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Articles 11311 - 11340 of 14771

Full-Text Articles in Agricultural Science

Measuring The Influence Of Bedding On Soil Nitrogen Losses And Corn Crop Nitrogen Characteristics For Fall Applied Solid Beef Cattle Manure In Eastern South Dakota, Mukesh Mehata Jan 2018

Measuring The Influence Of Bedding On Soil Nitrogen Losses And Corn Crop Nitrogen Characteristics For Fall Applied Solid Beef Cattle Manure In Eastern South Dakota, Mukesh Mehata

Electronic Theses and Dissertations

Nitrogen (N) is a major component of chlorophyll which plays a key role in the photosynthesis process in crops. The N is one of the highest demanded nutrients by all plants for their growth and reproduction. Manure or inorganic fertilizer is often applied to fulfill the crops’ N demand. However, the applied N sources have the potential of N losses in different forms from the soil volume in many ways such as ammonia (NH3) volatilization, aerial nitrous oxide (N2O) loss, nitrate (NO3 --N) leaching, and runoff and/or erosion. Soil fertility, crop yield, water quality, and …


Cc-Type Glutaredoxins Mediate Plant Response And Signaling Under Nitrate Starvation In Arabidopsis, Ji-Yul Jung, Ji Hoon Ahn, Daniel P. Schachtman Jan 2018

Cc-Type Glutaredoxins Mediate Plant Response And Signaling Under Nitrate Starvation In Arabidopsis, Ji-Yul Jung, Ji Hoon Ahn, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Background: Nitrogen is an essential nutrient in plants. Despite the importance of nitrogen for plant growth and agricultural productivity, signal transduction pathways in response to nitrate starvation have not been fully elucidated in plants.

Results: Gene expression analysis and ectopic expression were used to discover that many CC-type glutaredoxins (ROXYs) are differentially expressed in response to nitrate deprivation. A gain-of-function approach showed that ROXYs may play a role in nutrient sensing through the regulation of chlorophyll content, root hair growth, and transcription of nitrate-related genes such as NRT2.1 under low or high nitrate conditions. Reactive oxygen species (ROS) …


Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza Jan 2018

Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza

Department of Agronomy and Horticulture: Faculty Publications

The anticipated world population growth emphasizes a need to produce more food on less land. Cutting-edge technologies, including genetic engineering, can help to develop improved crop varieties and protect natural resources. In spite of the potential for genetically-modified (GM) crops to make crop production more efficient, they remain a polarizing issue due to safety concerns. This paper provides an overview of the risk assessment process. The safety of Bacillus thuringiensis (Bt) proteins is used as an example for how risk assessment is applied to GM crops. Risks associated with GM crops have proven to be low to non-existent. Developing countries …


Impact Of Giant Miscanthus (Miscanthus X Giganteus) Cultivation On Midwestern Farmland Birds, Matthew Craffey Jan 2018

Impact Of Giant Miscanthus (Miscanthus X Giganteus) Cultivation On Midwestern Farmland Birds, Matthew Craffey

Masters Theses

Giant Miscanthus (Miscanthus x giganteus) is a promising bioenergy feedstock, newly introduced to North America. However, the qualities that make Giant Miscanthus an attractive bioenergy feedstock may pose challenges to local wildlife. To assess the impacts of Giant Miscanthus on Midwestern farmland birds, I conducted point count and vegetation surveys at three sites in east-central Illinois where Giant Miscanthus was being cultivated. I used occupancy modeling to assess the relative influence of Giant Miscanthus on five species relative to other habitat and landscape characteristics. Dickcissel (Spiza Americana), Eastern Meadowlark (Sturnella magna), and Red-Winged Blackbird …


An Assessment Of Effectiveness Of Participatory Video And Drama In Enhancing Learning Of “Climate-Smart” Push-Pull Technology: A Case Study Of Butere And Vihiga Farmers In Western Kenya, Wakesho George, Pittchar Jimmy, Midega Charles, Khan Zeyaur Jan 2018

An Assessment Of Effectiveness Of Participatory Video And Drama In Enhancing Learning Of “Climate-Smart” Push-Pull Technology: A Case Study Of Butere And Vihiga Farmers In Western Kenya, Wakesho George, Pittchar Jimmy, Midega Charles, Khan Zeyaur

