TRANSPLANTED RICE WEED MANAGEMENT

1. Weed management in
transplanted PADDY
PRESENTED BY
M.SHRAVAN KUMAR REDDY
M.Sc.AGRONOMY 1st YEAR
RAM/16-03.

2. Weeds in rice
• Weed : weed is an unwanted plant.
• Grasses are dominant in irrigated/transplanted
systems
• Sedges are dominant in rainfed system.
• Weed problems are more severe in aerobic&
Direct seeded rice when compared with
irrigated rice.
• Nearly 134 weed species identified from rice
field belongs to 32 taxonomic families.

3. Weeds in transplanted rice
• Grasses : Echinocloa colona , Echinocloa crus-galli,
cyanotis axillaris , Monochoria vaginalis, caesulia
axillaris .
• Sedges: Cyperus iria , Cyperus difformis,
Fimbristylis miliacea , Scirpus maritimus
,Fimbristylis littoralis.
• Broad leaved weeds :Marsilea quadrifoliata, Ludwigia
octovalis , Ludwigia paviflora ,
Oxalis corniculata ,Ammania baccifera ,
Ipomea aquatica ,Eclipta alba ,Rungia repens
,Sphenoclea zeylanica ,Lippia nodiflora etc….

4. Critical period for weed control
• Weed competition do not occur during the
entire cropping period. Control of weeds in
the critical period of competition is important
• Usually it commences around 2 weeks after
transplanting and may continue up to 5-8
weeks. Hence early weeding is important to
reduce yield losses.

5. Echinocloa crusgalli Echinocloa colonum
Ischemum rugosum
Grasses

6. • Echinocloa colona • Echinocloa crusgalli

7. Cyanotis axillaris

8. Fimbristylis milleaceaCyperus difformis
Cyperus rotundus Cyperus iria
Scirpus spp
Sedges

9. Cyperus difformis
Cyperus iria

10. Eclipta alba
Ammania bacciferaLudwigia ascendens
Broad leaved weeds

11. Phyla nodiflora
Marselia quadrifolia

14. Control of Weeds using IWM Practices
• weeds are most efficiently and economically controlled by
the simultaneous application of a variety of practices.
• These practices including preventive, cultural, manual,
mechanical, biological and chemical.
• Integrated weed Management practices (IWM) combines
these different practices.
• If any single control method is used for a along time,
weed species resistant to that method may build up and
eventually the control measure will fail.
• So, the objective of IWM is to create conditions
unfavorable to weeds while maintaining suitable
condition for crop.

15. Diff b/w prevention ,,eradication and
control ???
• Prevention : Means measures taken to
prevent or arrest the introduction and spread
of weeds
• Eradication : It is complete removal of all live
plant parts and seeds of the weed from an
area ..
• Control : weed infestations are reduced but
not necessarily eliminated..

16. Preventive Control Measures
• Use clean seeds
• Keep seed bed weed free
• Keep bunds and irrigation canal clean
• Keep tools and machinery clean
• Keep livestock out of field
• Prevent weeds from seedlings

17. Cultural Control Measures
Summer ploughing ,,
cultivation of irrigated dry crops during post-rainy
periods reduces the weed infestation.
Proper land preparation
Cultural practices like dual cropping of rice-azolla,
and rice-green manure reduces the weed
infestation to a greater extent.
 Cultivar selection
Crop establishment
Water management
Control of fertilizer application

18. • Mechanical Control Measures: not much
followed in transplanted paddy because in many areas
farmes following random transplanting …so it is not
suitable much
• But in case of line sown conditions and in SRI
method it is recommended
• Use of rotary weeder from 15 DAT at 10 days
interval. It saves labour for weeding, aerates the soil and
root zone, prolongs the root activity, and improves the
grain filling though efficient translocation and ultimately
the grain yield.

19. • Manual Weed Control: Hand weeding.
• Biological Control Method:
• Weed utilization in rice fields, Using mulching
effect and Allopathic effect

20. Hand weeding

21. General mistakes doing by farmers
• Improper usage of dosages
• Improper mixing with sand
• Wrong use of chemicals
• Wrong maintainance of water etc..,,
• Usage of herbicide applied sprayer for
insecticide or fungicide application without
proper cleaning etc..

