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2006

Iowa State University

Agricultural Science

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Diversity And Efficacy Of Arbuscular Mycorrhizal (Am) Fungi Isolated From Soils Of Soybean Fields , Zahra Ifnou Troeh Jan 2006

Diversity And Efficacy Of Arbuscular Mycorrhizal (Am) Fungi Isolated From Soils Of Soybean Fields , Zahra Ifnou Troeh

Retrospective Theses and Dissertations

A field survey evaluated the population composition of AM fungal species in Clarion (a well drained fine-loamy, mixed, mesic Typic Hapludoll) and Webster (a poorly drained fine-loamy, mixed, mesic Typic Endoaquoll) soils of four Iowa soybean (Glycine max, L.) fields. Spores from six species of Glomus and from the genera Acaulospora, Gigaspora , and Paragomus were found in the original field soils. G. claroideum, G. etunicatum, G. mosseae, G. viscosum, and Paraglomus occultum-like spores were prevalent in both Clarion and Webster soils of all four fields. Minor species included G. geosporum and G. intraradices. Trap cultures led to detection of several ...


The Quantitative Genetics Of A Non-Stiff-Stalk Maize (Zea Mays L) Population , Brandon M. Wardyn Jan 2006

The Quantitative Genetics Of A Non-Stiff-Stalk Maize (Zea Mays L) Population , Brandon M. Wardyn

Retrospective Theses and Dissertations

The genetic relationship among individuals is at the core of nearly all quantitative genetic theory. Dominant gene action has long been either ignored or disregarded as insignificant in many previous genetic models. For grain yield in maize (Zea mays L.), dominance has consistently accounted for a large proportion of genetic variance. We have used previously developed genetic theory that accounts for dominance variance during inbreeding and applied it to a unique breeding design. Our breeding design allowed us to estimate five genetic covariance parameters for six traits. In addition, we developed genetic gain equations that accounted for both dominance and ...


Management Of Grape Colaspis, Colaspis Brunnea (Coleoptera: Chrysomelidae), In Seed Corn Production , Benjamin Carl Kaeb Jan 2006

Management Of Grape Colaspis, Colaspis Brunnea (Coleoptera: Chrysomelidae), In Seed Corn Production , Benjamin Carl Kaeb

Retrospective Theses and Dissertations

In recent years, grape colaspis, Colaspis brunnea (F.), larvae have caused significant injury to seed corn by feeding on the surface of the root, denuding it of root hairs. This study tested two management techniques for C. brunnea in seed corn. The first objective was to test the efficacy of commercially available insecticides, specifically neonicotinoid seed treatments, in protecting commercial seed corn from C. brunnea larval injury. The results of this study showed insecticides offer protection to the seedling corn from C. brunnea larvae; however, no insecticide treatment significantly outperformed any other. The second objective was to develop and test ...


Management Of Urd Bean Leaf Crinkle Virus In Urd Bean (Vigna Mungo L. Hepper), Ch Ravinder Reddy, Vilas A. Tonapi, S. Varanavasiappan, Shrishail S. Navi, R. Jarayajan Jan 2006

Management Of Urd Bean Leaf Crinkle Virus In Urd Bean (Vigna Mungo L. Hepper), Ch Ravinder Reddy, Vilas A. Tonapi, S. Varanavasiappan, Shrishail S. Navi, R. Jarayajan

Plant Pathology and Microbiology Publications

Six plant extracts viz , Mirabtlis jalapa, Carthamus roseus. Datura metal, Bougainvitlea spectabilis, Boerhaavia diffusa and Azadirachta indica recorded maximum reduction in the incidence of urd bean leaf crinkle virus (ULCV) in urd bean crops at field level Among the antiphytovirat chemicals tested, DHT reduced the transmission to the maximum extent and increased the incubation period of virus in the urd bean plant Fresh buttermilk was significantly superior to fermented buttermilk in reducing the disease spread and increasing the incubation period of the virus in the plant. Casein was found effective in reducing the per cent transmission and increased the incubation ...


Effect Of Environmental Factors During Seed Development And Maturation On Seed Quality In Sorghum Bicolor (L.) Moench, Vilas A. Tonapi, S. Varanavasiappan, Shrishail S. Navi, Ch Ravinder Reddy, T. V. Karivatharaju Jan 2006

Effect Of Environmental Factors During Seed Development And Maturation On Seed Quality In Sorghum Bicolor (L.) Moench, Vilas A. Tonapi, S. Varanavasiappan, Shrishail S. Navi, Ch Ravinder Reddy, T. V. Karivatharaju

Plant Pathology and Microbiology Publications

Studies were conducted to evaluate the effect of environmental conditions on physiological characteristics of seeds of sorghum genotypes viz., CO 24, CO 25, CO 26 and JH 35 during seed development and maturation. In the present study, a steady decline in moisture content of the seed was observed. Length and width of seed increased rapidly between seven to 35 days after 50 per cent flowering. A steep increase in the dry weight of seed was registered between 14 and 35 days after 50 per cent flowering, beyond that the increase was gradual. Water absorption per cent declined from 16.5 ...


