Evaluation of the Benefits of Oat-Soybean and Oat-Groundnut Intercropping in Jilin Province, China

Abstract

Evaluation of the Benefits of Oat-Soybean and Oat-Groundnut Intercropping in Jilin Province, China
 
Yong, Yang1* and Mohammad hesam Shahrajabian2
1-       Hami melon research center, Xinjiang Academy of Agricultural Sciences
2-       Assistant ProfessorSenior Researcher- Faculty of Agriculture- Islamic Azad University, Isfahan (Khorasgan) Branch, Isfahan, Iran
 
* Corresponding author email: yangyongsj@gmail.com
 
               Received: 7 April 20177                                                                                  Accepted: 24 June 2017
 
Abstract
Mixing species in cropping systems may lead to a range of benefits that are expressed on various space and time scales from a short-term increase in crop yield to long-term increase in sustainable production of foods. In order to determine the benefits of two intercropping systems, oat-soybean and oat-groundnut, an experiment was conducted in research station of Baicheng Academy of Agricultural Sciences in 2011, Jilin province, China. A randomized complete block design with four replications was used. Treatments comprised different mono cropping and intercropping patterns, TO: sole cropping of oat, TOS-O: oat in the intercropping of oat and soybean, TOG-O: oat in the intercropping of oat and groundnut, TS: sole cropping of soybean, TOS-S: soybean in intercropping of oat and soybean, TG: sole cropping of groundnut, TOG-G: groundnut in the intercropping of oat and groundnut. No nitrogen fertilizer was used in this research. The highest seed yield was obtained for mono-cropping of soybean, followed by mono-cropping of groundnut and oat. Oat seed yields in intercropping of oat and groundnut, and intercropping of oat and soybean were 1208.00 kg/ha, and 832.3 kg/ha, respectively. The highest grain yield was obtained when soybean was grown together with oat, where the higher yield of intercrop is due to the better usage of nutrient, water and light. Land equivalent ratio (LER) in all intercropping patterns were higher than 1. LER in intercropping of soybean and oat, and intercropping of groundnut and oat were 1.41, and 1.30, respectively. With these LER values, 29.07% and 23.07% of land were respectively saved in intercropping of soybean and oat, and intercropping of groundnut and oat, respectively, which could be used for other agricultural purposes. In both intercropping of soybean and oat, and intercropping of groundnut and oat, completion index (CI) were less than 1, which means that both these two intercropping patterns have positive effects.
 
Keywords: Oat, Soybean, Groundnut, Intercropping.
 

Keywords


       
 

Original Research

 
   

                 Research on Crop Ecophysiology                                  Vol.12/2, Issue 2 (2017), Pages: 98 -  106

 

 

 
 

 

 

 

Evaluation of the Benefits of Oat-Soybean and Oat-Groundnut Intercropping in Jilin Province, China

 

Yong, Yang1* and Mohammad hesam Shahrajabian2

1-       Hami melon research center, Xinjiang Academy of Agricultural Sciences

2-       Assistant ProfessorSenior Researcher- Faculty of Agriculture- Islamic Azad University, Isfahan (Khorasgan) Branch, Isfahan, Iran

 

* Corresponding author email: yangyongsj@gmail.com

 

               Received: 7 April 20177                                                                                  Accepted: 24 June 2017

 

Abstract

Mixing species in cropping systems may lead to a range of benefits that are expressed on various space and time scales from a short-term increase in crop yield to long-term increase in sustainable production of foods. In order to determine the benefits of two intercropping systems, oat-soybean and oat-groundnut, an experiment was conducted in research station of Baicheng Academy of Agricultural Sciences in 2011, Jilin province, China. A randomized complete block design with four replications was used. Treatments comprised different mono cropping and intercropping patterns, TO: sole cropping of oat, TOS-O: oat in the intercropping of oat and soybean, TOG-O: oat in the intercropping of oat and groundnut, TS: sole cropping of soybean, TOS-S: soybean in intercropping of oat and soybean, TG: sole cropping of groundnut, TOG-G: groundnut in the intercropping of oat and groundnut. No nitrogen fertilizer was used in this research. The highest seed yield was obtained for mono-cropping of soybean, followed by mono-cropping of groundnut and oat. Oat seed yields in intercropping of oat and groundnut, and intercropping of oat and soybean were 1208.00 kg/ha, and 832.3 kg/ha, respectively. The highest grain yield was obtained when soybean was grown together with oat, where the higher yield of intercrop is due to the better usage of nutrient, water and light. Land equivalent ratio (LER) in all intercropping patterns were higher than 1. LER in intercropping of soybean and oat, and intercropping of groundnut and oat were 1.41, and 1.30, respectively. With these LER values, 29.07% and 23.07% of land were respectively saved in intercropping of soybean and oat, and intercropping of groundnut and oat, respectively, which could be used for other agricultural purposes. In both intercropping of soybean and oat, and intercropping of groundnut and oat, completion index (CI) were less than 1, which means that both these two intercropping patterns have positive effects.

