Weed Management for Higher Input-use Efficiency · Weed Control (WC) 1193 865 794 Insect pest/Disease Control (IDC) 913 565 667 ... Paddy (direct seeded) 20-37 5-14 17-48 47-86 Paddy

Weed Management for

Higher Input-use Efficiency

JS Mishra

ICAR-Research Complex for Eastern Region,

Patna 800 014

Farmers’ income can be

raised by

• Increasing productivity

• Reducing cost of cultivation

• Increasing input-use efficiency

Farmers’ income not the production, is the

most appropriate measure of farmers’

wellbeing

Major inputs in crop

production are:

Fertilizer nutrients, Water, Seed, Pesticide,

Labour, land, Energy, Solar radiation, etc

Competition is what weed

control is all about

Light

NutrientsWater

Below ground competition

Above ground competition

What Do Plants Compete For?

Potential losses due to weeds in oilseeds crops in India

Crop No. of

sites

No. of

Expts.

Mean yield (kg/ha) Mean

Loss

(%)Weed

Free

Un-weeded

Soybean 21 50 1926 875 55.2

Groundnut 18 24 2344 874 62.7

Mustard 14 22 1449 955 34.1

Sesame 5 6 664 293 55.9

Sunflower 4 5 1700 1126 33.8

Safflower 1 1 1490 990 33.6

Linseed 4 5 975 359 53.2

Castor - - 720 580 19.4

Niger - - 491 322 34.6

Crop Trials(No.)

Seed yield (kg/ha) Yield loss (%)

WF WI

Pigeonpea 21 1573 747 46.7

Urdbean 18 1001 474 55.4

Mungbean 13 963 516 46.3

Chickpea 13 1545 767 48.1

Field Pea 13 2094 1054 47.1

Lentil 6 1709 755 58.8

Potential Yield loses due to weeds in

different pulse crops

Seed yield of kharif pulses as influenced

by different inputs (Ali and Lal , 1989)

Production inputs

Mean yield (kg ha-1)

Pigeonpea Urdbean Mungbean

Control (C) 911 412 490

Fertilizer (F) 953 645 654

Weed Control (WC) 1193 865 794

Insect pest/Disease

Control (IDC)

913 565 667

Fertilizer + WC 1344 1054 884

Fertilizer + IDC 1244 683 791

WC +IDC 1291 928 860

F+ WC+ IDC 1519 1140 1071

Seed yield of rabi pulses as influenced by different

inputs (Ali and Lal,1989) .

Production inputs

Mean Yield ( kg ha-1)

Chickpea Lentil Pea

Farmers Practice (control) 789 828 950

Full package of practice (FPP) 1794 1424 1810

FPP minus fertilizer 1427 1050 1462

FPP minus inoculation 1631 - -

FPP minus insect pest and

disease control

1490 1048 1508

FPP minus irrigation 1696 1198 1163

FPP minus weed management 1298 1121 1437

Per cent loss due to weeds 27.65 21.28 20.61

Weeds as host ofinsect-pests and pathogen

• Vicia sativa provides shelter to Helicoverpaarmigera

• Ageratum and Lantana provide shelter to white fly

• Solanum nigrum hosts Leuicinodes orbonalis

• Chenopodium album host for aphids

Weed species Organisms Disease/insect-

pests

References

Cynodon dactylon Sporisorium

sorghi

Sorghum covered

smut

Marley, 1995

Sorghum halepense Colletotrichu

m

graminicola

Sorghum

anthracnose

Frederiksen,

1984

Stenodiplosis

sorghicola

Sorghum midge Monaghan,

1978; Bilbro,

2008

Claviceps

africana

Sorghum Ergot Reed et al. 2000

Brachiaria distachya,

Panicum repens, Setaria

intermedia, Cyperus

rotundus

Sorghum Shoot fly Nwilene et al.

1998

Achyranthus sp. Leaf eating

caterpillars of maize

Gupta, 2010

Chenopodium album Stalk borer of maize Gupta, 2010

Saccharum spontaneum Downy mildew of

maize

Gupta, 2010

Weeds as an alternate host for

insect-pests and diseases

Nutrients

• An adequate supply of plant nutrients during the

period of their uptake is essential in order to

achieve optimum crop yields.

• The presence of weeds throughout the cropping

period alters the available nutrient pool in the soil

and dry matter with in the plant.

