Ministry of Agriculture & Rural Development

CARD Project Progress Report

052/04VIE: Management of Phytophthora Diseases
in Vietnamese Horticulture

MS5: THIRD SIX-MONTHLY

July 2006

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1. Institute Information
Project Name
Management of Phytophthora Diseases in Vietnamese
Horticulture
Vietnamese Institution
National Institute of Plant Protection, Hanoi
Vietnamese Project Team Leader Dr Nguyen Van Tuat
Australian Organisation
The University of Sydney
Australian Personnel
Professor David Guest
Date commenced
April 2005

The University of Sydney
Email: In Vietnam
Name:
Dr Nguyen Van Tuat
Telephone:
+84 4838 5578
Position:
Director
Fax:
+84 4836 3563
Organisation
National Institute of Plant Protection
Email:


2. Project Abstract
training brochures, posters and manuals developed by the Vietnam partner institutes have
been submitted with this report. In February 2006, the Australian partners and scientific
staff from SOFRI and NIPP visited farmer trials established through FTRDC and associated
Plant Protection Departments. Gardens and farms visited were located in Hue (citrus),
Quang Binh Province (black pepper and rubber), Quang Nam Province (black pepper) and
Quang Tri Province (black pepper). This provided an opportunity for scientists from the
three collaborating Vietnamese institutes to establish contacts and to discuss their
experiences in disease diagnosis, management and the establishment of PAR trials.
Scientists from the north and south of Vietnam were also able see in the field symptoms
caused by Phytophthora on crops not grown in their own regions. At each of the farms
integrated disease management options had been established based on techniques learned
during the Extension Training and Farmer Workshops and through PAR trials. Farmers
were generally keen to learn about diseases and their management. The information
presented in this report addresses the targets required to fulfil the fourth and fifth milestones
of this CARD project.
4. Introduction & Background
A diverse range of horticultural crops are grown in Vietnam. Tropical fruit trees are
concentrated in the northern and southern parts of Vietnam and temperate crops in the
northern and central highlands. The range of climatic conditions also provide an ideal
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climate for many Phytophthora species, and the genus Phytophthora is responsible for
extensive economic damage in a wide range horticultural crops throughout the country with
large reductions in yield and significant economical losses.
Information on the occurrence and distribution of Phytophthora species present in Vietnam,
disease transmission and progression, and suitable control methods is lacking. Expertise in
the diagnosis and management of Phytophthora diseases, including appropriate quarantine
procedures, is also limited. A strategic approach to the future study and control of
Phytophthora diseases is needed. This project aims to improve smallholder productivity and
alleviate poverty, especially in the Mekong and Central Coast regions by improving the

Selected staff will also be given an opportunity to undertake a study tour to Australia where
they will learn about nursery best practice and orchard management, as well as advanced
techniques in pathogen identification and research training. Two scientistis (Mrs Nguyen
Thi Ly (NIPP) and Dr Nguyen Van Hoa (SOFRI)) visited Australia in July 2005 and Mr
Doan Nhan Ai (FTRDC) in July 2006 to participate a training and study tour to examine
nursery best practice and horticultural production in southern Queensland, and for further
training in Phytophthora diagnostics. This will build institutional capacity and aims to
maximise the long-term benefits to each institution.
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5. Progress to Date
5.1 Implementation Highlights
A detailed implementation of the project progress to date is provided in the attached
Progress Report Logframe (Appendix I).

The fourth and fifth milestone has been reached with the following targets implemented:
1. Promotion of disease management awareness among farmers. Brochures and training
manuals are enclosed with this report;
a. Prior to this project the understanding of diseases and availability of options for
disease control was limited in some areas.
b. Farmers who attended the extension workshops are adopting the new control
measures they have learnt.
2. Establishment of PAR trials in the north, central and southern regions of Vietnam by
scientific and extension staff from NIPP, FTRDC, SOFRI and Plant Protection Division
offices (Appendix II).
a. Farmers are keen to participate in the PAR trials.
b. Because the PAR trials have been carried out according to seasons (for example
from October to December 2005 and from February to March 2006 in the
northern provinces) results and only preliminary observations are available on
the effect of various control measures disease incidence, yield and fruit/product
quality.

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Improvement of smallholder knowledge
a. Greater understanding of factors that contribute to disease
b. Capacity to select from a variety of disease management options
c. Reduced disease and increased yield
5.3 Capacity Building
1.
Visit to Hue by Vietnamese scientists from NIPP and SOFRI and the Australian
partners.
Dr Nguyen Minh Chau (SOFRI), Dr Ngyuen Van Hoa (SOFRI), Mrs Nguyen Thi Ly
(NIPP), Mr Nguyen Vinh Truong (HAU) and the Australian Project Partners visited the
farmer trials organised through the FTRDC-Hue (Mr Doan Nhan Ai). This provided a
unique opportunity for the Vietnamese project partners to meet and establish stronger
networks. It also provided the opportunity for the scientists from the north and south to
observe diseases and disease management practices of plants that do not grow or occur in
their region.
2.
Presentation of seminars at Hue Agricultural University
Dr Andre Drenth and Professor David Guest presented seminars at Hue Agricultural
University in February 2006.
a. Summary of seminar by Andre Drenth: "The World of Phytophthora".
The seminar presented an overview of Phytophthora species and Phytophthora diseases, and
the economic damage they cause in Horticulture in Vietnam. The aim of the seminar was to
expose staff and students to disease symptoms and make them aware of the enormous
economical and social impact these plant diseases have on smallholders in Vietnam and
elsewhere in south east Asia.
This seminar gave basic background biology of Phytophthora and the life cycle of these
pathogens. The major diseases caused by different Phytophthora species on a range of
different crops including; rubber, pepper, capsicum, durian, longan, coconuts, cocoa,
pineapple, papaya, coconut, citrus and potato, were discussed using slides with pictures of

