major as well as minor viral disease of cereals, legumes, oil-crops, vegetables has been listed. The major research works done these diseases has been also included along with first report.

1. Introduction
The unique agro-ecological zones favored by altitudes, topography, and aspect within the country
offer an immense opportunity for growing different types of fruits, vegetables, flowers, spices and
other plantation crops (Thapa & Dhimal, 2017). Cultivation of various vegetables is one of the
most potential income generating sources for the livelihood of the majority of the farmers in Nepal.
Diseases are one of the major constraints for the successful cultivation of vegetables in the country.
Epidemic of some of the diseases are causing havoc with negative impact on the economy of the
farmers. In recent years, viral disease problem appearing as the most important diseases for some
of the major vegetable crops (Timila, Joshi & Mahto, 2013). It induces broad range of symptoms
affecting growth, yield and quality of the produce. Incidence and severity of viral diseases is
increasing and new virus like diseases are also emerging while research and studies on plant
viruses are limited in Nepal (Timila et al., 2013).
1. Viral Diseases of Cereals
1.1 Rice
To date, only two viral diseases have been identified in Nepal- rice tungro caused by rice tungro
bacilliform virus (RTBV) and rice tungro spherical virus (RTBV) (Omura et al. 1981) and rice
dwarf caused by rice dwarf virus (RDV), (Omura et al. 1982, Dahal et al., 2008).
1.1.1 Rice Tungro Virus (RTV)
During 1978-79, two rice virus diseases rice tungro, and rice dwarf were recorded from Janakpur
(Hardinath) and Lalitpur (Khumaltar) districts of Nepal, respectively (John et at., 1979). In the
similar pattern, Dahal et al. (2008) conducted survey in 1993 and 1994 and indexing of composite
leaf samples for RTBV and RTSV indicated that rice tungro was primarily restricted to the
Hardinath (Janakpur) and Parwanipur (Bara) regions. In 1994, the tungro incidence in Hardinath
ranged from 4% to 32%. Based on particle morphology and/or serology Omura et at (1981; 1982)
identified the presence of rice tungro bacilliform virus (RTBV) and rice tungro spherical virus
(RTSV) from tungro-like rice plants. Ganesh et al. (2008) reported Nepali isolates resembled more
closely the various tugro isolates from Indian subcontinenet by comparative analysis of viral
proteins and nuclei acids of RTBV and RTSV with other tungro isolates from the South and
Southeast Asia. RTBV and RTSV transmitted by both rice green leafhoppers (Nephotettix

2. virescens and Nephotettix nigropictus) were acquired and inoculated in 30 minutes on adult N.
virescens and had incubation period of 7-10 days in rice plants (Dahal et al., 2008).
Figure 1 Rice tungro bacilliform virus with vector Green leaf hopper
1.1.2 Rice Dwarf Virus (RDV)
During 1978-79, rice dwarf disease was recorded from Janakpur (Hardinath) (John et al., 1979)
and Lalitpur (Khumaltar) (John et al., 1978; 1979) districts of Nepal. Dahal et al. (2008) conducted
survey in 1993 and 1994 indicated that rice dwarf was found in the Kathmandu valley and disease
incidence ranged from 0.1% to 20%. Later, based on particle morphology and/or serology Omura
et al. (1981; 1982) identified the presence of the rice dwarf virus (RDV) from rice dwarf plants.
A comparative analysis of RDV ds RNA of nepali isolate with isolates from the Japan, Korea and
the Philippines indicated that isolates from Nepal and the Philippines had more distinct
electromagnetic pattern than Japanese and Korean isolates (Dahal et al., 2008). Some preliminary
studies on RDV such as inoculation by leafhopper Nephotettix nigropictus (adults and nymphs),
acquisition of RDV, screening of some popular rice lines have been conducted in Nepal (Pradhan
and Khatri, 1980; Upadhyaya et at, 1982), however no further work on rice dwarf virus has been
reported. Dahal (1997), reported some research on rice green leafhoppers (Nephotettix virescens
and Nephotettix nigropictus) has begun to determine their relative abundance and population
characteristics in relation to their potential as vectors of rice viruses. In Nepal the virus is
transmitted by both male and female leafhopper Nephotettix nigropictus in a persistant manner
(John et al., 1979a; Omura et al., 1982). Nymphs are more efficient in transmitting the virus than
adult (Pradhan & Khattri, 1980). Upadhyay and Lapis (1982), observed among the 44 screened
germplasm, 10 are observed to be tolerant while other are moderately to highly susceptible.

3. 1.2 Maize
Virus diseases in maize have been reported in Nepal, but none of the virus diseases have been
unquestionably identified (Subedi, 2015). The suspected virus diseases in Nepal are maize mosaic
and leaf fleck (Manandhar, 1983).
2. Leguminous crops
Grain legumes crops are vulnerable to range of diseases, mostly caused by fungi, parasitic
angiosperms, viruses, and bacteria (Darai, Ojha, & Dhakal, 2017). Survey conducted by the
Rayapati (2016), reported occurrence of the bean common mosaic virus (BCMV) in cowpea,
yardlong beans and rajma beans, mung bean yellow mosaic virus (MYMV) in mungbeans and
French beans and bean yellow mosaic virus (BYMV) in the beans. White fly (Bemisia tabaci
Genn.) transmitted Mungbean Yellow Mosaic Virus has been a serious threat to blackgram,
soybean, mungbean and cowpea production in terai / inner terai and foot hills (Darai, Gharti &
Subedi, 2016). Yield losses up to 100%, 52.6% and 21% have been reported due to MYMV in
blackgram, mungbean and soybean, respectively (Darai et al., 2016).
2.1 Soya bean
2.1.1 Mungbean yellow mosaic virus (MYMV):
Figure 3 Rice plants affected by rice tungro
virus
Figure 2 Rice tungro virus particle

