Agricultural Science Commons^™

Proteomic Profiling Of Maize Opaque Endosperm Mutants Reveals Selective Accumulation Of Lysine-Enriched Proteins, Kyla J. Morton, Shangang Jia, Chi Zhang, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Reduced prolamin (zein) accumulation and defective endoplasmic reticulum (ER) body formation occurs in maize opaque endosperm mutants opaque2 (o2), floury2 (fl2), defective endosperm*B30 (DeB30), and Mucronate (Mc), whereas other opaque mutants such as opaque1 (o1) and floury1 (fl1) are normal in these regards. This suggests that other factors contribute to kernel texture. A liquid chromatography approach coupled with tandem mass spectrometry (LC-MS/MS) proteomics was used to compare non-zein proteins of nearly isogenic opaque endosperm mutants. In total, 2762 proteins were identified that were enriched for biological processes such …

Impact Of Derived Global Weather Data On Simulated Crop Yields, Justin Van Wart, Patricio Grassini, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Crop simulation models can be used to estimate impact of current and future climates on crop yields and food security, but require long-term historical daily weather data to obtain robust simulations. In many regions where crops are grown, daily weather data are not available. Alternatively, gridded weather databases (GWD) with complete terrestrial coverage are available, typically derived from: (i) global circulation computer models; (ii) interpolated weather station data; or (iii) remotely sensed surface data from satellites. The present study’s objective is to evaluate capacity of GWDs to simulate crop yield potential (Yp) or water-limited yield potential (Yw), which can serve …

Irrigated Zea Mays Response To Nitrogen And High Plant Population Density In Narrow Rows, Julie Baniszewski

Theses and Dissertations--Plant and Soil Sciences

Modern genetics have improved maize hybrids to better tolerate stress, use nutrients more efficiently and potentially yield higher. Management practices, such as narrow row technology and high plant population density (PPD) may further improve yields in modern maize under irrigated, non-limiting conditions. High PPD (74, 99, 124, 148 K seeds ha^-1) were tested in narrow rows with up to four nitrogen (N) rates in three locations over two years in Kentucky with a modern maize hybrid in irrigated, non-limiting conditions. Results indicate that optimal seeding rates were 99,000 to 124,000 seeds ha^-1, providing maximum yield and …

Biochemical And Proteomic Profiling Of Maize Endosperm Texture And Protein Quality, Kyla J. Morton

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The research described herein, focuses on the biochemical and proteomic analysis of the maize endosperm and what influences kernel texture. Quality Protein Maize (QPM) is a hard endosperm version of the high-lysine opaque2 (o2) mutant but the genes involved in modifying the soft o2 endosperm are unknown. Pyrophosphate (PPi)-dependent fructose 6-phosphate 1-phosphotransferase (PFP) catalyzes the ATP-independent conversion of fructose 6-phosphate to fructose 1, 6-bisphosphate in glycolysis. We found a large increase in transcript and protein levels of the alpha regulatory subunit of PFP (PFPα) in QPM endosperm. In vitro enzyme assays show a significant increase in forward PFP …

Potential For Crop Production Increase In Argentina Through Closure Of Existing Yield Gaps, Fernando Aramburu Merlos, Juan Pablo Monzon, Jorge L. Mercau, Miguel Taboada, Fernando H. Andrade, Antonio J. Hall, Esteban Jobbagy, Kenneth Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Favorable climate and soils for rainfed crop production, together with a relatively low population density,results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78%of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale.The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across …

Proteomic Profiling Of Maize Opaque Endosperm Mutants Reveals Selective Accumulation Of Lysine-Enriched Proteins, Kyla J. Morton, Shangang Jia, Chi Zhang, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Reduced prolamin (zein) accumulation and defective endoplasmic reticulum (ER) body formation occurs in maize opaque endosperm mutants opaque2 (o2), floury2 (fl2), defective endosperm*B30 (DeB30), and Mucronate (Mc), whereas other opaque mutants such as opaque1 (o1) and floury1 (fl1) are normal in these regards. This suggests that other factors contribute to kernel texture. A liquid chromatography approach coupled with tandem mass spectrometry (LC-MS/MS) proteomics was used to compare non-zein proteins of nearly isogenic opaque endosperm mutants. In total, 2762 proteins were identified that were enriched for biological processes such as protein transport and folding, amino acid biosynthesis, …