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Capacity Building at NIPP, FTRDC and SOFRI
Participants at NIPP have learnt techniques to isolate and identify, and have subsequently
isolated, Phytophthora from root and soil of diseased plants.
Baiting techniques have been used to observe the release and development of zoospores.
This highlighted the capacity of the pathogen to spread in the field.
Composted animal manures and the fungicide AgriFos have been applied in the field by
NIPP to test their ability to manage Phytophthora diseases.
5.
Farmer Participatory Action Research Trials
Farmer Participatory Action Research Trials have been established in each of the three
regions. Details of the PAR trials associated with NIPP and FTRDC were provided in the
12 Month Progress Report. Details of the SOFRI extension and farmer trials are provided in
this report. A total of 165 technical extension staff and farmers participated in the training
workshops organised by SOFRI, bringing the total number trained so far to 385 participants
in the farmer training workshops (the project target was 375). The trials are currently being
monitored. Because the trials are conducted in the field, and therefore dependent on
seasonal and climatic factors (for example, trials by NIPP were established between
October and December 2005 and February and March 2006) details of the effectiveness of
treatments are not yet available.
Farmers have been very receptive to the project and eager to learn new methods for disease
management in their crops. As a result of this project farmers have learnt to: (a) Distinguish
between diseases caused by different organisms; (b) more effective methods for application
of fungicides; (c) alternative methods for disease management.
Preliminary Observations: NIPP, Northern Provinces
Prior to the commencement of this CARD project, some farmers in the Y-Yen District,
Hanam Province could not distinguish between late blight disease, early blight disease and
bacterial wilt disease on potato. Some farmers in Tam Diep District, Ninh Binh Province
thought that pineapple heart rot disease was caused by bacteria rather than Phytophthora.
As a consequence farmers often applied chemicals that were not appropriate for control of

Preliminary observations: FTRDC, Central Provinces
Before participating in workshops, most farmers did not know about Phytophthora as the
cause of disease. They had no knowledge of diagnosis, dissemination, conditions conducive
to infection and development of disease. As a result the farmers had not applied anything to
control the diseases or they were using incorrect methods for disease control. For example,
they had propagated seedlings from mother plants that may be infected with pathogens by
cutting or marcotting (black pepper, pumelo), planted seedlings in poor drainage areas
(pumelo), not removed infected plant parts or fruit from their orchards (particularly in
rubber orchards) and intercropped plants also susceptible to Phytophthora such as taro,
tomato, chilli, eggplant, cucumbers, pineapple or used jackfruits as supports for black
pepper crops. Some of farmers had only applied a chemical measure including Aliette,
Ridomil or Bordeaux fungicides to control diseases but they had not chosen the best
fungicide to effectively control Phytophthora diseases yet.
FRTDC established farmer trials based on the initial knowledge of farmers (just described).
Farmers are very glad to take part in the trials. Some of the farmers who participated in
farmer workshops have implemented methods they learnt in the workshop on their own
because they live far from the PAR trial sites. The effectiveness of cultural measures for
control of Phytophthora including mulching, pruning and increasing application of organic
fertilizers is not obvious. The inclusion of chicken manure for organic control has not been
possible due to the incidence of bird flu in Vietnam. Planting crops on mounds to improve
drainage or planting crop varieties resistant to Phytophthora has not been possible owing to
the establishment of trials in available orchards. Black pepper varieties that are resistant or
tolerant to Phytophthora have not been selected. Phosphonate (Agri-fos 400) injections
have been observed to be more effective in controlling Phytophthora in Thanh Tra pumelo
than Ridomil or Bordeaux painted onto trunk lesions. Phosphonate is also less expensive
than Aliette. However, injecting phosphonate fungicide is not effective in pumelo trees that
are too seriously infected with Phytophthora diseases. The effect of phosphonate on
controlling Phytophthora in rubber trees is not yet clear.
The most difficult issue for farmers has been to detect early disease symptoms, particularly
root rot of black pepper. Early detection of symptoms is very important in pepper because

treatments and the appropriate time has reduced the amount of fungicides that need to be
applied. The option of alternative and preventative methods (such as mounding to improve
drainage, pruning to improve canopy humidity, application of manures to improve soil
health) for disease management also reduces disease incidence and the need for fungicide
application.
6.2 Gender and Social Issues
A greater proportion of participants at the SOFRI training workshops were male (95%) than
female (5%). This has been a common trend in the majority of the workshops at each site.
7. Implementation & Sustainability Issues
7.1 Issues and Constraints
Some farmers were sceptical about using phosphonate, particularly if applied as a trunk
injection, believing it would kill their trees. As a result a limited number of trees (rubber
and citrus) were injected with phosphonate. We believe that in future farmers will become
Comment [MSOffice1]: At FTRDC
and NIPP too?
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more accepting of this form of application when they see the results of phosphonate as a
method for disease management. When asked if they would inject more trees if they could
see a reduction in disease all farmers answered in the affirmative.
7.2 Options
The targets of the fourth and fifth milestones have been met. The project is running well
and no changes are required.
8. Next Critical Steps
The activities that will be undertaken in the next six months are:
1. Visits to NIPP, SOFRI and FTRDC to review farmer training and extension activities.
2. Final workshop in November-December 2006 to discuss outcomes of PAR and farmer
trials.
9. Conclusion
This CARD project aims to reduce crop losses due to Phytophthora diseases through
extension of sustainable and effective disease management recommendations and thereby