Rational Phosphorus Application Facilitates the Sustainability of the Wheat/Maize/Soybean Relay Strip Intercropping System

• Published in: PloS one Vol. 10; no. 11; p. e0141725
• Main Authors: Chen, Yuanxue, Zhou, Tao, Zhang, Chaochun, Wang, Ke, Liu, Jing, Lu, Junyu, Xu, Kaiwei
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 05.11.2015; Public Library of Science (PLoS)
• Subjects: Agricultural management; Agricultural practices; Agriculture; Agriculture - methods; Agrochemicals; China; Corn; Crop yield; Crops, Agricultural - chemistry; Crops, Agricultural - metabolism; Edible Grain - chemistry; Edible Grain - metabolism; Efficiency; Eutrophication; Experiments; Fertilizers; Field tests; Glycine max; Glycine max - chemistry; Glycine max - metabolism; Grain; Intercropping; Leaching; Legumes; Nitrogen; Nitrogen - metabolism; Nutrition; Outdoor air quality; Phosphorus; Phosphorus - chemistry; Phosphorus - metabolism; Pollution; Pollution sources; Productivity; Relay; Science; Soil - chemistry; Soybeans; Sun; Sustainability; Sustainable agriculture; Triticum - chemistry; Triticum - metabolism; Triticum aestivum; Wheat; Zea mays - chemistry; Zea mays - metabolism
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0141725

Wheat (Triticum aestivum L.)/maize (Zea mays L.)/soybean (Glycine max L.) relay strip intercropping (W/M/S) system is commonly used by the smallholders in the Southwest of China. However, little known is how to manage phosphorus (P) to enhance P use efficiency of the W/M/S system and to mitigate P leaching that is a major source of pollution. Field experiments were carried out in 2011, 2012, and 2013 to test the impact of five P application rates on yield and P use efficiency of the W/M/S system. The study measured grain yield, shoot P uptake, apparent P recovery efficiency (PRE) and soil P content. A linear-plateau model was used to determine the critical P rate that maximizes gains in the indexes of system productivity. The results show that increase in P application rates aggrandized shoot P uptake and crops yields at threshold rates of 70 and 71.5 kg P ha-1 respectively. With P application rates increasing, the W/M/S system decreased the PRE from 35.9% to 12.3% averaged over the three years. A rational P application rate, 72 kg P ha-1, or an appropriate soil Olsen-P level, 19.1 mg kg-1, drives the W/M/S system to maximize total grain yield while minimizing P surplus, as a result of the PRE up to 28.0%. We conclude that rational P application is an important approach for relay intercropping to produce high yield while mitigating P pollution and the rational P application-based integrated P fertilizer management is vital for sustainable intensification of agriculture in the Southwest of China.