• A reduced pool of nutrients in the soil results in

development of nutrient deficiency symptoms

earlier in crops when grown in association with

weeds compared to weed free conditions implying

more depletion of soil nutrients under weedy

conditions.

Nutrient depletion and yield losses due to

weeds in important field crops

Crops Nutrient removal due to weeds (kg/ha) Reduction in

grain yield (%)

N P K

Paddy (direct seeded) 20-37 5-14 17-48 47-86

Paddy (transplanted ) 11.0 3.0 10.0 15-38

Maize 23-59 6-10 16-62 40-60

Sorghum 36-46 11-18 31-47 6-40

Wheat 20-90 2.13 28-54 26-38

Pigeonpea 28.0 24.00 14.00 20-40

Greengram 80-132 17-20 80-130 30-50

Cotton 67-75 20-38 30-109 15-25

Chickpea 29-55 3-8 15-72 15-25

Peas 61-72 7-14 21-105 30-30

Lentil 39.0 5.0 21.0 20-30

Soybean 26-65 3-11 43-102 40-60

Groundnut 15-39 5-9 21-24 40-50

Rapeseed & mustard 22.0 3.0 12.0 15-30

Linseed 32.0 3.0 13.0 30-40

Sugarcane 35-162 22-44 135-242 20-30

Nutrient contents in crops and weedsPlant species Nutrients (on dry weight basis) %

N P2O5 K2O

Crops

Rice 1.13 0.34 1.10

Wheat 1.34 0.66 1.50

Maize 1.21 0.20 1.18

Sorghum 0.41 0.24 2.16

Sugarcane 0.33 0.19 0.67

Pearl millet 0.64 0.74 2.50

Pulses 1.24 0.54 1.31

Weeds

Echinochloa colona 2.95 0.62 2.50

Amaranthus viridis 1.90 1.52 3.12

Xanthium strumarium 2.50 0.70 2.50

Chenopodium album 3.50 1.40 3.45

Commelina benghalensis 2.12 1.50 1.90

Phalaris minor 1.78 0.84 1.90

Cynodon dactylon 2.05 1.45 1.25

Cyperus rotundus 1.65 1.50 1.24

Mineral Composition of Corn and Weeds

Species Mean percent composition

N P K Ca Mg

Common lambsquarter 2.6 0.4 4.3 1.5 0.5

Common purslane 2.4 0.3 7.3 1.5 0.6

Corn 1.2 0.2 1.2 0.2 0.2

Crabgrass 2.0 0.4 3.5 0.3 0.5

Galinsoga 2.7 0.3 4.8 2.4 0.5

Pigweeds 2.6 0.4 3.9 1.6 0.4

Ragweeds 2.4 0.3 3.1 1.4 0.3

Smartweeds 1.8 0.3 2.8 0.9 0.6

(Vengris et al., 1953)

Global nitrogen fertilizer efficiency of cereal

production (annual global cereal production/annual global nitrogen fertilizer

production for domestic use in agriculture)

Tilman et al. 2002

Nitrogen-use efficiency in different

countries

Country Year NUE

(kg/kg)

Change

(%)

Rate of

change

(% per year)

USA 1980 42 - -

2000 57 +36 1.6

UK 1981-1985 36 - -

2001-2002 44 +23 1.1

Japan 1985 57 - -

2001 75 +32 1.8

India 1970 60 - -

2004 20 -60 -1.7

Patil, 2009

Fertilizer N efficiency of maize from 56 on-

farm studies in north central USA

Parameters Values

Average optimum N fertilizer rate, kg/ha 103

Fertilizer N recovered in the crop, kg/ha 38

Total N taken up by crop, kg/ha 184

N removed in the harvested grain, kg/ha 103

N returned to field in crop residue, kg/ha 81

Crop recovery efficiency (38 kg N

recovered/103 kg N applied), %

37

Crop removal efficiency (103 kg N

applied/103 kg N in grain), %

100

Cassman et al. (2002), source of data, Bruulsema et al. (2004), source of calculations

Nitrogen fertilizer recovery efficiency by

maize, rice, and wheat from on-farm

measurements

Crop Region No. of

farms

Av. N rates

Kg/ha

N recovery

(%)

Maize North Central USA 56 103 37

Rice Asia – farmer

practice

179 117 31

Asia – field-specific

management

179 112 40

Wheat India – unfavorable

weather

23 145 18

India – favorable

weather

21 123 49

Cassman et al. (2002)

