1. Claude Fauquet GCP21 Cambodia; Sept 18, 2018
Setting the stage for the Regional Workshop : the CMD Control Plan in Mainland SEA
Claude Fauquet
GCP21
Cambodia; Sept 18, 2018

2. South East Asia is the second most cassava productive region in the world with 80mt/y
Thailand is #1-31mt/y, Indonesia #2-21mt/y, Vietnam #3-11mt/y, and Cambodia is #3-11mt/y

3. Evolution of Indochina Cassava Production
The cassava production of countries in IndoChina is indicated in orange, while the harvested area is in blue and the yield in green. Production has increased 30x (55mt/y), harvested areas 10x (2.5mHa) and yield 2x (21t/ha).

4. Evolution of Cassava Area, Yield and Production in Cambodia and Viet Nam
The great increase in cassava production in both Cambodia and Viet Nam (70x and 5x)(yellow) results from the conjunction of increase is surfaces (20x and 2x)(blue) with a doubling or more in yield (3x and 2x)(green). New land for cultivation was open by the government for relocated farmers, and adoption of KU50 or related varieties substantially increased yield.

5. First Report of CMD in Cambodia

6. Cassava in Cambodia
Province 
Area 2016
Production 2016
Battambang 
125,593
3,769,266
Banteay Meanchey 
108,100
2,235,756
Kratie 
66,102
1,420,387
Uddar Mean Chey 
60,132
1,151,240
Pailin 
59,087
1,477,175
Kampong Thom 
54,039
1,176,919
Tbong Khmum 
53,690
1,159,870
Pursat 
28,585
571,700
Kampong Cham 
23,110
337,114
Siem Reap 
20,735
328,143
Preah Vihea 
20,175
229,062
Rattanakiri 
17,263
290,842
Steung Treng 
13,428
268,560
Mondulkiri 
11,275
202,950
Svay Rieng 
9,533
149,011
Takeo 
1,830
26,790
Prey Veng 
947
14,205
Kampot 
811
3,615
Kampong Chhnang 
425
2,428
Koh Kong 
106
1,667
Kampong Speu  91
2,677
Prah Sihanouk  40
598
Kep  19
221
Phnom Penh  10 53
Kandal  -
675,126
14,820,249 .
The cassava production in Cambodia is largely localized close to borders of Thailand (west) and Vietnam (East), where most of the production is exported as fresh roots or dry chips. The CMD infected zone is in the east of Cambodia covering 5 Provinces. The yellow arrows indicate major trading routes for cassava roots and stakes.

7. CMD and Cassava Density
Cassava is not planted uniformly in SEA. The density can be calculated from 0 to 75 Ha per km2. The development of a virus epidemic is related, among other factors, to the virus pressure. The virus pressure is the result of the number of infected plants per surface unit and the number of whiteflies per plant. In other words the more infected plants we have in a region and the more new infections will occur in that region if the insect vectors are enough to transmit the disease. The cassava density and the virus pressure should therefore be considered in a control plan.
CMD infected fields only represent a maximum of 8% of the surfaces and compromise probably only 150,000 tons of cassava production. .

8. Whitefly populations in Cambodia

9. Whitefly populations in Vietnam

11. Cassava Mosaic in Cambodia
Mild symptoms
Healthy Plant
Severe symptoms

12. Cassava Mosaic in Cambodia
Newly infected Plant
Healthy Plant
Plant infected from stakes
In the same field it is possible to find plants infected by cuttings or with new infection from whiteflies.

13. Cassava Mosaic in Cambodia
Dr. Phirun Ive, holds a perfectly healthy plant (left) and one infected through cutting (right) from the same field in Kratie.

14. Cassava Mosaic in Cambodia
Field infected with very high percentage and with relatively mild symptoms in Kampong Province.

15. Cassava Mosaic in Cambodia
Effective management of cassava with maize, with less than 2% infected plants

16. Cassava Mosaic in Cambodia
Fresh Root Transportation to Vietnam
Stake Transportation
from Vietnam
Cassava root stock at a trader place in Stung Treng Province

17. Cassava Mosaic in Cambodia
Transportation of stakes from Vietnam
Cassava Mosaic in Cambodia
Transportation of stakes from Vietnam
Severe symptoms of CMD
from leftover stakes
Whiteflies on cassava leaf

18. Conclusion The following points seem to be clear:
CMD was most probably introduced in north east of Cambodia from an unknown origin (presumably India-Sri Lanka).
CMD in 2016 was restricted to 3 provinces in North East Cambodia, no recorded spread in Vietnam nor in Thailand.
CMD in 2017 is spreading quickly; CMD present in 5 provinces in East Cambodia and at least one in Vietnam. With frequencies varying from 1% to 100% and severity from 1 to 4.
CMD in 2018 is spreading further to 7 provinces in Cambodia and 5 provinces in South Vietnam
The disease is mostly spread by infected cuttings, although whiteflies are present, they play a minor, but important role for the spread of CMD.