22. Things to be kept in mind while
recommending herbicides
• Stage of crop
• Stage of weed
• Trade name and accurate dosage of the
herbicide
• Climatic conditions $ management

23. Name of the herbicide Herbicide group Mode of action
Fenoxaprop-P-ethyl Aryloxyphenoxy-propionate
‘FOPs’
Inhibition of acetyl CoA
carboxylase (ACCase)
Bensulfuron-methyl
Chlorimuron-ethyl
Ethoxysulfuron
Azimsulfuron
Halosulfuron-methyl
Metsulfuron-methyl
Pyrazosulfuron-ethyl
Sulfonylurea Inhibition of acetolactate
synthase ALS
(acetohydroxyacid synthase
AHAS)
Penoxsulam Triazolopyrimidine ALS inhibitor
Bispyribac-Na Pyrimidinyl(thio)benzoate ALS inhibitor
Carfentrazone-ethyl Triazolinone Inhibition of
protoporphyrinogen enzyme
Herbicides used in TPR and their mode of action

24. Chemical Weed management in
T. RICE
• NURSERY MANAGEMENT :
• 1 . Dry nursery : more problem ,,and
maintanance of moisture at the time of
application is imp..
• 2. Wet nursery : compared to dry nursery less
,,and
Manual weeding is less efficient in nursery weed
management ,,
Mechanical also not possible under broad casted
conditions ,,but proves useful under line sowing
conditions

25. Chemical contol of weeds
• Nursery weed management :Apply
Butachlore @ 1 to 1.5 kg/ ha at 3 to 5 DAS or
Pretilachlore + safener @ 0.4 to 0.5 kg /ha at 3
to 5 DAS or
• Pendimethalin @ 1.0 to 1.5 kg /ha at 3 to 5 DAS
or
• Pyrazosulfuron ethyl @ 0.015 to 0.020 kg/ha
apply any one of the above chemicals.Or
• Bispyribac sodium @ 0.5 ml /litre of water at 9
to 10 DAS .. Or
• Apply cyhalopof p butyl @ 0.19 to 0.28 kg/ha if
there is infestation of grassy weeds especially
Echinocloa.

26. Transplanted rice:
• Butachlore @ 1 to 1.5 kg /ha OR benthiocarb @ 1 to 1.5 kg
/ha or pendimethalin @ 1 to 1.5 kg/ha at 3 to 5 DAT or
• pretilachlore 0.4 to 0. 5kg/ha …if use safener then the dose is
0.75 kg/ha at 3 to 5 DAT
• Propanil @ 2 to 3 kg /ha at 15 DAT …very useful againest
grasses especially echinocloa or
• Met sulfuron methyl ( 10%)+ chlorimuron ethyl ( 10%) + 0.2 %
surfactant @ 4 g/ha 25 to 30 DAT or
• Ben sulfuron methyl @ 50 to 60 g /ha AT 30 DAT or
• 2,4-D Ethyl ester @ 0.75 to 1 kg /ha at 25 DAT for BLW or
• Pyrazosulfuron ethyl@ 0.015 to 0.020 kg /ha as pre emergence
or early post emergence at 10 to 15 DAT …

27. • Anilophos @ 0.40 to 0.43 kg/ha .it control many
grasses
• Alachlore @ 1 to 2 kg /ha as preplant emergence
3 to 5 DAT is quite effective . However this may
be followed by a hand weeding later or post
emergence application of propanil for controlling
BLW in transplanted rice
• Fluchloralin @ 1 kg /ha as pre transplanting
treatment on puddled soil or Butachlore 1 to 1.5
kg /ha or pendimethalin @ 1 to 1.5 kg /ha as pre
emergence immediately after transplanting
followed by 2, 4 –D @ 0.5 kg/ha at 30 35 DAT will
give a good control broad spectrum of weeds .

28. • Bentazon @1-2 kg /ha as post emergence at
almost all stages of rice plants in transplanted
rice to control BLW.
• Metsulfuron methyl @ 4 to 8 g/ha as post
emergence at 30 to 35 DAS or DAT for
controlling BLW.

