evaluation of radiation absorption and radiation use efficiency of intercropping of sweet basil and bean

intercropping may be helpful manner to increase interception and utilization. the aim of this study was to compare radiation use efficiency and radiation interception in intercropping with sole cropping. an experiment was conducted at the agricultural research station, ferdowsi university of mashhad in the growing season of the year 2008. the experimental treatments were: 1- sole crop of bean 2- sole crop of sweet basil 3- strip intercropping of bean and sweet basil (four row bean and two row sweet basil) 4- strip intercropping of bean and sweet basil (two row sweet basil and four row bean) 5- row intercropping of bean and sweet basil. for this purpose a complete randomized block design with 3 replications was used. for analysis crop radiation capture and utilization, three indices are often used: the fraction of radiation intercepted (f), harvest index (hi) and radiation use efficiency (rue). results showed that the intercrop f was higher than the sole crop f and there was no difference hi among treatments. rue of sweet basil in intercrop treatments was increased compared to sole crop and highest rue of sweet basil obtained in row intercropping (3.2g/mj), rue of bean decreased in intercrop treatments and highest rue of bean obtained in sole crop bean (2.03g/mg). light extinction coefficient of bean was obtained 0.55 and sweet basil 0.47. the highest leaf area index (lai) in bean was obtained in sole crop (4.3) and the highest lai in sweet basil was in strip inter cropping with 4 row sweet basil.