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Agronomy and Crop Sciences Commons

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Articles 1 - 10 of 10

Full-Text Articles in Agronomy and Crop Sciences

Effective Control Of Tomato Leaf Miner, Tuta Absoluta (Meyrick) (Lepidoptera: Gelechiidae) Using The Entomopathogenic Fungus, Beauveria Pseudobassiana Rehner & Humber In Commercial High-Arched Plastic Tunnels, Aya Fardoun, Nour Ezzeddine, Hagop S. Atamian, Hana Sobh, Houssam Shaib, Yusuf Abou Jawdah Oct 2025

Effective Control Of Tomato Leaf Miner, Tuta Absoluta (Meyrick) (Lepidoptera: Gelechiidae) Using The Entomopathogenic Fungus, Beauveria Pseudobassiana Rehner & Humber In Commercial High-Arched Plastic Tunnels, Aya Fardoun, Nour Ezzeddine, Hagop S. Atamian, Hana Sobh, Houssam Shaib, Yusuf Abou Jawdah

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background

The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a highly invasive pest that causes significant damages to tomato crops globally. Its resistance to commonly used chemical insecticides has made management increasingly difficult, prompting the need for sustainable, effective alternatives. This study investigated the efficacy of a Lebanese isolate of Beauveria pseudobassiana as a biological control agent against T. absoluta, compared its performance to Bacillus thuringiensis and conventional pesticide mixtures under both controlled, commercial production conditions

Results

Three preliminary cage experiments were conducted under controlled infestation conditions using larvae reared from field-collected adults. Conidial suspensions of B. pseudobassiana …


Unraveling Crop Nitrogen-Water Dynamics With Hyperspectral-Thermal Sensing In Northern Central Valley, California, Shahryar Fazli, Surendra Maharjan, Wenzhao Li, Joshua B. Fisher, Rejoice Thomas, Fernando Romero Galvan, Gabriela Shirkey, Hesham El-Askary Sep 2025

Unraveling Crop Nitrogen-Water Dynamics With Hyperspectral-Thermal Sensing In Northern Central Valley, California, Shahryar Fazli, Surendra Maharjan, Wenzhao Li, Joshua B. Fisher, Rejoice Thomas, Fernando Romero Galvan, Gabriela Shirkey, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Ensuring global food security in the face of climate change requires optimizing crop water use and nutrient management. This study investigates the relationship between canopy nitrogen (N) and evapotranspiration (ET) across sunflower, rice, walnut, alfalfa, and plum crops using advanced remote sensing technologies. High-resolution hyperspectral data from NASAs Earth Surface Mineral Dust Source Investigation (EMIT) and thermal multispectral data from the Landsat-based OpenET system were analyzed over 1,135 km2 in California. Regression analysis revealed strong spatial association between canopy N and ET for sunflower (R2 = 0.82), rice (R2 = 0.71), and walnut (R2 = 0.68), …


How Advection Affects The Surface Energy Balance And Its Closure At An Irrigated Alfalfa Field, Tianxin Wang, Joseph Alfieri, Kanishka Mallick, Ariane Arias-Ortiz, Martha Anderson, Joshua B. Fisher, Manuela Girotto, Daphne Szutu, Joseph Verfaillie, Dennis Baldocchi Aug 2024

How Advection Affects The Surface Energy Balance And Its Closure At An Irrigated Alfalfa Field, Tianxin Wang, Joseph Alfieri, Kanishka Mallick, Ariane Arias-Ortiz, Martha Anderson, Joshua B. Fisher, Manuela Girotto, Daphne Szutu, Joseph Verfaillie, Dennis Baldocchi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Orbiting around the non-closure problem in eddy covariance, a new generation of high-resolution thermal imagery has revealed that advection may be more common than previously expected. To investigate this, we conducted an extensive study over an irrigated alfalfa field that experienced heat and moisture advection. Over the course of five analysis periods (37 days total), multiple tower arrays and profile measurements were deployed to measure the horizontal advection and vertical heat flux divergence. Latent heat flux (λE) measured at the anchor tower showed an enhancement (i.e., increase) due to both local and non-local processes. Locally, as a result of the …


