IJERD – International Journal of Environmental and Rural Development (2021) 12-1

Research article
erdExperimental Study of Extension Impact on Farmers’ KAP
towards Sri Lankan Cassava Mosaic Disease Prevention in
Cambodia
SOVANNARA MOUN
Faculty of Agriculture and Food Processing, National University of Battambang, Battambang,
Cambodia

HISAKO NOMURA
Faculty of Agriculture, Kyushu University, Fukuoka, JapanTAMON BABA
College of Letters, Ritsumeikan University, Kyoto, Japan

THA THAN
Faculty of Agriculture and Food Processing, National University of Battambang, Battambang,
Cambodia

KASUMI ITO*
International Center for Research and Education in Agriculture, Nagoya University, Nagoya, Japan
Email: kasumito@agr.nagoya-u.ac.jp

PAO SREAN
Faculty of Agriculture and Food Processing, National University of Battambang, Battambang,
Cambodia
Received 12 January 2021

Accepted 23 June 2021(*Corresponding Author)

Abstract The Sri Lankan Cassava Mosaic Disease (SLCMD) poses a major threat to thecassava industry in Cambodia, as it can decrease cassava yield by up to 80 percent. As SLCMD
has no clear prescription, and currently, the only remedy is pulling out and incinerating theinfected stems. The government of Cambodia, through the General Directorate of Agriculture(GDA), has moved swiftly to sensitize farmers on the causes, effects, and prevention measuresof SLCMD. The GDA has used various media and methods to disseminate knowledge on
SLCMD. However, effective information dissemination methods for changing farmers’
behaviors in terms of the knowledge, attitudes, and practices (KAP) still remain to be identified.
In this study, we investigate the effectiveness of two knowledge dissemination methods, i.e.,“single intervention”—distribution of printed educational materials (PEMs) and “multifacetedintervention”—distribution of PEMs combined with workshop training. The study was
conducted in Battambang, north-west Cambodia over two periods, from June to October 2019,and from November 2019 to February 2020. In the first period of investigation, 468 farmers
were randomly selected to participate in the study. We formulate the contents of the poster andworkshop based on the “initial” KAP results where farmers had lower KAP. Then, all 468
farmers were divided randomly into three groups, namely “Control,” “Treatment1,” and“Treatment2.” farmers in “Treatment1” were subjected to “single intervention” and those in“Treatment2” were subjected to “multifaceted intervention,” while those in “Control” were
subjected to no intervention. In the second period of investigation, the “second” KAP wasanalyzed to estimate the effectiveness of interventions applied in the first period. The results
show that “multifaceted intervention” is the effective method to improve the KAP of farmers inⒸ ISERD