How Do Various Maize Crop Models Vary In Their Responses To Climate Change Factors?, Simon Bassu, Nadine Brisson, Jean-Louis Durand, Kenneth J. Boote, Jon Lizaso, James Jones, Cynthia Rosenzweig, Alex Ruane, Myriam Adam, Christian Baron, Bruno Basso, Christian Biernath, Hendrick Boogaard, Sjaak Conijn, Marc Corbeels, Delphine Deryng, Giacomo De Sanctis, Sebastian Gayler, Patricio Grassini, Jerry Hatfield, Steven Hoek, Cesar Izaurralde, Raymond Jongschaap, Armen Kemanian, Christian Kersebaum, Soo-Hyung Kim, Naresh Kumar, David Makowski, Christoph Muller, Claas Nendel, Eckart Priesack, Maria Virinia Pravia, Federico Sau, Iurii Shcherbak, Fulu Tao, Edmar Teixeira, Dennis Timlin, Katharina Waha

Department of Agronomy and Horticulture: Faculty Publications

Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide …

Molecular Markers Reveal Narrow Genetic Base And Culturing-Associated Genetic Drift In Teretrius Nigrescens Lewis Populations Released For The Biological Control Of The Larger Grain Borer In Africa, B. A. Omondi, J. Van Den Berg, D. Masiga, F. Schulthess

All Peer-Reviewed Publications

In biological control, successful establishment of a natural enemy species depends on its adaptability in the introduced range including its ability to re-establish desired ecological interactions with the pest. These are affected by genetic parameters hitherto largely unresolved in biological control. The larger grain borer (LGB), Prostephanus truncatus, an invasive species from meso-America, is the most important post-harvest pest of maize in Africa. We studied the genetic structure of Teretrius nigrescens, a predatory beetle previously released for the control of the pest in Africa, to test the hypothesis that establishment patterns were a result of ecotype-environment mismatch and to follow …

Triple Bag Hermetic Storage Delivers A Lethal Punch To Prostephanus Truncatus (Horn) (Coleoptera: Bostrichidae) In Stored Maize, A. W. Njoroge, H. D. Affognon, C. M. Mutungi, J. Manono, P. O. Lamuka, L. L. Murdock

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Clean shelled maize was stored in woven polypropylene (PP) or triple layer polyethylene (PICS™) bags in the presence of Prostephanus truncatus Horn (PP1; PICS1) or absence of it (PP0; PICS0) at ambient conditions for six months. Moisture content, live insect population, grain damage, weight loss, and germination were analyzed on a monthly basis. Temperature and relative humidity in both PICS- and PP-bag setups were monitored, as well as the oxygen and carbon dioxide levels in the PICS bags. Overall, maize stored in PICS bags had significantly lower (P<0.05) moisture content than maize stored in PP bags. Storage in PICS bag slowed growth of P.truncatus populations and blocked infestation from the surrounding storage environment. On the contrary, PP bags permitted profuse build-up of insect population and cross-infestation. At six months, grain damage was 0.0%, 3.4%, 50.5% and 73.9%, corresponding to weight loss of 0.0%, 2.0%, 36.3%, and 47.7% in PICS0, PICS1, PP0 and PP1, respectively. Germination of maize stored in PP bags dropped from 91.1% to 37.0% and 12.7% in PP0 and PP1, respectively, whereas germination of maize stored in PICS bags dropped only marginally and reached 78.1% and 71.0% in PICS0 and PICS1, respectively, in six months. Without extreme loss of grain viability, a huge decrease in insect infestation, grain damage and weight loss is achieved by storing maize in PICS bag even under P.truncatus endemic conditions. © 2014 Elsevier Ltd.

