This document provides an overview of rice false smut, including its occurrence, symptoms, pathogen, disease cycle, and management. It begins with an introduction and table of contents. Key points include: - Rice false smut occurs worldwide in all rice growing regions. It causes significant yield losses ranging from 10-75%. - The pathogen is Ustilaginoidea virens. Disease development is favored by cloudy, humid conditions during rice flowering. - The disease cycle involves the pathogen infecting rice spikelets and producing spores within smut balls that replace grains. - Management strategies include rouging of infected plants, selecting disease-free seed, optimizing fertilizer and planting

1. 1

2. 2
 Introduction
 Occurrence
 Losses
 Symptomatology
 Pathogen
 Host
 Disease cycle
 Management
 Conclusion
 Future Thrust
CONTENTS
2

3. INTRODUCTION
3

4. Origin and History
4

5. Name References
Ustilago virens Cooke (1878)
Tilletia oryzae Patouillard (1887)
Sphacelotheca virens Omori (1895)
Ustilaginoidea oryzae (Pat.)
Brefeld.
Brefeld (1896)
Ustilaginoidea virens
(Cke.) Tak.
Takahashi (1896)
Claviceps virens (Cke.)
Sakurai.
Sakurai (1934)
Claviceps oryzae-sativae Hashioka (1971)
Villosiclava virens Tanaka et al. (2008)
History
5

6. 6
The disease was first time reported from
Tirunelveli district of Tamil Nadu (India)
Cooke (1878)

7. OCCURRENCE
7

8. World Reference
All rice growing regions of the world including
China, Japan, South-East Asian countries,
North and South America, Burma, Sri Lanka,
Fiji and Africa
(Manthar et al.,
2008)
India
Observed in severe form since 2001 in Haryana,
Punjab, U.P., Jharkhand, Uttaranchal, Tamil
Nadu, Karnataka, A.P., Bihar, Gujarat,
Maharastra, Jammu and Kashmir and
Pondicherry
(Dodan and
Singh, 1996)
Gujarat
False smut has been observed in severe form in
different districts of Gujarat viz., Anand, Kheda,
Vadodara, Navasari and Surat
(Anon., 2015)
8

9. Table 1: Incidence of rice false smut in farmer’s field and seed production plots
Location Variety 2012-13 2013-14 2014-15
No. Of fields
observed
No. Of fields
infected
No. Of fields
observed
No. Of fields
infected
No. Of fields
observed
No. Of fields
infected
Anand Gurjari 11 0 10 1 6 2
GR 11 3 1 7 1 4 1
GR 7 1 0 3 0 4 0
Jaya 2 0 2 0 1 1
GR 101 --- --- 1 0 1 0
Kheda GR 11 2 1 4 1 4 0
GR 12 2 0 --- --- 1 1
Gurjari 8 1 6 1 6 2
GR 3 1 0 2 0 1 0
GR 101 1 1 2 1 2 0
Masuri 1 0 2 0 2 0
Jaya 1 0 4 0 4 0
Ahmedabad Gurjari 9 0 6 0 4 0
GR 7 3 0 2 0 2 0
Jaya 2 0 4 0 2 1
GR 3 1 1 2 1 2 0
GR 11 4 1 2 1 2 0
Vadodara Jaya 1 0 2 0 2 1
GR 11 3 1 10 2 4 1
Gurjari 9 1 12 1 6 2
Masuri 1 0 1 0 1 0
GR 4 1 0 2 1 2 1
GR 101 1 0 2 0 2 0
Navsari Gurajri 2 1 7 1 6 2
Jaya 4 0 5 0 2 1
GR 7 3 0 2 0 2 0
GR 11 1 1 3 1 2 1 9