 

Keywords: Oat, Soybean, Groundnut, Intercropping.

 

 

 

 

Introduction

 

Mixtures of annual forage legumes with winter cereals for forage production are used extensively in the world (Papastylianou, 2004; Lithourgidis et al., 2006). Intercropping of Cereal-legume has potential benefits in cropping systems, where nutrients are limited (Banik et al. 2006; Hauggaard-Nielsen et al., 2009; Soleymani et al., 2011; Soleymani and Shahrajabian, 2011; Soleymani et al., 2012; Yong et al., 2017). Lauk and Lauk (2008) concluded that, pea-oat mixed intercrops gave the highest grain and protein yield. The land equivalent ration (LER) is the relative land area for growing sole crop that is required to produce the yields achieved when growing intercrops (Dua et al., 2005; Hauggaard-Nielsen et al., 2006; Javanmard et al., 2009). Ebwongu et al. (2001) noticed that in intercropping of potato and corn, LER reached to 1.58, showing the beneficial effect of intercropping. Bekele and Sommartya (2006) found that in potato and garlic intercropping, the amount of LER reached to more than one. LER was more than one in a study of potato and pinto bean intercropping (Nasrollahzadeh Asl et al., 2009). Ghanbari et al. (2010) found that (LERs) were greater in all systems of intercropping with different planting ratio of maize-cowpea. Soleymani et al. (2012) noted that in all intercropping treatments of their experiment, (LER) was more than 1, which indicates yield advantages for intercropping. Ghaderi et al. (2008) showed that the best relative total yield (RYT) for intercropping of alfalfa and wheatgrass was 1.15 and the maximum value of R (yield in intercropping/yield in single cropping) for alfalfa and wheatgrass were 1.02 and 0.36, respectively. Ijoyah and Fanen (2012) reported that 46.5% and 46.2% of land were respectively in 2009, and 2010 for maize-soybean mixture, which could be used for other agricultural purposes. Inspite the fact that there is much published information on the forage quantity and quality of many cereal-legume intercropping systems, there is not enough information on intercropping of oat with soybean and peanut. So, the aim of this study was to determine advantages in mono cropping systems and intercropping patterns of oat-soybean and oat-groundnut.

 

Materials and methods

 

Plant  Materials and growth condition

 

The research was conducted under field conditions in the arid Horqine sandy land in Baicheng District (44o14/-46o18/N, 121o38/-124o22/E), Jilin Province, Northern China in 2011. A randomized complete block design with four replications was used. Treatments comprised different mono cropping and intercropping patterns, TO: sole cropping of oat, TOS-O: oat in the intercropping of oat and soybean, TOG-O: oat in the intercropping of oat and groundnut, TS: sole cropping of soybean, TOS-S: soybean in intercropping of oat and soybean, TG: sole cropping of groundnut, TOG-G: groundnut in the intercropping of oat and groundnut. No nitrogen fertilizer was used in this research. Fifty five kg/ha P2O5, 45 kg/ha K2O, 4.5 kg/ha FeSO4, 1 kg/ha H3BO3, 1.5 kg/ha Na2MOO4.2H2O were applied as basal fertilizers. No fertilizers were used during growth stages. Soybean and groundnut seeds mixed with rhizobia before plantation. The soybean growing pattern in monoculture was 10×60 cm with 1 seedling in each hole, which is equivalent to 167 thousand plants per ha. The groundnut growing pattern in monoculture was 20×60 cm with two seedlings in each hole, equivalent to 167 thousand plants per ha. The seedling rate of oat in monoculture was 200 kg/ha. In soybean and groundnut monoculture, the distance between two rows was 60 cm, and the distance between seedlings on the row was 10 cm and 20 cm, respectively. Oat seed rate per row for both monoculture and intercropping patterns were the same. In intercropping patterns, the distance between both groundnut and soybean row with oat rows were 20 cm. The ratio of both soybean and groundnut intercropping with oat was 2:2. All seeds were sown by skillful workers on May 17. Oat and legumes were harvested on August 12th and September 7th. Intercultural operations such as weeding and plant protection were done when required to ensure and maintain the normal growth of crops.

