use of herbicides in sequence for control of weeds in maize

Seminar

On Use of Herbicides in Sequence for

Control of Weeds in Maize

UMESHA, CPAL(S)2013Sr. M.Sc.(Agri.)

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

INTRODUCTION

Maize (Zea mays L.) or Indian corn is one of the most important cereals of the world. Apart from direct human consumption, maize grains form an important ingredient of poultry and cattle feed.

In India, maize is grown over an area of 8.33 million ha with an annual production of 16.68 million tonnes and an average productivity of 2002 kg ha-1.

In Karnataka, maize occupies an area of 1.07 million ha with an annual production of about 3.03 million tonnes and an average productivity of 2833 kg ha-1

Maize has 3 major unique characteristics

Its most obviously, maize looks different to the small grain cereals like wheat, barley and rice.

Commercial varieties of maize in more technologically advanced farming systems are actually ‘hybrids’.

Maize is physiologically different to many other crops having system of photosynthesis which is called C4, this means that it uses less water for a given level of yield

Among all weed control methods cultural and mechanical are tedious and time consuming besides labour intensive and costly. These operations are difficult to carryout in the field.

Use of pre and post-emergent herbicides would make the herbicidal weed control more acceptable to farmers, which will not change the existing agronomic practices but will allow for complete control of weeds.

Due to continous use of preemergent herbicides in crops and cropping system, the emergence pattern of weeds has changed.

This has resulted in development of post emergent herbicides. But the efforts made to evaluate the efficacy pre and postemergent herbicides applied in sequence lacking in maize.

Among all the pests(insects, animals, diseases and weeds) in India, weeds alone are responsible for about 25% loss of crop production.

weeds have been recognized as potential pests, its removed by culturally, mechanically and chemically.

Weeds reduce crop yield by 31.5%

22.7 % in winter

36.5% in summer, kharif seasons

Impact of weeds on different crop ecosystems It is estimated that loss of agriculture production

most developed countries- 5%

less developed countries- 10%

least developed countries- 25%

It is estimated that yield loss by

weeds - 45%

Insects - 30%

Diseases - 20%

other pests - 5%

The world food loss due to weeds was 287 mt of 11.5% of total food production.

Weeds Common name Local name Family

A. Grassy weeds

Cynodon dactylon Pers. Bermuda grass Garike, doob grass Poaceae

Digitaria marginata Crabgrass - Poaceae

Dinebra retroflexa - Poaceae

Echinochloa colonum Watergrass Jangli dan Poaceae

Eleusine indica L Goosegrass - Poaceae

Panicum spp. Panicum Barnyard grass Poaceae

Setaria italica Banara, bani Poaceae

B. Sedges

Cyperus rotundus L. Nut sedge Jeku, Motha purple Cyperaceae

Weed flora in maize

Contd…..C. Broad leaved weedsAgeratum conyzoides L Bill goat weed Mahkua Asteraceae

Amaranthus viriids L Pigweed Jungli chauli AmaranthaceaeAlternanthera sessilis L. - - AmaranthaceaeArgemona mexicana L. Mexican poppy Barghar, satyanasi Papavaraceae Commelina benghalensis L. Dayflower, spider wort

TropicalInsansia. Egali Commelinaceae

Cynotis cuculata Baghmula ,jigali Commelinaceae

Corchorus trilocularis Tiliaceae

Digera arvensis L. Lahasua AmaranthaceaeEuphorbia hirta L. Garden spurge Bari dudhi Euphorbiaceae Euphorbia prostrate - Euphorbiaceae

Euphorbia geniculata Chotti dudhi Euphorbiaceae

Phyllanthus niruri L. Niruri Hezar dena Euphorbiaceae

Portulaca oleracea L. Purslane Kulfa PortulacaceaeParthenium hysterophorus L. Carrot weed Congress Asteraceae

Physalis minima L. Ground cherry Ban makaya SolanaceaeTridax procumbens L. Tridax phulani Asteracea

Sl. Sl. NoNo

HerbicideHerbicidess

RecommenRecommended doseded dose

(kg a.i/ha)(kg a.i/ha)