4. MYMV is the important diseases of soybean observed in terai/ inner terai region of Nepal and
abundance of weed hosts specially Ageratum spp has been one of the major causes of high disease
severity in Chitwan, (Darai et al., 2016). Darai et al. (2016),conducted three years (2012-2014)
research on host resistance of soyabean against the MYMV and reported that soybean genotypes
CM9125, G8754, LS-77-16-16, SB0065 and SB0095 showed resistant to MYMV and Chaing
Maw 60-63, CM9133, Dhankuta and SJ-4 were moderately resistant in physical observation.
Figure 4 Mungbean yellow mosaic virus
2.1.2 Soybean mosaic virus:
This disease is characterized by the mosaic, mottling of leaves accompanied by a slight crinkling
and reduction in size, plants become stunted and set a few pods only. Pods and seeds are reduced
in size. It is an aphid and seed transmitted virus that infects soybean plants and causes significant
yield losses (Darai et al, 2017). Management includes the use of virus free seed and control of
aphid vector.
Figure 5 Soyabean mosaic virus

5. 2.2 Mungbean and blackgram:
2.2.1 Mungbean yellow mosaic virus (MYMV):
It is gemini virus, transmitted by white fly (Bemisia tabaci) and important host crops are
blackgram, mungbean, soybean, cowpea and pigeonpea (Darai et al, 2017). The disease prone
areas are hot and humid areas of terai/inner terai and foot hills. Pratikshya and kalyan varieties of
mungbean released by National Seed Board were resistance to mungbean yellow mosaic virus
(Srivastava, 2010). In screening nursery of Mungbean Yellow Mosaic Virus of mungbean and
blackgram , IPM-16 genotype of mungbean were found highly resistant whereas Bari Mash-1,
Bari Mash-2, Bari Mash-3 of blackgram and Bari Mung-2, Pratikshya, Hum 12 genotypes of
mungbean were resistant and BLG 0003-2-1 genotype of blackgram were found moderately
tolerant (Gharti, 2013). Gharti (2013), reported spray of Cow’s milk and leaf extract of mixture of
botanicals were effective to reduced severity, increased hundred seed weight and improved grain
yield.
2.3 Pigeonpea:
2.3.1 Pigeonpea Sterility Mosaic (SMD):
The virus causes mosaic symptoms on leaves and infected plants do not flower thus named sterility
mosaic (Darai et al, 2017). Appearance of dwarf, pale green, sterile plants in isolated pockets is
the most conspicuous symptom of the disease. If infection occurs after 45 days of planting few
branches exhibit disease symptoms while rest of the branches remain normal.

6. Figure 6 Sterility mosaic virus infected pigeonpea cultivars seedling showing chlorosis and mosaic
symptoms and typical crinkled emerging trifoliate with mosaic symptoms (A), SMD affected
pigeonpea cv. Erra kandulu in Chevella pigeonpea field, the plant was about 180 days old showing
complete sterility and proliferation of vegetative growth (B), fresh growth of the ratooned (severe
pruning) plant with severe mosaic and chlorosis symptoms in Mg2 pigeonpea field Chevella (C),
pigeonpea cv. ICP2376 showing ring spot symptoms 15 days after inoculation (D), clear ring spot
symptoms as the plant was growing with infection (E), matred plant with no sterility and foliar
ringspot symptoms (F).
2.4 Lima bean and Kidney bean
2.4.1 Mung bean yellow mosaic India virus (MYMIV):
MYMIV was first reported from Phaseolus vulgaris (Kidney bean) and lima bean (Phaseolus
lunatus) plants showing severe mosaic, yellowing and leaf curling symptoms from vicinity of
Chitwan, Nepal by Shahid et al. (2012) and the incidence of disease was 70-80%.
2.5 Bean
a. Bean Common Mosaic Necrosis Virus (BCMNV):

7. The first report of Bean common mosaic necrosis virus (BCMNV) was from bean with mottle
and leaf deformation, severe mosaic, necrosis, malformation of leaves in Nepal in December
2010 (Pudashini, Shahid & Natsuaki, 2013).
Figure 7 Bean Common Mosaic Virus [Credit: Howard F. Schwartz, Colorado University,
Bugwood.org]
b. Bean Common Mosaic Virus (BCMV):
BCMV has been observed in Bean fields in low incidence and its distribution is mainly in the
mid-hills (as observed in the field visits).
2.6 Pea
Electron microscopic examination of leaf extracts from leaves showing symptoms narrow and/or
curled, and stunting of pea plants at Rampur revealed pea seed‐borne mosaic potyvirus (PSbMV)
(Dahal & Albrechtsen, 1996). Pea leaf distortion virus (PLDV) was also reported from Rampur,
Nepal (Shahid et al., 2017).
2.7 Cowpea
Dahal and Albrechtsen (1996), recorded symptoms of cowpea aphid‐borne mosaic potyvirus
(CABMV) during 1989–1990 at Rampur which was transmitted by both aphids and sap
inoculations. The incidence was higher in the late planted pea crop (January) than those planted
in November and December. Different virus-like symptoms have been reported from the
experimental plots of IAAS farm (Timilsina, 1988; Neupane & Pant, 1988) and farmer’s field of
Chitwan district.