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …

Agricultural Development In The Northern Savannah Of Ghana, Tara N. Wood

Doctor of Plant Health Program: Dissertations and Student Research

Since declaring independence in 1957, the Republic of Ghana has become a stable constitutional democracy. Ghana’s economy has grown substantially over the past decade, yet remains primarily agrarian, accounting for 50% of the total employment and 25% of the country’s Gross Domestic Product. Smallholder rain-fed farming using rudimentary technologies dominates the agricultural sector accounting for 80% of total agricultural production. Approximately 90% of smallholder farms are less than two hectares in size, and produce a diversity of crops. The major crops cultivated in Ghana include numerous cereal, root and tuber, leguminous, fruit, vegetable and industrial crops. Maize is the most …

Dark Green Color Index As A Method Of Real-Time In-Season Corn Nitrogen Measurement And Fertilization, Upton Siddons

Graduate Theses and Dissertations

Corn (Zea mays L.) requires higher rates of nitrogen fertilizer than any other major U.S. crop partly because N fertilizers are subject to loss through various mechanisms. Because of this, corn may suffer from inadequate nitrogen fertilization or producers may over-apply nitrogen to compensate for early-season nitrogen losses. A timely, accurate, and precise method for measuring in-season corn N status is needed to allow producers to keep nitrogen use efficiency high within a growing season.

Using appropriate software, hue, saturation, and brightness values of digital images can be combined in a dark green color index (DGCI) which is closely associated …

Effects Of Mulching, N-Fertilization And Intercropping With Desmodium Uncinatum On Striga Hermonthica Infestation In Maize, Charles A.O. Midega, Jimmy Pittchar, Daisy Salifu, John A. Pickett, Zeyaur R. Khan

All Peer-Reviewed Publications

The parasitic weed Striga hermonthica is a major constraint to maize production in sub-Saharan Africa and causes serious food insecurity. We discovered serendipitously an effective control method for the weed that involves intercropping cereals with the fodder legume, silverleaf desmodium, Desmodium uncinatum (Jacq.) DC., through mechanisms that involve soil shading and nitrogen fixation. In the current study we investigated long-term effects of inorganic nitrogen (N), mulching and D. uncinatum, singly and in combinations, on S. hermonthica infestation, maize plant growth and grain yields. Treatments comprised sole maize with and without 120 kg N/ha; sole maize plots covered with maize straw …

Arbuscular Mycorrhizal Fungi Differ In Their Ability To Regulate The Expression Of Phosphate Transporters In Maize (Zea Mays L.), Hui Tian, Rhae A. Drijber, Xiaolin Li, Daniel N. Miller, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Previous studies have found that some phosphate (Pi) starvation inducible transporter genes are downregulated and arbuscular mycorrhizal (AM) inducible Pi transporter genes are upregulated in maize roots associated with the fungus Glomus intraradices. However, little is known about the functional diversity of different AM fungal species in influencing the expression of Pi transporters in maize roots. Here, we studied the expression of two Pi transporter genes ZEAma:Pht1;3 (Pi starvation inducible) and ZEAma:Pht1;6 (AM inducible) in maize root colonized by different AM fungal inoculants. Non-mycorrhizal maize, maize colonized by Glomus deserticola (CA113), Glomus intraradices (IA506), Glomus mosseae (CA201), Gigaspora gigantea …

Estimating Crop Yield Potential At Regional To National Scales, Justin Van Wart, Kurt Christian Kersebaum, Shaobing Peng, Maribeth Milner, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

World population will increase 35% by 2050, which may require doubling crop yields on existing farm land to minimize expansion of agriculture into remaining rainforests, wetlands, and grasslands. Whether this is possible depends on closing the gap between yield potential (Yp, yield without pest, disease, nutrient or water stresses, or Yw under water-limited rainfed conditions) and current average farm yields in both developed and developing countries. Quantifying the yield gap is therefore essential to inform policies and prioritize research to achieve food security without environmental degradation. Previous attempts to estimate Yp and Yw at a global level have been too …

The Impact Of Desmodium Spp. And Cutting Regimes On The Agronomic And Economic Performance Of Desmodium-Maize Intercropping System In Western Kenya, M. Kifuko-Koech, P. Pypers, J. R. Okalebo, C. O. Othieno, Z. R. Khan, J. A. Pickett, A. K. Kipkoech, B. Vanlauwe