Time of Time of applicatioapplicatio

nn

Method of Method of applicatioapplicatio

nn

Type of weed Type of weed controlcontrol

1 Atrazine 1-1.5 PRE (0-3DAS)

Soil applied

Control annual weeds

2 Simazine 1-1.5 PRE (0-3DAS)

Soil applied

Controls annual weeds

3 Pendimethalin

0.75-1 PRE Soil applied

Late emerging annual weeds commelina sp

44 2,4-D 1.0 POST(3-4WAS)

Foliage applied

Control Broad leaved weeds

Different herbicides used in maize

5 Alachlor 1.2-2.0 PRE (0-3DAS)

Soil applied

Control most of the annual grasses and broad leaved weeds

6 Paraquat (Directed spray)

1.00 POST Foliage applied

Control all weeds

7 Glyphosate (Directed spray)

0.1 POST Foliage All type of weed control

8 Butachlor 1.00 PRE Soil applied

Control annual weeds and BLW

Contd…..

Preplant Soil incorporation of EPTC at 3-4 Kg/ha, mixed with about 0.5kg/ha of either Atrazine or simazine is a very effective treatment will also control sedges.

Atrazine and simazine were first highly successful pre emergence Herbicides in maize which replaced the earlier used herbicides 2,4-D and MCPA in1960.

Maize shows high tolerance to triazine group upto 5-6kg/ha in commonly 1-2 kg/ha can be used to avoid phytotoxic residue hazards of these herbicides.

In dry areas atraziine and simazine should be slightly in corporated into soil to improve herbicide efficacy.

Alachlor and butachlor are most effective pre emergence herbicides against the annual grasses than simazine and atrazine but they weak against the broadleafs therefore judicious combination of two groups of herbicides should control both types of weeds effectively.

Linuron is reported effective also against c.dactylon, Pendimethalin(1kg/ha) has been newly added to the list of pre emergence herbicides in maize.

For early post emergence control of young weeds in maize a

very good herbicde combination is 0.5 kg alachlor +0.25 kg atrazine +5% phytobland oil emulsion spray.

Combination of propalachlor and linuron is preferred over

alachlor and metalachlor. Later at 3-6 leaf of weeds cyanazine (0.75kg/ha)can be used on even still older weeds .

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 high grass populations

Biennial and perennial weeds.

Merits and demerits of POST emergence herbicides

Merits Controls late emerging weeds.

Consistent control of low to moderate annual weed populations

Demerits

Narrow window application, care should be taken applied at

particular stage.

Moderate to high populations of grasses

It is application of herbicide one after the other i.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

Importance of Sequential application

Provides enough weed control to prevent major weed problems in maize.

More consistent weed control of late emerging weeds

Greater control and biomass reductions allow greater maize yield

More consistent weed control in SEQ than PRE or Post alone

Principles

To control broad spectrum / late emerging weeds

To control weed flora throughout the growing season

Difficulty in inter-culture operations due to unfavorable weather

Pre emergence alone and Post emergence alone are

not much effective.

Research studies

Treatments Cyperusesculentus

Convolvulus arvensis

Chenopodiumalbum

Amarantusspp

Foramsulfuron 26.94 71.47 91.20 100

Nicosulfuron 55.63 74.42 100 93.80

Atrazin+lasso 27.92 36.70 84.88 56.01

Weedy 0 0 0 0

Table-1- Weed control (percent) with herbicides

NURAKY et al, 2011

Treatments Cyperusesculentus

Convolvulus arvensis

Chenopodiumalbum

Amarantusspp

Foramsulfuron 1.56 1.28 0 0

Nicosulfuron 1.25 0 0 0

Atrazin+lasso 3 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

TreatmentPlant height at maturity (cm)

Ear height aboveground (cm)

Leaf area indexNo. of

leaves/plant (at maturity)