Weed competition for

nitrogen in rice

Weeds Tons/ha of rice grain with

nitrogen fertilizer applied

at (kg/ha)

0 60 120

None 4.5 5.3 6.6

Barnyardgrass 4.4 4.0 5.5

Barnyardgrass

+ Monochoria

4.1 3.1 3.5

Moody, 1981

Nitrogen uptake (kg/ha) of

weeds and rice in two trials

Species Trial I Trial II

Weeds

present

Weeds

absent

Weeds

present

Weeds

few

Rice 36.8 99.7 15.5 111.8

Barnyard

grass

56.3 0 94.1 1.6

Total 93.1 99.7 109.6 113.6

Boerema, 1963; De Datta, 1981

Nutrient removal (kg/ha) by

weeds and pulses crops

Crops Nitrogen Phosphorus Postasium

Crop Weed Crop Weed Crop Weed

Greengram

(rainy season)

12.4 132.2 5.3 17.6 10.3 130.1

Greengram

(spring

season)

55.6 79.1 10.2 19.8 49.1 79.1

Blackgram 73.4 76.3 - - - -

Chickpea 32.3 54.6 5.4 7.7 47.3 72.4

Peas 30.6 71.6 5.8 14.4 33.1 150.0

Singh, 1993

Competition for water

• Competition for water in a crop-weed situation increases

water stress for the crop due to presence of weeds.

• The effect of water stress on crop is a function of the

developmental stage at whichthe stress occurs, duration

and severity of stress and weed species present.

• Under weedy situations, plants develop water stress

symptoms (i.e. lower leaf water potential, reduced leaf

stomatal conductance, reduced leaf photosynthesis) earlier

than when grown in the absence of weeds, suggesting

limited water availability under weedy conditions.

• This might be due to less developed root system under

weedy condition, rather than water availability per se

(Rajcan and Swanton, 2001).

Moisture stress due to weeds

in sorghum

Weedy check Atrazine as pre-em.

Field CropsTranspirat

ion ratioWeeds

Transpirati

on ratio

Sorghum 304 Pigweeds 287

Corn 349 Lambsquarter 801

Sugar beets 377 Gumweed 608

Soybean 646 Ragweed 948

Wheat 528

Dry beans 700

Transpiration ratio (T: R1) of various crops

and weed species

Croissant et al. (2014)

Weed Management practices

for increasing NUE

Weed competitive crop cultivars

Excellent suppression of weeds by pea cultivar ‘JP 885’

Weed suppression by rice variety ‘Vandana’ in direct seeded conditions

Evaluation of upland

rice cultivars for

weed competitive

ability

– Growing of weed competitive cultivars is an important prerequisite forminimizing weed problems.

– Vandana and RR151-3 were found to be tolerant to weed competitionand performed better than other varieties

0

0.5

1

1.5

2

2.5

Gra

in y

ield

(t/h

a)

Weedy One HW Weed free

Weed management

Heera Vandana

Stale seed bed technique

Effect of seeding methods on weed growth,

nutrient uptake and grain yield of rice

Seeding

method

Weed

dry wt.

(kg/ha)

Nutrient uptake

by weeds (kg/ha)

Grain

yield

(kg/ha)

Nutrient removal

by rice (kg/ha)

N P K N P K

Broadca

sting

179.8 44.6 6.3 68.2 1660 22.2 6.6 36.7

Drilling 153.2 37.1 5.5 56.8 1920 26.5 7.8 42.1

Line

sowing

162.1 38.4 5.4 57.6 1830 25.6 7.1 40.6

Chandrakar and Chandrakar, 1992

Effect of planting method on weed dry

weight, nutrient uptake and grain yield in

rice

Treatme

nt

Weed

dry wt.