8. 3. Viral Diseases of Fruits
3.1 Citrus
After the importation of grafted citrus from Saharanpur (Uttar Pradesh) in India in the 1960's
Citrus virus and virus-like diseases were reported in Nepal prior to the importation of grafted
citrus, no such diseases were reported (Lama, 1996).
3.1.1 Citrus Triteza Virus (CTV):
The first record of Citrus tristeza virus (CTV) Nepal was in 1971 Knorr & Moin-shah, 1971).
According to Regmi et al. (2001), among two strain of CTV virus found in Nepal first strain is
endemic and causes stem pitting and vein clearing symptoms only on lime and does not show
symptoms in sweet orange and manderian while second strain shows symptoms on sweet orange
and mandarin. Regmi and Shrestha (1993), introduced the practice of shoot-tip grafting to
eliminate viruses from budwood sources. Regmi et al. (2001), found the incidence of CTV (non-
stem pitting strain on mandarin) was about 7.7 percent with several colonies of aphids – which
are vectors of Citrus Tristeza Virus (CTV) in different orchards of Baitadi.
Figure 8 Leaf symptoms in sweet orange seedlings infected with Citrus tristeza virus strains CTV-
B2 and CTV-B6 together and separately. (A–C) Seedlings co-infected with CTV-B2 and CTV-
B6, (D–F) seedlings infected with CTV-B6 alone, (G) seedlings infected with C TV-B2 alone,
(A,D) chlorosis; (B,E) vein corking; (C,F) leaf curl; (G) no symptoms.

9. 3.2 Papaya
3.2.1 Papaya Ringspot Potyvirus:
Shrestha, Lecoq & Albrechtsen (1992), observed mosaic, leaf distortion, oily streaks or spots on
papaya isolated and confirmed papaya ringspot potyvirus-watermelon strain (PRSV-W) from
papaya leaves with mosaic and leaf curl symptoms collected from Chitwan valley during 1988 and
then disease attained epidemic proportion in some regions (Dahal & Shrestha, 1991).
Figure 9 Papaya Ringspot Potyvirus:
4. Oilseed crops
4.1 Broad leaf mustard
Turnip Mosaic Virus (TuMV):
TuMV is observed mainly in the broad leaf mustard but radish and turnip is also affected. It is

10. widely distributed in the mid hills and incidence up to 100% causing total crop failure in some
fields (Shrestha, 1983 & 1984).
Figure 10Turnip mosaic virus in Broadleaf mustard -Surkhet
4.2 Soybean and Groundnut
4.2.1 Soybean mosaic virus (SMV):
The most common virus is soybean yellow mosaic virus among the 3 virus diseases of soyabean
that were found in Nepal (Manandhar & Sinclair, 1982). Manandhar reported soybean mosaic
(SMV) in soybean in Kathmandu valley and terai region (Manandhar, 1979).
4.2.2 Bud blight (TRSP):

11. Manandhar reported Bud blight (tobacco ring spot virus, TRSV) in soyabean in Kathmandu valley
and terai region (Manandhar, 1979). Gharti, Darai & Bastola (2010), reported 6 genotypes PI
94159,G-8754, Dashratpur, SB 0095, CM 9125 and TAMPOMAS were found highly resistance
to Mungbean yellow mosaic virus (Gharti et al. 2010; Shrestha et al., 2011).
4.2.3 Peanut bud necrosis virus (PBNV):
Sharma (1996), conducted yield loss assessment study between 1992 and 1995 at Nawalpur,
revealed that cumulative disease incidence of Peanut bud necrosis virus (PBNV) was 20%; pod
yield loss reached 27.7% and infects during the early stage of crop growth.
Figure 11 Peanut bud necrosis virus
5. Vegetables
5.1 Solanaceous crops
Rayapati (2016), visited and surveyed the farmers fields of Surkhet, Banke, Kaski, Kathmandu
districts of Nepal and identified the Chilli veinal mottle virus in pepper, Tomatto leaf curl New
Delhi virus, Tomatto leaf curl Karnataka virus, peanut bud necrosis virus, tobacco mosaic virus,
cucumber mosaic virus in tomato, potato virus Y, X, S and M in potato.
5.1.1 Potato
Six viral diseases namely Potato leaf roll virus (PLRV), Potato virus S (PVS), Potato virus X
(PVX), Potato virus Y (PVY), Potato virus A (PVA) and Potato virus M (PVM) are known to be
the major potato viruses of economic importance in Nepal (Akius & Kloos, 1990; Ghimire et al,
2016; Ranjit et al., 1994; Sakha et al.,2007). Khatri and Shrestha (2004), tested 21 local cultivars
and the tuber of almost all tested stocks were found infected by virus diseases and cultivars Farse

