Quantitation of PMQR genes in soils Total
The study was conducted using soil samples from a long-term field experiment, which was established at Shenyang City, Liaoning Province, northeast China (41°32′ N, 123°23′ E) in 2002. The area belongs to the temperate sub-humid mainland climate. The mean annual temperature is 7.5 °C. The average annual precipitation per year is 680 mm. The frost-free Verteporfin is 147–164 days. The soil is classified as Luvisol (FAO, 2006). Four treatments were involved in the present study: no fertilizer control (CK), low swine manure rate (ML), middle swine manure rate (MM), and high swine manure rate (MH), which are equivalent to 0, 100, 250, and 500 kg total N ha− 1 year− 1 from 2002 to 2008, and 0, 10, 25 and 50 t fresh weight ha− 1 year− 1 from 2009 to 2013, respectively. No other fertilizers were added to ovule field. Each treatment was laid out in a randomized block design with three replicates (plots). Swine manure was stored for about four months prior to land application and spread just prior to sowing (about early May). Irrigation and herbicides were not applied, and weeds were removed by hand hoeing.