Biological Control Of Three Major Cucumber And Pepper Pests: Whiteflies, Thrips, And Spider Mites, In High Plastic Tunnels Using Two Local Phytoseiid Mites, Yusuf Abou Jawdah, Nour Ezzedine, Aya Fardoun, Samer Kharroubi, Hana Sobh, Hagop S. Atamian, Margaret S. Skinner, Bruce Parker Mar 2024

Biological Control Of Three Major Cucumber And Pepper Pests: Whiteflies, Thrips, And Spider Mites, In High Plastic Tunnels Using Two Local Phytoseiid Mites, Yusuf Abou Jawdah, Nour Ezzedine, Aya Fardoun, Samer Kharroubi, Hana Sobh, Hagop S. Atamian, Margaret S. Skinner, Bruce Parker

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

To enhance food security, food safety, and environmental health, a bio-based integrated pest management (BIPM) strategy was evaluated at two coastal locations in Lebanon as an alternative to toxic pesticide sprays in commercial high-arched plastic tunnels common in many countries. The evaluation occurred during two cucumber and pepper cropping seasons: spring and fall. At each site, two commercial tunnels were used; farmers’ conventional practices were applied in one tunnel, while the BIPM approach was followed in the second tunnel. In the farmers’ practices, a total of 14 sprays of insecticide/acaricide mixtures were applied during the spring growing season, and 6 …


Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini, Sian Xiao, Mayar Terek Ibrahim, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao Mar 2024

Β-Sheets Mediate The Conformational Change And Allosteric Signal Transmission Between The Aslov2 Termini, Sian Xiao, Mayar Terek Ibrahim, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

Avena sativa phototropin 1 light-oxygen-voltage 2 domain (AsLOV2) is a model protein of Per-Arnt-Sim (PAS) superfamily, characterized by conformational changes in response to external environmental stimuli. This conformational change begins with the unfolding of the N-terminal A'α helix in the dark state followed by the unfolding of the C-terminal Jα helix. The light state is characterized by the unfolded termini and the subsequent modifications in hydrogen bond patterns. In this photoreceptor, β-sheets are identified as crucial components for mediating allosteric signal transmission between the two termini. Through combined experimental and computational investigations, the Hβ …


Extreme Development Of Dragon Fruit Agriculture With Nighttime Lighting In Southern Vietnam, Shenyue Jia, Son V. Nghiem, Seung-Hee Kim, Laura Krauser, Andrea E. Gaughan, Forest R. Stevens, Menas Kafatos, Khanh D. Ngo Mar 2022

Extreme Development Of Dragon Fruit Agriculture With Nighttime Lighting In Southern Vietnam, Shenyue Jia, Son V. Nghiem, Seung-Hee Kim, Laura Krauser, Andrea E. Gaughan, Forest R. Stevens, Menas Kafatos, Khanh D. Ngo

Institute for ECHO Faculty Books and Book Chapters

Dragon fruit is widely grown in Southeast Asia and other tropical or subtropical regions. As a high-value cash crop ideal for exportation, dragon fruit cultivation has boomed during the past decade in southern Vietnam. Light supplementing during the winter months using artificial lighting sources is a widely adopted cultivation technique to boost productivity in the major dragon fruit planting regions of Vietnam. The application of electric lighting at night leads to a significant increase of nighttime light (NTL) observable by satellite sensors. The strong seasonality signal of NTL in dragon fruit cultivation enables identifying dragon fruit plantations using NTL images. …


A Microbiome Engineering Framework To Evaluate Rhizobial Symbionts Of Legumes, Kenjiro W. Quides, Hagop S. Atamian Mar 2021

A Microbiome Engineering Framework To Evaluate Rhizobial Symbionts Of Legumes, Kenjiro W. Quides, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background

For well over a century, rhizobia have been recognized as effective biofertilizer options for legume crops. This has led to the widespread use of rhizobial inoculants in agricultural systems, but a recurring issue has emerged: applied rhizobia struggle to provide growth benefits to legume crops. This has largely been attributed to the presence of soil rhizobia and has been termed the ‘rhizobial competition problem.’