Atrazine Trazine Callitraz

125.0130.2

49.046.8

1.1601.123

13.512.2

2,4-DCalliherbeBextra

121.8135.7 0

47.851.4

0.9801.41

12.113.1

GlyphosateKalach 360LFireWeed Out

120.1143.6128.5

66.356.748.5

1.1101.4901.343

12.713.413.7

ParaquatBenaxoneGramoxone Super

140.5126.1

59.948.6

1.071.0133

13.112.8

Control (No herbicide)LSD (P = 0.05)

126. 6NS

44.8NS

0.935NS

13.2NS

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

Treatments Weed index

(%)WCE (%) Grain yield

(kg/ha)

1.Atrazine 1.25 kg/ha +1 IC at 30DAS 24.75 75.37 5297

2.Atrazine 1.25 kg/ha fb Atrazine 0.50 kg/ha 16.53 84.85 5876

3.Atrazine 1.25 kg/ha fb Atrazine 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 fb Atrazine 0.50 kg/ha 17.37 83.40 5817

6.Butachlor 1.00kg/ha fb Atrazine 0.50 kg/ha 14.84 85.18 6020

7.Atrazine 1.25 kg/ha fb 2,4-D 0.5 kg/ha 8.52 91.58 6440

8.Butachlor 1.00kg/ha fb 2,4-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

TreatmentsPlant height

(cm)LAI Net

returns(Rs ha-1)

B: C ratio

T1: Atrazine 1.25 kg/ha +1 IC at 30DAS 180.52 1.82 19602 2.27

T2: Atrazine 1.25 kg/ha fb Atrazine 0.50 kg/ha 185.55 2.21 22991 2.45

T3: Atrazine 1.25 kg/ha fb Atrazine 1.00 kg/ha 190.76 2.37 25130 2.55

T4: Butachlor 1.00kg/ha + 1 IC at 30DAS 179. 16 1.75 17526 2.17

T5: Butachlor 1.00kg/ha fb Atrazine 0.50 kg/ha 182.78 2.07 23005 2.48

T6: Butachlor 1.00kg/ha fb Atrazine 0.50 kg/ha 186.34 2.29 23962 2.52

T7: Atrazine 1.25 kg/ha fb 2,4-D 0.5 kg/ha 193.38 2.54 26601 2.67

T8: Butachlor 1.00kg/ha fb 2,4-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

CD at 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

TreatmentWeed count (per 0.5 m2)

Weed dry weight (per

0.5 m2)

Weed control index (%)

TDMP at harvest of maize (g/plant)

T1 : Atrazine 1.25 kg a.i./ha (PRE) fb. Atrazine 1.50 kg a.i./ha (POST)

4.43 3.87 75.9 292


4.33 4.47 67.4 327

T3 : Atrazine 1.25 kg a.i./ha (PRE) fb. Paraquat 1.0 kg a.i./ha (POST)

3.93 3.10 84.8 304


4.10 3.40 81.5 317

T5 : Atrazine 1.25 kg a.i./ha (PRE) fb. Glyphosate 2.5 kg a.i./ha (POST)

3.08 3.29 82.7 332


3.43 3.36 82.0 284

T7 : 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


3.89 3.91 75.3 292

T9 : 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

T10 : Weedy check 6.23 7.78 0 298SEm+ 0.2 0.0 0.53 3.26CD 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

Treatment100-seed

weight (g)Grain yield

(kg/ha)Net income

(Rs./ha)B:C


36.5 4637 51802 3.48


38.8 4534 50822 3.41


32.8 4791 54725 3.56


37.6 4752 52488 3.38


43.6 5305 59139 3.70


35.7 5283 60702 3.76


34.7 3457 39411 2.90


38.5 4105 41853

T9 : 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

T10 : Weedy check 30.7 2342 20727 2.23SEm+ 0.9 1.91 2509 0.12CD 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

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: Weedy check (no weeding, no intercultivation ) 33.25 0.00 5.13

T2: Mechanical weeding( at 25 DAS and at 45 DAS and IC at 30 DAS )

9.96 27.94 6.94

T3: Atrazine ( 1.00 kg ha—1 pre-em ) + IC at 30 DAS 18.09 16.05 6.31

T4: Atrazine ( 1.25 kg ha—1 pre-em ) + IC at 30 DAS 16.00 18.36 6.49

T5: Atrazine ( 0.75 kg ha—1 pre-em ) fb. 2,4- D ( 1.00 kg ha--1post- em) at 30 DAS

