Use of Herbicides in Sequence for Control of Weeds in Maize

my seminar on Use of Herbicides in Sequence for
Control of Weeds in Maize
by

2. Seminar
On
Use of Herbicides in Sequence for
Control of Weeds in Maize
UMESHA, C
PAL(S)2013
Sr. M.Sc.(Agri.)

3. Sequence of presentation
Introduction
Meaning and Principle for sequential application
Importance of sequential application of herbicides
Effect of Sequential application of herbicides
Conclusion
Future line of work

4. INTRODUCTION

5. Maize(ZeamaysL.)orIndiancornisoneofthemostimportant
cerealsoftheworld.Apartfromdirecthumanconsumption,maize
grainsformanimportantingredientofpoultryandcattlefeed.
InIndia,maizeisgrownoveranareaof8.33millionhawithan
annualproductionof16.68milliontonnesandanaverage
productivityof2002kgha-
1
.
InKarnataka,maizeoccupiesanareaof1.07millionhawithan
annualproductionofabout3.03milliontonnesandanaverage
productivityof2833kgha-
1

6. Maize has 3 major unique characteristics
Itsmostobviously,maizelooksdifferenttothesmallgraincereals
likewheat,barleyandrice.
Commercialvarietiesofmaizeinmoretechnologicallyadvanced
farmingsystemsareactually‘hybrids’.
Maizeisphysiologicallydifferenttomanyothercropshaving
systemofphotosynthesiswhichiscalledC4,thismeansthatit
useslesswaterforagivenlevelofyield

7. Amongallweedcontrolmethodsculturalandmechanicalare
tediousandtimeconsumingbesideslabourintensiveandcostly.These
operationsaredifficulttocarryoutinthefield.
Useofpreandpost-emergentherbicideswouldmakethe
herbicidalweedcontrolmoreacceptabletofarmers,whichwillnot
changetheexistingagronomicpracticesbutwillallowforcomplete
controlofweeds.

8. Duetocontinoususeofpreemergentherbicidesincropsand
croppingsystem,theemergencepatternofweedshaschanged.
Thishasresultedindevelopmentofpostemergentherbicides.But
theeffortsmadetoevaluatetheefficacypreandpostemergent
herbicidesappliedinsequencelackinginmaize.

9. Amongallthepests(insects,animals,diseasesandweeds)in
India,weedsaloneareresponsibleforabout25%lossofcrop
production.
weedshavebeenrecognizedaspotentialpests,itsremovedby
culturally,mechanicallyandchemically.
Weedsreducecropyieldby31.5%
22.7%inwinter
36.5%insummer,kharifseasons

10. Impact of weeds on different crop ecosystems
Itisestimatedthatlossofagricultureproduction
mostdevelopedcountries-5%
lessdevelopedcountries-10%
leastdevelopedcountries-25%
Itisestimatedthatyieldlossby
weeds-45%
Insects-30%
Diseases-20%
otherpests-5%
Theworldfoodlossduetoweedswas287mtof11.5%oftotal
foodproduction.

11. Weed flora
Crop weed competition
Critical CWC

12. Weeds Common name Local name Family
A.Grassy weeds
CynodondactylonPers. Bermuda grass Garike, doobgrassPoaceae
Digitariamarginata Crabgrass - Poaceae
Dinebraretroflexa - Poaceae
EchinochloacolonumWatergrass Janglidan Poaceae
EleusineindicaL Goosegrass - Poaceae
Panicumspp. Panicum Barnyard grassPoaceae
Setariaitalica Banara,bani Poaceae
B. Sedges
CyperusrotundusL. Nut sedge Jeku, MothapurpleCyperaceae
Weedflorainmaize

