پديد آورندگان :
رضايي چيانه، اسماعيل نويسنده دانشكده كشاورزي، دانشگاه اروميه , , قلي نژاد، اسماعيل نويسنده ,
كليدواژه :
افت واقعي عملكرد , پروتيين دانه , نسبت برابري زمين , اسانس , سودمندي كشت مخلوط
چكيده لاتين :
Introduction
Intercropping as a cropping method for sustainable agriculture is simultaneous growing of two or more crops during a given season on same location. Such a method enable to utilize common limiting resources more efficient than the species grown separately. Using two species with different growth habits and the least competitive characteristics in intercropping, increases the efficiency of resources (light, water and nutrients) absorbtion in comparison with the sole cropping. Pooramir et al. (2010) investigated the effects of planting different ratios of two crops on yield and yield components of sesame (Sesamum indicum L.) and chickpea (Cicer arietinum L.). The results of intercropping of additive series showed that the highest grain and biological yield of chickpea were obtained through monoculture and the lowest grain and biological yield of chickpea achieved by planting ratio of 100% sesame and 10% chickpea. Koocheki et al. (2012) studied the intercropping of borage (Borago officinalis L.) and bean (Phaseolus vulgaris L.) and reported that the highest economic yield was achieved in monoculture and the lowest economic yield was obtained in four rows of borage plus four rows of bean, but the maximum land equivalent ratio was calculated in 2:2 intercropping. The aim of current study was to determine the best combination and efficiency of resource utilization in intercropping of additive series of chickpea and black cumin. It is compared to respective monoculture and the advantage of intercropping.
Materials and methods
A field experiment was conducted based on randomized complete block design with three replications in West Azerbaijan province- city Nagadeh, Iran in 2012-2013. Treatments included 100% black cumin +10% chickpea, 100% black cumin + 20% chickpea, 100% black cumin + 30% chickpea, 100% black cumin + 40% chickpea and 100% black cumin + 50% chickpea and monoculture of chickpea and black cumin. The experimental plot size was 4 m × 3.2 m involving 8 rows with inter–row spacing of 0.4 m. There were 7 and 5 cm distance between chickpea and black cumin seeds sown on rows, respectively. Cow manure (20 t.ha-1) without any chemical fertilizer, were distributed and plowed into the upper 20 cm of the soil before sowing time. Weeds were controlled by hand, several times during growing season. Black cumin was harvested when they turned brown, dried and shelled, and chickpea was harvested when the first pod of the plants was fully matured and dried. The essential oil of black cumin seeds (v/w) was isolated from 30 g of air-dried and powdered seeds with 300 ml distilled water by conventional hydro-distillation for 3 h using a Clevenger-type apparatus (Clevenger, 1928). Grain protein content was also measured using Kejeldahl.
Land equivalent ratio (LER)
Land equivalent ratio of black cumin and chickpea was calculated using equation 1 (Vandermeer, 1990):
Where Y1 and Y2 represent chickpea and black cumin yield in intercropping and L1 and I2 represent chickpea and black cumin yield in mono-culture, respectively.
Actual yield loss (AYL)
The Actual yield loss (AYL) index provides more accurate information about the competition than the other indices. The AYL is calculated according to the following formula (Equations 2, 3 and 4):
AYL = AYLa+ AYLb
Intercropping advantage (IA)
Intercropping advantage (IA) was estimated as IA = AYL × Price of cumin or chickpea. Intercropping advantage (IA) of the intercropped components was calculated as (Vandermeer, 1989) (Equation 5):
Where Pa is the price of cumin and Pb is the price of chickpea (Vandermeer, 1989).
Statistical analyses
SPSS 16 software was used for statistical analysis. To compare the means, Duncanʹs multiple range test at 5% probability level was used.
Results and discussion
Different planting ratios had significant effects on study traits of chickpea and black cumin (except essential oil yield of black cumin). The highest seed and biological yield of chickpea were achieved through monoculture with 1105 and 14479 kg ha-1, respectively. The results showed that the maximum seed and biological yield of black cumin were obtained at monoculture with 750 and 2310 kg.ha-1, respectively. The highest percentage of grain protein (23%) and essential oil percentage (1.47%) were related to the treatment of 100% black cumin +50% chickpea, respectively. Results showed that LER values were greater than one in all the intercropping combinations of black cumin and chickpea. Land equivalent ratio (LER=1.74) was recorded considering the treatment of 100% black cumin+10% chickpea, indicating additional 0.79 unit of land would have been needed to get equal yield to planting black cumin and chickpea in monoculture. The highest actual yield loss (AYL=6.45) and intercropping advantage (IA=1.70) obtained employing 100% black cumin+10% chickpea, respectively. It seems that 100% black cumin+10% chickpea is remarkably effective in increasing the economic income and land use efficiency.
Conclusion
The results showed that yield and yield components of both species were affected by planting ratio. By increasing the planting ratio, yield and LER of both species decreased due to complementary and facilitative effects in intercropping. Increasing the planting ratio of chickpea, increased the essential oil percentage of black cumin that was probably due to nitrogen concentration. Results of advantages indices showed that intercropping treatment of 100% black cumin+10% chickpea was suitable for increasing the income of farmers and land use efficiency.
Keywords: Actual Yield Loss, Essential oil, Intercropping advantage, Land equivalent ratio, Seed protein
References
Koocheki, A., Shabahang, J., Khorramde, S., and Amin-Ghafouri, A. 2012. Row intercropping of borage (Borago officinalis L.) with bean (Phaseolus vulgaris L.) on possible evaluating of the best strip width and assessing of its ecological characteristics. Journal of Agroecology 4(1): 1-11. (In Persian with English Summary)
Pooramir, F., Nassiri Mahallati, M., Koocheki, A., and Ghorbani, R. 2010. Effect of different planting combinations on yield and yield components of sesame and peas intercropping in additive series. Iranian Journal of Field Crops Research 8(3):393-402. (In Persian with English Summary)
