Evaluating the Influence of Floral Resource Provisioning On

Biodiversity and Ecosystem Services in Agriculture: Evaluating the Influence of Floral Resource Provisioning on Biological Control of Erythroneura Leafhoppers (Hemiptera: Cicadellidae) and Planococcus Mealybug (Hemiptera: Pseudococcidae) in California Vineyards

Albie Felix Miles

A dissertation submitted in partial satisfaction of the

requirements for the degree of

Doctor of Philosophy

Environmental Science, Policy and Management

in the Graduate Division of the

University of California, Berkeley

Committee in charge:

Professor Miguel A. Altieri, Chair Professor John Hurst Dr. Kent M. Daane

Fall 2013

Abstract

Albie Felix Miles, Doctor of Philosophy in Environmental Science Policy and Management University of California, Berkeley

Professor Miguel A. Altieri, Chair

The global intensification of viticulture has led to the creation of monocultures characterized by an absence of non-crop vegetation in and around vineyards. The increased concentration of crop host resources, and the loss of non-crop habitats that support arthropod natural enemies can lead to increase pest pressure and crop loss. To manage recurring pest problems, many producers rely on synthetic insecticides posing a range of environmental quality and human health risks.

With increasing concern over the environmental impacts of viticulture, rising production costs, and increased regulation of pesticides, the demand for effective ecologically based pest management strategies has grown. Grape producers have sought to use ecologically based pest management strategies, including floral resource provisioning, to promote biological control of key vineyard pest. Despite growing interest, few ecologically based pest management strategies have been scientifically evaluated for the ability to consistently regulate pest populations or to clarify the underlying biology of control mechanisms when successful.

The research tested the natural enemies hypothesis in an attempt to explain why lower pest densities are observed in some diversified farming systems. The research evaluated the influence of floral resource provisioning (FRP) and chemical ecology strategies on biological control of Erythroneura leafhoppers (Hemiptera: Cicadellidae) and Planococcus mealybug (Hemiptera: Pseudococcidae) in California vineyards. Field and laboratory studies quantified the impacts on crop damage, pest and natural enemy abundance, and natural enemies fitness theorized to be enhanced through floral resource provisioning in agroecosystems. Multiple two-year studies measured the impact of intercropping three flowering ground covers, lacy phacelia (Phacelia tanacetifolia), bishop’s weed (Ammi majus), and common carrot (Daucus carota) on biological control of leafhoppers and vine mealybug by the parasitoids Anagrus spp. (Hymenoptera: Mymaridae) and Anagyrus pseudococci (Hymenoptera: Encyrtidae). Using identical intercropping treatments, the research included three large scale and fully replicated research designs located in the central San Joaquin, the northern San Joaquin, and the Napa Valley of California. Laboratory studies quantified the impacts of FRP on the fitness of Anagyrus pseudococci, a key parasitoid natural enemy of vine mealybug. The central San Joaquin Valley 1 field study measured the impact of FRP and pheromone based mating disruption on biological control of vine mealybug. The northern San Joaquin Valley field study measured the impact of FRP and methyl salicylate on b