1.78 28.58 7.57

T6: Oxyfluorfen ( 0.25 kg ha—1

post – em) at 20 DAS29.37 24.45 5.45

T7: Weed free check ( IC at 20 DAS and 40 DAS + HW at 30 DAS and 50 DAS)

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

Treatments Grossreturns(Rs.ha-1)

Net returns(Rs.ha-1)

Benefit:cost ratio

T1: Weedy check ( no weeding, no intercultivation ) 69564 42670 2.59

T2: Mechanical weeding( at 25 DAS and at 45 DAS and IC at 30 DAS )

94156 64510 3.18

T3: Atrazine ( 1.00 kg ha--1pre-em ) + IC at 30 DAS

85562 56235 2.92

T4: Atrazine ( 1.25 kg ha--1pre-em ) + IC at 30 DAS

88048 58371 2.97

T5: Atrazine ( 0.75 kg ha--1pre-em ) fb. 2,4- D ( 1.00 kg ha--1post- em) at 30 DAS

102600 72993 3.47

T6: Oxyfluorfen ( 0.25 kg ha--1post – em) at 20 DAS

73899 44726 2.53

T7: Weed free check ( IC at 20 DAS and 40 DAS + HW at 30 DAS and 50 DAS)

104684 73785 3.39

S. Em± 3985.49 3985.49 0.14CD at 5% 11841.49 11841.49 0.42

Table 9 : Economics of maize as influenced by application of herbicides

MARS, Dharwad Shantveerayya, 2010

TreatmentsTotal dry weight of weeds (g m-2)

Weed indexWeed 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. Atrazine 1.50 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 50.1511.Oxyfluorfen 0.15 kg a.i./ha (PRE) 5.64 22.32 57.9612.Maize + cover crop (cowpea) 5.97 31.42 55.5013.Maize + cover cropp (mung bean) 6.55 25.39 51.1914.Weed free check 1.25 - 90.7315.Weedy check 13.42 49.73 -S.Em + 0.44CD at 5% 1.27

Table10 : Total dry weight, weed control efficiency and weed index in maize as influence by weed control treatment

Shailendra singh, 2011ARS, Arabhavi

TreatmentsGrain weight per plant (g)

Grain yield Stover yield

Atrazine 1.00 kg a.i./ha (PRE) 102.97 48.99 70.94Metribuzine 0.25 kg a.i./ha (PRE) 106.00 47.85 72.81Alachlor 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. Atrazine 1.50 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 68.44Oxyfluorfen 0.15 kg a.i./ha (PRE) 97.17 43.16 58.96Maize + cover crop (cowpea) 84.63 38.34 48.75Maize + cover cropp (mung bean) 91.80 41.59 60.63Weed free check 117.67 56.01 76.25Weedy check 83.67 28.11 45.31S.Em + 5.22 3.16 2.67CD 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

Conclusion

Sequential application of herbicides helps to control

weeds on time and for longer period. Pre-emergence application of

atrazine 1.50 kg ha-1/simazine 1-1.5 kg ha -1 helps to control weeds up

to 30 days followed by atrazine 1.50 kg ha-1 (pre-emergence to weed

and post emergence to crop)/2, 4-D @ 1 kg ha-1/ paraquat 1 kg ha-1

(Directed spray)/glyphosate 0.1 kg ha-1 (Directed spray) control after

the new emerging weeds. This will help the farmer in reducing the

burden of labour problem.

FUTURE LINE OF WORK Continuous studies are required on the effectiveness and bio-efficacy

of new generation herbicides and herbicide mixtures in maize crop.

Studies on residual effect of herbicides on crop grown in sequence and also on the environment in long-run needs to be initiated.

The studies are needed on the use of herbicide in granular form.

Use of different new methods of weed control like electromagnetic radiations.

Use of encapsulated herbicides.

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

use of herbicides in sequence for control of weeds in maize

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