Study on Effect of Weed Interference and Nitrogen Fertilizer on Performance of Chickpea in Intercropping with Wheat

In order to evaluating wheat-chickpea intercropping in dryland condition with diferent levels of nitrogen fertilizer and weed free and weed iterference conditions an experiment in factorial split plot based on randomized complete block design (RCBD) with three replications carried out during two years (2008-09 and 2009-10) in dryland agricultural research sub-institute Sararood - Kermanshah. The main plots contained factorial plots of N fertilization with 3 levels (N1: no fertilization, N2: 60 kg ha-1 urea for wheat and 20 kg ha-1 for chickpea, and N3: nitragin as a biofertilizer + 30 kg ha-1 urea for wheat, and chickpea no urea); and weed conditions with 2 levels (weed infested and weed free). The third factor as sub-plots arranged in main plots was cropping patterns with 10 levels (P1: wheat sole crop (wh.SC), P2: chickpea sole crop (ch.SC), P3: wh./ch. mixed intercropping (wh./ch.MIC) in 1:1 ratio, P4: wh./ch. MIC in 2:1 ratio, P5: row intercropping (RIC) 1row wh.:1row ch., P6: strip intercropping (SIC) 5wh.1ch.5wh.2ch, P7: SIC 7wh.:2ch., P8: SIC 2wh.:7ch., P9: SIC 9wh.:4ch., and P10: SIC 4wh.:9ch.). Results showed in intercropping system most of studied traits in chickpea were affected by applied factors and interspecific competition. Wheat had higher competition ability to use resources and was dominant on chickpea. Strip intercropping patterns with wider chickpea strip and narrower wheat strip (P8 and P10) had land equivalent ratio (LER) higher than one, and were stable during years. According to results superiority in intercropping drived in low or no application of urea and no weed control, so these results help to organic production of the crops.