13. Contd…..
C. Broad leaved weeds
Ageratum conyzoidesL Bill goat weed Mahkua Asteraceae
AmaranthusviriidsL Pigweed Junglichauli Amaranthaceae
AlternantherasessilisL. - - Amaranthaceae
ArgemonamexicanaL. Mexican poppy Barghar, satyanasiPapavaraceae
CommelinabenghalensisL. Dayflower, spider wort
Tropical
Insansia.Egali Commelinaceae
Cynotiscuculata Baghmula,jigali Commelinaceae
Corchorustrilocularis Tiliaceae
DigeraarvensisL. Lahasua Amaranthaceae
Euphorbia hirtaL. Garden spurge Bari dudhi Euphorbiaceae
Euphorbia prostrate - Euphorbiaceae
Euphorbia geniculata Chottidudhi Euphorbiaceae
PhyllanthusniruriL. Niruri Hezardena Euphorbiaceae
PortulacaoleraceaL. Purslane Kulfa Portulacaceae
PartheniumhysterophorusL. Carrot weed Congress Asteraceae
Physalisminima L. Ground cherry Ban makaya Solanaceae
TridaxprocumbensL. Tridax phulani Asteracea

14. Sl.
No
HerbicidesRecommended
dose
(kg a.i/ha)
Time of
application
Method of
application
Type of weed
control
1 Atrazine 1-1.5 PRE (0-3DAS)Soilapplied Control annual
weeds
2 Simazine 1-1.5 PRE (0-3DAS)Soil appliedControls annual
weeds
3 Pendimethalin 0.75-1 PRE Soil appliedLate emerging
annual weeds
commelinasp
4 2,4-D 1.0 POST
(3-4WAS)
Foliage
applied
Control Broad
leaved weeds
Different herbicides used in maize

15. 5 Alachlor 1.2-2.0 PRE
(0-3DAS)
Soilapplied Control most of the
annual grasses and
broad leaved weeds
6Paraquat
(Directed spray)
1.00 POST Foliage
applied
Controlall weeds
7Glyphosate
(Directed spray)
0.1 POST Foliage All type of weed
control
8Butachlor 1.00 PRE SoilappliedControl annual
weeds and BLW
Contd…..

16. PreplantSoilincorporationofEPTCat3-4Kg/ha,mixedwith
about0.5kg/haofeitherAtrazineorsimazineisaveryeffective
treatmentwillalsocontrolsedges.
Atrazineandsimazinewerefirsthighlysuccessfulpreemergence
Herbicidesinmaizewhichreplacedtheearlierusedherbicides2,4-
DandMCPAin1960.
Maizeshowshightolerancetotriazinegroupupto5-6kg/hain
commonly1-2kg/hacanbeusedtoavoidphytotoxicresidue
hazardsoftheseherbicides.

17. Indryareasatraziineandsimazineshouldbeslightlyincorporated
intosoiltoimproveherbicideefficacy.
Alachlorandbutachloraremosteffectivepreemergence
herbicidesagainsttheannualgrassesthansimazineandatrazinebut
theyweakagainstthebroadleafsthereforejudiciouscombination
oftwogroupsofherbicidesshouldcontrolbothtypesofweeds
effectively.
Linuronisreportedeffectivealsoagainstc.dactylon,
Pendimethalin(1kg/ha)hasbeennewlyaddedtothelistofpre
emergenceherbicidesinmaize.

18. Forearlypostemergencecontrolofyoungweedsinmaizea
verygoodherbicdecombinationis0.5kgalachlor+0.25kg
atrazine+5%phytoblandoilemulsionspray.
Combinationofpropalachlorandlinuronispreferredover
alachlorandmetalachlor.Laterat3-6leafofweedscyanazine
(0.75kg/ha)canbeusedonevenstillolderweeds.

19. Merits and demerits of PRE emergence herbicides
Merits:
Can be applied while planting /sowing
With adequate rain, provides control through first 4 weeks
Reduces late emerging weeds impact in maize
Low annual grass populations
Low to moderate population of annual BLW,Amaranths viridis.
Demerits:
Dependence on adequate rain within narrow period of time
Not effective on difficult BLW, perennial and high grass populations
Moderate to highgrass populations
Biennial and perennial weeds.

