Effect of biochar addition on physicochemical properties of nursery soil and traits of rice seedlings

Objective  To understand the potential use of biochar in rice seedling nursery.

Method  Cassava straw biochar was used to determine the effects of biochar addition (φ=25%) on physicochemical properties of nursery soil, and root and shoot traits of rice seedlings under different sowing dates.

Result  Compared with control, cassava straw biochar improved the physicochemical properties of nursery soil, with bulk density decreased by 0.66 g·cm^–3, pH, organic matter and alkalized nitrogen contents increased by 0.51, 50 mg·cm^–3 and 195 μg·cm^–3respectively. Besides, with the addition of cassava straw biochar, length, surface area, volume and biomass of root system and rooting ability increased by 32.4%, 30.1%, 50.0%, 13.7% and 21.5% respectively, and leaf area, plant height, basal stem width and aerial biomass of seedlings increased by 19.2%, 8.0%, 5.3% and 10.2% respectively. The effect of biochar addition on rice seedling traits varied with sowing date. Biochar had significant effect on seedling traits on the sowing date under relatively lower temperature.

Conclusion  Biochar can improve the quality of rice seedlings, especially under relatively low temperature conditions. Biochar is a kind of beneficial additive of rice nursery soil.