Agricultural Science Commons^™

Loss Of Comt Activity Reduces Lateral Root Formation And Alters The Response To Water Limitation In Sorghum Brown Midrib (Bmr) 12 Mutant, Manny Saluja, Feiyu Zhu, Hongfeng Yu, Harkamal Walia, Scott E. Sattler

Department of Agronomy and Horticulture: Faculty Publications

Lignin is a key target for modifying lignocellulosic biomass for efficient biofuel production. Brown midrib 12 (bmr12) encodes the sorghum caffeic acid O-methyltransferase (COMT) and is one of the key enzymes in monolignol biosynthesis. Loss of function mutations in COMT reduces syringyl (S) lignin subunits and improves biofuel conversion rate. Although lignin plays an important role in maintaining cell wall integrity of xylem vessels, physiological and molecular consequences due to loss of COMT on root growth and adaptation to water deficit remain unexplored.

We addressed this gap by evaluating the root morphology, anatomy and transcriptome of bmr12 mutant. The mutant …

Improving Publicly Available Corn Nitrogen Rate Recommendation Tools With Soil And Weather Measurements, Curtis J. Ransom, Newell R. Kitchen, John E. Sawyer, James J. Camberato, Paul R. Carter, Richard Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A.M. Laboski, D. Brenton Myers, Emerson D. Nafziger, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Improving corn (Zea mays L.) N fertilizer rate recommendation tools is necessary for improving farmers’ profits and minimizing N pollution. Research has repeatedly shown that weather and soil factors influence available N and crop N need. Adjusting available corn N recommendation tools with soil and weather measurements could improve farmers’ ability to manage N. The aim of this research was to improve publicly available N recommendation tools with site-specific soil and weather measurements. Information from49 site-years ofNresponse trials in theU.S. Midwest was used to evaluate 21 rate recommendation tools for a single (at-planting) and split (at-planting + sidedress) N …

Adaptation And Forage Productivity Of Cool-Season Grasses In The Central Usa, Kenneth P. Vogel, Robert B. Mitchell

Department of Agronomy and Horticulture: Faculty Publications

Cool-season grass species (18) and cultivars (85) were evaluated for use in seeded grasslands in the tallgrass prairie and shortgrass steppe ecoregions of the central United States at the test locations of Ithaca and Sidney, NE, respectively. Both native and introduced grasses were evaluated in sward trails. Significant differences existed among species and cultivars for all traits evaluated except for in vitro dry matter digestibility (IVDMD) among cultivars within species at Sidney. The grasses that had the best establishment, persistence, and forage yields in the Ithaca trial were introduced wheatgrass (Thinopyrum) and bromegrass (Bromus) species. At …

Identification And Utilization Of Genetic Determinants Of Trait Measurement Errors In Image-Based, High-Throughput Phenotyping, Yan Zhou, Aaron Kusmec, Seyed Vahid Mirnezami, Lakshmi Attigala, Srikant Srinivasan, Talukder Zaki Jubery, James Schnable, Maria G. Salas Fernandez, Baskar Ganapathysubramanian, Patrick S. Schnable

Department of Agronomy and Horticulture: Faculty Publications

The accuracy of trait measurements greatly affects the quality of genetic analyses. During automated phenotyping, trait measurement errors, i.e., differences between automatically extracted trait values and ground truth, are often treated as random effects that can be controlled by increasing population sizes and/or replication number. By contrast, there is some evidence that trait measurement errors may be partially under genetic control. Consistent with this hypothesis, we observed substantial non-random, genetic contributions to trait measurement errors for five maize (Zea mays) tassel traits collected using an image-based phenotyping platform. The phenotyping accuracy varied according to whether a tassel exhibited …

Evaluation Of Corn Agronomic Management Practices Following A Rye Cover Crop, Daniel John Quinn

Theses and Dissertations--Plant and Soil Sciences

Fall implementation of a rye (Secale cereale L.) cover crop (RCC) prior to spring corn (Zea mays L.) planting is a management practice used to improve soil conservation, water quality, and limit herbicide dependence. However, corn growth and yield following a RCC is often reduced due to early-season nitrogen (N) stress and decreased plant emergence, which can limit RCC adoption. The objective(s) of this research were to evaluate corn agronomic management practices (e.g., N and seeding rate management, in-furrow (IF) starter use) following a RCC and determine which management practices can be used to limit corn stress following …

Enhancing Agroecosystem Phosphorus Management: Root Phenotyping And Decomposition For Improved Phosphorus Cycling, Rebecca Kay Mcgrail

Theses and Dissertations--Plant and Soil Sciences

Plant roots are often overlooked when making nutrient management decisions. Evaluating differences in P acquisition strategies and cycling resulting from years of shoot-specific plant breeding will aid in reducing fertilizer inputs, with the ultimate goal of improving economic sustainability of crop production and preservation of ecosystem services. To achieve this goal, this research screened a diverse panel of winter wheat cultivars that included old and modern, dwarfed and wild type varieties for physical and chemical root phenotypes related to P acquisition. Old cultivars had larger root systems with more roots that grew two times faster than intermediate/modern cultivars. Wild type …

Soil Response Of Helicopter Liming In The Monongahela National Forest, Jarrett Douglas Fowler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Soils in the Monongahela National Forest (MNF) are acidic due to sandstone parent material, acid deposition, uptake of base cations by vegetation, and release of organic acids by organic matter (OM) decomposition. Increases in soil acidity have caused declines in forest health and changed species composition and nutrient status. Liming can neutralize soil acidity, but no large-scale liming projects have been done on acid forest soils in the USA. In anticipation of acquiring funding for a proposed liming project in the MNF, in 2007 and 2009 10 sites were selected to sample and analyze soils before lime was applied. In …