20. Merits and demerits of POST emergence herbicides
Merits
Controls late emerging weeds.
Consistent control of low to moderate annual weed populations
Demerits
Narrowwindowapplication,careshouldbetakenappliedat
particularstage.
Moderatetohighpopulationsofgrasses

21. It is application of herbicide one after the otheri.e. pre-
plant followed by pre emergence/Pre emergence followed by
Post emergence application.
Ex: Application of Atrazine as Pre-emergence followed by 2,4-D as
Postemergence.
Meaning of sequential application of herbicides

22. Importance of Sequential application
Providesenoughweedcontroltopreventmajorweed
problemsinmaize.
Moreconsistentweedcontroloflateemergingweeds
Greatercontrolandbiomassreductionsallowgreater
maizeyield
MoreconsistentweedcontrolinSEQthanPREor
Postalone

23. Principles
Tocontrolbroadspectrum/lateemergingweeds
Tocontrolweedflorathroughoutthegrowingseason
Difficultyininter-cultureoperationsduetounfavorableweather
PreemergencealoneandPostemergencealoneare
notmucheffective.

24. Research studies

25. Treatments Cyperus
esculentus
Convolvulu
s arvensis
Chenopodium
album
Amarantus
spp
Foramsulfuron26.94 71.47 91.20 100
Nicosulfuron55.63 74.42 100 93.80
Atrazin+lasso27.92 36.70 84.88 56.01
Weedy 0 0 0 0
Table-1-Weed control (percent) with herbicides
NURAKY et al, 2011

26. Treatments Cyperus
esculentus
Convolvulu
s arvensis
Chenopodium
album
Amarantus
spp
Foramsulfuron1.56 1.28 0 0
Nicosulfuron1.25 0 0 0
Atrazin+lasso3 1.41 0 0
Weedy 9.48 2.31 9.25 6.91
Table 2-weed density (number) at 26 days after sowing
NURAKY et al, 2011

27. Treatment
Plant height at
maturity (cm)
Ear height
aboveground (cm)
Leaf area index
No. of
leaves/plant (at
maturity)
Atrazine
Trazine
Callitraz
125.0
130.2
49.0
46.8
1.160
1.123
13.5
12.2
2,4-D
Calliherbe
Bextra
121.8
135.7 0
47.8
51.4
0.980
1.41
12.1
13.1
Glyphosate
Kalach 360L
Fire
Weed Out
120.1
143.6
128.5
66.3
56.7
48.5
1.110
1.490
1.343
12.7
13.4
13.7
Paraquat
Benaxone
Gramoxone Super
140.5
126.1
59.9
48.6
1.07
1.0133
13.1
12.8
Control (No herbicide)
LSD (P = 0.05)
126. 6
NS
44.8
NS
0.935
NS
13.2
NS
Table 3. Maize plant heights, height of ear above ground, leaf area
index number of leaves per plant measured at 10 WAP.
Ghana. Larbi,2013

28. Treatments
Weed index
(%)
WCE (%)Grainyield
(kg/ha)
1.Atrazine 1.25 kg/ha +1 IC at 30DAS 24.75 75.37 5297
2.Atrazine 1.25 kg/ha fbAtrazine 0.50 kg/ha 16.53 84.85 5876
3.Atrazine 1.25 kg/ha fbAtrazine 1.00 kg/ha 10.86 88.32 6275
4.Butachlor 1.00kg/ha + 1 IC at 30DAS 30.42 74.47 4898
5.Butachlor 1.00kg/ha fbAtrazine 0.50 kg/ha 17.37 83.40 5817
6.Butachlor 1.00kg/ha fbAtrazine 0.50 kg/ha 14.84 85.18 6020
7.Atrazine 1.25 kg/ha fb2,4-D 0.5 kg/ha 8.52 91.58 6440
8.Butachlor 1.00kg/ha fb2,4-D 0.5 kg/ha 10.22 89.72 6320
9.Farmers practice (1 IC at 20 and at 1 HW30 DAS)20.69 76.75 5583
10.Weed free check 0.00 94.67 7040
11.Weedy check 40.4 0.00 4195
SEm± 3.80 2.84 285
CD(0.05) 11.27 8.40 841
Table 4: WCE, WI and grain yield at different growth stages as influenced by
sequential application
ARS, Devihosur
Mallikarjun, 2008