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Cambodia. Our experience of running such farmers’ workshops and the materials we developed
could be useful to governments, non-governmental organizations, and commercial associations
that are keen to mitigate the effects of SLCMD through appropriate interventions.
Keywords field experiment, extension, KAP, SLCMD, RCTINTRODUCTION
Cassava is the second major income source for Cambodian small-scale farmers after rice. In 2019, thenumber of small-scale cassava farmers in Cambodia was above 300,000 (Codes et al., 2019). From2018 to 2019, land area under cassava cultivation increased from 611 thousand hectares to more than
624 thousand hectares (MAFF, 2019). In 2019, Cambodian cassava yield was, on average,
approximately 27 tons per hectare. The total harvested area was approximately 504 thousand hectares(FAOSTAT, 2019). The corresponding benefit-cost ratio analysis shows that for every 1 riel invested
in cassava farming, a profit of 1.31 riel was realized (Thav, 2017).
However, the increasing number of pests and cassava diseases poses a major threat to the quantityof cassava produce. This may in turn harm local food industries and consequently the national
economies in cassava producing countries (Chanda et al., 2016). For example, cassava crops in Africa
are being attacked by pests (such as the cassava green mite (CGM), the cassava mealybug, and thevariegated grasshopper) and diseases (such as the cassava mosaic disease (CMD), the cassava brownstreak disease (CBSD), and the cassava bacterial blight diseases) (Vanessa et al., 2011). In Africa,
CMD is the most harmful of the cassava diseases. Data have shown that it can reduce cassava yield by
up to 90 percent (Hahn et al., 1980). In Cambodia, the Sri Lankan cassava mosaic disease (SLCMD) isthe most harmful. It was first discovered at a commercial farm in Ratanakiri province, Eastern
Cambodia in May 2015 (Wang et al., 2016). By 2019, approximately 12 provinces had an outbreak of
the SLCMD (MAFF, 2019).
Some of these outbreaks have been attributed to the whitefly and stem transmissions (Vanessa etal., 2011 & Minato et al., 2019). Currently, integrated insect pest and pathogen control methods are
hardly used, owing to little sensitization of farmers on their availability and the trivial effort put by
manufacturers into the manufacture of needed equipment. Biological methods seem to be the popular
insect pest and pathogen control choice among farmers.
Therefore, there is an urgent need for improved uninfected planting tools (Nsiah-Frimpong et al.,2020). To address this situation in Cambodia, many strategies have been employed, including
controlling the movement of planting materials, selecting healthy and uninfected seedlings,
encouraging farmers to regularly check their fields, mapping the infected and non-infected areas, andimproving communication between farmers and local agricultural extension agencies (MAFF, 2017,2019). In addition, the general directorate of agriculture (GDA) has adequately sensitized farmers on
SLCMD via field-day workshops, posters, and information leaflets. Further, the GDA has produced an
educational video clip titled “managing the cassava mosaic disease,” which can also be found on social
media.
To cure infected cassava stems, the National University of Battambang, supported by the Japaneseinternational cooperation agency and the Japan Science and technology agency, has propagated tissue
culture of cassava (Tokunaga et al., 2020). Existing studies have recommended workshop training to
improve the knowledge, attitudes, and practices (KAP) in managing the pests and diseases of cassava(Chikoti et al., 2016 and Nsiah-Frimpong et al., 2020). Disseminating the relevant knowledge tofarmers could be the most splendid strategy for managing SLCMD (Houngue et al., 2018). However,there is no study that can help identify the information that the farmers are lacking. Further, and it has
not been determined which of the information dissemination methods is more effective in changing the
KAP of farmers. Therefore, in this study, we endeavor to identify the knowledge gaps and investigate
the effectiveness of two knowledge dissemination methods, i.e., “single intervention”—distribution ofⒸ ISERD

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printed educational materials (PEMs) and “multifaceted intervention”—distribution of PEMs
combined with workshop training.
OBJECTIVE
The main objective of this study is to evaluate the effectiveness of the current information
dissemination methods compiled by the project in order to examine farmers’ behavioral change interms of the KAP towards pest and disease control. We will determine if the information dissemination
methods have been effective in discouraging the re-use of contaminated seedlings and suggest policychanges that will help mitigate further damage that may be caused by the SLCMD.
METHODOLOGY
Study Site
Battambang was selected as the study site. Battambang is the largest cassava producing province innorthwest Cambodia. The total area under cassava cultivation in Battambang is 112,543 hectares whichis ~ 18 % of the total area under cassava cultivation in Cambodia (MAFF, 2019).

Fig. 1 Study area in Battambang Province, Cambodia
Research Design and Data Collection
The study was conducted over 2 periods—from June to October 2019 and from November 2019 toFebruary 2020 (Fig. 1). In the first period of the investigation, between June and August 2019, 468
farmers were randomly selected to participate in the study. Their “initial” KAP was analyzed,
following which all the 468 farmers were divided randomly into 3 equal groups—“Control,”“Treatment1,” and “Treatment2,” using Stata version 16 (a statistic software). Randomization was
evenly stratified at the commune level by gender, age, education, and knowledge level. Farmers in“Treatment1” received printed educational materials (PEMs) in the form of posters. Those in“Treatment2” received PEMs in the form of posters and were sensitized in educational workshops.
Those in “Control” did not receive any sensitization material. In the second period of investigation, the“second” KAP was analyzed to estimate the effectiveness of interventions applied in the first period.