29. Algae control in transplanted rice
• Copper sulphate or COC @ 10 kg/ha ..
• Nitrofen is also effective
• However ,if there are beneficial blue green
algae living together with undesired ones,,it is
better that don’t apply any herbicide

30. Spraying of herbicides .

31. Recommended IWM practices for
transplanted rice
 Good crop husbandary + Residue
incorporation + clean seeding + pre
emergence herbicide + hand weeding at 30 to
35 DAT
 Good crop husbandary + Green manuring +
clean seeding + pre emergence herbicide +
hand weeding at 30 to 35 DAT
 Good crop husbandary + pre emergence
herbicide + hand weeding at 30 to 35 DAT

32.  Good crop husbandary + Residue incorporation
/green manuring + clean seeding + high density
planting or skip row planting + pre emergence
herbicide + fish cultivation
 Good crop husbandary + hand weeding at 15 to 20
DAT + post emergence herbicide at 30 35 DAT
 Good crop husbandary + pre emergence herbicide +
shallow depth of water + hand weeding at 30 to 35
DAT .
 Good crop husbandary + shallow depth of water +
post emergence herbicide at 30 35 DAT ..

43. Table 23: Effect of herbicide treatments on total weed count and dry weight in
transplanted rice
Treatments Dose
(g/ha)
Total weed count (No./m2) Total weed dry weight (g/m2)
60 DAT At harvest 60 DAT At harvest
2010 2011 2010 2011 2010 2011 2010 2011
Bispyribac sodium (20g/ha) 20 5.0 4.7 6.6 6.2 1.9 3.8 2.9 5.4
Bispyribac –
sodium(25g/ha)
25 4.5 3.5 6.2 5.3 1.7 2.8 2.5 4.6
Bispyribac –
sodium(30g/ha)
30 4.9 2.7 5.0 4.7 1.9 2.2 2.0 4.1
Cyhalofop-butyl fb 2,4-
D(90g/ha,1.0kg/ha)
90 fb1000 6.4 4.9 5.9 8.0 2.2 3.4 2.3 5.6
Cyhalofop-butyl fb
metsulfuron -methyl
(90g/ha,4g/ha)
90 fb 4 6.4 4.8 5.1 8.5 3.0 4.1 1.8 5.6
Butachlor fb 2,4-
D(1.5kg/ha,1.0kg/ha)
1500 fb
1000
7.1 5.3 5.5 6.5 2.8 4.3 2.2 5.4
Butachlor fb metsulfuron –
methyl
1500 fb 4 6.5 4.7 4.9 8.6 2.4 4.6 1.9 5.5
Farmers practice 2.8 5.9 6.2 7.4 1.0 4.5 1.9 5.5
Unweeded check 9.2 8.5 10.1 10.8 4.5 7.0 4.6 8.9
LSD (P=0.05) 2.2 2.0 1.7 1.5 1.0 1.6 0.8 1.3
Kumar et al ., 2013Himachal pradesh

44. Table 24: Effect of different herbicides treatments on weeds in transplanted rice
Treatment Dose
(g a.i /ha)
WD
(No./m2)
WDM
(g/m2)
WCE
(%)
WI
(%)
Flucetosulfuron 20 3.99 3.48 77.93 19.71
Flucetosulfuron 25 3.62 2.95 82.89 9.99
Penoxsulam +Cyhalofop butyl 120 3.57 2.94 83.76 12.76
Penoxsulam +Cyhalofop butyl 135 4.18 3.55 84.46 20.70
Bispyribac – sodium 35 3.80 3.21 82.06 19.29
Anilofos 500 4.34 3.86 78.05 18.60
Two handweeding @ 20 & 40
(DAT)
- 3.06 2.50 94.44 4.21
Weed free - 0.00 0.00 100 0
Weedy check - 4.89 4.50 0 62.26
C.D.(P=0.05) - 0.29 0.40 - -
Bhimwal and Pandey ,2015Uttarakhand

