Nicholas Mills, Professor

Closed (1) Effect of climate change and irrigation regime on the emergence of walnut husk fly

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

Walnut husk fly is considered a significant pest in California walnut orchards. It is an invasive pest with few natural enemies and of which surprisingly little is known. The main objectives of the WHF experiments will be to elucidate the climatic factors that influence seasonal emergence of walnut husk fly. One experiment will be focused on measuring the size, weight and emergence times of pupae from various walnut orchards within a 3-hour radius of Berkeley which have been kept in different soil moisture and chill time conditions. The second project with WHF will involve analyzing past data of WHF infestation and emergence and comparing those with climate records to determine influencing factors over multi-year periods.

The most pressing task this fall will be data entry and data anlysis. There is potential for the right person to with prior knowledge of coding and/or statistics with a strong desire to learn more to work in R and begin working with data from this project under my supervision. There is also potential for someone to work with mapping polygons on landscapes and land-use analysis in R.


Day-to-day supervisor for this project: Sara Emery, Ph.D. candidate

Qualifications: 1. PUNCTUALITY: Because these are timed experiments with sensitive colonies, students must be willing to work on a consistent schedule. This will not require you to arrive in lab at an exact minute, but you will need to be able to work within a certain block of time during specified days. 2. TEAM WORK: The ability to work with others is essential. If possible, students will be paired with another research assistant. This serves two purposes 1) tasks are less daunting with the help of another person and 2) students will double check their partner's work.

Weekly Hours: 6-9 hrs

Related website: http://nature.berkeley.edu/millslab/Research_Interests.html

Closed (2) Can induced plant defenses limit the abundance of an invasive insect?

Applications for Fall 2017 are now closed for this project.

The Light Brown Apple Moth (LBAM) is an invasive leafrolling moth from Australia that was first found in California in 2007. Worries over the effects of this invasive species on California agriculture have prompted research into its potential geographic range and biological control factors, such as natural insect parasitism and diseases. Over the past 10 years, LBAM has experienced a decline that is unusual for an invasive species, a decline which is not fully explained by parasitism and disease. This project examines a new potential limiting factor for LBAM; induced plant defenses. Plants respond to insect herbivory by increasing defensive chemicals such as iridoid glycosides and tannins. To investigate the possible effects of induced plant defenses on the life history performance of LBAM, we are running cage experiments. These involve adding varying levels of inducing larvae to plants, allowing them to feed, then allowing a single bioassay larva to feed on leaves taken from the induced plants to determine if higher damage levels are associated with lower larval weight gain in the bioassay larvae. We are also doing field sampling of known LBAM populations around the Bay Area, which includes counts and collections for parasitism analysis.

Running an experiment requires maintaining a colony of LBAM. The colony must be maintained in a healthy state to provide experimental individuals for the fall and spring experimental season, as specific larval instars are necessary for accurate bioassay performance.

Colony maintenance tasks include:
1) Cutting eggs from oviposition cups
2) Picking LBAM pupae from diet cups
3) Making LBAM diet/honey
4) Maintaining various greenhouse plants for colonies/experiments

Other tasks include:
1)Data entry
2)Vial sanitizing

In addition, there may be some work recording emergences from field collected LBAM populations, depending on how many hours a week is needed for colony maintenance.

Day-to-day supervisor for this project: Katherine Patterson, Staff Researcher

Qualifications: Anyone interested in working in an insect biology lab is welcome to apply. The project involves working with insects, which are living organisms and therefore require timely maintenance. Punctuality, precision, and patience are essential.

Weekly Hours: to be negotiated

Related website: http://nature.berkeley.edu/millslab/Research_Interests.html