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For this investigation, we received responses from 310 of the 468 research participants. This is because
158 farmers did not cultivate cassava during the second period of investigation.
1st survey(Jun.- Oct., 2019)
Farmers in
Treatment1
group

Knowledge regarding pest anddisease management disseminatedIntervention
treated with poster
by intervention

2nd survey(Nov.2019Feb.2020)

Intervention treated with workshop andposterNo-intervention or treatment

Farmers inControl group
Knowledge,
Attitude, Practicelevel

Knowledge,
Attitude, Practicelevel (afterFig. 2 Randomized Control Trial (RCT) design for Knowledge treatment)
transfer
Analysis of changing

Table 1 Results of randomization at the commune6 level
GroupsTreatment1
Plov Meas
Treatment2
Ampil 5 Derm
Control
Khleang Meas
Note: Data summarized by the authors

Communes
Sdao
Kdol Tahen
Onderk Herb

Treng
Reaksmey Sangha

Observations
231
157
80

Percentage (%)
49.35
33.54
17.09

Intervention Design
Single intervention - Printed educational materials (PEMs)7:
The PEMs distributed in the form of posters contained text, photos, illustrations, and spaces adorned inbright colors to attract the attention of readers. The majority of the information contained in the posters
was about SLCMD. Specifically, the causes, effects, and prevention measures of SLCMD. Informationon the transmission mechanisms of the disease was put in a conspicuous section of the poster.
Information on the devastating effects of SLCMD in Cambodia and Africa was shown via images andtext. SLCMD prevention and control measures were illustrated by cartoons, which made the poster
more accessible. The designers of the posters took great care to make sure that information visualizedby photos and cartoons could not be misunderstood or misinterpreted. The posters had a horizontal
layout. The size of posters (A3) was carefully decided to enable farmers to easily hang them on walls
and/or fold them in half during sessions of group/community information sharing.
Multifaceted intervention:
The multifaceted intervention involved combined use of PEMs distributed in the form of posters (thesame as used in the single intervention—PEMs) and a workshop. The workshop was held to improve
the knowledge of farmers on pest and disease management. Information disseminated in the workshop
was compiled based on pre-identified gaps in the farmers’ understanding, awareness, and practices.
The gaps were identified in the first survey. Similar to the poster’s design process, the workshop
content was created by the experts of agronomics from the National University of Battambang. The
experts took into account the language, culture, and literacy of the targeted farmers. These farmers;social data were collected during the first period of our investigation. Moreover, the workshops
included a Q&A session where misunderstandings of the audience were clarified. The audience wasalso allowed to share their experiences with SLCMD. We also used the workshops to collect more data
on SLCMD by asking the farmers what they deal with in real life.

7 Printed educational materials in the form of poster will be included in the Annex.

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Questionnaire:
The field survey was conducted in Rattanak Mondol, Reaksmey Songha, Plov Meas, Sdao, Treng,
Onderk Herb, Ampil 5 Derm, Kdol Tahern, and Kleang Meas communes (Table 1), and 468 samples
were collected. There were 5 parts to the questionnaire: the first part was about the correspondents’socio-demographic status; we concentrated on the participants’ knowledge, awareness, and practices inthe second, third, and fourth parts, respectively; the final part focused on the farmers’ understanding ofwillingness to pay for healthy cassava seedlings.
Data analysis methods:
The data were analyzed using Stata version 16. From the ex-ante data (first survey) and the ex-post
data (second survey), we scored the answers as 1 for correct and 0 for incorrect. For questions withmultiple answers, if the respondents chose more than one answer, it would automatically be classed asincorrect and scored as 0. To estimate the effects of the two knowledge interventions (PEMs andmultifaceted intervention), we used the differences between the treatment groups (Treatment 1 andTreatment 2) in the first and second surveys to compare with the difference in “Control” via t-test.
RESULTS
The paired t-test was conducted to compare the differences between before and after treatments,
namely difference-in-difference (DiD) among “Control” to “Treatment 1” and “Treatment 2.” Thedifferences in the means were calculated. Both DiD of mean differences of “Treatment1” versus“Control” and that of “Treatment2” versus “Control” showed statistical significance at a p-value of0.01. Table 2 shows that improved knowledge of whitefly and SLCMD symptoms in “Treatment1” and“Treatment 2” versus “Control” was significantly different at a p-value of 0.01. Likewise, getting toknow the name “whitefly” was significantly different at a p-value of 0.01 in “Treatment 2” and a pvalue of 0.10 in “Treatment 1.” Farmers’ knowledge after receiving dissemination from both “single
intervention” and “multifaceted intervention” increased at a p-value of 0.01.
Table 2 T-test results of Farmers’ Knowledge
Definition of variable
Variable(Correct=1; incorrect=0)

Mean-Diff (2

nd

st

–1 )

Coefficient

Control
Treatment1
Treatment2group (n=51) group (n=165) group (n=94)

Control vs.
Treatment1

Control vs.
Treatment2

KN_whitefly

Whitefly is an insect
pest.

