Biochar and mycorrhizal fungi influence on nutrient uptake by two pasture species in new zealand

Abstract

The symbiotic relationship between plants and mycorrhizal fungi can play an important role in enhancing nutrient uptake from the soil. Many New Zealand farm soils have elevated levels of phosphorus because of regular, long term, application of phosphate fertiliser. Much of this phosphate is not available to plants. This study aimed to investigate the effect of biochar on mycorrhizal growth and subsequent phosphorus uptake by white clover and ryegrass. The experiment was conducted in a 3×2×2 factorial design, including two biochar produced from pine at different final pyrolysis temperature (350 and 550°C), mycorrhizal inoculation (Glomus sp. arbuscular mycorrhiza) and phosphate rock, respectively. The soil sample was provided from the 10cm surface horizon of an Egmont black loam. The pots were filled with the soil sample mixed with biochar applied at 10 tha -1 .Phosphate rock was applied at a rate of 70 kg ha -1 . The seeds were inoculated by Glomus sp. arbuscular mycorrhizae before sowing. The ryegrass also contained the endophyte, AR37. Dry weight, phosphorus and nitrogen concentrations of plant tissue were measured68 days after sowing. There was an increase in both phosphorus uptake and dry weight in plants grown with the high temperature biochar (B550). There was significant increase in phosphorus uptake and herbage yield in clover plants if inoculated by mycorrhizal fungi. The results demonstrated that biochar have the potential to affect the nutrients in soil and microbial activity.