 

Characteristics Measurement

 

Pod number, the number of seed per pod, seed weight per pod (g), seed weight per plant (g) and a hundred seed weight (g) were determined for soybean and groundnut mono-cropping, intercropping of oat and soybean, and intercropping of oat and groundnut. Plant height (cm), spike length (cm), spikelet number, number of grain per spike, grain weight per plant (g), and a thousand seed weight (g) were measured for oat mono-cropping. The relative total yield (RYT) was also calculated when both crops were sown with the same density. Competition index (CI) was measured as follows; where NA and NB were the number of crop A and B per area, and NA1 and NB1 were the yields of crop A and B in intercropping pattern:

 

 

 

The land equivalent ration (LER) was determined as described by Willey (1985) using  the following formula:

LER= (LERa + LERb) = {(Yab/Yaa) + (Yba/Ybb)}

 

The R values for each crop were determined as ratio of yield in intercropping system to yield in signal cropping.

 

The percentage (%) land saved as described by Willey (1985) was calculated as:

%Land saved= 100- 1/LER × 100

 

Soil Analysis

 

On the basis of soil sample at the depth of 0-20 cm the amount of, organic matter and total nitrogen were 12.4 g/kg, and 0.859 g/kg, respectively. Available nitrogen, phosphorus and potassium were 66.6 mg/kg, 14.2 mg/kg and 68.2 mg/kg, respectively. Soil pH was 7.2.

Statistical Analysis

 

All data were statistically treated using Analysis of variance (ANOVA) for randomized complete block design and the means were compared by Duncan ,s multiple range test using SAS software program (p≤0.05).

 

RESULTS AND DISCUSSION

 

Seed yield was significantly influenced by treatments (Table 1). The highest seed yield (3263 kg/ha) was related to sole cropping of soybean, but it had no significant differences with the yields of soybean in intercropping of oat and soybean (TOS-S) and groundnut in sole cropping (TG). Seed yields in TOS-S and TG were 3018.00 kg/ha, and 3071.00 kg/ha, respectively. Oat in the intercropping of oat and soybean had the lowest seed yield (832.3 kg/ha), followed by oat seed yield in intercropping of oat and groundnut (TOG-O), and oat seed yield in mono cropping (TO). There was not any significant differences between oat yield in oat and soybean, and oat and ground nut intercropping. However, oat seed yield in soybean and oat intercropping had significant differences with other treatments (Table 2). Some other researchers also stated that in intercropping system of cereal with a legume, forage yield is much higher than that of the legume sole crop and cereal seed yield is higher than that of the cereal sole crop (Mariotti et al., 2009; Yolcu et al., 2009).

 

Table 1. Analysis of variance for seed yield in different cropping patterns.

S.O.V

d.f.

Seed yield

Replication

3

50549.429

Treatment

6

3830576.286**

Error

18

170565.206

**significant at 0.01 probability level.

 

Table 2. Mean comparison for seed yield (kg/ha) in different cropping patterns.

Treatment

Seed yield (kg/ha)

TO

1708.00b

TOG-O

1208.00bc

TOS-O

832.3c

TS

3263.00a

TOS-S

3018.00a

TG

3071.00a

TOG-G

1851.00b

Means with acommon letters do not differ significantly. TO: Sole cropping of oat; TOS-O: Oat in the intercropping of oat and soybean; TOG-O: Oat in the intercropping of oat and groundnut; TS: Sole cropping of soybean; TOS-S: Soybean in the intercropping of oat and soybean; TG: Sole cropping of groundnut; TOG-G: Groundnut in the intercropping of oat and groundnut.

