Effect of Effective Microorganisms (EM) on the Growth and Yield of Crops
O Chol-Min, Kim Won-Hui, Ho Chol- Su, Ri Ok-Son and Yang Sun-Hui
Research Center for Compound Microorganisms, Pyongyang, DPR Korea
Abstract. EM improves the growth and the yield of crops increasing the beneficial microorganisms populations in soil and nutrient uptake by plant. In this paper, effect of EM on growth and yield of crops was tested through microplot and field experiments.
The experimental results showed that early treatment of EM-1 at the growth stage of rice seedlings was suitable.
The use of EM improved also the root growth and total nitrogen and chlorophyll contents, and then increased the yield of paddy rice and Chinese cabbage.
Key words: EM, growth and yield of crops, paddy rice, cucumber and Chinese cabbage
----------------------------------------------------------
Plant and microorganisms have been continuously developed in interaction of the proper symbiosis and co-exist by themselves.Therefore, maintaining of ecological stability of microbes in soil and increasing of maximum action are important ways for conservation of soil and safety of crop production.
In present, EM technology becomes an important one for providing sustainable and safe agricultural production. EM is a mixed culture of various bacteria, Actinomyces, yeast and fungi, it has been proved to be very useful and effective in agriculture.
It is important to display the property of EM as a living entity and to clarify the mechanism of physiological action,to apply it reasonably.
We carried out studies to elucidate the effect of EM on the growth and yield of crops.
Material and Methods
- EM-1, EM-3, and EM-4 as microbial inoculants
- Paddy rice (Pyongdo-3), cucumber and Chinese cabbage as plant materials
The micropot and field experiments were conducted according to the orthogonal array table Lg (41x24), as shown in Table 1.
Table 1. Factors and Levels for micropot experiment
|
Factors
|
Levels
|
1
|
2
|
3
|
4
|
|
|
A:
|
Kind of EM
|
water
|
EM-1
|
EM-3
|
EM-4
|
|
B:
|
Dilutions of EM
|
1:1000
|
1:10000
|
|
|
|
C:
|
Frequency of EM application (times)
|
1
|
2
|
|
|
|
D:
|
EM treatment time
(days before sowing)
|
1
|
15
|
|
|
|
Results and Discussion
Fig 1. Effect of EM on the germination of seeds
 |
|
 |
|
|
 |
|
 control
|
|
|
 EM-1
|
|
 EM-3
|
|
 EM-4
|
|
Germination rate (%)
|
paddy rice
|
cucumber
|
|
|
Table 2. Effect of kinds of EM on the growth of seedlings
|
crop
|
treatment
|
root length
(cm)
|
leaf area
(cm2)
|
height
(cm)
|
dry matter
(g/100 plants)
|
|
shoot
|
root
|
|
rice
|
control
|
1.22
|
-
|
10.53
|
1.04
|
0.54
|
|
EM-1
|
11.75
|
-
|
11.45
|
1.08
|
0.82
|
|
EM-3
|
11.78
|
-
|
10.65
|
1.00
|
0.79
|
|
EM-4
|
11.43
|
-
|
11.40
|
1.10
|
0.62
|
|
cucumber
|
control
|
-
|
6.78
|
11.60
|
0.74
|
0.20
|
|
EM-3
|
-
|
9.83
|
12.30
|
0.78
|
0.24
|
|
Table 3. Effect of EM application time onthe growth of rice seedlings
|
application time
|
height
(cm)
|
root length
(cm)
|
number of roots
|
dry matter
(g/100 plants)
|
|
shoot
|
root
|
|
1st day before sowing
|
15.67
|
11.58
|
4.8
|
0.740
|
0.390
|
|
15th day before sowing
|
16.46
|
12.67
|
5.8
|
0.748
|
0.400
|
|
Table 4. Effect of EM on mobilization of nitrogen in soil
|
treatment
|
mobile -N
(mg/100g soil)
|
increase content
|
increase rate (%)
|
|
control
|
2.67
|
-
|
100
|
|
EM-1
|
3.04
|
0.37
|
113.8
|
|
EM-3
|
2.83
|
0.16
|
105.9
|
|
EM-4
|
2.84
|
0.17
|
106.4
|
|
Table 5. Effect of EM on chlorophyll contents of cucumber and Chinese cabbage
|
treatment
|
cucumber
|
Chinese cabbage
|
|
chlorophyll
|
increase rate (%)
|
1
|
2
|
|
control
|
0.144
|
100
|
0.361
|
100
|
|
EM-1
|
0.160
|
111.1
|
0.435
|
120.5
|
|
EM-3
|
0.164
|
113.8
|
0.536
|
148.6
|
|
Table 6. Effect of EM-1 application amount on the yield of paddy rice
|
treatment
|
yield
(tons/ha)
|
increase yield
(tons/ha)
|
increase rate (%)
|
|
|
control
|
5.10
|
-
|
100
|
|
EM 120kg/ha
|
5.41
|
0.31
|
106.1
|
|
EM-300kg/ha
|
5.58
|
0.48
|
109.4
|
|
EM 500kg/ha
|
5.50
|
0.40
|
107.8
|
|
Table 7. Effect of EM on the yield of Chinese cabbage.
|
treatment
|
yield
(tons/ha)
|
increase yield
(tons/ha)
|
increase rate (%)
|
|
|
control
|
61.51
|
-
|
100
|
|
EM-1
|
66.46
|
4.95
|
108.0
|
|
EM-3
|
67.92
|
6.41
|
110.4
|
|
|
