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Current studies on divergence and management of pepper yellow leaf curl disease in
Indonesia
INTRODUCTION
Sri Hendrastuti Hidayat{ XE "Hidayat, S.H." } 1 , Sri Sulandari 2 , and Sriani Sujiprihati 1
1 Bogor Agricultural University, Campus Darmaga, Bogor 16680, Indonesia
2 Gadjah Mada University, Yogyakarta 55281, Indonesia
Whitefly‐transmitted geminiviruses (WTGs) has been reported to
infect several crops in Indonesia including tobacco, tomato, chilli
pepper, ageratum, and cucumber. Infection of WTGs in chilli
pepper causes severe crop damage and becoming a major threat
since early 2000. The most unique symptoms associated with the
virus infection involved yellowing and leaf curling, therefore it
was known as pepper yellow leaf curl (PYLC) disease. Biological
and molecular characterisation of the causal agent reveals that
several WTGs are associated with the disease. Disease spread
was very fast due to activity of its insect vector, Bemisia tabaci,
which grows very prominently in the tropic climate. Therefore,
disease control is becoming very difficult. Breeding program for
WTGs resistance varieties is one of major activities in regard to
disease control strategy in Indonesia since commercial cultivars
carrying resistance to the diseases have not yet been released.
Evaluation of chilli pepper genotypes showed that some
germplasms are very promising for development of cultivars
with resistance or tolerance to the disease.
MATERIALS AND METHODS
Analysis of Genetic Diversity. Pepper plant showing typical
symptoms of PYLCV infection were collected from several chilli
pepper production areas in Indonesia. Extraction of total DNA
and PCR amplification was done according to procedure
explained previously (1, 2). Sequence data obtained following
nucleotide sequencing of the PCR product was analysed using
ClustalW program version 1.83 EMBL‐EBI.
Evaluation of 11 commercial cultivars and 27 genotypes of chilli
pepper showed that the symptoms were developed within 2 to 3
weeks after inoculation, although some genotypes required
longer incubation period. Disease incidence was varied among
different genotypes, i.e. in the range of 12 up to 100%. Selection
of potential genotypes was proceeded for further breeding
activity in order to develop resistant varieties for PYLCV.
ACKNOWLEDGEMENTS
This research was supported in part by ACIAR—AVRDC Chilli
Integrated Disease Management Project.
REFERENCES
1. Doyle JJ, Doyle JJ (1999) Isolation of plant DNA from fresh tissue.
Focus 12, 13–15.
2. Rojas MR, Gilbertson RL. Russel DR, Maxwell DP (1993) Use of
degenerate primers in the polymerase chain reaction to detect
whitefly‐transmitted geminiviruses. Plant Disease 77, 340–347.
3. Aidawati N, Hidayat SH, Suseno R, Sosromarsono s (2002)
Transmission of an Indonesian isolate of tobacco leaf curl virus by
Bemisia tabaci Genn. (Hemiptera:Aleyrodidae). Plant Pathol J 18,
231–236.
4. Ikegami M, Morinaga T, Miura K (1988) Potential gene product of
bean golden mosaic virus have higher sequence homologies to
those of tomato golden mosaic virus than those of cassava laten
virus. Virus Genes 1,191–203.
Session 2D—Disease management
Evaluation of Chilli Pepper Genotypes. Inoculation of PYLCV by
B. tabaci was conducted as explained previously (3). Response of
different chilli pepper genotypes was classified into three groups
i.e. resistant, moderately resistant, and susceptible based on
symptoms expression and disease incidence.
RESULTS AND DISCUSSION
Identity of geminivirus infecting chilli pepper in Indonesia was
determined based on their hairpin loop structure and repetitive
sequence found in the common region. These hairpin loop
structure was found in all geminivirus sequences so far (4).
Variability in the structure as well as the length of hairpin loop
region was observed among PYLCV isolates. This may indicate
the possible genetic diversity among WTGs infecting chilli pepper
in Indonesia. Phylogenetic analyses involving 32 sequences
showed that PYLCV isolates can be differentiated into several
clusters. Interestingly, they are all quite different from WTGs
infecting tomato in Indonesia but more closely related to tomato
yellow leaf curl virus from Thailand.
APPS 2009 | PLANT HEALTH MANAGEMENT: AN INTEGRATED APPROACH 49