Black Soldier Fly Larval Meal In Feed Enhances Growth Performance, Carcass Yield And Meat Quality Of Finishing Pigs, S. Y. Chia, C. M. Tanga, I. M. Osuga, A. O. Alaru, D. M. Mwangi, M. Githinji, T. Dubois, S. Ekesi, J. J.A. Van Loon, M. Dicke

All Peer-Reviewed Publications

Using black soldier fly (BSF, Hermetia illucens) larvae as a novel protein source substituting fishmeal (FM) in animal feeds is globally gaining momentum. BSF can be reared on agro-industrial residues. However, incorporating BSF larval meal (BSFLM) into finisher pig diets has received inadequate attention. This study evaluated the effects of replacing dietary FM with BSFLM on growth, carcass traits and meat quality of finisher pigs. A control diet (including FM: 0% BSFLM) was compared with four dietary levels of replacement of FM with BSFLM at 25, 50, 75 or 100%. Forty hybrid pigs (crossbreeds of purebred Large White and Landrace) …

Effects Of Rhizobia And Arbuscular Mycorrhizal Fungi On Yield, Size Distribution And Fatty Acid Of Soybean Seeds Grown Under Drought Stress, Nicholas O. Igiehon, Olubukola O. Babalola, Xavier Cheseto, Baldwyn Torto

All Peer-Reviewed Publications

Soybean (Glycine max L.) is among the most economically important legumes that provide more than 1/4 of food (for man) and animal feed. However, its yield is comparatively low, most especially under drought stress. The aim of this study therefore was to assess the ability of Rhizobium spp. and mycorrhizal fungi to enhance the yield, seed size and fatty acid content of soybean grown under semi-arid environment. Rhizobium sp. strain R1 was found to possess nitrogen-fixing gene coniferyl aldehyde dehydrogenase function while Rhizobium cellulosilyticum strain R3 was found to have nitrogen-fixing genes cysteine desulfurase SufS and cysteine desulfurase IscS activity. …

Assessing And Understanding Non-Responsiveness Of Maize And Soybean To Fertilizer Applications In African Smallholder Farms, Dries Roobroeck, Cheryl A. Palm, Generose Nziguheba, Ray Weil, Bernard Vanlauwe

All Peer-Reviewed Publications

Use of mineral fertilizers is essential to enhance crop productivity in smallholder farming systems of Sub-Saharan Africa, but various studies have reported ‘non-responsiveness’ where application of inorganic fertilizers does not lead to satisfactory yield gains. This phenomenon is not well defined nor are its extent and causes well understood. In order to close these knowledge gaps, we assessed the effects of commonly recommended nitrogen (N), phosphorus (P) and/or potassium (K) fertilizer inputs on maize grain and soybean production on farmer fields across prevalent land slope and/or soil texture gradients (2 × 2 matrix) in four agroecosystems over two growing seasons. …

Low-Cost Technology For Recycling Agro-Industrial Waste Into Nutrient-Rich Organic Fertilizer Using Black Soldier Fly, Dennis Beesigamukama, Benson Mochoge, Nicholas K. Korir, Komi K.M. Fiaboe, Dorothy Nakimbugwe, Fathiya M. Khamis, Sevgan Subramanian, Musyoka M. Wangu, Thomas Dubois, Sunday Ekesi, Chrysantus M. Tanga

All Peer-Reviewed Publications

Efforts to recycle organic waste using black soldier fly (BSF) larvae into high-quality alternative protein ingredients in animal feeds and organic fertilizers have gained momentum worldwide. However, there is limited information on waste manipulation to increase nutrient retention for enhanced larval performance and frass fertilizer quality. In the present study, brewer's spent grain with a carbon to nitrogen (C/N) ratio of 11 (control) was amended with sawdust to obtain substrates with C/N ratios of 15, 20, 25 and 30. The effects of substrate C/N ratios on BSF larval yield, waste degradation, biomass conversion efficiency, compost maturity and nutrient levels of …

The Importance Of Store Hygiene For Reducing Post-Harvest Losses In Smallholder Farmers’ Stores: Evidence From A Maize-Based Farming System In Kenya, Kobia J. Makinya, John M. Wagacha, Judith A. Odhiambo, Paddy Likhayo, Kukom Edoh-Ognakossan, Tadele Tefera, Adebayo Abass, Christopher M. Mutungi

All Peer-Reviewed Publications

Knowledge of the role of hygiene in reducing food loss in farm stores is limited among extensionists, researchers, and farmers. Store hygiene practices during post-harvest handling and storage of maize were assessed using a cross-sectional survey of 342 farmers, with regular follow-up of 40 farmers’ stores over seven months to measure losses caused by insects, and to score the hygiene levels using a standard checklist. Fractional Response Model was used to evaluate the associations between hygiene practices and the losses. Farmers stored their produce in sacks (98.2%) kept in outside granaries (60.1%), or rooms in dwelling houses (39.9%). Co-storage with …

The Ethiopian Staple Food Crop Enset (Ensete Ventricosum) Assessed For The First Time For Resistance Against The Root-Lesion Nematode Pratylenchus Goodeyi, Selamawit A. Kidane, Beira H. Meressa, Solveig Haukeland, Anne Kathrine Hvoslef-Eide, Danny L. Coyne

All Peer-Reviewed Publications

Summary – Pratylenchus goodeyi appears to be the most prevalent nematode pest of enset in Ethiopia, where it can occur in extremely high densities. However, the damage to yield or how different enset cultivars react to the nematode has yet to be determined. The current study therefore sought to establish a first assessment of these reactions by enset to P. goodeyi infection. Determining pest-resistant cultivars is an important task in developing management strategies. Our study evaluated nine enset cultivars to establish host response and identify potential sources of resistance. In addition, the pathogenicity of P. goodeyi was assessed on three …