All Peer-Reviewed Publications

This study assessed the effectiveness of participatory video and drama in enhancing learning of climate-smart pushpull technology in western Kenya. A total of 80 farmers who had no knowledge of push pull technology were exposed to participatory drama and video that had been developed by farmers who are adopting push pull technology. Validated questionnaires were used for data collection where sampled non push pull farmers were interviewed before and after exposure to push pull knowledge using participatory video and drama. Data obtained was analyzed using chi square at 0.05 confidence level set a priori and also presented using frequency tables, …


Relationship Between New Farming Practices And Chemical Use And The Consumption Of Giant Cricket (Brachytrupes Membranaceus Drury, 1770), F. O. Miantsia, F. Meutchieye, S. Niassy Jan 2018

Relationship Between New Farming Practices And Chemical Use And The Consumption Of Giant Cricket (Brachytrupes Membranaceus Drury, 1770), F. O. Miantsia, F. Meutchieye, S. Niassy

All Peer-Reviewed Publications

The current work is aimed at generating information on giant crickets and the impact of commonly used pesticides on the natural population of these crickets. Data was collected based on interviews and complemented with field observations. Out of 319 respondents surveyed, 290 were aware of the use of the giant cricket as a food source, and 161 were active consumers. Regarding the availability of the giant cricket, respondents reported that the crickets' populations were diminishing because of farming practices. About 219 persons reported that commonly used herbicides harm giant crickets at different stages. This could be attributed to the scarcity …


Push-Pull Farming System Controls Fall Armyworm: Lessons From Africa, Zeyaur R. Khan, Jimmy O. Pittchar, Charles A.O. Midega, John A. Pickett Jan 2018

Push-Pull Farming System Controls Fall Armyworm: Lessons From Africa, Zeyaur R. Khan, Jimmy O. Pittchar, Charles A.O. Midega, John A. Pickett

All Peer-Reviewed Publications

Fall armyworm (FAW) Spodoptera frugiperda invaded Africa, with the first detections being reported in Central and Western Africa in early 2016, and now affects at least 40 countries in Africa, causing up to total crop loss amounting to over $6.2 billion p.a. FAW is an invasive polyphagous pest that causes damage to economically important crops and has recently been reported in the Indian sub-continent. Effective control of FAW through use of synthetic chemical pesticides and genetically modified crops such as Bt maize faces challenges including improper use, unaffordability by smallholder farmers and development of resistance by the pest. Additionally, dispersal …


Farmers’ Perception And Control Practices Against The Invasive Red Spider Mite (Tetranychus Evansi Baker & Pritchard) In Benin, G. Y. Azandémè-Hounmalon, H. D. Affognon, F. Assogba-Komlan, M. Tamò, K. K.M. Fiaboe, S. Kreiter, T. Martin Jan 2018

Farmers’ Perception And Control Practices Against The Invasive Red Spider Mite (Tetranychus Evansi Baker & Pritchard) In Benin, G. Y. Azandémè-Hounmalon, H. D. Affognon, F. Assogba-Komlan, M. Tamò, K. K.M. Fiaboe, S. Kreiter, T. Martin

All Peer-Reviewed Publications

Tetranychus evansi (Acari: Tetranychidae), is an important pest of solanaceous plants in Benin where it damages tomato (Solanum lycopersicum L.; Solanaceae), African eggplant (S. macrocarpon L.; Solanaceae), purple amaranth (Amaranthus cruentus L.; Amaranthaceae). The objective of the present study was to evaluate the intensity of T. evansi damage and impact of farmers’ control practices in Benin. Two surveys were conducted between 2013 and 2016. The first survey revealed Tetranychus evansi as the only mite, causing production losses of 65% for African eggplant, 56% for tomato and 25% for purple amaranth. To protect the infested crops, growers sprayed various synthetic pesticides …


Lepidopteran Stem Borer Species Abundance And Associated Damages On Irrigated Kilombero Low Land Rice Ecosystem In Tanzania, Bonaventure January, Gration M. Rwegasira, Tadele Tefera Jan 2018

Lepidopteran Stem Borer Species Abundance And Associated Damages On Irrigated Kilombero Low Land Rice Ecosystem In Tanzania, Bonaventure January, Gration M. Rwegasira, Tadele Tefera

