Upload
others
View
9
Download
0
Embed Size (px)
Citation preview
biosecurity built on science Cooperative Research Centre for National Plant Biosecurity
S.K. Singh1,2,3, M. Hodda1,2,3, G.J. Ash 1,3 & D. Paini 2
1Cooperative Research Centre for National Plant Biosecurity 2CSIRO Ecosystem Sciences
3Charles Sturt University
Biosecurity model for exotic and non-exotic plant parasitic
nematodes
http://commons.wikimedia.org/wiki/File:Soybean_cyst_nematode_and_egg_SEM.jpg#file
biosecurity built on science
Plant parasitic nematodes
Majority are microscopic in size
Occupy various different niches
Variable life cycle and survival strategies
~ 2800 named plant parasitic nematode spp
Nearly 600 nematode spp cause economic damage to plants
- 200 spp listed as quarantinable by at least one country
- Approx. 50 genera
biosecurity built on science
Biosecurity perspective
Plant parasitic nematodes cause documented losses of over $600 million/yr in Australia
Australia currently lacks many damaging nematode species
Increased trade volume and diversity increases risks of invasive species gaining entry
Quarantine measures prevent entry and spread of damaging nematode species
Market access
biosecurity built on science
Objective
To determine nematode species which are likely to become pests in Australia
To establish a methodology for assessing biosecurity risks
biosecurity built on science
Methods Nematode distribution data sources
- CABI crop protection compendium (2010)
- CABI pest distribution maps
- EPPO pest distribution maps
- Peer reviewed publications
- Australian nematodes List (Nobbs, 2003 and McLeod et al. 1994)
Stage 1: SOM analysis using SOM toolbox for MATLAB (Paini et al. 2010)
- 220 species
- 356 regions
- 11x 9 map with 99 neurons (5√n)
biosecurity built on science
Results: SOM regional associations
Aust, Qld, S.Afr, China,
India, Pakistan
NT, Samoa, Tonga,
Mozambique, Sudan,
Brunei, Oman, Panama
11
4
3
2
1
10
9
7
8
6
5
13
12 67
14 25
23
24
18
22
20
16
17
19
15
21
78
26
29
27
33
31
32
89
30
28
40
42
44
43
41
36
34
38
35
37
39
46
48
45
50
49
47
51
52
66
53
55
54
59
57
58
60
61
62
63
64
65
56
90 79 68
69 80 91
71
92 81 70
72
93 82
73
94 83
74
95 84
96 85
97 86 75
98 87 76
77 99 88
NSW, USA,
Florida
SA, Vic, Uzbekistan,
Chile, Peru WA, Japan,
Korea, California
TAS,
Armenia,
Tajikistan
Key
Australian states
Other countries
Empty neurons
biosecurity built on science
Top 10 A1 species
Nematode species SOM Risk index
Hirschmanniella oryzae 0.70498 Heterodera glycines 0.48359 Bursaphelenchus xylophilus 0.43284
Meloidogyne graminicola 0.4088 Ditylenchus destructor 0.35678 Zygotylenchus guevarai 0.35215 Bursaphelenchus mucronatus 0.34025 Globodera pallida 0.32358 Nacobbus aberrans 0.30883 Hoplolaimus (B.) indicus 0.30659
biosecurity built on science
Top 10 A2 species
Nematode species SOM risk index
Present states
Aphelenchoides besseyi 0.68383 NT, Q Trichodorus sp. 0.654493 Q, V, WA Helicotylenchus pseudorobustus 0.60567 S, V, WA Criconemella sp. 0.603433 NSW Rotylenchulus reniformis 0.56097 NT, Q, WA Tylenchorhynchus claytoni 0.558895 Q Globodera rostochiensis 0.51113 V Xiphinema index 0.504903 V Longidorus sp. 0.498932 NSW, Q, V Scutellonema brachyurus 0.4678 NT, NSW, Q, S
biosecurity built on science
Discussion
SOM can be used to determine regions with similar nematode assemblages hence identify potential source of invasive species
The risk levels of internal quarantine species are often greater than the external threats
Internal quarantine can be justified since the nematode species assemblages varied between the states
biosecurity built on science
Nematode - Levels of threat
1. Species causing damage elsewhere and not present in Australia eg. Pale cyst nematode, Soybean cyst nematode
2. Species causing damage but with restricted distribution and under internal quarantine eg. Golden cyst nematode
3. Species emerging as a result of changing crops, practices or climate eg. Root lesion nematode after Cereal cyst nematode
4. Species damaging only under certain circumstances or in restricted areas eg. Pine wilt nematode
biosecurity built on science
Nematode - Levels of threat
5. Pathotypes or races, which differ in host relations and pathogenicity eg. Stem and bulb nematode
6. Poorly known threat from species closely related to known pathogenic species eg. Corn cyst nematode related to Potato cyst nematode
7. Unknown threat from recently-described and currently undescribed species eg. Paradolichodera tenuissima, Pea root-knot nematode, Carrot root-knot nematode
biosecurity built on science
Future work
Detailed analysis of selected species based on
Host availability
Climatic suitability
Biological characteristics
Pathways, trade and interception records
Detection and diagnostic capability
biosecurity built on science
Thank you For more information,
Email: [email protected]
Phone: 02 6246 4417
CRC National Plant Biosecurity for PhD scholarship and travel grant
Acknowledgements
References McLeod R. et al. 1994. Plant nematodes of Australia. 3rd edition,
Department of Primary Industries, Canberra.
Nobbs, J. M. 2003. Plant parasitic nematodes of Australia.
SARDI, Adelaide South Australia.
Paini, D.R. et al. 2010.Threat of invasive pests from within
national borders. Nat. Commun. 1:115 doi: 10.1038/ncomms1118.