29. Treatments
Plant height
(cm)
LAI Net
returns
(Rs ha
-1
)
B: C
ratio
T1: Atrazine1.25 kg/ha +1 IC at 30DAS 180.52 1.82 19602 2.27
T2: Atrazine1.25 kg/ha fbAtrazine0.50 kg/ha 185.55 2.21 22991 2.45
T3: Atrazine1.25 kg/ha fbAtrazine1.00 kg/ha 190.76 2.37 25130 2.55
T4: Butachlor1.00kg/ha + 1 IC at 30DAS 179. 16 1.75 17526 2.17
T5: Butachlor1.00kg/ha fbAtrazine0.50 kg/ha 182.78 2.07 23005 2.48
T6: Butachlor1.00kg/ha fbAtrazine0.50 kg/ha 186.34 2.29 23962 2.52
T7: Atrazine1.25 kg/ha fb2,4-D 0.5 kg/ha 193.38 2.54 26601 2.67
T8: Butachlor1.00kg/ha fb2,4-D 0.5 kg/ha 191.48 2.46 26224 2.70
T9: Farmers practice (1 IC at 20 and at 1 HW30
DAS)
181.76 1.96 21082 2.33
T10: Weed free check 196.46 2.69 27821 2.50
T11: Weedy check 173.32 1.70 14046 2.01
CDat 5% 8.68 0.41 3903 0.26
Mallikarjun, 2008 ARS, Devihosur
Table 5 : Effect of weed control treatments on growth parameters and economics as
influenced by sequential application

30. Treatment
Weed count
(per 0.5 m
2
)
Weed dry
weight (per
0.5 m
2
)
Weed control
index (%)
TDMP at harvest
of maize (g/plant)
T
1: Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine
1.50 kg a.i./ha (POST)
4.43 3.87 75.9 292
T
2: Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine
1.75 kg a.i./ha (POST)
4.33 4.47 67.4 327
T
3: Atrazine 1.25 kg a.i./ha (PRE) fb. Paraquat
1.0 kg a.i./ha (POST)
3.93 3.10 84.8 304
T
4: Atrazine 1.25 kg a.i./ha (PRE) fb. Paraquat
1.5 kg a.i./ha (POST)
4.10 3.40 81.5 317
T
5: Atrazine 1.25 kg a.i./ha (PRE) fb. Glyphosate
2.5 kg a.i./ha (POST)
3.08 3.29 82.7 332
T
6: Atrazine 1.25 kg a.i./ha (PRE) fb. Glyphosate
3.0 kg a.i./ha (POST)
3.43 3.36 82.0 284
T
7: Atrazine 1.25 kg a.i./ha (PRE) fb. 2,4-D Na
salt 2.0 kg a.i./ha (POST)
4.10 3.84 76.2 277
T
8: Atrazine 1.25 kg a.i./ha (PRE) fb. 2,4-D Na
salt 3.0 kg a.i./ha (POST)
3.89 3.91 75.3 292
T
9: Atrazine 1.25 kg a.i./ha (PRE) fb. (2 IC @ 30
and 45 DAS) + 1 HW (between 30 and 45
DAS)
3.29 3.70 77.5 310
T
10: Weedy check 6.23 7.78 0 298
SEm+ 0.2 0.0 0.53 3.26
CD at 5% 0.6 0.1 1.56 9.68
Ishrat, 2010
Table 6 : Weed dynamics as influenced by pre and post emergence application of
herbicides in maize
Ramdurg

31. Treatment
100-seed
weight (g)
Grain yield
(kg/ha)
Net income
(Rs./ha)
B:C
T
1: Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine 1.50
kg a.i./ha (POST)
36.5 4637 51802 3.48
T
2: Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine 1.75
kg a.i./ha (POST)
38.8 4534 50822 3.41
T
3: Atrazine 1.25 kg a.i./ha (PRE) fb. Paraquat 1.0 kg
a.i./ha (POST)
32.8 4791 54725 3.56
T
4: Atrazine 1.25 kg a.i./ha (PRE) fb. Paraquat 1.5 kg
a.i./ha (POST)
37.6 4752 52488 3.38
T
5: Atrazine 1.25 kg a.i./ha (PRE) fb. Glyphosate 2.5
kg a.i./ha (POST)
43.6 5305 59139 3.70
T
6: Atrazine 1.25 kg a.i./ha (PRE) fb. Glyphosate 3.0
kg a.i./ha (POST)
35.7 5283 60702 3.76
T
7: Atrazine 1.25 kg a.i./ha (PRE) fb. 2,4-D Na salt
2.0 kg a.i./ha (POST)
34.7 3457 39411 2.90
T
8: Atrazine 1.25 kg a.i./ha (PRE) fb. 2,4-D Na salt
3.0 kg a.i./ha (POST)
38.5 4105 41853
T
9: Atrazine 1.25 kg a.i./ha (PRE) fb. (2IC 30 and 40
DAS) + 1 HW (between 30 and 45 DAS)
40.2 4826 52375 3.25
T
10: Weedy check 30.7 2342 20727 2.23
SEm+ 0.9 1.91 2509 0.12
CD at 5% 2.67 567 7454 0.36
Ramdurg Ishrat, 2010
Table 7 : Yield attributes and economics as influenced by pre and post emergence application
of herbicides in maize

