Comparison of Yield and Yield Components of Sunflower (Helianthus annuus L.), Sesame (Sesamum indicum L.) and Red Bean (Phaseolus calcaratus) under different Intercropping Arrangements

Introduction \ud Intercropping is a sustainable practice used in many developed and developing countries and an essential element of agricultural sustainability. Intercropping is simultaneous growing of two or more crops during a given season on same location. Such a method enables the utilization of common limiting resources more efficiently 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) and absorption in comparison with the sole cropping (Fernandez-Aparicio et al., 2008). The study of intercropping of borage (Borago officinalis L.) and bean (Phaseolus vulgaris L.) showed 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. The results were compared to respective monoculture and the advantages of intercropping was determined. The effects of planting different ratios of two crops on yield and yield components of sesame (Sesamum indicum L.) and chickpea (Cicer arietinum L.) was also investigated. 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.\ud Materials and Methods \ud To evaluate the effects of different intercropping arrangements of sunflower, sesame and red bean on growth characteristics, yield components and yield, a field experiment was conducted at Agricultural Research Station of Ferdowsi University of Mashhad, Iran during two growing seasons of 2009-2010 and 2010-2011. For this purpose a randomized complete block design with six treatments and four replications was used. Treatments were: (A) one row for each special intercropping, (B) row intercropping (two rows for each species), (C) strip intercropping (four rows for each species) and (D) sole crop of sunflower, (E) sole crop of red bean and (F) sole crop of sesame (twelve rows for each species).\ud Land equivalent ratio (LER)\ud Land equivalent ratio of sunflower, sesame and red bean was calculated (Sullivan, 2003) as:\ud LER= Y1/L1+Y2/I2 \ud Where Y1 and Y2 represent sunflower, sesame and red bean yield in intercropping and L1 and I2 represent sunflower, sesame and red bean yield in mono-culture, respectively.\ud Statistical analyses: SAS ver. 9.1 and MSTAT-C softwares were used for statistical analysis. To compare the means, Duncan's multiple range test at 5% probability level was used.\ud Results and Discussion \ud Results showed that the growth characteristics, yield and yield components of sunflower, sesame and red bean were significantly (p≤0.01) affected by different intercropping arrangements. There was a decreasing trend in these parameters from intercropped towards the sole crop for sesame and red bean and an increasing trend for sunflower. The highest biological and economic yield of sesame (4751 and 2207 kg ha-1, respectively) and red bean (5701 and 2719 kg ha-1, respectively) were observed in monoculture. There was a decreasing trend in land equivalent ratio (LER) from row intercropped toward, strip cropping. Maximum and minimum LER were observed in A and C with 1.38 and 1.02, respectively.\ud Conclusions\ud According to the results, intercropping of sunflower, sesame and red bean can be beneficial in terms of ecological management. In general the arrangements of sunflower, sesame and red bean could be recommended for achieving high yield in sunflower in this region