12. White, Rosita, Khumbule and Lumle Red were superior to Kufri Jyoti in tuber yields. Jumli
Local, Kathmandu Local, Sarkari Seto, Syang Dorje and Tharu Local were cleaned against six
potato viruses (A, X, M,Y, S an and leaf roll) at Khumaltar (Khatri & Rai, 2000).
a. Potato Leaf Roll Virus (PLRV):
They could cause yield loss 12-15% and distributed high in the terai and moderate in the mid-
hills (Dhital, Sakha & Nepal, 2010).
b. Potato Virus S (PVS), Potato Virus X (PVX), Potato Virus Y (PVY), Potato Virus A
(PVA) and Potato Virus M (PVM):
Ghimire et al (2016), evaluated the rate of degeneration due to viral diseases in Cardinal and
Kufri Jyoti and he DAS ELISA results revealed that during third year the presence of PVM and
PVY was highest in Cardinal under and Kufri Jyoti under control treatment condition
respectively. Yield data of three different year showed that there is serious loss (27–46%) on an
average in the subsequent year in the productivity of potato (Ghimire et al., 2016). PVX, PVA,
PVS and PVM disease distribution ranged from 24-27% higher in the terai (24%, 25%, 27%,
25%) but lesser than PLRV and PVY. PVX and PVS incident is comparatively higher in high
hills (Dhital et al., 2010).

13. Figure 12 Potato virus X
Figure 13 Potato virus Y
5.1.2 Tomato
a. Tomato leaf curl virus (TLCV):
The presence of the disease in the western hills was for the first time, suspected in 1992 in CL
1131 (now NCL 1) a popular rainy season tomato variety at Kudule, Baglung. However, the
authentic confirmation of the disease was done only in 1994 (Timila, Joshi & Joshi, 1994; PPD,
1995) after diagnosis using cDNA hybridization in collaboration with Dr. Maxwell (Univ. of

14. Wisconsin) and AVRDC (Timila et al., 1994). Tomato cultivation in rainy season is being
endangered and is becoming less profitable because of tomato yellow leaf curl virus (TYLCV)
infection (Ghimire, Subedi & Green, 2001). The popular tomato variety, NCL 1 for the rainy
season is highly susceptible to TYLCV (Ghimire, et al., 2001). Ghimire et al. (2001), conducted
research at Agriculture Research Station, Lumle to assess the incidence of TYLCV and associated
yield losses in various commercial tomato growing pockets of the western hills during the period
of 1995 and 1997. The study revealed a high incidence of the disease in most tomato growing
pockets and yield losses of 40% or even higher have been reported in some areas like Risingpatan,
Tanahun and Kudule, of western hills of Nepal (Ghimire, et al., 2001). The TYLCV vector,
whitefly (Bemisia tabaci Gen.), was found active throughout the crop growing period in some
commercial tomato growing pockets. Therefore, research on the development of effective TYLCV
management technology is needed to sustain rainy season tomato cultivation in the western hills
of Nepal.
b. Tomato mosaic virus
Prevalent in tomato growing areas causing poor plant growth and also appeared in combination
with other viruses (Timila, Joshi & Mahto, 2013).
c. Cucumber mosaic virus:
Widely distributed in tomato growing areas of the mid-hills. Observed to be major. Severely
affected in some of the fields (Timila et al., 2013).
5.1.3 Pepper (Chilli and Capcicum)
The viral disease problem of pepper in Nepal is complex, more than one viruses attack
simultaneously (Joshi & Shrestha, 1999). Joshi & Shrestha (1999), reported tomato leaf curl virus
(TLCV) by c-hybridization at AVRDC, Cucumber Mosaic Cucumovirus (CMV) and Chilli
veinal mottle potyvirus (CVMV) identified by Double Antibody Sandwich (DAS) ELISA in
Khumatar during their survey in main pepper growing area in the years from 1996 to 1999.
a. Cucumber Mosaic Cucumovirus (CMV):
CMV is Widely distributed in terai, inner terai and midhills and the Incidence ranged from50-
80%. Joshi & Shrestha (1999), found that five and three lines resistant to CMV and CVMV

15. respectively while screening fifteen pepper lines supplied by the AVRDC and locally available
cultivars for CMV and CVMV under artificial condition in screen house at Khumaltar. During
March and September 1989, few dwarf plants of chilies, both sweet pepper and hot chilies (cv.
Pusa jwala) were observed with initial symptoms of dwarf, light green foliage, leaf curl, cupping
upward/downward, and leaf distortion (Dahal, 1990).
b. Chilli Veinal Mottle Potyvirus (CVMV):
Higher Incidence and severity in pepper has been observed at Kathmandu valley (mid hills).
Virus infected plants were more than 80% recorded (Shrestha & Albrechtsen, 1992). In recent
years also, the disease status remaining the same.
Figure 14 Chilli veinal mottle virus in Chillipeppers -Surkhet
c. Tomato Leaf Curl Virus (TLCV):
Timila et al. (1994), also reported the occurrence and distribution of TLCV in tomato and chilli.
Joshi et al. (1997), reported distribution of TLCV in the terai, inner terai, valleys and foothills