(kg/ha)

Nutrient uptake

by weeds (kg/ha)

Grain

yield

(kg/ha)

Nutrient removal

by rice (kg/ha)

N P K N P K

Direct

sown

(Dry)

198.1 26.1 8.1 25.8 1474 44.9 13.6 49.3

Direct

sown

(Puddled)

148.4 20.5 5.4 16.5 2827 83.1 21.6 87.2

Transpla

nted

92.7 10.9 2.6 9.3 3907 100.2 28.2 103.8

CD at 5% 8.8 1.5 0.15 1.3 397 2.8 0.8 4.1

Singh and Sharma, 1981

Effect of methods urea application

on rice yield

Method % reduction in

yield due to

weeds

Mudball 19.2

Supergranule 22.4

Split application 26.2

Basal application 35.4

Moody, 1981

Treatment

Nutrient depletion

by weeds (kg/ha)

Nutrient uptake by crop (kg/ha)

N P K

N P K Grain Straw Grain Straw Grain Stra

w

Level of N (kg/ha)

40 11.0 3.4 14.7 28.7 15.4 6.0 5.3 6.2 41.1

80 13.8 3.6 17.3 34.2 17.9 7.4 5.5 7.8 47.6

120 15.8 3.7 19.4 38.6 19.8 7.7 5.6 8.1 51.8

CD( P=0.05) 0.5 0.3 1.0 1.7 0.6 0.4 NS 0.4 1.9

Time of application

½ at 20 DAS + ¼ at

tillering + ¼ at PI

12.4 3.3 15.8 37.7 19.6 8.0 5.9 8.5 51.9

½ at sowing + ¼ at

tillering + ¼ at PI

14.2 3.7 18.3 26.7 15.1 6.1 5.1 6.2 41.0

CD( P=0.05) 0.6 0.3 0.8 1.4 0.8 0.5 0.5 0.3 1.7

Weed management

Weedy check 28.7 7.3 35.3 7.5 6.3 1.7 2.2 1.8 17.7

Butachlor at 1.5

kg/ha + 1 HW

6.7 1.8 8.8 44.5 22.9 9.5 6.9 9.9 59.5

CD( P=0.05) 0.6 0.3 0.8 1.4 0.8 0.5 0.5 0.3 1.7

Effect of nitrogen and weed management on nutrient

uptake by weeds and rice

Sharma et al. (2007)

Weed management

Grain yield

(t/ha)

Uptake by crop

(kg/ha)

N depletion by

weeds (kg/ha)

40 80 120 40 80 120 40 80 120

Weedy check 0.90 0.64 0.38 16.9 13.6 10.9 21.7 29.0 32.3

Two hand weeding

at 20 and 40 DAS

2.85 3.83 4.18 53.5 71.4 82.3 4.4 6.3 8.0

Butachlor at 1.5

kg/ha + 1 HW

2.79 3.82 4.16 51.6 69.7 81.1 4.9 7.0 8.3

Butachlor at 1.5 +

2,4-D at 1.0 kg/ha

2.34 2.95 3.03 42.8 53.7 59.1 10.0 12.9 14.7

Grain yield nitrogen uptake in rice

Sharma et al. (2007)

Mean magnitude of reduction in nutrient

uptake of weed species in wheat

Weed

Species

Percent reduction in nutrient uptake due to

Closer row spacing

over wider row

spacing

High seed rate over

normal seed rate

Cross sowing over

one direction

sowing

N P K N P K N P K

P. minor 17 11 25 14 16 30 15 10 16

A.

ludoviciana

4 14 27 13 15 30 7 12 14

L. aphaca 23 18 30 12 14 15 15 11 20

V. sativa 32 23 27 10 12 19 18 15 21

Other weed

species

6 17 12 9 11 15 7 9 10

Total weeds 16 15 25 13 14 28 13 11 16

Percent Increase in nutrient uptake by wheat

Crops 17 22 19 17 16 19 25 18 16

Effect of herbicides, rates and time of nitrogen

application on total nutrient uptake by wheat

Treatments Total nutrient uptake

by crop (Kg/ha)

Grain

yield

(t/ha)

N uptake

efficiency

(%)N P K

Herbicides

SSF+MSM (32g) 119a 23a 114a 4.81a 85.8a

Carfentrazon (10g)+

Fenoxaprop (100g)

103b 20b 101ab 4.51b 77.4b

Weedy check 80c 15c 75c 3.57c 57.9c

N rate (kg/ha)

120 96b 18b 91b 4.01b 79.8a

160 108a 20a 102a 4.52a 67.6b

Time of N application

50% Basal +50% CRI 105b 19b 100b 4.31b 75.8b

50% Basal +25%

CRI+25% at flowering

117a 21a 117a 4.46a 84.9a

33.3% Basal +33.3%

CRI+33.3%flowering

84c 16c 72c 4.02c 60.6c

Singh et al. 2015

Grain yield of wheat (kg/ha) as

influenced by weed management and

N-levels

Weed

Management

practices (W)