10. Location Variety 2012-13 2013-14 2014-15
No. Of fields
observed
No. Of fields
infected
No. Of fields
observed
No. Of fields
infected
No. Of fields
observed
No. Of fields
infected
Surat GR 11 1 1 2 1 2 2
GR 3 2 1 4 0 2 0
GR 101 1 0 2 1 2 0
Masuri 1 0 4 0 2 0
Gurjari 2 1 8 1 4 1
Seed production plots
Nawagam Jaya 1 0 3 0 4 0
Gurjari 3 0 4 0 6 0
Masuri 2 0 2 0 2 0
GAR 13 1 0 1 0 2 0
GR 11 3 0 2 0 4 0
GR 102 2 0 1 0 --- ---
GR 104 2 0 1 0 --- ---
GR 3 -- -- 1 0 2 0
GR 4 -- -- 1 0 2 0
GR 6 1 0 1 0
Vyara GNR 13 -- -- 2 0 2 0
Jaya 1 0 2 0 4 0
GNR 3 1 0 2 0
GNR 4 1 0 2 0
GR 7 1 0 2 0 2 0
Gurjari 4 1 4 1 4 1
RRS, Anand Gurjari 2 0 4 0 4 1
Dabhoi Gurjari 2 0 4 0 4 1
Narmada 2 0 2 0
GAR 13 1 1 1 1 2 0
GR 7 2 0 2 0 2 0
GR 11 3 1 2 1 2 1
Anon., 2015Gujarat 10

11. Courtesy: N. M. Gohel11

12. Courtesy: N. M. Gohel12

13. Courtesy: N. M. Gohel13

14. Yield losses
% Losses Reference
India
70-75% Agarwal and Verma (1978)
10-49% Ansari et al. (1988)
0.006-0.084% Anonymous(1991)
7-75% Singh, (2009)
Haryana 2-75%
Ladhalakshmi et al. (2012)T.N. 5-85%
Punjab 10-20%
Gujarat 10-12% Patel et al. (1992)
U.P.
4.25-20% Upadhyay and Singh (2013)
5-80% Singh et al. (2014)
Test weight
28% Singh et al. (1992)
44% Hegde and Anahosur (2000)
14

15. Effect on seed germination
Loss of germination (%)
2.9-6.6 Hu (1985)
38.2 Baruah et al.(1992)
Max. 25.3
&
Min. 12.9
Hegde and Anahosur
(2000)
21.45 Sanghera et al. (2012)
15

16. 16

17. Phylum : Ascomycota
Class Deuteromycetes
Order Moniliales
Family Dematiaceae
Genus Ustilagenoidea
Species virens
17

18. Chlamydospore
Conidia

19. Sclerotia 19Fu et al., 2012

20. Symptomatology
20

21. 21

22. Orange Yellowish green
GreenGreenish black
Colour changes on infected smut balls
Singh (2009)22

23. Infection process of Ustilaginoidea virens (Uv) in rice spikelet
an= anther, fi= filament, lo= lodicules
Fan et al. 201523

24. Host Plants 24

25. HOSTS PLANTS OF Ustilaginoidea virens (Cooke.) Tak.
Host plants Reference
Oryza officinale
Singh (2009)Chionachne koenigii
Digitaria marginata (crab grass)
Echinochloa crusgalli (barnyard grass)
Guo et al., 2012Imperata cylindrica (cogon grass)
25

26. 26

27. Digitaria marginata
Echinochla crusgalli Imperata cylindrica27

28. Disease Cycle
28

29. 29 Hegde and Anahosur, 2000

30. Favourable Condition 30

31. Favourable condition References
Cloudy days
More cloudy days during flowering Rao and Raju (1955) and
Dubey (1985)
Cloudy days along with little precipitation Singh (1976)
Humidity
High relative humidity (92-96%) during flowering Rao and Raju (1955) and
Agarwal (1990)
Highest false smut incidence associated with the high
afternoon humidity (83.5%), rainfall (159.5 mm) and
number of rainy days (16) in the September month
Rautaray (2006)
Temperature
Low temperature and moisture at heading appear to be
involved in the expression of spore balls and disease
Ashizawa et al. 2011, Guo
et al. 2012
Minimum and maximum temperature ranged between
27.08 and 30.43ºC which favours the disease
development
Upadhyay and Singh, 2013
31

32. Scoring system of false smut of rice
category Number of smut balls/ panicles
I 0 Healthy panicles
II 1-2 Smut balls/ panicle
III 3-4 ”
IV 5-6 ”
V 7-8 ”
VI 9-10 ”
VII > 10 ”
Karnataka Hegde and Anahosur (2000)
32

