Responses of rice (Oryza sativa L.) growth and yield to phosphogypsum amendment in saline-sodic soils of North-East China.

摘要

Salinity and alkalinity are important limitations for agricultural production in semi-arid region. A plot experiment was conducted on a saline-sodic soil to investigate the effects of phosphogypsum amendment on growth, yield and yield components of two rice (Oryza sativa L.) cultivars (Dongdao 2 and Changbai 9) in 2009. The amelioration treatments were highly saline-sodic soil (control), phosphogypsum added at rate of 151 ha-1, 301 ha-1 and 45 t ha-1, which are referred to as PG1, PG2 and PG3, respectively. Results from the study show that the application of phosphogypsum increased grain yield of the both rice cultivars significantly. Average increment in yield was 1.12, 2.47 and 2.981 ha-1 for PG1, PG2 and PG3 against control, but there was no significant difference between PG2 and PG3. With increasing phosphogypsum levels from PG1 to PG3, the yield components increased significantly. Generally, the increment was 124%, 133% and 202% for individual grain mass m-2, 1182%, 3058% and 4235% for spikelets m-2, 161%, 191% and 246% for panicles m-2, 153%, 271% and 343% for filled spikelet percentage, and 4%, 17% and 21% for 1000-grain weight in PG1, PG2 and PG3 compared with the control. PG2 gave similar results to PG3 in terms of grain yield and yield components. We suggest that phosphogypsum added at rate of 30 t ha-1 should be adopted in saline-sodic soils of North-East China.