Molecular Identification of Plant Pathogens Affecting Cannabis sativa Crops in Nevada

Cannabis sativa L. is an herbaceous flowering plant in the family Cannabaceae. C. sativa has emerged to be an important economic crop in the United States and is now widely cultivated as hemp for fiber, oil, and seed, and as marijuana (referred to henceforth as cannabis) for medicinal or recreational psychotropic purposes. In Nevada, hemp varieties are generally grown commercially in fields, while cannabis varieties are generally grown indoors. Both types of plants are susceptible to certain diseases, resulting in significant loss of crop yield. To understand hemp pathology and the major pathogens associated with diseases, we investigated the major diseases encountered by farmers and cultivators in Nevada in recent years. Each disease was systemically evaluated to determine the nature of its problem. In order to elucidate the etiology and accurately identify the pathogens that caused the observed diseases, morphological, pathological, and molecular approaches were used. This thesis emphasizes molecular approaches, i.e., DNA barcoding, to identify species based on rDNA sequences and analyzing viral capsid protein gene sequences, which enabled the successful identification of every encountered organism to a species level. The pathogens identified in this study include five Fusarium species: F. oxysporum, F. solani, F. equiseti, F. redolens, and F. tricinctum, two Alternaria species: A. infectoria and A. tennuisima, a powdery mildew fungus: Golovinomyces ambrosiae, a virus: Beet curly top virus, and a fastidious bacterium; 'Ca. Phyoplasma trifolii'. These organisms were found to be devastating pathogens of C. sativa crops, and they all were first detected from C. sativa crops in Nevada. Correctly identifying pathogens affecting C. sativa crops provides a foundation for the management of hemp and cannabis diseases and fills the gap of current information on C. sativa pathology.

Level thesis:degree_level

Master's Degree

Year dc:date.issued

2021

Author dc:creator

• Schoener, Jennifer

Advisors dc:contributor.advisor

• Kosma, Dylan
• Wang, Shouhua

Committee members dc:contributor.committeemember

• Kosma, Dylan
• Wang, Shouhua
• Solomon, Juan

• Cannabis sativa
• molecular detection
• plant pathogens

Statement dc:rights

• Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 United States

Handle dc:identifier.uri

http://hdl.handle.net/11714/7809

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/7809