19. Conclusion…
The fact that the CMD spread can reach a large territory in short period of time, and the fact that the spread is mostly done through cuttings is calling for a virus-free plant material control plan.
Several initiatives have been taken; JICA, CIAT, FAO, ACIAR, but none at the level required to control the disease.
There is a need to set-up a regional project because viruses do not stop at borders and because there is a lot of traffic of cuttings, at least between Cambodia and Vietnam.
Thailand, Laos, Cambodia and Vietnam should all be enrolled in the plan.
GCP21 could serve as a catalyzer to promote the development of this regional plan.

20. Justifications for a Regional Plan of Control
Cassava Potential in the region. The total production of cassava in the region is now above 50Mt/y and this production continues to grow.
The total number of cassava farmers involved in the region is unknown but can be estimated between 1 and 1,5 million farmers.
The price of fresh cassava roots is variable ($50 to $120 in 2018) and therefore the total production represents between $2.5-$6 b/y of income for the farmers.
Thailand and Vietnam starch production, representing another income in the region estimated to $4-5 b/Y.
The potential impact of CMD on cassava? Experts agreed that in Africa losses could be estimated to an overall 30% of the production. A 30% impact would cost several billion dollars to farmers, to the industry and to the countries in the SEA region and may in fact jeopardize the whole cassava industry if prices of roots go below $60;
CMD difficult to control. CMD cannot be controlled by biological control, nor by chemical, only genetics can control it, which will be very long to transfer into SEA varieties.
Thailand and Laos should be involved. Even though CMD may not be present in Thailand and Laos, it is a matter of time before it would happen. Thailand has much to offer in term of R&D support, and improved varieties (KU, Rayong and TTDI).

21. Gathering a Consensus for a Regional Plan
Visiting key partners in the region.
- Cambodia: CMD
- Vietnam: CMD
- Laos: no CMD
- Thailand: no CMD
Contacting a variety of partners
- Policy makers
- Ministries of agriculture
- Quarantine services
- Extension services
- Donor agencies
Key points
- blame concept
- ignorance prevails
- lack of R&D
- collaboration indispensable

22. Gathering a Consensus for a Regional Plan
Organizing a regional working group to define and adopt a regional plan of action in September 2018
Location: Phnom Penh
Duration: 1 day presentations + 1 day discussions +2 days for writing the plan
Tentative Dates: Sept 18-20, 2018
Countries participant: Cambodia, Thailand, Vietnam, and Lao
International experts: UK, Nigeria, Tanzania, Germany, USA, India
Participants: SATREPS-JICA, CIAT, FAO, GIZ, IITA, TTDI, KU, scientists, and plant protection and extension service officers of each country
International Donors Representatives: AsDB, IFAD, UNDP, ACIAR, FAO, GIZ, AFD, EU…
Objective: production of an agreed single regional control plan of action for 5 years

23. Key points of a Regional Control Plan for CMD
Plan to control CMD
The recent outbreak of CMD in and the fact that the epidemic seems driven by stake contamination is calling for a virus-free based control plan.
Immediate actions:
Common agreement about a regional alliance of the 4 countries through a stake holder meeting
International communication about the situation and needs for the plan.
Communication campaign to reach farmers and traders to get their participate to the plan.
Surveillance system phone-based with symptom pictures
Mapping of the distribution/severity of CMD per district/province
Testing CMD resistant plants from India
Short term actions:
Multiplying certified virus-free mother plants and distributing/selling certified virus-free stakes.
Set-up of a certified Virus-Free system accepted by all countries
Plan to propagate healthy plants of new improved varieties to distribute in heavy infested region;
Multiplication reference sites in Thailand, Cambodia, Laos and Vietnam of new virus-free varieties.
Multiplication at the provincial level (and/or enrolled companies) to be done for the 2-3 major varieties received from Thailand and Vietnam (India) and virus-free material to be sent to every infected district, and subsequently sold to farmers. Priority given to districts were CMD is the most prevalent.
Assessment of the effect of the plan associated with surveillance
Training of farmers and traders to manage CMD
Extension of the plan to less infected districts
Mid-term actions:
Testing CMD resistant varieties for agronomic and processing properties
Multiplication and distribution of satisfactory varieties
Long term actions:
introgression of CMD2 in major varieties cultivated in the region such as KU50 or derivatives.

25. CMD Workshop on Phnom Penh
1 day of presentations
1 day of discussions with the whole group
½ day of donor round table
1,5 days of writing the plan with a small group of people