Nitrogen levels (kg/ha)

0 40 80 120 160 Mean

Weedy Check 560 1385 2321 2695 1710 1734

Methabenzthi

azuron (1.4

kg/ha)

978 1830 2830 2715 2545 2179

Metoxuron

(1.0 kg/ha)

1080 2063 2755 2525 2421 2169

Manual

weeding (one)

855 1580 2685 2434 2283 1967

Mean 868 1714 2647 2592 2239

CD (P=0.05 W N WxN NxWRathi and Tewari, 1981

Regression equation, N-optima and

response per kg of nitrogen in

different weed management practices

Weed Management Regression

equation

N optima

(kg N/ha)

Response

(kg grain)

per kg of N

Weedy Check Y=8.79+9.44x-

1.25x2

126.8 20.98

Methabenzthiazuron

(1.4 kg/ha)

Y=11.20+12.26x-

2.01x2

106.8 27.99

Metoxuron

(1 kg/ha)

Y=13.02+10.86x-

1.92x2

96.4 29.43

Manual weeding

(one)

Y=12.25+10.99x-

1.78x2

106.4 27.45

Rathi and Tewari, 1981

Treatment

Nutrient depletion by

weeds (kg/ha)

Nutrient uptake by

wheat (kg/ha)

N P K N P K

Moisture level

100% ASM 4.1 0.7 6.4 98.9 28.4 47.1

95% ASM 4.4 0.7 6.9 94.1 27.0 44.3

90% ASM 4.7 0.8 7.7 92.6 25.0 38.8

85% ASM 5.2 0.8 8.7 86.1 23.6 34.4

80% ASM 6.0 0.9 9.4 80.8 22.0 30.1

CD( P=0.05) 0.6 0.1 1.3 9.0 3.6 10.2

Weed control

Weedy check 7.2 1.1 11.3 80.1 21.9 33.0

Isoproturon (0.75 kg/ha) 4.8 0.8 7.8 93.1 25.9 39.9

Clodinafop (0.06 kg/ha) 4.9 0.8 8.0 91.0 25.5 39.2

Clodinafop (0.06 kg/ha)fb 2,4-

D (0.50 kg/ha)

2.6 0.4 4.3 97.8 27.5 43.7

CD( P=0.05) 0.4 0.1 0.8 2.9 1.4 3.4

Effect of moisture levels at time of herbicides

application and weed control on nutrient depletion

by weeds and uptake by wheat

Jain et al. 2014

Weed Control

Moisture level

100%

ASM

95%

ASM

90%

ASM

85%

ASM

80%

ASM

Mean

Weedy check 5.1 5.1 5.0 4.9 4.8 5.0

Isoproturon

(0.75 kg/ha)

6.3 6.1 5.8 5.5 5.3 5.8

Clodinafop

(0.06 kg/ha)

6.2 6.1 5.7 5.5 5.2 5.7

Clodinafop

(0.06 kg/ha)

fb 2,4-D (0.50

kg/ha)

6.7 6.5 6.1 5.8 5.5 6.1

Mean 6.1 5.9 5.6 5.4 5.2 5.7

Effect of moisture levels at time of herbicides

application and weed control on grain yield

(t/ha) of wheat

Jain et al. 2014

Effect of weed management practices on nutrient

uptake by crop and weeds in greengram

Komal et al. 2015

Treatment

Nutrient uptake (kg/ha) GY

(t/ha)

Net

Returns

(×103

/ha)

Crop Weeds

N P K N P K

Pendimethalin

0.75 kg/ha

79.5 10.5 79.7 8.68 1.68 7.01 1.08 40.70

Pendimethalin

0.75 kg/ha +

HW 30 DAS

94.2 12.1 91.6 0.73 0.14 0.59 1.22 40.99

Weedy check 45.0 6.02 46.3 61.9 12.1 51.3 0.62 15.19

Weed free 97.2 12.6 94.6 0.00 0.00 0.00 1.25 50.10

LSD (P=0.05) 19.1 2.36 16.7 0.62 0.12 0.64 0.24 10.40

Treatment

Nutrient uptake (kg/ha)

Weeds Sugarcane

N P K N P K

Fertility level (% recommended dose)

75 10.7 4.4 16.4 131.2 35.2 239.2

100 10.3 4.2 16.2 181.7 44.8 272.7

125 9.6 4.2 15.9 188.1 46.4 276.0

CD( P=0.05) NS NS NS 3.4 1.4 8.5

Weed management

Weedy check 32.4 13.6 51.9 116.9 30.4 210.9

Weed free 0.0 0.0 0.0 201.1 53.4 301.0

3 hoeing at 30, 60 and

90 DAP4.3 1.8 6.7 182.3 45.4 277.8

1 hoeing at 30 DAP fb.