32. Table 8 : weed index, WCE and Grain yield of maize as influenced by
application of herbicides in maize
Treatment Weed
index (%)
WCE
(%)
Grain yield
(t/ha)
T1:Weedycheck(noweeding,nointercultivation) 33.25 0.00 5.13
T2:Mechanicalweeding(at25DASandat45DASandICat30
DAS)
9.96 27.94 6.94
T3:Atrazine(1.00kgha
—1
pre-em)+ICat30DAS 18.09 16.05 6.31
T4:Atrazine(1.25kgha
—1
pre-em)+ICat30DAS 16.00 18.36 6.49
T5:Atrazine(0.75kgha
—1
pre-em)fb.2,4-D(1.00kgha--1
post-em)at30DAS
1.78 28.58 7.57
T6:Oxyfluorfen(0.25kgha
—1
post–em)at20DAS
29.37 24.45 5.45
T7:Weedfreecheck(ICat20DASand40DAS+HWat30DAS
and50DAS)
0.00 36.18 7.72
S.Em± 3.79 0.94 0.29
CD at 5% 11.26 2.79 0.87
MARS, Dharwad Shantveerayya, 2010

33. Treatments Gross
returns
(Rs.ha
-1
)
Net returns
(Rs.ha
-1
)
Benefit:
cost ratio
T1:Weedycheck(noweeding,nointercultivation) 69564 42670 2.59
T2:Mechanicalweeding(at25DASandat45DASandIC
at30DAS)
94156 64510 3.18
T3:Atrazine(1.00kgha--1
pre-em)+ICat30DAS
85562 56235 2.92
T4:Atrazine(1.25kgha--1
pre-em)+ICat30DAS
88048 58371 2.97
T5:Atrazine(0.75kgha--1
pre-em)fb.2,4-D(1.00kgha--1
post-em)at30DAS
102600 72993 3.47
T6:Oxyfluorfen(0.25kgha--1
post–em)at20DAS
73899 44726 2.53
T7:Weedfreecheck(ICat20DASand40DAS+HWat
30DASand50DAS)
104684 73785 3.39
S.Em± 3985.49 3985.49 0.14
CD at 5% 11841.49 11841.49 0.42
Table 9 : Economics of maize as influenced by application of herbicides
MARS, Dharwad Shantveerayya, 2010

34. Treatments
Total dry weight of
weeds (g m
-2
)
Weed index
Weed control
efficiency (%)
1.Atrazine 1.00 kg a.i./ha (PRE) 6.69 13.20 50.15
2.Metribuzine 0.25 kg a.i./ha (PRE) 6.71 14.91 50.00
3.Alachlor 0.50 kg a.i./ha + Atrazine 1.0 kg a.i./ha
(PRE)
6.36 11.74 52.62
4.Glyphosate 1.00 kg a.i./ha (PP) fb. Atrazine 375 g
a.i./ha + Alachlor 0.50 kg a.i/ha
8.55 24.01 36.33
5.Glyphosate 1.00 kg a.i./ha (PP) fb. 2, 4-D @ 2.00 kg
a.i./ha (POST)
7.54 19.75 43.83
6.Glyphosate 1.00 kg a.i./ha (PP) + Castor oil 4. ltr/ha 8.18 30.83 39.05
7.Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine1.50 kg
a.i./ha (PRE) to weeds
6.03 3.80 55.07
8.Atrazine 1.00 kg a.i./ha fb. 2, 4-D @ 2.0 kg a.i./ha 6.64 12.68 50.52
9.Alachlor 1.00 kg a.i./ha (PRE) fb. Oxyfluorfen 0.20
kg a.i./ha (POSt) directed spray
5.15 12.79 61.62
10.Atrazine 1.50 kg a.i./ha 6.69 13.51 50.15
11.Oxyfluorfen 0.15 kg a.i./ha (PRE) 5.64 22.32 57.96
12.Maize + cover crop (cowpea) 5.97 31.42 55.50
13.Maize + cover cropp(mungbean) 6.55 25.39 51.19
14.Weed free check 1.25 - 90.73
15.Weedy check 13.42 49.73 -
S.Em+ 0.44
CD at 5% 1.27
Table10 : Total dry weight, weed control efficiency and weed index in maize as influence by weed control treatment
Shailendra singh, 2011
ARS, Arabhavi

