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Study on the effect of available phosphorus (P) in soil on efficiency of arbuscular mycorrhizal (AM) fungi, Glomus intraradices consisted of 2 experiments. The experiment 1 was to study effect of available P level in soil on efficiency of AM fungi. It was conducted in 3 x 2 factorial in CRD with 5 replications. Factor 1 was different levels of available P in soil (low, medium and high). Factor 2 was AM fungi (with or without). Corn was grown with chemical fertilization at the recommendation rate without applying P fertilizer. The results showed that efficiency of AM fungi on growth, yield and P uptake of corn and AM colonization were highest in soil with low level of available P. However, efficiency of AM fungi on growth, yield and P uptake of corn and AM colonization were lowest in soil with high level of available P. The experiment 2 was to study effect of the P fertilizer rate on efficiency of AM fungi. It was conducted in 3 x 2 factorial in CRD with 5 replications. Factor 1 was P fertilization; nil P, half rate of P fertilizer and recommendation rate of P fertilizer. Factor 2 was AM fungi (with or without). The results showed that efficiency of AM fungi on growth, yield and P uptake of corn and AM colonization were highest when no P fertilizer and P fertilizer applying at half rate, but the efficiency and AM colonization were lowest when P fertilizer applying at the recommendation rate. Therefore, these results indicated that available P in soil affected the efficiency of AM fungi. The highest of efficiency of AM fungi was shown in low available P in soil and no P fertilizer applying or at half rate of P fertilizer. In contrast, the lowest efficiency of AM fungi was shown in high available P in soil or P fertilizer applying at the recommendation rate.
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