All Peer-Reviewed Publications

Background: Rice stem borers are among the most biotic stresses of economic importance in agriculture. Little was known about stem borer problem in Tanzania prior to this study. Understanding stem borer abundance and damages would help to design appropriate stem borer integrated pest management strategy in rice. This study was aimed at investigating rice stem borer’s species abundance and their associated damages in irrigated lowland rice ecosystem in Kilombero Tanzania. Materials and Methods: Field survey study on rice stem borer abundance and incidences were conducted in farmer’s fields on selected rice varieties at varied growth stages in Kilombero district under …


Respons Tiga Klon Tanaman Rami (Boehmeria Nivea (L.) Gaud) Terhadap Konsentrasi Asam Giberelat Yang Berbeda, Cucu Suherman, Anne Nuraini, Veronika Sri Rahayu Wulandari Dec 2017

Respons Tiga Klon Tanaman Rami (Boehmeria Nivea (L.) Gaud) Terhadap Konsentrasi Asam Giberelat Yang Berbeda, Cucu Suherman, Anne Nuraini, Veronika Sri Rahayu Wulandari

Jurnal Kultivasi

Tanaman rami merupakan salah satu jenis tanaman perkebunan penghasil serat yang serat-nya dapat dimanfaatkan dalam industri tekstil. Penelitian ini bertujuan untuk mengetahui pengaruh interaksi zat pengatur tumbuh asam giberelat (GA3) dan tiga klon rami terhadap pertumbuhan dan hasil tanaman rami serta mengetahui interaksi konsentrasi asam giberelat dan klon rami yang paling baik. Percobaan dilakukan di Kebun Percobaan Ciparanje, Fakultas Pertanian, Universitas Padjadjaran, Kabupaten Sumedang, ordo tanah Inceptisol, waktu pelaksanaan bulan Februari 2017 sampai bulan April 2017. Tipe curah hujan C (agak basah) menurut klasifikasi Schmidt dan Fergusson, dengan ketinggian tempat 754 mdpl. Percobaan ini menggunakan Rancangan Acak Kelompok pola Faktorial …


Hasil Benih Empat Kultivar Kedelai Yang Ditanam Di Dataran Medium Dan Dataran Tinggi, Sumadi, Muhamad Kadapi, Anne Nuraini, Noladhi Wicaksana, Meddy Rachmadi, S Rodiah Dec 2017

Hasil Benih Empat Kultivar Kedelai Yang Ditanam Di Dataran Medium Dan Dataran Tinggi, Sumadi, Muhamad Kadapi, Anne Nuraini, Noladhi Wicaksana, Meddy Rachmadi, S Rodiah

Jurnal Kultivasi

Pertumbuhan dan hasil suatu tanaman merupakan hasil interaksi antara karakter genetik setiap kultivar dengan lingkungan tumbuhnya. Tujuan penelitian ini adalah menetapkan kultivar kedelai yang paling cocok ditanam pada musim hujan di dataran medium ( ± 753 m dpl) dan dataran tinggi ( ± 1200 m dpl). Penelitian merupakan percobaan lapangan dilaksanakan pada April sampai dengan Juli 2016. Percobaan dirancang dalam Rancangan Acak Kelompok sederhana yang menguji kultivar meliputi Anjasmoro, Argomulyo, Arjasari dan Grobogan yang diulang 5 (lima) kali. Hasil percobaan menunjukkan bahwa secara umum potensi hasil kedelai di dataran medium hasilnya lebih tingggi dibandingkan yang ditanam di dataran tinggi. Kultivar …


Aplikasi Chitosan Untuk Meningkatkan Hasil Benih Kentang G0 (Solanum Tuberosum L.) Kultivar Granola Pada Berbagai Jenis Media Tanam, Anne Nuraini, Jajang Sauman Hamdani, Erni Suminar, Dian Ardiansyah Dec 2017

Aplikasi Chitosan Untuk Meningkatkan Hasil Benih Kentang G0 (Solanum Tuberosum L.) Kultivar Granola Pada Berbagai Jenis Media Tanam, Anne Nuraini, Jajang Sauman Hamdani, Erni Suminar, Dian Ardiansyah

