Rodrigo Almeida, Professor

Open (1) Epidemiology of <i>Xylella fastidiosa</i> in grapevines

Open. Apprentices needed for the fall semester. Please do NOT contact faculty before September 11th (the start of the 4th week of classes)! Enter your application on the web beginning August 16th. The deadline to apply is Tuesday, August 29th at 8 AM.

<i>Xylella fastidiosa</i>, a bacterial plant pathogen, causes Pierce’s Disease in grapevines which costs vineyards over $100 million each year. We are investigating various dimensions of the epidemiology and ecology of <i>X. fastidiosa</i> to improve management of this important agricultural pathogen. First, we are investigating the role of an emerging insect vector species, the meadow spittlebug <i>Philaenus spumarius</i>, in recent epidemics in Napa and Sonoma county vineyards. Second, we are investigating the potential for hybrid grape varieties with novel resistance traits to reduce transmission of <i>X. fastidiosa</i> by vector insects, namely the blue-green sharpshooter <i>Graphocephala atropunctata</i>. Our work is highly diverse, including field work, greenhouse experiments, microbiology and molecular biology, and mathematical modeling. Students will learn quantitative PCR and bacterial culturing techniques for detection of <i>X. fastidiosa</i>, plant and insect care in the greenhouse, insect identification and morphology, and design and analysis of biological experiments and field studies. We also welcome student applicants interested in learning epidemic mathematical modeling.

Day-to-day supervisor for this project: Adam Zeilinger, Dylan Beal

Qualifications: Required: Ability to work as part of a team and independently. Desirable but not essential: Coursework, experience, and/or interest in epidemiology, ecology, vector biology, infectious diseases, plant pathology, or entomology.

Weekly Hours: 3-6 hrs

Related website: https://nature.berkeley.edu/almeidalab/research/

Open (2) Ecological genetics of an emerging insect vector

Open. Apprentices needed for the fall semester. Please do NOT contact faculty before September 11th (the start of the 4th week of classes)! Enter your application on the web beginning August 16th. The deadline to apply is Tuesday, August 29th at 8 AM.

The potato psyllid, <i>Bactericera cockerelli</i>, is the primary insect vector of an emerging plant pathogen, <i>Candidatus</i> Liberibacter solanacearum, that causes Zebra Chip disease in potatoes and tomatoes and has become an important management problem for growers in California, southwestern and northwestern US, Mexico, and Central America. While Zebra Chip disease and C. L. solanacearum were first discovered in the 1990s, the potato psyllid is native to western North America. We are investigating what has caused the emergence of Zebra Chip disease as an important plant pathogen. We have compiled a large set of museum specimens of the potato psyllid collected over the last century. By analyzing the distribution of these specimens and other related species over time, we found support for the hypothesis that potato psyllid populations have increased in California over the last century. This change in vector populations could help explain the emergence of Zebra Chip disease. As a next step, we are interested in analyzing genetic sequences for signatures of population change that may provide further support for this hypothesis. Students working on the project will learn PCR and other molecular biological techniques, bioinformatics, and ecological statistics. I also welcome student applicants interested in hierarchical statistical modeling.

Day-to-day supervisor for this project: Adam Zeilinger, Post-Doc

Qualifications: Required: Ability to work as part of a team and independently. Desirable but not essential: Coursework, experience, and/or interest in ecological genetics, molecular biology, infectious diseases, or ecological statistics.

Weekly Hours: 3-6 hrs

Related website: https://www.researchgate.net/publication/316602562_Museum_specimen_data_reveal_emergence_of_a_plant_disease_may_be_linked_to_increases_in_the_insect_vector_population

Closed (3) Looking for multipartite viruses

Closed. This professor is continuing with Spring 2017 apprentices on this project; no new apprentices needed for Fall 2017.

Multipartite viruses are viruses that have a fascinating genomic architecture since their genome is divided into 2 to 8 segments, each individually encapsidated. Among them, nanoviruses are the most extreme ones with a genome composed of 8 segments. These emerging viruses, which cause important damage on legume crops, have been reported in Europe and Africa but nobody has looked for them in America yet. The main goal of this project is thus to look whether these viruses are present in the U.S.A.





The student will learn common (thus very useful) techniques in microbiology such as DNA extraction, PCR, Elisa test, enzymatic restriction, gel electrophoresis as well as result interpretation. Besides, the student may participate in field trips to sample more leguminous plants and if so, the student will also learn how to identify plant species.

Day-to-day supervisor for this project: Anne Sicard, Post-Doc

Qualifications: Desirable but not essential: experience and/or interest in virology, plant pathology and/or microbiology.

Weekly Hours: 6-9 hrs

Related website: http://nature.berkeley.edu/~rodrigo/Lab%20page/index.html

Open (4) Determinants of Xylella fastidiosa host specificity

Open. Apprentices needed for the fall semester. Please do NOT contact faculty before September 11th (the start of the 4th week of classes)! Enter your application on the web beginning August 16th. The deadline to apply is Tuesday, August 29th at 8 AM.

Xylella fastidiosa is an emerging xylem-limited vector-borne bacterium associated with several important diseases in a wide range of plants including crops (e.g. grapevines, almonds, sweet orange, peach), ornamentals (e.g. oleander, hibiscus), and trees (e.g. oak, sycamore, elm). The species is capable of infecting over 300 plant species in 69 families; only few plant species tested have proved to be inadequate as hosts both under experimental conditions and in the field. However, for most host plant species, X. fastidiosa does not cause disease. Thus, colonization does not necessarily equal disease. Importantly, the minimal genomic diversity of X. fastidiosa available suggests different phylogenetic groups have similar pathogenicity mechanisms. Despite its importance as a plant pathogen, there are no hypotheses on the determinants of X. fastidiosa host specificity. This project aims to address this very important knowledge gap.

The student will learn how to do some DNA extraction, qPCR besides learning some techniques such as preparing bacterial media and culturing Xylella fastidiosa.

Day-to-day supervisor for this project: Anne Sicard, Post-Doc

Qualifications: Desirable but not essential: experience and/or interest in plant pathology and/or microbiology.

Weekly Hours: 6-9 hrs

Related website: http://nature.berkeley.edu/~rodrigo/Lab%20page/index.html