 

Treatments had significant influence on pod number, seed weight per pod, seed weight per plant and hundred seed weight. The number of seed per pod was not significantly affected by treatments (Table 3). The highest pod number was related to soybean in mono-cropping, followed by intercropping of soybean and oat and mono-cropping of groundnut. The number of pod in mono cropping of soybean, intercropping of oat and soybean and mono cropping of groundnut were 49.75, 43.75, and 29, respectively. The lowest pod number, (19.50) was obtained for intercropping of oat and groundnut (Table 4).

There was no significant differences in number of seed per pod among treatments. However the maximum value for number of seed per pod was related to mono-cropping of groundnut and intercropping of oat and groundnut. The maximum and the minimum seed weights per pod were achieved for intercropping of oat and groundnut (1.47 g), and soybean mono-cropping (0.60 g). No significant difference was found for seed weight per pod between soybean mono-cropping, and intercropping of oat and soybean. Furthermore, there was no significant difference between groundnut mono-cropping and intercropping of oat and groundnut. Intercropping of oat and soybean had the maximum seed weight per plant, (23.77g). There were no significant differences between soybean mono-cropping, intercropping of oat and soybean, and groundnut mono cropping for seed weight. The minimum seed weight per plant was related to intercropping of oat and groundnut, which was (13.05 g). The highest value for one hundred seed weight was related to intercropping of oat and groundnut (42.50 g) followed by groundnut mono-cropping, intercropping of oat and soybean, and soybean mono-cropping. Intercropping of oat and groundnut had significant differences for one hundred with other treatments. In contrast, the difference in one hundred seed weight between soybean mono-cropping and intercropping of oat and soybean was not significant (Table 4).

 

Table 3. Analysis of variance for pod number, one number of seed per pod, seed weight per pod, seed weight per plant, and a hundred seed weight.

S.O.V

d.f.

Pod number

One number of seed per pod

Seed weight per pod

Seed weight per plant

One hundred seed weight

Replication

3

137.00ns

0.083

0.007ns

0.062

0.167

Treatment

3

759.167**

0.083

0.817**

103.562**

647.500**

Error

9

51.278

0.139

0.007

2.027

0.222

**significant at 0.01 probability level.

 

Table 4. Mean comparison for pod number, the number of seed per pod, seed weight per pod (g), seed weight per plant (g), and one hundred seed weight (g).

Treatment

Pod number

The number of seed per pod

Seed weight per pod (g)

Seed weight per plant (g)

One hundred seed weight (g)

TS

49.75a

3.00a

0.60b

23.38a

19.25c

TOS

43.75ab

3.00a

0.65b

23.77a

20.25c

TG

29.00bc

3.25a

1.32a

22.30a

41.00b

TOG

19.50c

3.25a

1.47a

13.05b

42.50a

Means with cmmon letters within each column do not differ significantly. TS: Soybean in mono cropping. TOS: Intercropping of soybean and oat. TG: Groundnut mono cropping. TOG: Intercropping of oat and groundnut.

 

 

Both plant height and spike length were not significantly affected by treatments. However, treatment effects on spikelet number, number of grain per spike, grain weight per plant and a thousand seed weight was significant (Table 5).  Although, the maximum plant height was obtained for oat in intercropping of oat and groundnut (93.25 cm), it had no significant differences with mono-cropping of oat, and soybean in intercropping of oat and soybean. The maximum and minimum spike length were obtained for  oat in intercropping of oat and groundnut (19.75 cm), and mono cropping of oat (17.50), which had no significant differences with each other (Table 6). The highest value of spikelet number obtained for oat in intercropping of oat and groundnut, followed by oat in intercropping of oat and soybean, and oat mono-cropping, respectively. Of spikelet number between oat in intercropping of oat and groundnut and the other two treatments was significant. Oat in intercropping of oat and groundnut obtained the maximum grain weight per plant (1.40 g), and its differences with other treatments were significant. Oat mono-cropping had significant difference with oat in intercropping of oat and soybean, but its difference with oat in intercropping of oat and groundnut was not significant. The maximum and the minimum one thousand seed weight were achieved for oat in intercropping of oat and groundnut and mono-cropping of oat. Oat in intercropping of oat and groundnut had significant differences with both treatments. In contrast, the difference between oat mono-cropping and oat in intercropping of oat and soybean was not significant (Table 6). In many studies legume-grain intercrops had produced higher seed yield components than pure grain crops (Jensen, 1996; Lauk and Lauk, 2008; Hauggaard-Nielsen et al., 2006; Hauggard-Nielsen et al., 2009)

 

Table 5. Analysis variance for experimental characteristics.