33. Scoring system of false smut of rice
1 2 3 4 5 6 7
33

34. 34

35. Cultural Practices 35

36. Rouguing
(a) (b)
(c)
(a) Field sanitation
(b)Rouging
(c) Selection of seed
36

37. Table 2: Effect of soil types on rice false smut during two successive growing seasons
under field condition
Soil types Growing season
2001 2002
No. Of smutted grains/
tillers
No. Of smutted grains/
tillers
Clay soil 4.67 3
Light soil 6.33 5
LSD at 0.05
Soil type (T) 1.23
Season (S) 1.47
T X S 2.68
Atia (2004)Egypt
37

38. Table 3: Effect of different rice cultivation methods on rice false smut during two
successive growing seasons under field condition
Sowing methods Growing season
2001 2002
No. of smutted grains/
tillers
No. of smutted grains/
tillers
Direct 7.03 4.35
Transplantation 4.88 3.14
LSD at 0.05
Methods (M) 1.67
Season (S) 2.10
M X S 6.164
Atia, 2004Egypt
38

39. Table 4: Effect of different cultivation time on rice false smut during two successive
growing seasons under field condition
Cultivation time Growing season
2001 2002
No. of smutted grains/
tillers
No. of smutted grains/
tillers
Early June 2.67 2.1
Mid June 3.76 2.33
Early July 6 4.33
Mid July 9 5.11
LSD at 0.05
cultivation time (C) 0.993
Season (S) 1.892
C X S 2.142
Atia, 2004Egypt
39

40. Fertilizer Management
40

41. Table 5: False smut incidence and yield under different
nitrogen (N) levels
N Level (kg/ha)
Disease incidence (%) Yield (kg/ha)
1985 1986 1985 1986
0 9.4 16.2 3483 4541
50 10.5 23.0 4883 6204
100 10.6 24.4 5816 6841
150 11.4 27.7 5583 7087
200 12.8 30.4 5316 6541
CD at 5 % 1.4 3.9 501 708
Navsari (Gujarat) Patel et al. (1992)
41

42. Table 6: Effect of different levels of NPK on the incidence of false smut of rice
Treatments Percent Grain
infection
N0P0K0 0.74 (4.83)
N90P40K50 1.04 (5.82)
N90P60K50 1.10 (6.0)
N90P80K50 1.11 (6.01)
N120P40K50 1.62 (7.24)
N120P60K50 1.40 (6.74)
N120P80K50 1.37 (6.89)
N150P40K50 1.95 (7.98)
N150P60K50 1.70 (7.45)
N150P80K50 1.55 (7.11)
SEM+ 0.21
CD at 5% 0.62
Figures in parentheses are angular transformation values
Mohiddin et al., 2012J & K 42

43. Table 7: Effect of different Nitrogen (N) levels on rice false smut during two successive
growing seasons under field condition
N levels Growing season
2001 2002
No. of smutted grains/
tillers
No. of smutted grains/
tillers
40 kg/ feddan 3.11 1.67
60 kg N/ feddan 5.11 4.33
80 kg N/ feddan 7.12 5.33
LSD at 0.05
Nitrogen level (N) 1.532
Season (S) 1.380
N X S 3.562
Atia, 2004Egypt
43

44. Chemical approach
44

45. Table 9: Evaluation of fungicides for the control of False Smut disease of rice
Treatment
False smut
Severity Grain yield
kg/plot
Severity Grain yield
kg/plot
B H B H Nn Hn Nn Hn
Propiconazole 25 EC.
0.1%
2.0 2.0 5.2 5.1 1.4 2.0 4.0 5.2
Hexaconazole 5 EC.
0.1%
2.2 2.5 4.8 4.9 1.8 2.2 4.3 4.8
Kasugamycin, 0.1% 2.6 2.4 4.7 4.5 2.0 2.6 4.0 4.7
Edifenphos 50 EC, 0.1% 2.5 2.7 4.7 4.9 1.7 2.4 4.3 4.7
Copper oxychloride 50
WP, 0.3%
2.9 2.7 4.5 4.9 - - - -
Control 2.8 - 4.4 - 2.2 2.8 4.3 4.4
B= Booting stage, H= Heading stage
Nn= Normal level of nitrogen, Hn= Higher level of nitrogen
Gurdaspur Bagga and Kaur (2006)45