Jurnal Kultivasi

Salah satu kendala dalam produksi kentang di Indonesia adalah rendahnya mutu benih yang digunakan. Untuk mengatasi hal tersebut penyediaan benih kentang dilakukan dengan kultur jaringan, dengan menghasilkan benih Go. Percobaan ini bertujuan untuk mengetahui efek aplikasi chitosan terhadap hasil benih kentang G0 kultivar Granola pada berbagain jenis media tanam. Percobaan dilaksanakan dari Februari 2012 sampai Mei 2012 di screen house Kebun Percobaan Ciparanje Faperta UNPAD, Jatinangor, dengan ketinggian tempat ±750 m dpl. Percobaan memakai Rancangan Petak Terbagi dengan tiga ulangan. Petak utama adalah komposisi media tanam terdiri dari empat taraf, yaitu tanah + sekam, tanah + sekam + pupuk kotoran …


Respon Pertumbuhan Dan Hasil Panen Rebung Periode Pertama Lima Kultivar Asparagus Pada Berbagai Konsentrasi Larutan Garam, Zalora Sanchenia, Tino Mutiarawati Onggo, Wawan Sutari Dec 2017

Respon Pertumbuhan Dan Hasil Panen Rebung Periode Pertama Lima Kultivar Asparagus Pada Berbagai Konsentrasi Larutan Garam, Zalora Sanchenia, Tino Mutiarawati Onggo, Wawan Sutari

Jurnal Kultivasi

Rebung asparagus (Asparagus officionalis L.) termasuk salah satu sayuran yang bernilai ekonomi tinggi di dunia juga di Indonesia. Kultivar asparagus yang ditanam di Indonesia umumnya merupakan kultivar introduksi dari daerah subtropis, sehingga pertumbuhan dan produksinya di Indonesia kurang optimal. Indonesia memiliki suhu dan kelembaban yang cukup tinggi sehingga dapat menyebabkan serangan berbagai penyakit pada tanaman asparagus. Aplikasi larutan garam pada media tanam mampu mengendalikan penyakit akar sehingga asparagus akan tumbuh dengan baik. Percobaan bertujuan mengetahui pengaruh konsentrasi larutan garam dan kultivar asparagus yang cocok untuk dataran medium Jatinangor supaya diperoleh pertumbuhan dan hasil rebung asparagus yang baik. Percobaan dilaksanakan di …


Respon Beberapa Klon Bibit Kina (Chinchona Sp) Asal Setek Sambung Dua Spesies Di Berbagai Media Tanam, Yudithia Maxiselly, Ahmad Shohibboniawan, Wawan Sutari, Noladhi Wicaksana, Heri Syahrian Khomaeni Dec 2017

Respon Beberapa Klon Bibit Kina (Chinchona Sp) Asal Setek Sambung Dua Spesies Di Berbagai Media Tanam, Yudithia Maxiselly, Ahmad Shohibboniawan, Wawan Sutari, Noladhi Wicaksana, Heri Syahrian Khomaeni

Jurnal Kultivasi

Kina merupakan tanaman yang selama ini dimanfaatkan sebagai obat berbagai penyakit, seperti malaria dan jantung karena memiliki kandungan alkaloid yang beragam. Peningkatan produktifitas tanaman kina dibutuhkan untuk menunjang kuantitas dan kualitas obat bahan alam. Salah satu factor penting dalam kualitas tanaman kina adalah bahan tanam yang baik. Bahan tanam juga didukung dengan kecocokan media tanam. Media tanam yang selama ini digunakan pada pembibitan kina memiliki kendala di bobot media sehingga sulit untuk pendistribusian bibit. Penelitian ini bertujuan mencari media baru yang cocok untuk bahan tanam kina. Bahan tanam menggunakan 6 klon kina succi yang disambung dengan 1 jenis kina ledger …


Multiplikasi Tunas Mikro Pisang (Musa Paradisiaca L.) ‘Raja Bulu’ Secara In Vitro Pada Berbagai Jenis Dan Konsentrasi Sitokinin, Tiara Elma, Erni Suminar, Syariful Mubarok, Anne Nuraini Dec 2017

Multiplikasi Tunas Mikro Pisang (Musa Paradisiaca L.) ‘Raja Bulu’ Secara In Vitro Pada Berbagai Jenis Dan Konsentrasi Sitokinin, Tiara Elma, Erni Suminar, Syariful Mubarok, Anne Nuraini

