evaluation of yield and radiation use efficiency of winter wheat (triticum aestivum l.) and sugar beet (beta vulgaris l.) in relay intercropping

introduction intercropping plays an important role in agriculture because of beneficial interactions. intercropping of legumes and cereals is an old practice in tropical agriculture dating back to ancient civilization. cereals and other plant intercrops could substantially increase forage quantity and quality and decrease the requirement for protein supplements. intercropping of cereals and other plants is important for development of sustainable food production systems. this may be due to some of the potential benefits of intercropping systems such as high productivity and profitability, improvement of soil fertility, efficient use of resources, reducing damage caused by pests, diseases and weeds and improvement of forage quality the main advantage of intercropping is more efficient utilization of the available resources and the increased productivity compared to sole crops of the mixture. therefore, this experiment was conducted to evaluate agronomic characteristics of wheat and land equivalent ratio (ler) under relay intercropping with sugar beet. materials and methods in order to evaluate radiation use efficiency (rue), yield and dry matter accumulation in winter wheat relay intercropping and sugar beet, a field experiment was conducted at agricultural research station of ferdowsi university of mashhad, iran, during 2012 growing season, using a completely randomized block with four replications. the experimental treatments included four treatments intercropping ratios of rows: 3: 1, 3: 2, 4: 2, 6: 2 (beet and wheat) with monocropping beet and monocropping wheat (sole crops), comprised the experimental factors. results and discussion the results of this experiment showed that the effects of intercropping were significant for many study traits. also, the results showed that during the growing season, leaf area index, radiation crossing the canopy, radiation use efficiency, the amount of dry matter production and yield per unit area were affected by intercropping. the highest yield of wheat was observed in the intercropping treatments 4: 2 (1942 g.m-2) and the highest dry matter of beet sugar was obtained in monoculture (2063 g.m-²). highest radiation use efficiency of wheat and sugar beet) was observed in treatment 4: 2 (65.1 and 38.2), respectively. conclusions in general, results showed that maize-peanut intercropping could be profitable due to use of the available resources. it can be concluded that intercropping was more efficient than sole cropping especially this is the way to make better use of resources and increase efficiency compared with sequential planting species.