Zelalem Mersha

Dr. Zelalem Mersha

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 October 2021 in Plant Disease
Verified
Journal Article
Closed access
SCShilpi Chawla
Shilpi Chawla
RRReza A. Rafie
Reza A. Rafie
MLM. Likins
M. Likins
SRShuxin Ren
Shuxin Ren
Eunice NdegwaEunice Ndegwa
Eunice Ndegwa
ZMZelalem Mersha
Zelalem Mersha
Ginger (Zingiber officinale Roscoe) is one of the most widely consumed medicinal herb in the world, and the U.S. imports of ginger have risen in recent years because of its health benefits. Seed rh...

1 May 2020 in Plant Disease
Verified
Journal Article
Open access
ZMZelalem Mersha
Zelalem Mersha
MKMaru K. Kering
Maru K. Kering
SRShuxin Ren
Shuxin Ren
Hemp (Cannabis sativa L.) is an annual herb from Cannabaceae family grown for its multitude of uses including fiber, seed and/or oil, and for its psychoactive ingredients. In August 2019, a hemp fa...

18 July 2024 in Agronomy
Verified
Journal Article
Open access
PDF file
ASAndualem S Shiferaw
Andualem S Shiferaw
GBGirma Birru
Girma Birru
Tsegaye TadesseTsegaye Tadesse
Tsegaye Tadesse
MSMarty R. Schmer
Marty R. Schmer
TATala Awada
Tala Awada
DDDagbegnon Clement Sohoulande Djebou
Dagbegnon Clement Sohoulande Djebou
Cover crops (CCs) offer ecosystem benefits, yet their impact on subsequent crop yields varies with climate, soil, and management practices. Using the Decision Support System for Agrotechnology Transfer (DSSAT) at the University of Nebraska-Lincoln’s Eastern Nebraska Research, Education, and Extension Center (ENREEC), we identified optimal cereal rye management strategies focusing on planting, termination, and the intervals between CC termination and corn planting. Results showed minimal impact of CC management variations on corn yield, underscoring corn’s resilience to management changes. Delayed planting notably decreased CC biomass, nitrogen uptake, and biomass nitrogen content on average by 8.8%, 11%, and 9.2% for every five-day delay from 25 September. Every 5-day increase in the interval between CC termination and corn planting reduced biomass by 19.3%. Conversely, each 5-day delay in CC termination from 10 September to 10 October increased biomass by 30%, enhancing SOC accumulation. SOC changes over the 30-year simulation ranged from 5.8% to 7.7%, peaking with late May terminations. The earliest termination showed the highest nitrogen content in biomass (3.4%), with the lowest (0.69%) in mid-May. Our results demonstrate that strategic CC management supports soil health without negatively impacting corn yield in Eastern Nebraska, providing valuable insights for farmers and practitioners aiming to implement sustainable CC practices while preserving crop productivity.

26 August 2013 in Journal of Phytopathology
Verified
Journal Article
Closed access
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ZMZelalem Mersha
Zelalem Mersha
SZShouan Zhang
Shouan Zhang
BHBernhard Hau
Bernhard Hau

22 September 2022 in Horticulturae
Verified
Journal Article
Open access
PDF file
ZMZelalem Mersha
Zelalem Mersha
MIMichael A. Ibarra-Bautista
Michael A. Ibarra-Bautista
With its multifaceted health benefits, ginger is one of the commonly consumed dietary condiments with continued demand worldwide leading to more importation into countries such as the U.S. The rhizome of ginger, the seed-piece but also the edible portion, is highly vulnerable to pathogen infections causing seed-piece and soil-borne diseases (SSDs). Laboratory and high tunnel (HT) studies were conducted between 2018 and 2020 to evaluate the effect of soil and transplant drenches of selected biocontrol agents (BCAs) and chemicals. In vitro dual-culture tests revealed that the Trichoderma harzianum strain T-22 (Th-22) grew significantly faster than Fusarium oxysporum f.sp. zingiberi (Foz), the fungus causing yellows and rhizome rot in ginger. Th-22 grew more than three times faster than Foz within 3 days and engulfed the pathogen within 7 days when incubated at 30 °C. The bioproducts (RootShield® Plus, LifeGard®), an insecticide/nematicide (Vydate®) and disinfectant (10% Clorox) tested against Foz and any pre-existing pathogens in a HT significantly reduced severity of yellowing and rhizome rot when compared with the non-treated control. Yield was significantly higher for RootShield® Plus compared to the control in one of the trials. Spatially, declining ginger growth but an increased incidence of SSDs were observed as one walked from the door towards the back of the HT. Phospho-lipid fatty acid analysis showed better microbial activity on soils that received drenches of BCAs than on soils sampled pre-treatment.

1 April 2023 in The Plant Pathology Journal
Verified
Journal Article
Open access
PDF file
ZMZelalem Mersha
Zelalem Mersha
GBGirma Birru
Girma Birru
BHBernhard Hau
Bernhard Hau
The fungal pathogen Pseudocercospora fuligena, known to affect tomatoes in the tropics and subtropics, has been reported from temperate climates including the United States and Turkey in recent years. In this study, an isolate from fresh tomatoes and the disease it causes were characterized and infection mechanisms investigated. Macroscopically, both sides of tomato leaves show indistinct effuse patches but prolific production of fuliginous lesions is conspicuous on the abaxial side first but also on the adaxial side later on as infection progressed. Microscopically, fascicles of conidiophores (11-128 µm × 3.5-9 µm) arising from stromata and conidia with up to 12 septations were observed. Molecular characterization of the isolate revealed high homology (99.8%) to other P. fuligena isolated from tomatoes in Turkey. Out of the 10 media tested, P. fuligena grew significantly well and sporulated better on unsealed tomato oatmeal agar and carrot leaf decoction agar, both supplemented with CaCO3. Direct transfer of conidia from profusely sporulating lesions was the easiest and quickest method of isolation for in-vitro studies. Light and scanning electron microscopy on cleared and intact tomato leaves further confirmed stomatal penetration and egress as well as prevalence of primary and secondary infection hyphae. In situ, blocked stomatal aperture areas of 154, 401, and 2,043 µm2 were recorded at 7, 12, and 17 days after inoculation, respectively. With the recent expanded horizon of the pathosystem and its consequential impact, such studies will be useful for a proper diagnosis, identification and management of the disease on tomato worldwide.