Jurnal Kultivasi

Terbatasnya ketersediaan bibit pisang bermutu di Indonesia disebabkan oleh masih rendahnya jumlah dan kualitas bibit pisang yang dihasilkan melalui metode konvensional. Waktu yang dibutuhkan untuk mendapatkan bibit cukup lama, oleh karena itu digunakan suatu metode perbanyakan untuk menghasilkan bibit dalam waktu yang relatif singkat melalui metode kultur jaringan. Tujuan dari penelitian ini adalah untuk mendapatkan salah satu jenis dan konsentrasi sitokinin terbaik dalam meningkatkan laju multiplikasi tunas pisang raja bulu secara in vitro. Percobaan dilaksanakan dari bulan November 2016 sampai bulan Maret 2017 di Laboratorium Kultur Jaringan dan Teknologi Benih Fakultas Pertanian Universitas Padjadjaran di Jatinangor, Sumedang. Rancangan Acak Lengkap …


Identifikasi Keragaman Genetik Plasma Nutfah Ubi Kayu Liar (Manihot Glaziovii Muell) Berdasarkan Karakter Morfo-Agronomi, Agung Karuniawan, Hendi N. Wicaksono, Debby Ustari, Tia Setiawati, T Supriatun Dec 2017

Identifikasi Keragaman Genetik Plasma Nutfah Ubi Kayu Liar (Manihot Glaziovii Muell) Berdasarkan Karakter Morfo-Agronomi, Agung Karuniawan, Hendi N. Wicaksono, Debby Ustari, Tia Setiawati, T Supriatun

Jurnal Kultivasi

Plasma nutfah tanaman merupakan sumber bahan genetik bagi program pemuliaan tanaman. Penelitian ini bertujuan untuk mengidentifikasi keragaman genetik plasma nutfah ubi kayu liar berdasarkan karakter morpho-agronomy. Percobaan dilaksanakan pada bulan Desember 2014 hingga Juni 2015. Rancangan percobaan menggunakan Rancangan Acak Kelompok (RAK) dengan perlakuan 23 aksesi ubi kayu liar dan diulang sebanyak dua kali. Analisis komponen utama menghasilkan biplot dengan nilai PC1 dan PC2 yang memiliki kontribusi terbesar terhadap variasi yaitu masing-masing sebesar 27.98% dan 19.45%. Analisis klaster menghasilkan gambar dendogram terdiri dari dua klaster utama yaitu I dan II. Pada gambar dendogram terdapat jarak euclidean antara 0.00 hingga 3.32. …


Pembentukan Ubi Mikro Kentang (Solanum Tuberosum L.) Pada Berbagai Komposisi Media In Vitro, Inneke Amalia, Anne Nuraini, Sumadi, Syariful Mubarok, Erni Suminar Dec 2017

Pembentukan Ubi Mikro Kentang (Solanum Tuberosum L.) Pada Berbagai Komposisi Media In Vitro, Inneke Amalia, Anne Nuraini, Sumadi, Syariful Mubarok, Erni Suminar

Jurnal Kultivasi

Permasalahan umum terkait pada produksi kentang adalah penggunaan benih sumber yang kurang bermutu dan mengalami kemunduran benih. Penelitian bertujuan untuk menentukan zat penghambat tumbuh coumarin, jasmonic acid dan paklobutrazol yang tepat untuk pertumbuhan stek dan pembentukan ubi mikro kentang secara in vitrosehingga dapat digunakan untuk penyediaan bibit berkualitas. Percobaan dilaksanakan di Laboratorium Kultur Jaringan Teknologi Benih Fakultas Pertanian Universitas Padjadjaran Jatinangor, Sumedang, pada bulan Oktober 2015 sampai Mei 2016. Metode percobaan yang digunakan adalah Rancangan Acak Lengkap (RAL) yang merupakan kombinasi dari media, retardan coumarin (105 mg L-1 dan 120 mg L-1), paklobutrazol (0.4 mg L-1 dan 1 mg L-1) …


Respon Pertumbuhan Bibit Nilam Aceh (Pogostemon Cablin Benth.) Klon Sidikalang Pada Media Tanam Subsoil Dengan Pemberian Pati Beras Dan Pupuk Hayati, Mira Ariyanti, Cucu Suherman, Intan Ratna Dewi Anjarsari, Dewi Santika Dec 2017