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Low soil fertility, stemborers (particularly, Chilo partellus) and Striga weeds (Striga hermonthica and Striga asiatica) are major limitations to production of maize in western Kenya. The " Push-Pull" technology ("PPT") has been described as an appropriate innovative technology capable of addressing these constraints. The technology involves intercropping maize with Desmodium and planting Napier grass (Pennisetum purpureum) around the intercrop, but in the current study a modified PPT was used and Napier grass was not included. Field trials were conducted in two locations in western Kenya during 4 subsequent seasons to test the hypothesis that maize yield, the degree of Striga …

Carbon Exchange By Establishing Biofuel Crops In Central Illinois, Marcelo Zeri, Kristina Anderson-Teixeira, George Hickman, Michael Masters, Evan Delucia, Carl J. Bernacchi

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

Perennial grass bio-fuels may contribute to long-term carbon sequestration in soils, thereby providing a broad range of environmental benefits. To quantify those benefits, the carbon balance was investigated over three perennial grass bio-fuel crops – miscanthus (Miscanthus×giganteus), switch-grass (Panicum virgatum) and a mixture of native prairie plants – and a row crop control (maize–maize–soy) in Central Illinois, USA, during the establishment phase of the perennial grasses (2008–2011). The eddy covariance technique was used to calculate fluxes of carbon dioxide and energy balance components, such as latent and sensible heat fluxes. Whereas maize attained the highest maximal …

Estimating Maize Grain Yield From Crop Biophysical Parameters Using Remote Sensing, Noemi Guindin-Garcia

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The overall objective of this investigation was to develop a robust technique to predict maize (Zea mays L.) grain yield that could be applied at a regional level using remote sensing with or without a simple crop growth simulation model. This study evaluated capabilities and limitations of the Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Index 250-m and MODIS surface reflectance 500-m products to track and retrieve information over maize fields. Results demonstrated the feasibility of using MODIS data to estimate maize green leaf area index (LAI_g). Estimates of maize LAI_g obtained from Wide Dynamic Range Vegetation …

Participatory Evaluation Of Integrated Pest And Soil Fertility Management Options Using Ordered Categorical Data Analysis, Hugo De Groote, Esther Rutto, George Odhiambo, Fred Kanampiu, Zeyaur Khan, Richard Coe, Bernard Vanlauwe

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Maize is becoming the major food crop around Lake Victoria. Major constraints to its production are Striga, stem borer, and declining soil fertility. Innovative integrated technologies have been developed: the 'push-pull' system (intercropping with Desmodium and surrounded by Napier grass), soybean and Crotalaria rotations, and imidazolinone-resistant (IR) maize seed. In 12 demonstration trials in four villages in Siaya and Vihiga districts (Kenya) and two villages in Busia (Uganda) in 2003 and 2004, 504 farmers evaluated all cropping systems and a mono-cropped continuous maize, each cropped with IR or local maize, and supplemented or not with fertilizer, totaling 16 treatments. Farmers …

Inoculation With Arbuscular Mycorrhizal Fungi Or Crop Rotation With Mycorrhizal Plants Improves The Growth Of Maize In Limed Acid Sulfate Soil, Hasao Higo, Katsunori Isobe, Dong-Jin Kang, Kazuhiro Ujie, Rhae A. Drijber, Ryuichi Ishii

Department of Agronomy and Horticulture: Faculty Publications

Arbuscular mycorrhizal fungi (AMF) improve the uptake of immobile mineral nutrients such as phosphate, thereby improving plant growth. In acid sulfate soil (ASS), AMF spore density is generally low which impacts root colonization and phosphate uptake. Thus, inoculation may help increase AMF colonization of crops grown in ASS. AMF spore density decreases after cultivation of a non-host crop or bare fallow. In addition, preceding crops affect the growth and yield of subsequent crops. The production of AMF inocula requires AMF-compatible plants. The objective of the present study is to elucidate the effect of preceding crops on the persistence of inoculated …

Integration Of Edible Beans (Phaseolus Vulgaris L.) Into The Push-Pull Technology Developed For Stemborer And Striga Control In Maize-Based Cropping Systems, Zeyaur R. Khan, Charles A.O. Midega, Japhether M. Wanyama, David M. Amudavi, Ahmed Hassanali, Jimmy Pittchar, John A. Pickett