-0.039

0.151

0.351

0.143 ***

0.185 ***

KN_slcmd

Do you know SLCMD?

0.156

0.557

0.861

0.200 ***

0.363 ***

KN_whitename

Name of whitefly

0.140

0.234

0.554

0.068 *

0.226 ***

KN_whiteanswer

Whitefly causing thesymptoms

0.039

0.327

0.489

0.304 ***

0.488 ****** Significant at 0.01 ** Significant at 0.05 *Significant at 0.1- Non-significant

As can be seen from the above table, before the distribution of PEMs and/or workshops, themajority of the respondents were not aware of the precariousness of getting their cassava seedlings
from a neighbor or a middleman. Additionally, they were not aware of the benefits of getting theircassava seedlings from a certified healthy seedling distributor (Table 3). It means that farmers continue
to face the risk of getting infected stems. On the other hand, when farmers are asked “I can dosomething to prevent (cassava) plants, Treatment1 seems to have more positive more than the farmers
in the Control while farmers in Treatment 2 were not significantly different from that of Control.
Moreover, farmers of both Treatment1 and Treatment 2, felt they need more authority advice regarding
SLCMD and farmers’ attitudes of both groups improved at a p-value of 0.01. Treatment 2 felt theimportance of authority advice more than farmers in Treatment 1.
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Table 3 T-test results of Farmers’ AttitudendDefinition of variable
Variable

AT_neighbor’s stem
AT_middle man’sstem
AT_certified healthy(Strongly diagree=1 tostrongly agree=5)
Neighbor's stem can reduce
the risk of SLCMD.
Middle man's stem canreduce the risk of SLCMD.
Certified healthy's stem canreduce the risk of SLCMD.

Mean-Diff (2

st

–1 )

Coefficient

Controlgroup (n=51)

Treatment1
group (n=165)

Treatment2group (n=94)-0.0780.090-0.510-0.745-0.915-0.765-0.486-0.236-0.567

Control vs.
Treatment1

AT_I_can_do_s.th

I can do something toprevent plant.

0.529

0.446

0.557

0.503 ***

AT_authorityadvise

It is important to know
SLCMD.

1.000-0.496-0.5740.568 ****** Significant at 0.01 ** Significant at 0.05 *Significant at 0.1

Control vs.
Treatment2

0.891 ***- Non-significant

Table 4 indicates that the mean of purchasing seedlings for planting from a trusted source
increased for both groups. On the other hand, the mean of timely spraying of insecticide to whitefly inneither group was significantly different. Finally, the mean of removing all cassava debris suspected ofbeing SLCMD in Treatment1 versus Control was significantly different at a p-value of 0.1. Also, it was
not significant in Treatment 2 versus Control, the direction was not to remove the debris. This mightmean that farmers have gotten the wrong impression after receiving the contents in PEMs andworkshops and can be a scope for improvement of the contents in the future training.
Table 4 T-test results of Farmers’ Practice
Mean-Diff (2nd – 1st)

Definition of variable
Variable(Never=1,
Sometimes=2,
Always=3)

Control
Treatment1 group
group (n=51)(n=165)

Coefficient
Treatment2group (n=94)

Control vs.
Treatment1

Control vs.
Treatment2

PR_trusted sources

Purchasing cassava
stem from trusted
sources.

0.098

0.418

0.414

0.320 ***

0.317 ***

PR_insecticidewhiteflyTimely treatment ofwhitely.

-0.2940.000-0.3080.294-0.014

PR_removed_debris

Removing all cassava
debris suspected ofbeing SLCMD-0.254-0.727-0.276-0.472 *-0.022*** Significant at 0.01 ** Significant at 0.05 *Significant at 0.1 - Non-significant

DISCUSSION
Our results show that the dissemination of information via the multifaceted intervention is the more
effective method of increasing farmers’ KAP. Previous studies had indicated that the majority offarmers who participated in workshop training became more aware of the cassava virus diseases (Eni etal., 2019). Nishiah-Frimpong et. al. also emphases the importance of training farmers on integrated
methods of insect pest and disease control (2020). It is also possible that the workshops increased theiroutreach by extending the programs to the less literate farmers. In addition, other studies have positedthat farmers are more susceptible to consume knowledge when it is disseminated by experts (Houngue
et al., 2018).
However, we also found out that neither of the two methods sufficiently improved the attitudes of
farmers toward disease preventive measures. When we asked whether they believe “certified healthystem can reduce the risk of SLCMD,” in the attitude question (Table 3), farmers in all groups slightlyⒸ ISERD

