the effects of corn (zea mays) and green gram (vigna radiata) intercropping on yield, ler and some quality characteristics of forage

this experiment was carried out to study the effects of corn and green gram intercropping on yield and some quality characteristics of forage at agricultural research station of gorgan during summer 2006 & 2007. the experimental design was a randomized complete block design (rcbd) with twelve treatments and four replications. a local green gram and corn single cross 550 were the crops used in the experiment. the experimental treatments consisted of sole corn and sole green gram either with or without weed control, corn + 10%, 20%, 30%, 40% and 50% green gram in additive series of intercropping system, and 25, 50 and 75% green gram in place of corn in replacement series. the results showed that differences between the two years concerning dry matter digestible (dmd), crude protein (cp), ash (? = 0.01) and water soluble fiber (wsc) (? = 0.05) were significant. in year 2007, forage dry weight, dmd, wsc, and ash were greater and cp, acid detergent fiber (adf) and protein yield were lower than in 2006. differences among all characteristics of intercropping (forage dry weight, dmd, cp, wsc, adf, ash and protein yield) were significant (? = 0.01). interactions of year×intercropping regarding forage dry weight (? = 0.05) and protein yield (? = 0.01) were significant. the most forage dry weight (14.88 ton), dmd (78.14 percent), and wsc (32.41 percent) were obtained from weed controlled sole corn. maximum protein (18.63 percent) and ash (8.8 percent) were obtained from sole green gram accompanied by weed control. maximum adf (26.88 percent) belonged to sole green gram of no weed control. maximum protein yield (1.42 ton) belonged to corn + 50% green gram. minimum forage dry weight (4.32 ton), dmd (66.36 percent), wsc (17 percent) and protein yield (0.8 ton) belonged to sole cropping of green gram without any weed control. maximum protein (18.63 percent) was obtained from sole corn accompanied by weed control. minimum adf (17.81 percent) and ash (4.27 percent) belonged to weed controlled to sole corn crop. the most appropriate treatment was finally decided as corn + 50% green gram