S.O.V

d.f.

Plant height

Spike length

Spikelet number

The number of grain per spike

Grain weight per plant

A thousand seed weight

Replication

3

32.083*

0.111

2.306

44.556ns

0.005

3.102

Treatment

2

52.58ns

5.250ns

64.583**

462.583*

0.366**

91.552**

Error

6

39.500

1.028

2.806

44.472

0.027

6.128

**significant at 0.01 probability level.

 

 

Table 6. Mean comparison for plant height (cm), spike length (cm), spikelet number, the number of grain per spike (g) and one thousand seed weight (g).

Treatment

Plant height

Spike length

Spikelet number

The number of grain per spike

Grain weight per plant

One thousand seed weight

TO

86.00a

17.50a

17.00b

36.50a

0.95ab

18.13b

TOG-O

93.25a

19.75a

24.50a

55.25b

1.40a

26.98a

TOS-S

89.50a

18.25a

18.25b

36.75a

0.82b

19.40b

Means with common letters within each column do not differ significantly. TO: Sole cropping of oat. TOG-O: Oat in the intercropping of oat and groundnut. TOS: oat in the intercropping of oat and soybean.

 

 

R value of oat in intercropping of soybean and oat, and intercropping of groundnut and oat were 0.49 and 0.70, respectively. R value of soybean in intercropping of soybean and oat was 0.92. In intercropping of groundnut and oat, R of groundnut was 0.60. LER intercroppings of soybean and oat, and intercropping of groundnut and oat were higher than 1, (1.41, and 1.30, respectively). LER above 1 means that a large area of farm is needed to produce the same yield of sole crop of each component compare with intercropping (Javanmard et al., 2009; Soleymani et al., 2012). LER and RYT more than one were due to greater ability of crops to capture resources. Ghaderi et al. (2008) also noticed that higher RYT shows the advantages of intercropping than sole cropping. Intercropping soybean with oat gave the highest LER value of 1.41, shwoing that the greatest productivity per unit area was gained by growing the two crops together than by growing them separately. An LER of 1.0 shows that intercropping produces the same yields as of sole cropping, and above 1.0 giving greater yields than sole crops (Arshad and Ranamukhaarachchi, 2012). Higher LER in intercropping farming system showed yield advantage over mono-cropping because better land utilization (Nasrollahzadeh et al., 2009). In agreement with the findings of this trial, many scientists also reported that LER was greater than one in cereal and legume intercrops (Ghosh, 2004; Yildirim and Guvenc, 2005). Land save values, (29.07% and 23.07%) indicated the amount of land advantage obtained in intercropping of soybean and oat, and intercropping of groundnut and oat, respectively. In both intercropping treatments of soybean and oat, and intercropping of groundnut and oat, CI were less than 1, which means that both these two intercropping patterns have positive effects (Table 7).

 

Table 7. R of oat, soybean and groundnut, LER, RYT, land saved (%) and competition index (CI) for intercropping patterns.

Intercropping pattern

R Oat

R Soybean

R Groundnut

LER

RYT

Land saved (%)

Competition Index (CI)

Soybean and Oat

0.49

0.92

-

1.41

1.41

29.07

0.67

Groundnut and Oat

0.70

-

0.60

1.30

1.30

23.07

0.67

LER= Land equivalent ration, RYT= Relative yield total.

 

CONCLUSION

 

The highest seed yield was obtained for mono-cropping of soybean, followed by mono-cropping of groundnut and oat. Oat seed yield in intercropping of oat and groundnut, and oat and soybean were 1208.00 and 832.3 kg/ha, respectively. The maximum grain yield was achieved when soybean was grown with oat. The higher yield of intercropping system is due to the better usage of nutrient, water and light. LER in all intercropping patterns were higher than 1. LER in intercropping of soybean and oat, and intercropping of groundnut and oat were 1.41, and 1.30, respectively. On the bassis of LER values, 29.07% and 23.07% of land were respectively achieved in intercropping of soybean and oat, and intercropping of groundnut and oat, respectively. In both intercropping systems CI were less than 1, which means that both these two intercropping patterns have positive effects. Cereals intercropped with legumes improves the value of agricultural system.

 

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