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shifted from disagreeing to agree; however, it was not statistically significant. On the other hand, when
we asked their purchasing behavior in the practice question (Table 4), farmers indicated that theywould purchase items for the next propagation from trusted sources. It could suggest that the majorityof them did not believe that purchasing the seedlings from trusted sources can reduce the risk of
SLCMD, and they would still face potential infection after purchasing healthy stems. On the other
hand, farmers both in Treatment1 and Treatment2 would purchase stems for next propagation fromtrusted sources. It indicates that they are more aware of the potential risk of SLCMD even for healthy
seedlings, but still purchasing stems from a trusted source is important to reduce the risk of gettingstems infected from seedlings. Another reason could come from the fact that although multifacetedintervention enabled farmers to understand the importance of purchasing the seedlings from trusted
sources, the majority of them did not believe that purchasing the seedlings from trusted sources can
reduce the risk of SLCMD. noticeably, the choice of cassava seedlings for the majority of the farmers
depends on their agronomical traits, such as tuber yield, fast harvesting, resilience in the soil, andadaptability to drought (Bentley et al., 2017). Also, the reluctance of farmers to purchase seedlings
from trusted sources can be attributed to the farmers realizing that purchasing seedlings from a trusted
source cannot by itself reduce the risk of SLCMD transmission unless farmers implement regularmonitoring and pest treatment management.
Moreover, the workshop disseminated information on well-known SLCMD symptoms and how to
identify uninfected cassava seedlings for the next planting session. Farmers who could not comearound to purchasing seedlings from trusted sources were taught how to propagate their own stems as
an alternative mitigation measure of reducing the spread of SLCMD (Mulenga et al., 2016). The
workshop with the poster group did significantly improve farmers’ practices, for example, purchasing
cassava seedlings from trusted sources. Our findings are consistent with those of a study conducted in
Nigeria (Ebewore and Isiorhovoja, 2019), which acknowledged that training is a major source of
information to cassava producers, and without training, only approximately 17.0% of the farmers will
(N=569) practice disease management.
Further, the study revealed that although spraying insecticide the whitefly is crucial to curbing the
spread of SLCMD, farmers were not spraying the insecticide. The two possible explanations are: (1)farmers have unsuccessfully tried to spray the insect before and had eventually given up; (2) farmers
do not have sufficient finances to spray the insect. Previous studies showed that approximately 91.1%(N=90) of farmers were familiar with insect pests and diseases as causes of significant damage to thecassava crop, but they could not distinguish between the treatments of insect pests and diseases(Chikoti et al., 2016). From the results, it became clear the need to emphasize the importance of early
treatment of whitefly, as it is the vector of SLCMD spread.
CONCLUSION
The objective of this study was to estimate the effectiveness of knowledge dissemination methods inchanging farmers’ KAP towards pest and disease management. We sought to determine which method
is effective in discouraging the re-use of contaminated seedlings. We also suggest policy changes thatmight help mitigate further damage due to the SLCMD. In general, we found that dissemination of
information via workshop training, combined with the distribution of PEMs is an effective way of
improving farmers’ KAP and, consequently, prevent the spread of SLCMD. Nonetheless, as effective
as workshop training combined with the distribution of PEMs was, this method did not sway farmers’
KAP completely. In this regard, we suggest that for future training, trainers should emphasize theimportance of early mitigation practices in minimizing yield loss. The emphasis is likely to further
improve farmers’ KAP. To do so, trainers should inform farmers of the actual yield loss per hectare
they are likely to incur and consequent income loss if they neglect the early mitigation. Where possible
trainers should give real-life examples that the farmers can relate to. This way, the farmers will see theⒸ ISERD

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magnitude of the potential yield and income loss. Nevertheless, our experience of running such
farmers’ workshops and the materials we developed could be evolved and improved, and they could be
useful to governments, non-governmental organizations, and commercial associations that are keen to
mitigate the effects of SLCMD through appropriate interventions.
ACKNOWLEDGEMENTS
This research was supported by the Science and Technology Research Partnership for Sustainable
Development (SATREPS) in collaboration with the Japan Science and Technology Agency (JST,JPMJSA1508) and Japan International Cooperation Agency (JICA)
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