All Peer-Reviewed Publications

Smallholder farming systems in eastern Africa are characterized by cereal/edible legume intercrops in fields severely constrained by parasitic weed, Striga hermonthica, cereal stemborers and declining soil fertility. The push-pull technology concurrently addresses these constraints. It involves intercropping maize with stemborer repellent fodder legume, Desmodium spp. (push), with an attractant crop, Napier grass, Pennisetum purpureum (pull), planted around this intercrop, thus making it difficult to interplant edible legumes. We assessed farmers' practice and perceptions on intercropping and willingness to integrate beans in their push-pull plots from a sample of 300 farmers in six districts in western Kenya. All the respondents traditionally …

Field Release Of A Non-Toxigenic Aspergillus Flavus L Strain In Central Benin, A. M. Klueken, C. Borgemeister, B. Hau

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Non-toxigenic strains of Aspergillus flavus (Link) can be used as biological control agents to reduce the contamination of grains such as maize with carcinogenic and immunotoxic aflatoxins. Based on its sclerotial morphology, A. flavus is commonly divided into two types: L strains and S strains. In this study, we applied the non-toxigenic A. flavus L strain BN030D to the soil of five maize fields in Djidja, central Benin, to investigate its effects on the composition of the prevailing fungal communities, on the ratio of A. flavus L strains and S strains, and on the vegetative compatibility of L strains with …

On-Farm Evaluation Of The 'Push-Pull' Technology For The Control Of Stemborers And Striga Weed On Maize In Western Kenya, Zeyaur R. Khan, Charles A.O. Midega, David M. Amudavi, Ahmed Hassanali, John A. Pickett

All Peer-Reviewed Publications

The 'push-pull' technology is a novel pest management strategy developed for control of stemborers and striga weed, Striga hermonthica, in maize-based farming systems in eastern Africa, where maize is intercropped with desmodium, a forage legume, and Napier grass is planted as a border crop. Desmodium repels stemborer moths while Napier grass attracts them. Desmodium also suppresses the parasitic striga weed through a series of mechanisms ranging from shading to allelopathy through the root system. The technology is currently being disseminated among smallholder farmers in eastern Africa and adoption rates are rising. Our on-station studies have reported efficacy of this technology …

Distribution And Relative Importance Of Lepidopteran Cereal Stemborers And Their Parasitoids In Uganda, T. Matama-Kauma, F. Schulthess, J. A. Ogwang, J. M. Mueke, C. O. Omwega

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Infestation levels and parasitism of lepidopteran stemborers on maize were assessed in four agroecological zones (AEZ) in Uganda. The indigenous noctuid Busseola fusca Fuller (Noctuidae) and the invasive Chilo partellus Swinhoe (Crambidae) were the most important stemborers recorded. C. partellus represented 77% of the stemborers in the Eastern AEZ while B. fusca was dominant in the other AEZs, accounting for 60-79%. The proportion of infested plants was between 16% and 45% and borer density between 0.2 and 1.0 borers per plant. There was no clear relationship between damage and stem tunneling, which is often used to estimate yield loss. Telenomus …

Farmers' Perceptions Of Importance, Control Practices And Alternative Hosts Of Maize Stemborers In Uganda, T. Kalule, Z. R. Khan, G. Bigirwa, J. Alupo, S. Okanya, J. A. Pickett, L. J. Wadhams

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A survey was conducted in Tororo, Bugiri and Kapchorwa districts in eastern and northeastern Uganda on farmers' perceptions of constraints in maize production. Farmers in Tororo and Bugiri consistently ranked stemborers and striga as the major production constraints in maize growing, while those in Kapchorwa ranked stemborers and lack of capital as the most important. Approximately 35 and 40% of the farmers in Tororo and Bugiri, respectively, identified stemborers as the 'caterpillar' that destroys their maize. In Kapchorwa, 50% of the farmers identified stemborers. Pesticide application was the most common control measure while the use of indigenous and cultural control …