35. Treatments
Grain weight
per plant (g)
Grain yieldStover yield
Atrazine 1.00 kg a.i./ha (PRE) 102.97 48.99 70.94
Metribuzine 0.25 kg a.i./ha (PRE) 106.00 47.85 72.81
Alachlor 0.50 kg a.i./ha + Atrazine 1.0 kg a.i./ha (PRE) 108.40 49.12 69.38
Glyphosate 1.00 kg a.i./ha (PP) fb. Atrazine 375 g a.i./ha +
Alachlor 0.50 kg a.i/ha
96.67 42.35 57.40
Glyphosate 1.00 kg a.i./ha (PP) fb. 2, 4-D @ 2.00 kg a.i./ha
(POST)
96.70 44.92 62.81
Glyphosate 1.00 kg a.i./ha (PP) + Castor oil 4. ltr/ha 85.87 38.54 58.44
Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine1.50 kg a.i./ha
(PRE) to weeds
110.17 54.02 74.06
Atrazine 1.00 kg a.i./ha fb. 2, 4-D @ 2.0 kg a.i./ha 105.20 48.91 68.13
Alachlor 1.00 kg a.i./ha (PRE) fb. Oxyfluorfen 0.20 kg a.i./ha
(POSt) directed spray
106.50 48.86 68.44
Atrazine 1.50 kg a.i./ha 103.90 48.41 68.44
Oxyfluorfen 0.15 kg a.i./ha (PRE) 97.17 43.16 58.96
Maize + cover crop (cowpea) 84.63 38.34 48.75
Maize + cover cropp (mung bean) 91.80 41.59 60.63
Weed free check 117.67 56.01 76.25
Weedy check 83.67 28.11 45.31
S.Em+ 5.22 3.16 2.67
CD at 5% 15.11 9.17 7.73
Table 11: Grain yield and yield components of maize as influenced by weed control treatments
Shailendra singh, 2011ARS Arabhavi

36. Conclusion
Sequentialapplicationofherbicideshelpstocontrol
weedsontimeandforlongerperiod.Pre-emergenceapplicationof
atrazine1.50kgha
-1
/simazine1-1.5kgha
-1
helpstocontrolweeds
upto30daysfollowedbyatrazine1.50kgha
-1
(pre-emergenceto
weedandpostemergencetocrop)/2,4-D@1kgha
-1
/paraquat1kg
ha
-1
(Directedspray)/glyphosate0.1kgha
-1
(Directedspray)control
afterthenewemergingweeds.Thiswillhelpthefarmerinreducing
theburdenoflabourproblem.

37. FUTURE LINE OF WORK
Continuousstudiesarerequiredontheeffectivenessandbio-
efficacyofnewgenerationherbicidesandherbicidemixturesin
maizecrop.
Studiesonresidualeffectofherbicidesoncropgrowninsequence
andalsoontheenvironmentinlong-runneedstobeinitiated.
Thestudiesareneededontheuseofherbicideingranularform.
Useofdifferentnewmethodsofweedcontrollikeelectromagnetic
radiations.
Useofencapsulatedherbicides.

38. “Knowledge is like a garden: if it is not cultivated, it
cannot be harvested”