghum genotypes is important for certain tissue culture-based genetic studies. The objective of this study was to identify high-quality callus-producing genotypes from a group of 41 diverse inbred sorghum lines. Callus cultures of 20 elite inbred sorghum genotypes and 21 inbred genotypes of exotic background were initiated from immature inflorescences. The cultures were subjected to several cycles of subculturing with selection for high quality callus growth, then rated for the callus quality traits pigment/tannin production, mucilage production, embryogenesis, and friability. Genotypic effects on each of the traits was highly significant. The range in quality of callus produced by different sorghum genotypes was large. Based on mean ratings assigned for each of the traits, 7 elite inbred genotypes and 5 nonelite genotypes were identified as producers of high quality callus

Media Effects On Phenotype Of Callus Cultures Initiated From Photoperiod-Insensitive, Elite Inbred Sorghum Lines

Sorghum (Sorghum bicolor L. Moench) is a crop of worldwide agronomic importance. Routine production of high quality (friable, embryogenic, fast growing) callus cultures is fundamental to tissue culture based genetic study and improvement of sorghum. Genotype by culture medium interactions for sorghum callus growth and morphology have been previously reported. The objective of this study was to identify tissue culture media that would support high quality callus growth across photoperiod insensitive, relatively elite genotypes. Explants from immature inflorescences of 11 sorghum genotypes were cultured on 6 tissue culture media of differing composition. After 3 and 5 months in culture, calli were rated for pigment and mucilage production, friability, and embryogenesis. Media and genotype effects on callus phenotype were highly significant. Most genotypes produced highest quality callus on MS-based media. Significant genotype by media interactions for callus friability were also documented. Two media formulations, SIM2B5 and N6 were identified as superior for the culture of high quality callus initiated from photoperiod insensitive, elite sorghum lines

Media Effects On Phenotype Of Callus Cultures Initiated From Photoperiod-Insensitive, Elite Inbred Sorghum Lines

Sorghum (Sorghum bicolor L. Moench) is a crop of worldwide agronomic importance. Routine production of high quality (friable, embryogenic, fast growing) callus cultures is fundamental to tissue culture based genetic study and improvement of sorghum. Genotype by culture medium interactions for sorghum callus growth and morphology have been previously reported. The objective of this study was to identify tissue culture media that would support high quality callus growth across photoperiod insensitive, relatively elite genotypes. Explants from immature inflorescences of 11 sorghum genotypes were cultured on 6 tissue culture media of differing composition. After 3 and 5 months in culture, calli were rated for pigment and mucilage production, friability, and embryogenesis. Media and genotype effects on callus phenotype were highly significant. Most genotypes produced highest quality callus on MS-based media. Significant genotype by media interactions for callus friability were also documented. Two media formulations, SIM2B5 and N6 were identified as superior for the culture of high quality callus initiated from photoperiod insensitive, elite sorghum lines

Notes: Forage Yield, Quality, And Fertility Of Sorghum X Sudan Grass Hybrids In A1 And A3 Cytoplasm

Currently, no information is available comparing the agronomic performance of A1 and A3 cytoplasms in sorghum x sudangrass [Sorghumbi color (L.) Moench] hybrids. The objectives of this study were to compare the effects of A1 and A3 cytoplasm on the maturity, fertility, height, forage yield, and forage quality of sorghum × sudangrass hybrids. In 1989, pollen from a bulk of eight sudangrass populations was used to pollinate four sorghum lines that had been male-sterilized in both A1 and A3 cytoplasm. Hybrids were grown at the Univ. of Nebraska Field Laboratory Ithaca, NE, in 1990 and 1991, in a split-plot design with inbreds (females) treated as whole plots and cytoplasms treated as subplots. The soil was a Sharpsburg silty clay loam (fine montmorillonitic, mesic Typic Agriudoll). Cytoplasm had no effect on days to 50% anthesis, height, forage yield, in vitro dry matter disappearance (IVDMD) or, crude protein. Seed set under selfing bags( fertility restoration) in A3 hybrids was observed, with interaction among A3 cytoplasm sources and lines

Genetic manipulation of tall fescue

Genetic manipulation of tall fescue (Festuca arnndinacea Schreb.) has not been altered by the discovery of the Acremonium coenophialum (Morgan-Jones and Gams) / grass interaction. However, tall fescue breeding programs have been affected greatly. The basic methods for genetically manipulating the grass have remained static. Tall fescue is an obligate out-crossing species, and most improvements are, therefore, captured in the form of an improved population developed through some form of mass or recurrent selection. What has changed is the breeder\u27s ability to recognize genetic differences in the grass because of the confounding effect of A. coenophialum on plant phenotype. It is, therefore, critical that breeders recognize A. coenophialum status in their plants prior to selection. The other major change in tall fescue breeding since the discovery of the A. coenophialum/grass interaction is a tremendous increase in breeding activity

Growth And Magnesium Uptake Of Tall Fescue Lines At High And Low Potassium Levels

Five tall fescue (Festuca arundinacea Schreb.) clonal lines with diverse root and xylem diameters were grown in nutrient solutions with magnesium (Mg) concentrations of 42, 125 and 250 µm and potassium K concentrations of 133 and 333 µm. Leaf Mg concentrations increased with increasing Mg rates at both low and high K concentrations. The tall fescue line with the largest root and xylem diameters had low leaf Mg concentrations, indicating a possible increased Mg tetany potential when consumed by cattle. The response of the K/(Mg+Ca) ratio in the plant, an indicator of tetany potential, to varying solution Mg at low and high K was determined for each of the five lines. No Hg effects or interactions were significant. Line, K, and line x K effects were all significant for the K/(Mg+Ca) ratios. The line with the largest root and xylem diameters had the highest tetany potential (highest cation ratio). Higher solution K gave higher K/(Hg+Ca) ratios

Considerations in Breeding Endophyte-Free Tall Fescue Forage Cultivars

Breeding tall fescue (Festuca arundinacea Schreb.) cultivars that are free of the endophytic fungus Acremonium coenophialum Morgan-Jones and Gams [previously identified and referred to as Epichloe typhina (Fries) Tulasne] is necessary to improve animal performance. The techniques used in developing new cultivars are not greatly different from those used previously, with one exception. Prior to the evaluation of new tall fescue lines or populations, the endophyte needs to be eliminated from the seed or the plants. Several techniques utilizing aging, heat, or chemical treatment are being used to effectively accomplish this in the seed. Methods for permanently eliminating the endophyte from plants are not available. The major new considerations in breeding endophyte-free tall fescue cultivars do not involve drastic changes in breeding methodology, but rather focus on new objectives. In the past, much effort was directed at overcoming the toxic effects of the endophyte. Now, breeders can focus their efforts on objectives such as increasing digestibility, physiological efficiency, mineral uptake, and insect and disease resistance. Losses in stress tolerance due to the elimination of the endophyte from tall fescue may also have to be addressed, especially in areas of marginal adaptation