Respon Pertumbuhan Bibit Nilam Aceh (Pogostemon Cablin Benth.) Klon Sidikalang Pada Media Tanam Subsoil Dengan Pemberian Pati Beras Dan Pupuk Hayati, Mira Ariyanti, Cucu Suherman, Intan Ratna Dewi Anjarsari, Dewi Santika

Jurnal Kultivasi

Media tanam berupa topsoil masih menjadi andalan untuk mendukung pertumbuhan tanaman nilam karena kandungan mineral dan bahan organiknya yang tinggi. Seiring dengan pemanfaatannya, ketersediaan topsoil semakin berkurang dan dirasa perlu untuk mencari alternatif lain yaitu dengan memanfaatkan subsoil. Peningkatan unsur hara dalam subsoil dilakukan dengan cara pemberian pupuk organik berupa pati beras dan pupuk hayati. Percobaan dilakukan di Kebun Percobaan Fakultas Pertanian Universitas Padjadjaran Jatinangor pada Juni 2011- September 2011. Penelitian menggunakan rancangan acak kelompok terdiri dari 11 kombinasi perlakuan diulang tiga kali. Perlakuan percobaan meliputi top soil, sub soil + pupuk anorganik N 1.75 g, sub soil + 25 …


Arkansas Soybean Performance Tests 2017, R. D. Bond, J. A. Still, D. G. Dombek Dec 2017

Arkansas Soybean Performance Tests 2017, R. D. Bond, J. A. Still, D. G. Dombek

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.


In The Field The Women Saved The Crop: The Women’S Land Army Of World War Ii, Denna M. Clymer Dec 2017

In The Field The Women Saved The Crop: The Women’S Land Army Of World War Ii, Denna M. Clymer

Graduate Theses and Dissertations

The Women’s Land Army brought together rural and urban sectors of the United States in a climate of national and regional crisis. By the time the country was cast into war, the agricultural sector was already caught in a downward economic spiral that drove away laborers. With demand falling, and farms propped up only by experiments in subsidy and parity, when military and industrial jobs emerged in urban areas, farm laborers became scarce. At the same time the war created jobs for men outside of the agricultural sector, farm prices recovered and demand soared, forcing farmers to look to women …


New Technologies For Evaluating Putting Green Surface Characteristics, Daniel Patrick O'Brien Dec 2017

New Technologies For Evaluating Putting Green Surface Characteristics, Daniel Patrick O'Brien

Graduate Theses and Dissertations

Golf course putting greens require a high level of inputs predicated on timely, well informed decisions. Putting green quality is ultimately defined by performance of the turfgrass, and this performance encompasses both (i) the health and vitality of the turfgrass plants, and (ii) the ability of the turfgrass to exist as a playing surface, as it interacts with the golf ball. For golf course superintendents, accurately and efficiently assessing moisture levels and nutrient status are critical for guiding maintenance practices. This research sought to examine new ways for measuring each of these parameters, and compared them to ground-truth data and/or …


Evaluation Of Insecticide Seed Treatments To Protect Rice (Oryza Sativa) Against Various Herbicides, Steven Michael Martin Dec 2017

Evaluation Of Insecticide Seed Treatments To Protect Rice (Oryza Sativa) Against Various Herbicides, Steven Michael Martin

Graduate Theses and Dissertations

The increase in herbicide-resistant weeds in Arkansas crop fields has led to the need for new herbicide modes of action for use in all crops. This need has led to the introduction of technologies that can be devastating to conventional rice crops. Field observation, noted that insecticide seed treatments used in rice could potentially reduce the effects of off-target movement of herbicides onto rice crops and possibly reduce the negative effects of some herbicides applied directly to rice. Research was conducted to determine if insecticide seed treatments could reduce the harmful effects of drift from imazethapyr and glyphosate onto conventional …


Strong Spatial-Temporal Patterns In Maize Yield Response To Nutrient Additions In African Smallholder Farms, Samuel Njoroge, Antonius G.T. Schut, Ken E. Giller, Shamie Zingore Dec 2017

Strong Spatial-Temporal Patterns In Maize Yield Response To Nutrient Additions In African Smallholder Farms, Samuel Njoroge, Antonius G.T. Schut, Ken E. Giller, Shamie Zingore