Studies On Seed Colouring In Soybean And Tomato, Vilas A. Tonapi, P. Harinath Babu, S. Varanavasiappan, Ch Ravinder Reddy, Shrishail S. Navi, N. Seetharama Jan 2006

Studies On Seed Colouring In Soybean And Tomato, Vilas A. Tonapi, P. Harinath Babu, S. Varanavasiappan, Ch Ravinder Reddy, Shrishail S. Navi, N. Seetharama

Plant Pathology and Microbiology Publications

The effects of seed colouring using 25 dyes (i.e. 20 chemical and 5 natural dyes) on the quality of soyabean (cv. JS 335) and tomato (cv. Pusa Ruby) seeds were studied in the laboratory. Data were recorded for seed germination percentage, root and shoot length, whole seedling length, dry weight of seedling, vigour index, speed of germination and electrical conductivity. Rhodamine-B, Fast green and Malachite green for soyabean and Rhodamine-B and Fast green for tomato were the best dyes for seed colouring.


Oscillating Kissing Stem-Loop Interactions Mediate 5′ Scanning-Dependent Translation By A Viral 3′-Cap-Independent Translation Element, Aurélie Mamisoa Rakotondrafara, Charlotta Polacek, Eva Harris, W. Allen Miller Jan 2006

Oscillating Kissing Stem-Loop Interactions Mediate 5′ Scanning-Dependent Translation By A Viral 3′-Cap-Independent Translation Element, Aurélie Mamisoa Rakotondrafara, Charlotta Polacek, Eva Harris, W. Allen Miller

Plant Pathology and Microbiology Publications

The 3′-untranslated regions (UTRs) of a group of novel uncapped viral RNAs allow efficient translation initiation at the 5′-proximal AUG. A well-characterized model is the Barley yellow dwarf virus class of cap-independent translation elements (BTE). It facilitates translation by forming kissing stem-loops between the BTE in the 3′-UTR and a BTE-complementary loop in the 5′-UTR. Here we investigate the mechanisms of the long-distance interaction and ribosome entry on the RNA. Upstream AUGs or 5′-extensions of the 5′-UTR inhibit translation, indicating that, unlike internal ribosome entry sites in many viral RNAs, the BTE relies on ...


Light Is Essential For Degradation Of Ribulose-1,5-Bisphosphate Carboxylase-Oxygenase Large Subunit During Sudden Death Syndrome Development In Soybean, J. Ji, M. P. Scott, M. K. Bhattacharyya Jan 2006

Light Is Essential For Degradation Of Ribulose-1,5-Bisphosphate Carboxylase-Oxygenase Large Subunit During Sudden Death Syndrome Development In Soybean, J. Ji, M. P. Scott, M. K. Bhattacharyya

Agronomy Publications

Fusarium solani f. sp. glycines (Fsg) has been reported to produce at least two phytotoxins. Cell-free Fsg culture filtrates containing phytotoxins have been shown to develop foliar sudden death syndrome (SDS) in soybean. We have investigated the changes in protein profiles of diseased leaves caused by cell-free Fsg culture filtrates prepared from Fsg isolates. Two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) was conducted to investigate the protein profiles of diseased and healthy leaves. An approximately 55 kDa protein was found to be absent in diseased leaves. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometric analyses and a database search revealed that the ...


Breeding For Grain Amino Acid Composition In Maize, Audrey Darrigues, Kendall R. Lamkey, M. Paul Scott Jan 2006

Breeding For Grain Amino Acid Composition In Maize, Audrey Darrigues, Kendall R. Lamkey, M. Paul Scott

Agronomy Publications

Improving the amino acid balance of grain has been a long-standing objective of plant-breeding research. In this chapter, we review the history of maize breeding for improved amino acid balance. Following this, we present results of our experiments involving divergent selection for the levels of the amino acids tryptophan and methionine in random-mated populations.


Dehydrin-Like Proteins In Soybean Seeds In Response To Drought Stress During Seed Filling, N. H. Samarah, R. E. Mullen, S. R. Cianzio, P. Scott Jan 2006

Dehydrin-Like Proteins In Soybean Seeds In Response To Drought Stress During Seed Filling, N. H. Samarah, R. E. Mullen, S. R. Cianzio, P. Scott

Agronomy Publications

There is no information on accumulation of dehydrin proteins during seed development and maturation of soybean [Glycine max (L.) Merr.] in response to drought stress. Our objective was to study accumulation of dehydrin-like proteins in developing soybean seeds in response to drought stress. A greenhouse experiment and a field experiment were conducted. In the greenhouse experiment, three treatments were imposed on soybean plants after beginning of linear seed filling (R5): well-watered (WW), gradual stress (GS) imposed before severe stress, and sudden severe stress (SS). In the field treatments were irrigation (I) and nonirrigation (NI) (rainfed) conditions imposed from R ...