Majid Aghaalikahni
Agronomy Department
Tarbiat Modares University

Outline for the main project:
I.
BARLEY / RAPESEED
II. BARLEY / GRASSPEA
III. BARLEY / CHICKPEA
IV. SWEET CORN / MUNGBEAN
Title of current presentation :
Barley/chickpea intercropping as an environmentally- sound tool for weed management in small scale dry land farms

I. Conventional management
Agricultural production systems in many parts of the world have shifted from relatively small-scale polycultures to large-scale continuous monocultures.

I. Conventional management
This shift in agriculture has been driven by advances in breeding and chemical technologies that occurred after World War II.

I. Conventional management
These technologies have allowed growers to manage weeds and crop fertility chemically rather than mechanically (i.e. not reliant on hand pulling and hoeing)

I. Conventional management
Now, with the appropriate fertilizers and pesticides and equipment growers can plant the same crop over a large area, year after year

But we have to know:
Herbicides are the main (sometimes only) method of weed management in these systems. In this way, herbicide applications can be thought of as
“large hammers”.
=
=

Potential problems of the conventional management :
1. Cropping-systems have been greatly simplified (i.e. lower diversity).
2. Continuous cropping presents weeds with a “predictable” environment weeds with biology similar to crop are particularly difficult to control
3. Large hammers evidently don’t work– we still have weed problems!
4. Large hammers select for resistance
5. As more weed species develop resistance, new herbicides must be developed….weeds will eventually develop resistance to these too!
6. Synthetic pesticides and fertilizers can have unintended environmental effects*

*This last point, in particular, has driven much of the current desire/pressure to develop more ecologically-based weed and crop management strategies
Food web

What is the Main strategy in Ecologically-based weed management ?
Why?......
Because greater cropping-system diversity may increase the potential for ecological interactions to regulate pest populations, potentially decreasing the need for intensive chemical
use.

How might one increase cropping-system diversity?
COVER CROPS
CROP ROTATION
INTER-CROPPING
FIELD MARGINS/ HEDGE ROWS
WEEDY STRIPS
LAND-SCAPE LEVEL DIVERSITY

Research hypothesis:
• A major concern for farmers growing grain legumes in low-input systems is their weak competitive ability toward weeds.
• Light, water and nutrient may be more completely absorbed and converted to crop biomass by INTERCROPPING.
• Barley and chickpea have different competitive ability for growth factors.
• They not compete for the same ecological niches.
• Interspecies competition is weaker than intraspecific competition for a given factor.
• Grain legumes / cereal INTERCROPPING may provide an ecological method utilizing competition and natural regulation mechanisms reduce the need for chemical fertilizer and to manage weeds with less use of herbicides.

Alborz Province(representing a semi-arid climate) agricultural research station of Tehran University (Karaj campus)
Altitude: 1321 m
Latitude: 35

49 َ N
Longitude: 51

50 َ E
Precipitation: 243 mm
Soil texture : loam

Mn mg/k g
Zn mg/kg
Fe mg/kg
8.5
1.2
6.5
Mg meq/lit
O. M %
K mg/kg
P mg/kg
3.2
1.17
183 8.9
N
%
Ca meq/lit
Na meq/lit
SAR
%
EC ds/m pH
هنومن قمع
0.62
2.25
1.13
75 0.6
7.8
0-30

factorial of chickpea × Barley mixing ratio as follow
Barley Chickpea
50, 75, and 100 percent of pure stand
50, 75, and 100 percent of pure stand plus two control plots
(pure stand of chickpea and barley, 80 and 160 kg/ha respectively)
Treatments were arranged in a randomized complete blocks design with 3 replications.

(Hordeum vulgare cv.Valfajr)
160 kg/ha

(Cicer arietinum cv.4322)
80 kg/ha

Weed biomass
Weed species frequency
Crops dry matter in pure stand and intercropped treatment

Commom name
Fumitory
Field bind weed
Common lamb. Squarters, Fathen
Prostrate knot weed
Raphistre, Turnip weed
Russian knap weed
Hypecum
Goldbachia
Scientific name
Fumaria asepala
Convonvulus arvensis
Family
Fumariaceae
Convolvulaceae
Chenopoduim album
Polygonum aviculare
Rapistrum rugosum
Acroptilon repens
Hypecum pendulum
Goldbachia laevigata
Chenopodiaceae
Polygonaceae
Brassicaceae
Asteraceae
Papaveraceae
Brassicaceae

(Astearaceae)

(Brassicaceae)

1. Chikpea monoculture has the highest weed density
2.It was was dominantly consisted of fumitory 

3. Barley pure stand was kept weed free 
4. All additive intercropped treatment reduced weed frequency significantly
5. All weed species were suppressed in intercrop treatments except fumitory which was alive up to flowering stage.



1.The highest amount of weed biomass (620 kg/ha) were obtained in chickpea monoculture.

2. Green biomass of chickpea pure stand (220 Kg/ha) suppressed by weed competition.

3. All experimental units including barley, significantly reduced weed biomass.

4. It could be attributed to high growth rate and better establishment of barley comparing to chickpea.

5. It could be concluded that barley has acceptable competition ability against weeds.


400
350
300
250
200
150
650
600
550
500
450 a
100
50 b b
0
C
10
0B
10
0
C
10
0B
75
C
10
0B
50 b b b b b b
C
10
0
C
75
B
10
0
C
75
B
75
C
75
B
50
C
50
B
10
0
C
50
B
75
C
50
B
50 b
B
10
0 b barley(B) and chickpea© mixing ratio

Thank you for your attention
Efharisto ’ poli’
Damavand peak, 5619 masl
(Alborz chain of mountains)
Tehran- Iran

Treatment
C
100
B
100
C
100
B
75
C
100
B
50
C
100
C
75
B
100
C
75
B
75
C
75
B
50
C
50
B
100
C
50
B
75
C
50
B
50
B
100
Mean comparison of forage dry biomass for barley/chickpea intercropping
Chickpea dry matter
(Kg/ha)
64.9
bc
64.26
bc
82.93
b
220.1
a
13.78
d
21.36
cd
79.95
b
12.76
d
7.183
d
33.23
cd
0.0
d
Barley dry matter
(Kg/ha)
2916.16
ab
1693.1
cd
1828.61
cd
0.0
c
2137.33
bc
2077.5
bc
1451.83
d
2554.7
ab
2136.9
bc
1693.9
cd
3056.33
a
Total dry matter
(Kg/ha)
2981.06
ab
1757.4
c
1911.55
c
220.1
d
2151.12
bc
2098.8
bc
1531.8
c
2567.7
ab
2144.1
bc
1726.6
c
3056.33
a