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ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » People » Melissa Johnson

Melissa Anne Johnson

Research Biologist


Contact Information

USDA-ARS

Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center
64 Nowelo St.
Hilo, Hawaii 96720 
Ph: (808) 932-2118
Fx: (808) 959-5470 

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Publications

 Via ARIS

 Via ResearchGate

 Via Google Scholar

 

Education

Ph.D. in Botany, Claremont Graduate University, Claremont, CA, December 2016                                   

M.Sc. in Tropical Conservation Biology and Environmental Science, University of Hawaii at Hilo, May 2011

B.A. in Ecology, Evolution, and Conservation Biology, University of Hawaii at Hilo, May 2008

 

Research Positions

Research Projects and Accomplishments

 

 Area-wide Integrated Pest Management for Coffee Berry Borer

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Coffee berry borer (CBB, Hypothenemus hampei Ferrari) is the most damaging insect pest of coffee worldwide, causing more than $500 M in annual losses. CBB was first detected in Hawaii in 2010, and quickly spread to all coffee-producing regions in the islands. In 2016, we initiated area-wide monitoring of this pest at 14 commercial coffee farms on Hawaii Island, gathering information on coffee plant phenology, CBB flight activity, berry infestation, mortality by Beauveria bassiana, management practices and weather. Through this research we have accomplished a number of objectives to improve IPM for this global pest of coffee, including: 1) producing a scientific monitoring protocol for CBB that can be used by researchers worldwide to standardize data collection and enhance our ability to conduct comparative studies, 2) uncovering the role of feral, unmanaged and poorly managed coffee in the cycle of CBB infestation, 3) describing post-harvest reservoirs of CBB that result in infestation of the new season’s crop, 4) characterizing the seasonal phenology and influence of weather variables on CBB flight activity, 5) correlating CBB infestation with coffee plant phenology and providing insight into successful combinations of management practices, 6) describing CBB development times under natural field conditions, and 7) testing novel and sustainable methods of CBB control (e.g., exclusion netting, ground cover crops).

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Coffee Leaf Rust Monitoring

Detecteabs plot2d in late 2020 in Hawaii, Coffee Leaf Rust (CLR, Hemileia vastatrix) is a fungal pathogen that causes reduced photosynthesis and leaf drop, followed by subsequent losses in coffee production. CLR is described as the most devastating disease of coffee worldwide, resulting in 70% crop loss in some countries. In December 2020, we initiated CLR surveys across Hawaii Island to track the spread of the disease across the region, while collecting vital information on disease incidence and severity, as well as weather and farm management. This early response will provide critical information on disease biology and the factors that promote its dispersal and survival across a highly variable landscape. Together, this data will serve as the foundation for the development of an IPM strategy for this disease.

 

Evolution, Taxonomy, and Conservation of Pacific Island Plants

abs plot2Much of my earlier research has been centered on questions regarding the patterns and processes of speciation. Species are the fundamental units of biodiversity, yet we know relatively little about the processes that generate the amazing diversity of organisms across the planet. The oceanic islands of the Pacific provide an ideal setting for testing many biogeographic and evolutionary hypotheses regarding species diversification and were thus the focus of my graduate studies. Specifically, I sought to understand the mechanisms involved in the dispersal and diversification of plant species within and across island archipelagos. My methods combined detailed observations and experiments in field and greenhouse settings, molecular laboratory work to generate DNA sequence data and phylogenetic trees, tissue sectioning and scanning electron microscopy to compare anatomy and micromorphology, taxonomic study of preserved and field-collected specimens, and statistical models to determine the likelihood of evolutionary events. I have worked with several ecologically important Pacific plant genera in this capacity, inclabs plot2uding Metrosideros (Myrtaceae), Cyrtandra (Gesneriaceae), Clermontia (Campanulaceae) and Bidens (Asteraceae). Importantly, many species within these genera are extinct, endangered, or threatened, highlighting the importance of taxonomic and phylogenetic work to preserve these rare taxa. Through my extensive research on Cyrtandra I described five species new to science, all of which are considered endangered or critically endangered.

 

 

Service, Leadership and Participation in Professional Activities

 

Honors, Awards, Achievements and Recognition

           

Grant and Awards