46. Table 10: Optimal application timing of Simeconazole granules for
the control of rice false smut
Fungicides Application
date
Visual false smut
Infected stands
(%)
Infected panicles
(%)
Simeconazole 1.5 G July 1 3.3 (+ 1.7) 0.04 (+ 0.02)
July 8 6.7 (+ 2.2) 0.09 (+ 0.04)
July 15 1.7 (+ 0.8) 0.03 (+ 0.01)
July 22 5.0 (+ 3.8) 0.09 (+ 0.06)
July 29 13.3 (+ 4.4) 0.28 (+ 0.13)
Ferimzone/phthalide August 4 18.3 (+ 10.9) 0.48 (+ 0.32)
Untreated control - 18.8 (+ 5.2) 0.60 (+ 0.19)
Tsuda et al. (2006)Japan
Standard errors given in parentheses
46

47. Table 13: Efficacy of fungicides against false smut of paddy at different stages
Treatment Sprayed at boot stage Sprayed at heading stage
2006 2007 2006 2007
DI
(%)
DS (%) DI (%) DS (%) DI (%) DS (%) DI (%) DS (%)
Copper Hydroxide (0. 1 %) 17.33 0.48 13.30 2.50 60.00 1.52 53.00 4.20
Copper Hydroxide (0. 2 %) 13.33 0.20 12.00 2.00 54.66 2.56 51.09 4.50
Copper Hydroxide (0. 3 %) 5.33 0.04 6.60 1.67 49.33 1.00 46.00 1.00
Copper oxychloride 50 WP 4.00 0.04 2.60 2.00 38.66 2.36 37.00 1.00
Propiconazole 25 EC 14.67 0.36 9.30 2.00 40.00 2.44 37.00 1.00
Copper oxychloride 50 WP/
Propiconazole 25 EC
4.00 0.02 0.00 0.00 33.33 0.20 32.00 0.50
Difenoconazole 25 EC 20.00 0.72 16.00 1.00 44.00 1.40 49.00 4.00
Hexaconazole 5 EC 28.00 1.88 25.30 1.33 48.60 1.04 53.00 4.50
Control 73.33 9.40 54.60 4.33 66.66 3.16 60.00 6.00
CD at 5% 12.51 5.29 11.51 0.27 4.52 NS 5.69 1.02
DI= Disease incidence, DS= Disease severity
Pannu et al., 2010Ludhiana 47

48. Table 14: Effect of fungicides and botanicals on the incidence of false smut and
yield of rice
Treatments Grain infection
(%)
disease control
(%)
Yield q/ha
Copper oxychloride (0.3%) 1.7 (7.5) 54.0 42.2 (40.5)
Prochloraz + Carbendazim (0.2%) 1.3 (6.6) 64.9 44.3(41.7)
Chlorothalonil (0.2%) 1.6 (7.2) 56.7 42.9 (40.8)
Azadirachtin (0.5%) 2.1 (8.3) 43.2 39.0 (38.6)
Azadirachtin (0.3%) 1.9 (7.9) 48.6 41.5 (40.0)
Azadirachtin (0.2%) 2.0 (7.9) 46.0 41.1 (39.9)
Cymbopogon (0.5 %) 2.3 (8.7) 37.8 37.8 (37.9)
Control 3.7 (11.1) - 36.1
SEM+ 0.3 - 2.4
CD at 5% 0.9 - 7.3
J & K Mohiddin et al., 201248

49. Table 15: Effect of fungicides sprayed at different growth stages on false smut and grain yield of
paddy genotype CR 333-6-1 during kharif 2012
Fungicides Infected grain (%) Grain yield (kg/ ha)
Booting 50% PE 100% PE Booting 50% PE 100% PE
Trifloxystrobin 25% +
Tebuconazole 50% @ 0.4 g/l
0.59 0.61 1.02 4650 4700 4400
Kresoxim methyl @ 1 ml/l 0.50 0.64 0.95 4800 4883 4433
Propiconazole @ 1 ml/l 0.43 0.58 0.87 4967 4867 4433
Untreated check 1.18 1.18 1.18 4500 4500 4500
CD at 5 %
Fungicide 0.11 61
Stage of spray 0.07 131
F X SS 0.11 NS
Singh and Sundar, 2015Haryana 49
PE= panicle emergence stage

