Impact of cobalt application to soil and mycorrhizal fungi inoculation on growth and some nutrients content of barley and Egyptian clover plants grown in calcareous soil

Abstract

Two pot experiments were carried out at the green-house of Faculty of agriculture (Saba Bash), Alexandria University to study the effect of addition of cobalt to the soil in form of cobalt sulphate by preparing six different concentrations, (0.0, 10, 20, 40, 80, and 160 mg of cobalt/ kg soil) in relation to two species of mycorrhiza inoculation each alone (G. intraradiaces and G. macrocarpium) on growth and quality of barely and clover as forage crops under calcareous soil conditions during 2012-2013 and 2013-2014 growing seasons, respectively. Experimental design was randomized complete block design (R.C.B.D) with one hundred and eight experimental units and three replicates. The study was carried out, by planting the seeds in plastic pots in glass houses. After the appearance of three leaves, the pots were irrigated once only by each particular concentration, of cobalt. The obtained results showed that addition of cobalt to the soil of barley and clover (forage crops) and mycorrhizal inoculation had significant effects on all growth parameters and the tested nutrients content in the plants of the two crops. The Co significantly increased the contents of N, P, K, and Co in shoot and root of the tested plants. It was found that G. intraradiaces was more effective than G. macrocarpium for the studied traits. Also, the recommended cobalt concentration for barley crops was lower 20 mg/l) than that for E.Clover (40mg/l). However, Co concentration above 20 and 40 mg/kg soil for barley and E. Clove, respectively, reduced growth of plants.