Overview of the Updated California Strawberry Pest Management Strategic Plan

Peter W. Shearer, Ph.D. and Gerald Holmes, Ph.D.Strawberry Center, Cal Poly University

Marla Livengood, Mercy Olmstead, Ph.D. and Dan Legard, Ph.D.California Strawberry Commission

Presentation outline

• Pest Management Strategic Plans• What are they?• Why are they important?

• Present information on CA strawberry• Overview of CA strawberry production• Overview of pest problems (diseases, arthropods and weeds)

• Highlight common research, regulatory and educational priorities between the current and previous 2003 CA strawberry PMSP• Provide overview of new priorities for CA Strawberry PMSP

Pest Management Strategic Plans (PMSP)

• PMSPs address pest management needs and priorities for individual commodities in a particular state or region. • The plans take a pest-by-pest approach to identifying the current management practices (chemical and nonchemical) and those under development.• They are developed by growers, commodity associations, land-grant university specialists, food processors, crop consultants, and the EPA. • Plans include priorities for research, regulatory activity, and education/training programs needed for transition to alternative pest management practices.

Benefits from completing a PMSP• Regulators receive information on actual pest management practices and therefore will be less likely to use default assumptions in risk assessments.• Regulators are provided information on important uses for special concerns (e.g., resistance management, geographical concerns).• Stakeholders identify appropriate contact people to facilitate future communication.• Growers have available documentation to support Section 18 Emergency Exemption and Section 24(c) Special Local Needs requests.

Benefits from completing a PMSP (cont.)• Commodity representatives get a document that can be used

to convey their needs to policy makers.• Support for IR-4 Food Use Workshop research prioritization is

provided.• Registrants may use PMSPs to identify niche markets for

development of new products.• PMSPs foster multi-state and multi-regional collaboration

resulting in less duplication of efforts and more judicious use of limited dollars.• Grant seekers acquire documentation of stakeholder priority

needs to support funding requests.

Other Strawberry PMSPs

• 2015: CT, MA, ME, NH, NY, RI, VT (Joint NE Region)

• 2007: FL

• 2003: TN

Since the 2003 PMSP, the California strawberry industry has increased the number of acres, reaching a peak in 2014 at 41,500 acres. Since then, acreage continues to decline, currently around 37,900 acres, while production remains stable because of the availability of high-yielding varieties.

2018 value of CA strawberry production $3.03 billion USD

• Farms in Orange County/San Diego and

Oxnard harvest fruit from January to May.

• Farms in Santa Maria and

Watsonville/Salinas harvest from March

through November.

• Central Valley, the summer planting

produces fruit that is harvested from April

– July. A fall crop is then harvested from

July – October.

• Oxnard and Santa Maria plant a summer

crop which is harvested from September to

December.

Characteristics of the Major Strawberry Production Areas in California in a Typical Season.

Oxnard/Ventura Santa Maria Watsonville/SalinasMain Cultivars

Fall Planted

Proprietary cultivars

(57.4%)

‘Fronteras’ (20%)

‘San Andreas’

(14.7%)

‘Monterey’ (43.7%)

‘San Andreas’ (22.8%)

Proprietary cultivars (17.3%)

Proprietary cultivars

(49.7%)

‘Monterey’ (39.7%)

‘Cabrillo’ (6.3%)

Summer Planted Proprietary cultivars

(86.4%)

‘Portola’ (13.4%)

‘Portola’ (55.3%)

Proprietary cultivars

(26.3%)

None

Acreage: Fall Planted 5,300

(190 organic)

8,583

(911 organic)

11,601

(2,011 organic)

Acreage: Summer

Planted

3,462

(292 organic)

2,528

(745 organic)

21

(21 organic)

(% is based on 2018 reported and estimated acreage)

California Pest Management Strategic Plan• Updating the 2003 CA Strawberry PMSP

• Meetings were held in July, 2016• Watsonville, Santa Maria and Oxnard/Ventura

• Additional input received in 2018• Intent is to have current PMSP available on-line this quarter

