Phytophthora species in California restoration sites and wildlands: ecology, distribution, dispersal, management

Transcription

1 Phytophthora species in California restoration sites and wildlands: ecology, distribution, dispersal, management Ted Swiecki and Elizabeth Bernhardt Phytosphere Research Phytophthora species in Restoration Nurseries, Plants, and Wildlands II - 18 May 2017

2 In our last episode: Dec 2014 Arctostaphylos myrtifolia Phytophthora cinnamomi Ceanothus ferrisiae P. cactorum 2 year old Diplacus aurantiacus P. tentaculata Plant nurseries provide nearly optimal conditions for Phytophthora diseases

3 SFPUC + SCVWD sample sites through 2/17

4 Native habitats without restoration plantings

5 Planted 2-3 yr ago P. tentaculata

6 Quercus lobata Phytophthora quercina Planted 14 yr ago

7 Quercus agrifolia (3 planted seedlings): Phytophthora cambivora Phytophthora cinnamomi Phytophthora cryptogea Phytophthora taxon agrifolia

8 Salicornia pacifica Phytophthora humicola, P. humicola X inundata

9 Southern California sampling trip September 2016 Agents detected Nursery of Host species Where detected origin Phytophthora cactorum A Cercocarpus betuloides, Salvia mellifera nursery Phytophthora cactorum A Heteromeles arbutifolia nursery Phytophthora cactorum B Quercus agrifolia nursery Phytophthora cactorum E -> C Quercus agrifolia field planting Phytophthora cactorum C Quercus john-tuckeri field planting Phytophthora sp. nov. or hybrid C Eriodictyon crassifolia field planting P. citrophthora / P. colocasiae group Phytophthora cryptogea complex B Eriogonum fasciculatum, Salvia mellifera nursery Phytophthora nicotianae C Adenostoma fasciculatum field planting Phytophthora nicotianae D Arctostaphylos glandulosa gabrielensis nursery Phytophthora nicotianae D Artemisia californica, Eriodictyon nursery crassifolia, Eriogonum elongatum, Quercus agrifolia, Salvia mellifera Phytophthora nicotianae A Baccharis salicifolia, Populus fremontii, nursery Salix lasiolepis Phytophthora nicotianae C Eriodictyon crassifolia field planting Phytophthora nicotianae C Malacothamnus fasciculatus field planting Phytophthora nicotianae B Salvia mellifera nursery Phytophthora niederhauserii A Eriogonum fasciculatum, Salvia mellifera nursery Phytophthora niederhauserii A Heteromeles arbutifolia nursery Phytophthora niederhauserii E -> C Quercus agrifolia field planting Phytophthora sp. nov. or hybrid E -> C Quercus agrifolia field planting P. cinnamomi / P. parvispora group

10 Phytophthora new species or hybrid P. cinnamomi / P. parvispora group on Quercus agrifolia

11 Phytophthora nicotianae Phytophthora new species or hybrid P. citrophthora / P. colocasiae group Eriodictyon crassifolia

12 Across multiple projects: 60 + Phytophthora species Multiple undescribed Phytophthora species 50 + native plant species N and S California sites Wet to dry locations

13 P. cactorum recovered from sites with removed plants

14 LS 10 cm 20 cm Temperature C /01/ /29/ /24/ /19/ /13/ /08/ PINE Measurement Time of All plots temp data Temperature C /01/ /29/ /24/ /19/ /13/ /08/2015 Hourly readings Measurement Time of All plots temp data C 40 C 35 C Depth, cm: Plot: LS US CE PINE

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16 No detection Phytophthora 1 m from plant m from plant

17 Water sampling clade 6 Phytophthora in stable waters

18 Terrestrial root pathogen Phytophthora detected in runoff or flooding

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20 Clade Phytophthora species Transplant Assoc_veg Water 6 aff. clade amnicola amnicola X canalensis bilorbang ripara riparia X lacustris/cambivora thermophila erythroseptica polonica gregata X megasperma/canalensis sp. nov.? aff. lacustris chlamydospora ripara X lacustris gonapodyides chlamydospora X "erwinii" ramorum inundata cactorum lacustris megasperma cambivora cryptogea complex syringae chlamydospora X drechsleri lacustris X riparia tentaculata plurivora quercetorum chlamydospora X gonapodyides cinnamomi niederhauserii taxon agrifolia citricola complex borealis X "erwinii" hydropathica X parsiana Phytophthora species detected in water, soil/roots, or both

21 2014 P. cambivora

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24 clade 6 Phytophthora appear to colonize water/wet areas very readily Phytophthora amnicola Phytophthora gregata Phytophthora inundata

25 1993: nursery-grown Ceanothus ferrisiae planted P. cactorum P. chlamydospora, P. gonapodyides P. lacustris P. megasperma P. syringae P. "kelmania" P. cambivora P. lacustris 23 years after planting - Apparent infested area covers at least 2.8 ha (7 acres)

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27 Best use of testing is for quality control in clean nursery, not trying to pick out uninfected plants in an infested nursery

28 Bench-level baiting of irrigation leachate -Zoospores swim upward -Water drains from middle of water column -Small water surface area concentrates zoospores

29 Testing limits of sensitivity

30 Developing risk-based BMPs Introduction risk = Inoculum density Volume of contamination Site receptivity

31 Developing risk-based BMPs Data Table=risk function Surface Plot High site receptivity

32 Developing risk-based BMPs Data Table=risk function Surface Plot Low site receptivity

33 Thanks for support and cooperation: USDA Forest Service, Pacific Southwest Experiment Station USDA Forest Service, Forest Health Protection San Francisco Public Utilities Commission Midpeninsula Regional Open Space District Santa Clara Valley Habitat Agency Bureau of Land Management California Dept. of Fish and Wildlife Santa Clara Valley Water District California Dept. of Parks and Recreation California Dept. of Food and Agriculture, Plant Diagnostic Lab Rizzo Lab-UC Davis Garbelotto Lab-UC Berkeley