50. Table 16: Effect of fungicides sprayed at different growth stages on false smut and grain yield of
paddy genotype CR 333-6-1 during kharif 2013
Fungicides Infected grain (%) Grain yield (kg/ ha)
Booting 50% PE 100% PE Booting 50% PE 100% PE
Trifloxystrobin 25% +
Tebuconazole 50% @ 0.4
g/l
0.19 0.23 0.60 5583 5433 5417
Kresoxim methyl @ 1 ml/l 0.21 0.24 0.68 5450 5483 5317
Propiconazole @ 1 ml/l 0.21 0.29 0.36 5600 5533 5383
Untreated check 1.12 1.12 1.12 5267 5267 5267
CD at 5 %
Fungicide 0.08 NS
Stage of spray 0.20 87
F X SS 0.34 151
Singh and Sundar, 2015Haryana 50
PE= panicle emergence stage

51. Table 17: Effect of different fungicides on false smut
Treatment
Booting Heading
2012 2013 2012 2013
Smutted grains (%) Smutted grains (%)
Carbendazim 50WP, 0.1% 2.05 1.61 3.35 2.74
Mancozeb 75WP, 0.2% 3.09 2.98 4.74 4.44
Hexaconazole 5EC,0.2% 1.51 1.50 2.36 2.28
Carbendazim + Mancozeb 0.2% 2.80 2.72 3.78 3.37
Propiconazole 25EC, 0.1% 1.21 0.68 2.09 1.88
Trifloxystrobin 25% + tebuconazole 50% 75
WG, 0.04%
1.46 1.63 2.12 2.21
Kresoxim methyl 44.3SC, 0.1% 2.87 2.45 1.33 1.88
Control 6.84 4.27 8.66 5.38
CD at 5% 0.81 0.84 1.28 1.16
SEM+ 0.26 0.28 0.42 0.38
CV 16.99 19.13 21.44 20.97
Snehlata and Kumar (2015)Pantnagar
Data is mean of three replications, treatment is given as foliar spray
51

52. Varietal Resistance
52

53. 53

54. Table 18: Effect of field inoculation of rice flowers on different
cultivars.
Rice cultivars
Numbers of
grains
inoculated
Number of grains
showing infection
% infection
Zenith 6 1 16.6
Ratna 5 2 40.0
Jaya 6 2 33.3
Tetep 7 3 42.8
Tadukan 9 4 44.4
Karuna 12 6 50.0
Mahsuri 10 5 50.0
Jaganath 7 5 71.2
CRRI (Cuttack) Singh and Gangopadhyay (1981)54

55. Table 19: Effect of false smut incidence on grain yield of different rice varieties
Varieties / Genotypes Smutted balls % Disease severity Grain Wt of 10 panicle (g)
smutted healthy
Jaya 13.1 450.6 21.6 42.2
Rasi 15.2 580.6 19.1 40.0
Pankaj 3.7 26.6 48.2 53.4
IET 6666 4.2 36.1 43.5 50.1
IET 8021 5.0 48.0 47.9 55.2
IET 7564 4.8 56.1 34.3 48.2
Salivahana 5.1 68.3 65.6 46.5
Sial Sali 18.4 958.6 23.9 49.6
Halodhiguri 16.2 748.4 27.5 46.1
Hemacha sali 7.2 289.4 36.4 49.5
Ikora sali 6.9 214.5 37.7 48.4
Mugi sali 5.1 83.6 43.1 49.7
Prasad bhog 7.9 210.9 30.2 41.1
Assam Baruah et al. (1992)55