46. Table 14 : Effect of crop establishment methods and weed management
practices on weeds and economics of rice.
Treatment WCE (%) Net return
(Rs./ha)
B:C ratio
Methods of establishment (MainPlots)
M1-Manual line transplanting 74.36 24664 1.82
M2-Mechanical line transplanting 74.68 19633 1.53
M3-Direct planting system (DPS) 78.23 32450 2.16
M4-Drum seeded rice (Sprouted seeds) 74.38 19301 1.73
Weed management practices (SubPlots)
S1-PE PSE 30 g/ha @ , PoE Almix 4 g/ha 73.52 24544 1.89
S2-PE PSE 30 g/ha ,PoE
Bispyribac Na 4 g /ha
78.48 30556 2.06
S3-PE Londax power 10 kg /ha ,PoE Almix 4g/ha 68.52 20582 1.71
S4-PE Londax power 10 kg /ha ,
PoE Bispyribac Na 4 g /ha
75.64 25460 1.84
S5- 2 HW @ 20 & 40 DAT/DAS 80.91 29437 1.84
S6-Unweeded control - 13491 1.52
Revathi and Annadurai, 2014Kerala

47. Table 15: Effect of crop establishment methods and weed management practices
on weeds and economics in rice
Treatment WD
(No./m2)
WDM
(kg/ha)
GR (× 103
Rs /ha)
NR (×103
Rs/ha)
Crop establishment methods (MainPlots)
C1-Conventional planting 9.9 11.6 60.13 57.23
C2-SRI marker planting 7.3 9.6 58.11 55.09
C3- SRI machine planting 6.0 7.6 26.74 26.74
C.D(P= 0.05) 1.2 2.1
Weed management (SubPlots)
W1- CW (4) 3.1 6.6 81.662 44.52
W2-PE Pretilachlor at 0.75 kg /ha+ 2 CW 10.7 10.5 107.33 75.34
W3-PE Pretilachlor at 0.75 kg /ha
+ EPOE Bispyribac @ 20 g/ha
4.6 8.3 116.46 87.51
W4-PE Pretilachlor at 0.75 kg /ha +
EPoE Bispyribac @ 20 g/ha +CW
3.9 7.4 61.82 59.42
W5-EPoE Londax power @ 0.66 kg/ha + 2 CW 6.7 7.6 53.16 50.00
W6-Unweeded control 17.3 17.5 45.54 43.15
C.D(P= 0.05) 1.4 1.2
Sangeetha et al ., 2015Coimbatore

48. Table 19: Effect of N scheduling, weed management and rice establishment on
weeds and yield of rice
Treatments WDM (g/m2) WI (%) GY (t/ha)
Rice establishment methods (Main plot)
Puddled transplanting 8.1 10.8 4.64
Unpuddled transplanting 9.4 19.9 4.20
C.D.(P=0.05) 0.38 - 0.17
Weed management (Sub plot)
Butachlor 1.5 kg/ha (PE) fb Azimsulfuron 35 g / ha 11.2 20.8 4.37
pretilachlor 0.75 kg/ha (PE) fb Azimsulfuron 35 g / ha 10.2 12.6 4.52
Butachlor 1.5 kg/ha fb conoweeding at 20 DAT 7.4 9.0 4.93
2 HW at 20 & 40 DAT 1.0 0.0 5.42
Weedy 13.8 43.5 2.85
C.D.(P=0.05) 0.62 - 0.28
Time of nitrogen application
½ N at basal, ¼ N at tillering stage, ¼ at PI stage 9.2 19.1 4.22
½ N at10 DAT, ¼ N at tillering stage, ¼ at PI stage 8.2 11.6 4.61
C.D.(P=0.05) 0.29 - 0.14
Sahu et al., 2015UP

49. Table 20: Microbial population affected by rice culture and weed control measures
at 35 DAS/DAT
Treatment Bacteria
(104 cfu /g)
Fungi
(101cfu /g)
Actinomycetes
(103cfu /g)
Method of rice culture (MainPlots)
Direct seeded 247.42 12.66 50.19
Transplanted 252.33 17.76 44.76
C.D.(P=0.05) 1.95 2.01 3.03
Weed control measure (SubPlots)
Penoxsulam @ 20 g at 10 DAS/DAT 243.67 13.83 42.00
Penoxsulam @ 25 g at 10 DAS/DAT 230.83 10.17 35.33
Penoxsulam @ 20 g at 15 DAS/DAT 234.50 12.50 39.83
Penoxsulam @ 25 g at 15 DAS/DAT 232.00 10.33 33.17
Pretilachlor @ 750 g/ha as PE 255.00 16.17 53.17
Weed free check 272.50 18.67 63.67
Weedy check 280.67 24.83 70.17
C.D.(<0.05) 4.85 1.63 3.71
Cfu-Colony forming units Khare et al ., 2014