Scope

Microbiome engineering has emerged as a methodology to circumvent the rhizobial competition problem by creating legume microbiomes that do not require exogenous rhizobia. However, we highlight an alternative implementation of microbiome engineering that focuses …


Reporting Charcoal Rot In Chia And Developing A Susceptibility Assay, Reis M. Misaka, Hagop S. Atamian Dr., Julien Besnard Dr. May 2019

Reporting Charcoal Rot In Chia And Developing A Susceptibility Assay, Reis M. Misaka, Hagop S. Atamian Dr., Julien Besnard Dr.

Student Scholar Symposium Abstracts and Posters

Chia (Salvia Hispanica) cross breeds were planted in the summer of 2018 with the intent of selective breeding for agricultural benefit. Preexisting pathogens in the soil caused 40-50% fatality of adult plants. This was surprising due to the precursory knowledge that chia has antibiotic and antifungal oils (Elshafie et. al. 2018); chia was only recently documented to be susceptible to Fusarium wilt (Fusarium oxysporum). The primary pathogen responsible was identified as Macrophomina phaseolina (aka charcoal rot); a widespread soilborne pathogen which has multiple commercial hosts (Su et. al. 2001).

M. phaesolina on wheat seed vector where used as …


Sequence Analysis Of The Potato Aphid Macrosiphum Euphorbiae Transcriptome Identified Two New Viruses, Marcella A. Texeira, Noa Sela, Hagop S. Atamian, Ergude Bao, Rita Chaudhury, Jacob Macwilliams, Jiangman He, Sophie Mantelin, Thomas Girke, Isgouhi Kaloshian Mar 2018

Sequence Analysis Of The Potato Aphid Macrosiphum Euphorbiae Transcriptome Identified Two New Viruses, Marcella A. Texeira, Noa Sela, Hagop S. Atamian, Ergude Bao, Rita Chaudhury, Jacob Macwilliams, Jiangman He, Sophie Mantelin, Thomas Girke, Isgouhi Kaloshian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The potato aphid, Macrosiphum euphorbiae, is an important agricultural pest that causes economic losses to potato and tomato production. To establish the transcriptome for this aphid, RNA-Seq libraries constructed from aphids maintained on tomato plants were used in Illumina sequencing generating 52.6 million 75±105 bp paired-end reads. The reads were assembled using Velvet/Oases software with SEED preprocessing resulting in 22,137 contigs with an N50 value of 2,003bp. After removal of contigs from tomato host origin, 20,254 contigs were annotated using BLASTx searches against the non-redundant protein database from the National Center for Biotechnology Information (NCBI) as well as IntereProScan. …


Effect Of Phytosanitary Irradiation On The Quality Of Two Varieties Of Pummelos (Citrus Maxima (Burm.) Merr.), A. Jain, J. Ornelas-Paz, D. Obenland, K. Rodriguez (Friscia), Anuradha Prakash Jan 2017

Effect Of Phytosanitary Irradiation On The Quality Of Two Varieties Of Pummelos (Citrus Maxima (Burm.) Merr.), A. Jain, J. Ornelas-Paz, D. Obenland, K. Rodriguez (Friscia), Anuradha Prakash

Food Science Faculty Articles and Research

Phytosanitary treatments prevent the introduction of pests such as fruit flies into pest free zones, and are often required for international trade. Irradiation is increasingly being considered as an alternative to cold and chemical phytosanitary treatments, such as methyl bromide. In this study, the effect of low dose gamma irradiation on the post-harvest quality of two varieties of pummelos (Citrus maxima (Burm.) Merr.), an emerging crop of interest in the US was evaluated. Two varieties of pummelos grown in California were irradiated at the phytosanitary target dose of 150 Gy and a higher dose of 1000 Gy to exaggerate …