16. and incidence ranged from the 20-80%.
Figure 15 Tomato leaf curl virus
5.1.4 Brinjal
Brinjal plants with symptoms like mosaic, reduced and distorted leaves, and short internodes
exhibiting a bushy appearance were observed during first week of September 1989 (Dahal, 1990).
5.2 Cucurbitaceous crops
Cucurbits are the important vegetables grown seasonally and infected my a number of viruses
singly or in combination (Joshi et al., 2012). In Nepal, generally cucurbits were found affected by
more than one virus (PPD, 2005). Joshi et al. (2012), identified the viral diseases of cucurbits
Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus
(YMV) 1 and 2, Squash mosaic virus (SqMV), and Cucumber green mottle mosaic virus
(CGMMV) by Direct antigen coating Enzyme linked immune sorbent assay (DAC ELISA).
Among these viruses majority are mechanically transmissible in the sap of infected plants and
some are seed borne such as CMV, ZYMV, CGMMV and SqMV (Joshi et al, 2012). No chemical
controls are effective against the viral diseases of cucurbits however, treatments as victovirus,
fresh cow milk, anti-v and liposome showed effective to some extent but need further field test for
conformation (Joshi, Timila, Manandhar & Tripathi, 2011).

17. a. Cucumber mosaic virus (CMV):
CMV in cucumber is distributed throughout cucumber cultivated areas of mid-hills in severe form
as revealed by sample received at PPD, Khumaltar as observed in the farmers fields, causing
considerable losses (PPD, 2003-1013). Joshi, Gautam & Timila (2010), tested the cucumber seed
samples collected from the Parvat, Baglung, Syanja, Kski, Mygdi, Bhaktpur, Kavrepalanchowk
and RARS, Lumle for the presence of viruses during 2004 and detected the infection by cucumber
mosaic virus ranging from 2 to 100%. Germination of the seed in growing-on test showed that the
infestation of virus did not affect the seed germination, and it provides enough inoculums for
secondaryspread and high yield loss when conditions becomes favourable (Joshi et al., 2010).
Figure 16 Cucumber mosaic virus
b. Zucchini yellow mosaic virus (ZYMV):
Dahal (1992), observed the field incidence of a virus disease of zucchini squash causing severe
mosaic, vein banding, shoe stringing, distortion of leaves and fruits with occasional blisters was
monitored during 1988-1990 at 12 locations in four districts of Nepal. The causal agent was
transmitted by sap and aphids but was not seed-borne. Electron microscopic observation of
samples collected from infected plants revealed flexuous elongate particles resembling those of
potyviruses (Dahal, 1992). Based on these results, the causal virus was tentatively diagnosed as
zucchini yellow mosaic virus. In field plantings the onset of the disease was earlier and spread
occurred more rapidly in March and April plantings than in one made in January. Spread was more

18. than 8.5% per day during both pre- and post-monsoon seasons. The disease significantly reduced
various yield attributes. The disease was epidemic in most farmers' fields at low elevations (about
250 m) and much less at higher altitudes (>1500 m). Rayapati (2016), visited the farmers fields of
Surkhet, Banke, Kaski districts of Nepal and was able to characterize the Zucchini yellow mosaic
virus (ZYMV) in the cucurbits bottleguard, bitterguard, spongeguard, snakeguard, pumpkin and
squash.
Figure 17 Zucchini yellow mosaic virus in Squash -NARC-ARS, Dasharathpur, Surkhet
5.3 Okra
Okra Yellow Vein Mosaic Virus (YVMV):
YVMV is mainly distributed in terai, inner-terai and valleys of mid hills and incidence is upto
70% (Dahal, 1990). Dahal (1990), reported the virus like symptoms on cultivar Pusa sawani with
reduced leaf lamina and a typical interwoven network of yellow veins and complete chlorosis of
younger leaves at the advance stage.

19. Figure 18 Yellow vein mosaic of okra
6. Spices crop (Cardamom)
Dahal et al. (1988), reported ‘Foorkey’ (dwarf) Large cardamom chhirke virus (LCCV) and
‘Chhirke’ (mosaic or streak) Cardamom bushy dwarf virus (CBDV) disease of large cardamom
as serious problem in cardamom cultivation in Nepal. Paudel et al. (2018), indicated that the dwarf
disease of cardamom was more serious than the mosaic or streak diseases. Paudel et al. (2018),
reported Chirke disease spoliation varied from 0.0% to 17.14% and foorkey disease spoliation
varied from 0.0 % to 37.14 % in various plantation in Baglung District. Disease free planting
materials of large cardamom can be obtained by invitro plant regeneration by multiple shoot
formation from meristemic tissue (Paudel & Subedi, 2008). Management of the disease can be
done by applying commercially available formulation of insect-pathogenic fungi (Beauveria
bassiana) Mycotrol or Biosoft @ 3.0g/l, Vertalec or Inovert or Biocatch (Verticillum lecanii) @
3.0g/l, Prioroty (Paecelomyces fumosoroseus) @2.5ml/l, treatment of rhizomes @ 0.075%
hydroquinone and soil drenching with 0.1% of thiouracil showed virus inhibition (Paudel et al.,
2018).
6.1 Large Cardamom Chhirke Virus (LCCV):

20. The chirke disease is transmitted by mechanical sap inoculation and also by maize aphid
(Ropalosiphum maidis Fitch). The cultivar Kopringe is resistant to chirke.
Figure 19Chirke disease of large cardamom at Rngkhani Baglung
6.2 Cardamom Bushy Dwarf Virus (CBDV):
The primary promulgation of the disease from one area to another is through infected rhizomes
and further spread within the plantation by banana aphids, Pentalonia nigronervosa Cog.,
Micromyzus kalimpongensis (Paudel et al., 2018).