All Peer-Reviewed Publications

Large variability in crop responses to macronutrient application at various spatial scales present challenges for developing effective fertilizer recommendations for crop production in smallholder farming systems of sub-Saharan Africa. We assessed maize yield responses to nitrogen (N), phosphorus (P) and potassium (K) application and evaluated relationships between crop responses to N, P and K application and soil analysis data. Nutrient omission trials were conducted on 23 farms located in Sidindi, Western Kenya, selected to be representative of the main soil and management factors in maize based systems in Siaya County. Treatments included a control and PK, NK, NP and NPK …


Identification Of Kairomones Of Second Instar Nymphs Of The Variegated Coffee Bug Antestiopsis Thunbergii (Heteroptera: Pentatomidae), Teresiah N. Njihia, Baldwyn Torto, Lucy K. Murungi, Janet Irungu, Dickson M. Mwenda, Régis Babin Dec 2017

Identification Of Kairomones Of Second Instar Nymphs Of The Variegated Coffee Bug Antestiopsis Thunbergii (Heteroptera: Pentatomidae), Teresiah N. Njihia, Baldwyn Torto, Lucy K. Murungi, Janet Irungu, Dickson M. Mwenda, Régis Babin

All Peer-Reviewed Publications

The variegated coffee bug Antestiopsis thunbergii Gmelin is a key pest of Coffea arabica in East Africa. Although the bug feeds on various parts of the coffee plant, it has a strong preference for mature green berries which are essential for the bug to complete its life cycle, reproduce and enhance its longevity. To locate mature green coffee berries, we hypothesized that second instar nymphs, which are the most mobile and active feeding immature stage of the bug, must rely on key volatile compounds emitted by the host for recognition. We tested this hypothesis using behavioral and electrophysiological assays and …


Welwitschianalol A And B, Two Cyclohexene Derivatives And Other Insecticidal Constituents Of Caesalpinia Welwitschiana (Oliv.) Brenan, Flaure Rosette Ehawa Essoung, Brice Mittérant Mba'ning, Wilber Lwande, Silvère Augustin Ngouela, Etienne Tsamo, Sumesh Chander Chhabra, Ahmed Hassanali, Russell John Cox Dec 2017

Welwitschianalol A And B, Two Cyclohexene Derivatives And Other Insecticidal Constituents Of Caesalpinia Welwitschiana (Oliv.) Brenan, Flaure Rosette Ehawa Essoung, Brice Mittérant Mba'ning, Wilber Lwande, Silvère Augustin Ngouela, Etienne Tsamo, Sumesh Chander Chhabra, Ahmed Hassanali, Russell John Cox

All Peer-Reviewed Publications

Crude methanol extract of the leaves of Caesalpinia welwitschiana was found to possess moderate larvicidal activity against second-instar larvae of Tuta absoluta Meyrick. Bioassay-guided fractionation of this extract led to the isolation of two oxygenated cyclohexene derivatives, welwitschianalol A (1, (1α,2β)-2-acetoxy-1-hydroxy-1- benzoyloxymethylcyclohex-5-ene) and B (2, (1α,2β)-2- benzoyloxy −1-cinnamoyloxymethyl-1-hydroxycyclohex-5-ene), together with eight known compounds, comprising bonducellin, dipteryxic acid, 3′-hydroxygenkwarin, afzelin, quercitrin, myricitrin, methyl gallate and gallic acid. The structures of the unknown compounds as well as those of the known ones were elucidated based on their MS, 1D and 2D NMR spectra, and in the case of known compounds, by comparison …


The Cotesia Sesamiae Story: Insight Into Host-Range Evolution In A Hymenoptera Parasitoid And Implication For Its Use In Biological Control Programs, L. Kaiser, S. Dupas, A. Branca, E. A. Herniou, C. W. Clarke, C. Capdevielle Dulac, J. Obonyo, R. Benoist, J. Gauthier, P. A. Calatayud, J. F. Silvain, B. P. Le Ru Dec 2017

The Cotesia Sesamiae Story: Insight Into Host-Range Evolution In A Hymenoptera Parasitoid And Implication For Its Use In Biological Control Programs, L. Kaiser, S. Dupas, A. Branca, E. A. Herniou, C. W. Clarke, C. Capdevielle Dulac, J. Obonyo, R. Benoist, J. Gauthier, P. A. Calatayud, J. F. Silvain, B. P. Le Ru