Major arthropod pests of strawberry

Twospotted spider mites

Whiteflies

Lygus bug and damage

Holmes UC IPM UC IPM

Major fruit and foliar diseases

Botrytis grey moldAnthracnose Powdery mildew

Cornell Holmes

Major soil-borne diseases

Fusarium wilt

S. Koike

Verticillium wilt Macrophomina Crown Rot

CA STRAWBERRY COM. Steven Koike, UCCE

Key pests per district

Key Pests Oxnard Santa Maria Watsonville/SalinasArthropods Twospotted spider

mites

Lygus

Twospotted spider mites

Whiteflies

Lygus

Twospotted spider mites

Lygus

Whiteflies

Foliar and Fruit Diseases

Powdery Mildew

Botrytis Anthracnose

Powdery Mildew

Botrytis

Botrytis

Powdery Mildew Anthracnose

SoilborneDiseases

MacrophominaCrown Rot

Fusarium Wilt

Macrophomina Crown Rot

Verticillium Wilt

Verticillium Wilt

Fusarium Wilt

Macrophomina Crown Rot

Annuals and Perennial Weeds of Significance to California Strawberry Production

Annuals: Perennials:• Annual bluegrass • Spotted spurge • Sweet clover • Cudweed • Hairy fleabane• Horseweed• Knotweed • Filaree• Little mallow

(cheeseweed) • Sowthistle• Common groundsel • California bur clover

• Field bindweed • Yellow nutsedge

Shearer

Insects, Diseases and Other Pests of Strawberry Effectively Controlled with Fumigant Applications

Insects Pathogens Nematodes Weeds

Root weevils, cutworms, strawberry rootworm, white grubs, garden symphylan, ground mealybug

Verticillium dahliae, Phytophthora spp., Fusarium oxysporum f. sp. fragariae, Macrophominaphaseolina(charcoal rot),

Colletotrichumacutatum, Pythium spp, Rhizoctonia

Root knot, foliar

All, except certain perennials and broadleaves; does not control malva, clovers, filaree, oxalis, or bindweed

CA Strawberry PMSP: 2003 & 2018 overlapping research priorities

• Find alternatives to methyl bromide.• Develop new methods to produce clean nursery stock. • Conduct (continue) long-term research on alternatives to fumigants in production fields.• Develop resistance management strategies for lygusand spider mites.• Evaluate new materials and techniques to manage arthropods. • Develop and evaluate herbicides for under plastic .

CA Strawberry PMSP: Additional 2018 research priorities• Develop new cultivars which are resistant to insects, nematodes and diseases.• Conduct research on soil amendments to improve microbial community to encourage “suppressive” soil development.• Conduct research on alternative weed management strategies.

CA Strawberry PMSP: 2003 & 2018 overlapping regulatory priorities• Register alternatives to methyl bromide. • Register new products for arthropods and powdery mildew. Register more than one at a time for resistance management. • Utilize (maintain activity) IR-4 for priority registrations.• Harmonize international tolerances and MRLs. • Harmonize fumigant permit conditions (label interpretations)among California counties (i.e. Ag. Commissioners).

CA Strawberry PMSP: Additional 2018 regulatory priorities• Protect existing chemistries.• Retain methyl bromide for nursery production.• Register new herbicides with effective modes of action.• Reduce current buffer zone requirements.• Re-evaluate fumigant modeling that influences CA regulations.

CA Strawberry PMSP: 2003 & 2018 overlapping educational priorities• Educate growers and regulators (and PCAs) on resistance management.• Educate regulators on systems approaches to using fumigants such as methyl bromide on strawberries.• Educate applicators/growers on safe and efficient application techniques.

CA Strawberry PMSP: Additional 2018 educational priorities• Develop educational materials targeted to minority growers (e.g. Spanish, Mixtec, Hmong, etc.)• Collaborate with CA Association of Pest Control Advisors (CAPCA) and other organizations in educating growers and public• Educate regulators about strawberry growing practices and pest management issues

Thank you!!