Electrophysiological Responses Of The Lepidopterous Stemborers Chilo Partellus And Busseola Fusca To Volatiles From Wild And Cultivated Host Plants, M. A. Birkett, K. Chamberlain, Z. R. Khan, J. A. Pickett, T. Toshova, L. J. Wadhams, C. M. Woodcock

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The stemborers Chilo partellus and Busseola fusca are major pests of subsistence cereal farming in Africa. Volatiles released by two cultivated hosts, sorghum and maize (Sorghum bicolor and Zea mays), and two wild grass hosts, Pennisetum purpureum and Hyparrhenia tamba, were collected by air entrainment. Electrophysiologically active components in these samples were detected by coupled gas chromatography-electroantennography (GC-EAG), and the active peaks identified by gas chromatography-mass spectrometry. A total of 41 compounds were identified from the four plant species, all of which, as well as two unidentified compounds, elicited an electrophysiological response from one or both of the stemborers. The …

Combined Control Of Striga Hermonthica And Stemborers By Maize-Desmodium Spp. Intercrops, Zeyaur R. Khan, John A. Pickett, Lester J. Wadhams, Ahmed Hassanali, Charles A.O. Midega

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The African witchweed (Striga spp.) and lepidopteran stemborers are two major biotic constraints to the efficient production of maize in sub-Saharan Africa. Previous studies had shown the value of intercropping maize with Desmodium uncinatum in the control of both pests. The current study was conducted to assess the potential role of other Desmodium spp., adapted to different agro-ecologies, in combined control of both pests in Kenya. Treatments consisted of intercropped plots of a Striga hermonthica- and stemborer-susceptible maize variety and one Desmodium sp. or cowpea, with a maize monocrop plot included as a control. S. hermonthica counts and stemborer damage …

Diel Periodicity In The Production Of Green Leaf Volatiles By Wild And Cultivated Host Plants Of Stemborer Moths, Chilo Partellus And Busseola Fusca, K. Chamberlain, Z. R. Khan, J. A. Pickett, T. Toshova, L. J. Wadhams

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The volatile chemicals produced by four poaceous plant species, blue thatching grass, Hyparrhenia tamba, Napier grass, Pennisetum purpureum, sorghum, Sorghum bicolor, and maize, Zea mays, which are host plants for the lepidopterous stemborers, Chilo partellus and Busseola fusca, were collected by air entrainment and analyzed by gas chromatography. The total quantities of volatiles collected hourly, over a 9-hr period, from P. purpureum and H. tamba showed an approximately hundredfold increase in the first hour of the scotophase. Thereafter, the amount decreased rapidly to levels present during photophase. Although onset of scotophase also triggered an increase in quantities of volatiles collected …

International Shipping Of Fumonisins From Maize Extracts On C18 Sorbent, R. T. Riley, O. A. Torres, E. Palencia

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

Fumonisins are mycotoxins found in maize. In developing countries, the resources required for analysis are often lacking, and the shipping of maize between countries can be difficult since the importation of plant materials requires permits/ inspection to prevent the entry of pests that frequently infest maize. A simple, safe and legal method for shipping maize extracts to the USA was needed to conduct a survey of fumonisins in Central America. The objective was to develop a method for isolating and shipping maize extracts for fumonisin analysis so as to facilitate a survey of fumonisin exposure. The results indicate that fumonisins …

The Effect Of Nitrogen Fertilizer Application To Maize And Sorghum On The Bionomics Of Chilo Partellus (Lepidoptera: Crambidae) And The Performance Of Its Larval Parasitoid Cotesia Flavipes (Hymenoptera: Braconidae), N. Jiang, F. Schulthess

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Laboratory and field trials were conducted to evaluate the effect of plant species (maize, sorghum), plant age (young, middle, old) and four different nitrogen fertilization levels (N0-N3) on the bionomics of the invasive crambid Chilo partellus and the performance of its braconid larval parasitoid Cotesia flavipes. Plant N varied significantly between N0 and N1-N3, but the differences among the latter were not significant. Intrinsic rates of increase and net-reproductive rates of C. partellus followed the same trends: they were lowest with N0 and similar among the other treatments. On maize only, mortality of C. partellus and parasitism by C. flavipes …