All Peer-Reviewed Publications

This review covers nearly 20 years of studies on the ecology, physiology and genetics of the Hymenoptera Cotesia sesamiae, an African parasitoid of Lepidoptera that reduces populations of common maize borers in East and South Africa. The first part of the review presents studies based on sampling of C. sesamiae from maize crops in Kenya. From this agrosystem including one host plant and three main host borer species, studies revealed two genetically differentiated populations of C. sesamiae species adapted to their local host community, and showed that their differentiation involved the joint evolution of virulence genes and sensory mechanisms of …


Predicting Minimum Tillage Adoption Among Smallholder Farmers Using Micro-Level And Policy Variables, Paswel P. Marenya, Menale Kassie, Moti Jaleta, Dil Bahadur Rahut, Olaf Erenstein Dec 2017

Predicting Minimum Tillage Adoption Among Smallholder Farmers Using Micro-Level And Policy Variables, Paswel P. Marenya, Menale Kassie, Moti Jaleta, Dil Bahadur Rahut, Olaf Erenstein

All Peer-Reviewed Publications

Minimum tillage combined with mulching (MTM) is critical to conservation agriculture, yet its use by smallholder farmers raises challenging questions regarding adoption, diffusion and scaling at farm level. In this paper, we used probit regression and post-estimation simulations to identify the key micro (farm specific) and macro (country specific) factors as predictors of MTM adoption in four countries spanning a north-south gradient in eastern and southern Africa (ESA): Ethiopia, Kenya, Tanzania and Malawi. We found that farmers’ access to markets and social capital empirically predicted MTM adoption. Policies that increased fertilizer subsidies and extension-staff-to-farmer ratios had similar effects, even if …


Parasitic Nematode Meloidogyne Incognita Interactions With Different Capsicum Annum Cultivars Reveal The Chemical Constituents Modulating Root Herbivory, Ruth Kihika, Lucy K. Murungi, Danny Coyne, Margaret Ng'ang'a, Ahmed Hassanali, Peter E.A. Teal, Baldwyn Torto Dec 2017

Parasitic Nematode Meloidogyne Incognita Interactions With Different Capsicum Annum Cultivars Reveal The Chemical Constituents Modulating Root Herbivory, Ruth Kihika, Lucy K. Murungi, Danny Coyne, Margaret Ng'ang'a, Ahmed Hassanali, Peter E.A. Teal, Baldwyn Torto

All Peer-Reviewed Publications

Plant volatile signatures are often used as cues by herbivores to locate their preferred hosts. Here, we report on the volatile organic compounds used by the subterranean root-knot nematode (RKN) Meloidogyne incognita for host location. We compared responses of infective second stage juveniles (J2s) to root volatiles of three cultivars and one accession of the solanaceous plant, Capsicum annum against moist sand in dual choice assays. J2s were more attracted to the three cultivars than to the accession, relative to controls. GC/MS analysis of the volatiles identified common constituents in each plant, five of which were identified as α-pinene, limonene, …


Evaluating The Impact Of Two Contrasting Tillage Practices On Soil Properties In Central Kentucky, Emily Cook Nov 2017

Evaluating The Impact Of Two Contrasting Tillage Practices On Soil Properties In Central Kentucky, Emily Cook

Posters-at-the-Capitol

Farming practices such as no tillage and plowing can institute change on soil physical and chemical characteristics. In this research, the effects of long-term conventional and no-tillage systems on the selected soil properties were determined in a continuous corn system on a farm with Maury silt loam soil. These samples were taken from University of Kentucky's Research Farm (Spindletop Farm). The field used was tilled in 1969 from bluegrass sod and the first time research was conduced was in 1970. Each plot is 20 ft. by 40 ft. and for many years each plot was split with winter cover crop …


Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda Nov 2017

Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda

LSU Master's Theses

Aspergillus flavus is a saprophytic ascomycete that can also actively invade the seed of crops and potentially contaminate them with harmful aflatoxins. Management of A. flavus currently relies mostly on biocontrol. However, there is still a lot to learn about its biology and ecology so the current approach can be improved. An A. flavus population survey was undertaken during the fall of 2014 across eight Mississippi River states to determine population diversity and geographic distribution of VCGs. Isolates from corn and soil were also characterized for VCG, sclerotial morphotype, mating type, cyclopiazonic acid, and aflatoxin production in order to determine …