21. Figure 20 Furke diseases cauesd by Cardamom Bushy Dwarf Virus (CBDV)
7. Conclusion and recommendation
Viral disease are also causing the some level of damage to the crop in Nepal and damage level is
increasing as the more number of viral diseases are reported from Nepal. However, there is very
little research works on the management aspect of viral disease so, there needs research regarding
the study in the viral diseases.
I recommend the following points for further virological study in our country:
 Regular survey and surveillance of virus diseases in different crop plants through out
Nepal.
 Detection and diagnosis of viruses in major vegetable crops
 Epidemiological and yield loss studies on important virus diseases of crop plants
 Seed transmission studies on seed-borne virus diseases of vegetable crops in particular
 Host resistance screening
 Alternative management tools for Integrated management

22. References:
Akius, M., & Kloos, J. P. (1990). Viral diseases spread and detection in Nepal. In: Proceeding of
11th European Association for potato Research (EAPR), Edinburgh, UK. 66-67.
Dahal, G., Amatya, P., & Regmi, C. (1988). Plant viruses in Nepal: Status and Prospects. Journal
of Institute of Agriculture and Animal Sciences, 9, 119-126.
Dahal, G. (1990). Occurance of virus and virus-like diseases of crop plants in Nepal. Journal of
Institute of Agriculture and Animal Sciences, 11, 47-75.
Dahal, G., & Shrestha, G. K. (1991). An out-break of a virus-like disease of papaya in Nepal.
Journal of the Institute of Agriculture & Animal Sciences, 12, 121-124.
Dahal G. (1992). Occurrence and epidemiology of a potyvirus‐like disease of zucchini squash in
Nepal, Tropical Pest Management, 38:2, 144-151, DOI: 10.1080/09670879209371672.
Retrived from http://www.tandfonline.com/loi/ttpm19
Dahal, G. & Albrechtsen, S. E. (1996). Some studies on cowpea aphid‐borne mosaic and pea seed‐
borne mosaic potyviruses in Nepal. International Journal of Pest Management 42:4, 337-
344.
Dahal, G. (1997). Leafhopper and planthopper vectors of rice viruses and their management in
Nepal. Integrated Pest Management Reviews, 2, 139-142.
https://doi.org/10.1023/A:1018401101481. Retrived from
https://link.springer.com/article/10.1023/A:1018401101481
Dahal, G., Hull, R., Druka, A., Murao, K., & Uyeda, I. (2008). Biological and molecular
characteristics of rice dwarf and tungro viruses in Nepal. In. R. Tess, P. H. Eugene, & S.
K. Gurdev (Eds). Rice genetics III: proceedings of the third international rice genetics
symposium, Manila, Philippines, (pp 929-933).
https://doi.org/10.1142/9789812814289_0130. Retrived from
https://books.google.com.np/books?id=4wzGCgAAQBAJ&pg=PA929&lpg=PA929&dq
=rice+dwarf+virus+in+nepal&source=bl&ots=VS9qsQvDMu&sig=87GfIfL3ii9dW9IU0
MA_UXXzCik&hl=ne&sa=X&ved=2ahUKEwiZyJbngMnfAhWDVrwKHbUqCukQ6A
EwC3oECAAQAQ#v=onepage&q=rice%20dwarf%20virus%20in%20nepal&f=false.

23. Dahal, G., Lecoq, H., & Albreshtsen. (1997). Occurrence of the papaya ringspot potyvirus and
cucurbit viruses in Nepal. Annual Applied Biology, 130, 491-502 DOI: 10.1111/j.1744-
7348.1997.tb07677.x
Dahal, G., Shrestha, R. B., Khatri, N. K., Fan, Z., & Hull, R. (1993). Incidence of virus diseases
of rice in Nepal. Journal of Institute of Agriculture and Animal Science, 14, 115-116.
Retrived from
https://www.researchgate.net/publication/261363656_Incidence_of_virus_diseases_of_ri
ce_in_Nepal
Dahal, G., Thapa, R. B., Neupane, F. P., Hibino., & Hull, R. (1992). Studies on Rice virus diseases
and their vectors in Nepal. Progress report. Plant pathology department, Institute of
Agriculture and Animal Science, Rampur, Chitwan, Nepal.
Darai, R., Gharti, D. B., & Subedi, S. (2016). Host resistance breeding against the viral diseases
of soyabean in Nepal. International Journal of Environment & Agriculture Research,
2(10), 9-13.
Darai, R., Ojha, B. R., & Dhakal, K. H. (2017). Disease management of major grain legumes and
breeding strategies in Nepal. Advance Plants Agriculture Research,, 6(1), 1‒7. DOI:
10.15406/apar.2017.06.00197
Dhital, S. P., Sakha, B. M., & Nepal, R. B. (2010). Effects of Season on Rapid Multiplication of
Virus-free Plantlets under In Vitro and on Production of Pre-basic Seeds of Potato
(Solanum tuberosum L.) under In Vivo Conditions. Nepal Agriculture Research Journal,
10, 75-82.
Gharti, D. B, (2013). An Overview of Summer Legumes Research and Development in Nepal. In
Proceedings of the 27th
National Summer Crops, 2, 409-416.
Gharti, D. B., Daral, R., & Banstola, B. S. (2010). Identification of level of field resistance to major
diseases in available genotypes of soyabean at NGLRP, Rampur during 2005-2007. In
Proceeding of the 25th Summer Crops Workshop.402-409