Atrazine @ 2.0 kg/ha8.9 3.7 14.1 163.6 41.6 261.8

Atrazine @ 2.0 kg/ha +

2,4-D @ 1.0 kg/ha at 60

DAP

11.0 4.5 17.5 147.1 35.6 241.9

CD( P=0.05) 0.6 0.3 1.1 8.4 2.1 11.9

Effect of fertility levels and weed management on nutrient

uptake in spring-planted sugarcane

Kumar et al. 2014

Effect of laser land leveling and planting techniques on water productivity of wheat (Jat et. al. 2011)

Treatments Average oftotal numberof irrigationsapplied year-1

IrrigationWater use(m3·ha–1)

Irrigation waterproductivity(kg·grain·m–3water)

Precision leveling with raised bed planting

4.5 2.403 2.15

Traditional levelingwith raised beds

4.5 3.103 1.57

Precision leveling with flat beds

4.5 3.293 1.44

Traditional levelingwith flat beds

4.5 4.790 0.93

Raised-bed planting

• Raised bed planting and ridges systems have been used for weed control, increased WUE and plant productivity.

• Raised bed planting helped in saving of 27% irrigation water and raising crop yield by 16.6% compared to flat planting under precision land leveling (Shear , 1985)

• In maize crop, after 4 years of experimental in farmers’ fields, there were raises of 30%, 32% and 65% in grain yield, water saving and water productivity, respectively, under permanent raised beds compared to basins (Jat et. al. 2011).

• Similarly, permanent raised beds showed 13%, 36% and 50% higher grain yield, water saving and water productivity, respectively, for the wheat crop.

• Weed infestation was also 24% in maize and 31% wheat under permanent raised beds, which maintained lower soil bulk density and high infiltration rates

• Raised bed and ridge sowing methods of wheat plantation saved 22.47 and 13.26% irrigation water, and significant higher wheat yield by 24.5 and 20.9%, respectively over flat sowing either by drilling or broadcasting (Ali et al. 2012)

CT wheat

ZT wheat

Zero tillage

Effect of drip and furrow irrigation on

weed intensity in cabbage

Days after

transplanting

Number of weeds/m2 Dry weight of weeds

(g/m2)

Drip Furrow Drip Furrow

30 1409 1844 128 157

60 948 1530 129 170

80 352 1165 44 61

Mulching

Mulch(t ha-1)

Soil moisture content (%) Weed biomass(t ha-1)

Grain yield(t ha-1)

3WAS 5WAS 7WAS 9WAS

0 12.5 7.6 10.1 11.9 2.09 2.16

2 14.8 9.5 13.0 12.9 1.01 3.48

4 16.4 10.9 14.1 14.0 0.89 4.05

6 19.3 13.1 17.8 15.2 0.31 5.52

8 21.9 14.8 19.6 16.8 0.18 5.69

LSD (P=(0.05)

2.1 1.7 2.2 1.5 0.74 1.25

Uwah and Iwo (2011)

Mulching in potato with water hyacinth

Tractor mounted sprayer

…however, poor application techniques result in poor control. (CCS HAU, Hisar)

Uncontrolled phalarisresulting from poor herbicide

distribution

Sulfosulfuron 25 g Clodinafop 60 g

Conclusions

• Weeds compete with crop plants for water,

nutrients, and sunlight, thereby reducing crop

yields and consequently input-use efficiency.

• Nutrient/moisture drain by unchecked weed

growth assumes added significance in the current

context of fertilizer/water crisis involving non

availability and higher costs.

• While adopting the modern crop production

technologies with higher inputs for maximum

yield and profit, efficient weed management

becomes even more important, otherwise the

weeds rather than the crops get benefits from the

costly inputs.

• IWM as a part of Integrated Crop Management is

the KEY.