56. Table 20: Infection range of false smut in paddy varieties
Varieties Mean infection range
Kundlika 0.0 – 72.92
Karjat -
Karjat – 184 -
RDN – 135 – 49 -
Ratnagiri – 3 -
Palghar 0.05 – 19.16
Panvel – 1 -
Madhuri -
Indrayani 0.05 – 5.61
Jaya 0.01 – 22.22
Ratna 0.01 – 39.16
Pawana 0.05 – 14.58
Phule Maval 0.05 – 16.67
Basmati – 370 0.01 – 11.11
Karjat – 2 0.01 – 18.33
Karjat – 3 0.01 – 5.21
PKV – HMT 0.05 – 12.47
Sahyadri 0.00 – 0.01
Radhanagri 0.01 – 2.86
Manthare et al., 2008Rahuri
56

57. Table: 21 Disease severity and percent loss in yield of rice
varieties/entries
Varieties/ entries Smutted balls (%) Disease severity Total loss in yield
(%)
Madhukar 4.00 80.00 4.25
Samba Mahsuri 3.64 182.00 16.65
Sarju 52 2.86 47.68 5.00
Jal Lahiri 1.88 31.85 4.40
Jalmagna 2.20 31.90 6.38
PA 6444 8.00 480.00 20.00
Upadhyay and Singh, 2013U.P.
57

58. Table 22: Severity of false smut and losses in yield on 24 rice varieties
Varieties/
Genotypes
Smutted grains
(%)
Disease severity
(%)
Grain weight of 10 panicles (g) Losses in grain
weight (%)
Un-smutted Smutted
PA 6444 3.74 182.36 42.65 27.70 17.09
Narendra 39 2.04 20.70 34.21 26.57 2.46
Sarju-52 2.21 71.86 44.56 31.78 9.32
PHB-71 2.37 58.27 40.55 27.32 8.02
PR 116 3.68 97.55 31.54 17.13 11.73
Pant Dhan 19 2.02 33.10 41.25 34.98 2.49
Pant Sankar
Dhan 3
4.76 156.17 42.34 29.58 9.88
Type 3 0.67 3.35 21.82 18.22 0.82
PSD 15 2.39 28.27 25.88 18.52 3.18
Sarbati 1.77 22.62 27.50 22.46 2.34
Pant Dhan 4 3.53 101.87 40.38 26.85 9.05
Pant Dhan 18 3.89 107.44 39.97 24.05 11.0
Cont.58

59. Jaya 1.81 27.83 36.42 30.24 2.60
PRH 10 2.30 66.56 38.25 24.28 10.56
Im. Pusa Basanti-
1
1.07 6.71 28.54 20.85 5.44
Pusa 1121 2.63 53.17 28.47 17.49 7.79
Pusa 1460 1.54 19.08 24.53 19.34 2.62
IR 24 0.84 10.92 35.03 27.66 2.73
Sugandh 1.12 14.04 31.69 26.58 2.41
Pusa Basmati-1 1.11 14.85 39.67 30.54 3.07
CD (5%) 0.81
SEM+ 0.28
CV 22.37
Pant Dhan 10 3.00 70.65 38.50 27.21 5.68
Basmati 370 1.13 9.51 23.21 18.74 1.62
Basmati 386 1.54 29.32 15.33 11.76 4.43
BPT 5204 1.45 22.35 42.61 37.63 1.33
Snehlata and Kumar (2015)Pantnagar 59

60. Conclusion
False smut occurs worldwide. Earlier, it is considered as minor
disease but since last decade it became a most devastating grain
disease of rice crop. Sclerotia are major perpetuating components.
Ascospores causing primary infection, whereas chlamydospores and
conidia cause secondary spread. False smut is favoured by application
of high nitrogenous fertilizers, high relative humidity and cloudy days
during flowering stage. FS is effectively managed by following
integrated approaches such as cultural practices, fertilizer
management, use of resistant varieties and application of effective
fungicides at 50 per cent panicle emergence stage of crop.
60

61. Future thrust
• Development of a more rapid and effective
system to evaluate rice resistant
germplasms that can effectively control
false smut disease.
• The host range and possible colonizing
organs by the fungus needs to be studied.
• Effective Forecasting is needed.
• To develop sound integrated approaches
for the management of false smut.
61