24. Gharti, D. B., Subedi, S., & Ghimire, T. N. (2013). Validation of farmer’s Indigenous Knowledge
to Manage Mungbean Yellow Mosaic Virus in Blackgram. In Proceedings of the
27tNational Summer Crops Workshop, 1:1319-322
Ghimire, S. Pandey, S. & Gautam, S. (2016). Study on Degeneration of Potato Seed in Terai
Region of Nepal. Agrotechnology, 5: 149. Doi: 10.4172/2168-9881.1000149. Retrived
from https://www.omicsonline.org/open-access/study-on-degeneration-of-potato-seed-in-
terai-region-of-nepal-2168-9881-1000149.php?aid=83714
Ghimire, S. R., Subedi, P. P., & Green, S. K. (2001). Status of tomato yellow leaf curl virus in
tomato in the western hills of Nepal. Nepal Agriculture Research Journal, 4, 1-4.
https://doi.org/10.20546/ijcmas.2018.703.100
John, V. T., Freeman, W. H., & Shahi, B. B. (1979). Occurance of rice tungro virus in Nepal.
International Rice Research , Newsletter. 4(5)
John, V.T., Heu, M. H., Freeman, W. H., & Manandhar, D. N. (1979). A note on dwarf disease of
rice in Nepal. Plant Disease Reporter, 63(9), 784-785.
Joshi, S., & Shrestha, S. K. (1999). Incidence and distribution of Tomato yellow leaf curl virus
and cucumber mosaic virus in tomato and chilli. Proceedings Third National Conference
on Science and Technology March 8-11, 1999. Royal Nepal Academy of Science and
Technology, 1082-1086
Joshi, S., Gautam. I. P & Timila, R.D. (2010). Cucumber mosaic virus in cucumber seed samples
of Nepal. J. Plant Protection Society, 2, 87-93
Joshi, S., Timila, R. D., Manandhar, C., Manandhar, S., & Tripathi, N. (2011). Viral diseases of
the cucurbits and their management in Nepal.
Khatri, B. B., & Rai, G. P. (2000). Potato Production in Nepal. In PJ Batt, R Lawrence and C
Piggin, (Eds.), Proc. of Improving the Efficiency of Potato Production and Marketing in
Indonesia, the Philippines, Vietnam and Nepal, August 3-4,2000 Adelaide, South
Australia, 59-70.
Khatri, B. B., & Shrestha, S. L. (2004). Some Local Potato Cultivars and their Reaction to Viruses.
In Nepal Agriculture Research. Journal, 5, 19-21.

25. Knorr, L. C. & Moin-Shah, S. (1971). World citrus problems. FAO Plant Prot Bull.
Lama, T. K. (1996). Present status of virus and virus-like diseases of citrus in Nepal. In
International Organization of Citrus Virologists Conference Proceedings (1957- 2010).
13(13).
Manandhar, J. B., & Sinclair, J. B. (1982). Occurrence of soybean diseases and their importance
in Nepal. FAO plant protection Bulletin, 30(1):13-16.
Manandhar, K. L. (1979). Report on soyabean diaseses. Summer crops seminar, parwanipur, Feb
25, 1980.
Manandhar, K. L. (1983). Investigation of maize diseases in Nepal - I: Identification and
prevalence. Journal of Institute of Agriculture and Animal Science, 4, 45-56.
Omura, T., Inoue, H., Pradhan, R. B., Thapa, B. J., & Saito, Y. (1982). Identification of rice dwarf
virus in Nepal. Tropical Agriculture Research Quarter, 15 (3), 218-220.
Omura. T., Inoue, H., Thapa, U. B., & Saito, Y. (1981). Association of rice tungro spherical and
rice tungro bacilliform viruses with the rice diseases from Janakpur, Nepal. International
Rice Research Newsletter, 6(6), 12-14.
Paudel, J., Belbase, S., Gautam, S., Bhusal, R., & Kumar, S. (2018). The Effect of Viral Diseases
of Large Cardamom (Amomum subulatum Roxb.) on Production and their Management.
International Journal of Current Microbioogy and Applied Science, 7(3), 855-860
https://doi.org/10.20546/ijcmas.2018.703.100
Poudel, N. S., & Khanal, K. (2018). Viral diseases of crops in Nepal. International Journal of
Applied Scienceand Biotechnology, 6(2), 75-80. DOI: 10.3126/ijasbt.v6i2.19702
PPD. (1995). Annual report 1994/95. Plant Pathology Division (PPD), Nepal Agricultural
Research Council, Lalitpur, Nepal.
PPD. (2005). Annual report 2003/2004. Plant Pathology Division (PPD), Nepal Agricultural
Research Council, Lalitpur, Nepal. 39-40.

26. Pradhan, R. B., & Khatri, N. K. (1980) Report of occurance of rice dwarf virus in Kathmandu
valley. Paper presented at the & 8th summer crop seminar, 1977-78. Department of
agriculture, Harihar Bhawan, Lalitpur.
Pudashini, B. J., Shahid, M. S., & Natsuaki, K. T. (2013). First report of bean common mosaic
necrosis virus (BCMNV) infecting sweet bean in Nepal. Plant Disease, 97(2), 290-290.
DOI: 10.1094/PDIS-08-12-0741-PDN.
Ranjit, M., & Rai, G. P., & Manandhar, A., & Pandey, V. (1994). Virus testing and elimination of
viruses from some local cultivars of potato (Solanum tuberosum) in Nepal. In E. T. Rasco,
F. B. Aromin & C. H. Balaltro, (Eds), Proceedings of 4th Asian Potato Association(APA)
Triennial Conference, 5-7 Jul. 1994,. Daekwonryeong, Korea. 95-99.
Rayapati, N. (2016). Virus disease in vegetables in Nepal. Progress report, March, 2016.
Regmi, C. & Shrestha, S. (1993). Modification of Shoot Tip Grafting technique for increasing
efficiency of successful grafts. In International Organization of Citrus Virologists
Conference Proceedings (1957-2010), 12 (12).
Sakha, M., Rai, G. P., Dhital, S. P. & Nepal, R. B. (2007). Disease-free pre-basic seed potato
production through tissue culture in Nepal. In Nepal Agriculture Research. Journal, 8, 7-
13.
Shahid, M. S., Pudashini, B. J., Khatri-Chhetri, G. B., Briddon, R. W., Natsuaki, K. T. (2017).
Molecular characterization of a distinct monopartite begomovirus associated with
betasatellites and alphasatellites infecting Pisum sativum in Nepal. Virus genes 53(2): 300-
306. DOI: 10.1007/s11262-016-1424-9
Sharma, B. P. (1996). Current status of research on legume viruses with special reference to
groundnut viruses in Nepal. In 4. Meeting of the International Working Group on
Groundnut Virus Diseases in the Asia-Pacific Region. KhonKaen (Thailand). 12-14 Mar
1995.
Sharma, S. & Ghimire, S. R. (1996). Plant disease monitoring and disease diagnosis, 1994/95.
LARC Working Paper (Nepal).

27. Shrestha, K. (1983). Major diseases and control of vegetable crops. Proceedings of Second
Workshop Seminar on Vegetable Seed Production. Jan 31 to Feb 4, 1983, Kathmandu;
Vegetable Dev. Division, HMG, Nepal.
Shrestha, S. K. (1984). Study on mosaic disease of broad leaf Mustard and other cruciferous
vegetables in Nepal. Nepalese Journal of Agriculture, 15, 155-164.
Shrestha, S. K., & Albrechtsen, S. E. (1992). Identification of new virus diseases in Nepal. FA0
Plant Protection Bulletine, 40,167-170.
Srivastava, S. P. (2010). Highlights of grain legumes research in Nepal, 2004- 2005. In Proceeding
of the 25th Summer Crops Workshop, 292-297.
Subedi, G. D., & Paudyal, K. P. (2008) In Vitro Plant Regeneration of Large Cardamom (Amomum
subulatum Roxb.) for Virus Elimination. 5th National seminar on horticulture, June 9-10.
Subedi, S. (2015). A review on important maize diseases and their management in Nepal. Journal
of Maize Research and Development, 1(1), 28-52 DOI: 10.5281/zenodo.34292
Thapa, M. B., & Dhimal, S. (2017). Horticulture Development in Nepal: Prospects, Challenges
and Strategies. Universal Journal of Agricultural Research 5(3): 177-189. Retrieved from
http://www.hrpub.org DOI: 10.13189/ujar.2017.050301
Timila, R. D., Joshi, S., & Mahto, B. N. (2013). Plant Virus Diseases in Nepal: Current Status
and Future Strategies. Presentation. Plant Pathology Division, Nepal Agriculture Research
Institute, Nepal Agricultural Research Council, Khumaltar. Retrived from
https://studylib.net/doc/5581488/plant-virus-diseases-in-nepal--current-status-and-strateg.
Timila, R. D., Joshi, S., & Shrestha, K. (1994). Report on leaf curl virus in tomato and chili crop
in Nepal. Paper presented at SAVERNET midterm workshop held at Nangalore. India.
September 12- 15, 1994.
Upadhyay, B. P., & Lapis, D. B. (1982) Tetep: a potential source of resistance to rice dwarf virus
in Nepal. International Rice Research Newsletter, 7(5), 7-9.
https://www.google.com/search?biw=1366&bih=588&tbm=isch&sa=1&ei=gcFkXJOMGciy9Q
P6xp34CA&q=rice+tungro+spherical+virus&oq=rice+tungro+virus&gs_l=img.1.3.0l2j0i

28. 7i30l2j0i8i30l2j0i24l4.24262.27007..28723...0.0..0.245.2600.2-12......1....1..gws-wiz-
img.oygR4uQ7dsU#imgrc=prn-QxQm2vOXLM:
https://www.growveg.co.uk/plant-diseases/uk-and-europe/bean-mosaic-virus/
https://www.nature.com/articles/s41598-017-11958-8
https://www.researchgate.net/figure/Leaf-symptoms-in-sweet-orange-seedlings-infected-with-
Citrus-tristeza-virus-strains_fig2_319396008
https://www.researchgate.net/publication/261363656_Incidence_of_virus_diseases_of_rice_in_
Nepal [accessed Sep 28 2018].
https://www.sites.google.com/site/msfcentroamerica/plagas/groundnut-bud-necrosis-virus