Crop residue incorporation combined with potassium fertilizer increased cotton canopy apparent photosynthesis and seed cotton yield in barley-cotton rotation system

The field experiment was conducted to evaluate the effects of crop residue incorporation and K fertilizer on seed cotton yield, K uptake and canopy apparent photosynthesis. Without K fertilizer, barley residue incorporation and barley-cotton residue incorporation increased seed cotton yield, total biomass, K uptake, leaf K concentration, leaf area index and canopy apparent photosynthesis in 2017 and 2018, while cotton residue incorporation increased these factors in 2018; and with 150 kg ha(-1) K2O, barley residue incorporation and barley-cotton residue incorporation increased K uptake and leaf K concentration in 2017 and 2018, while these factors were influenced by cotton residue incorporation in 2018. Thus, the effects of crop residue incorporation on cotton growth depended on K fertilizer rate. In addition, crop residue incorporation could reduce K fertilizer input to some extent. Based on yield, barley residue incorporation and barley-cotton residue incorporation could reduce 73.7 kg ha(-1) K2O (49.1%) and 70.1 kg ha(-1) K2O (46.7%) in 2017, 53.6 kg ha(-1) K2O (35.7%) and 89.5 kg ha(-1) K2O (59.6%) in 2018, while cotton residue incorporation could reduce 38.0 kg ha(-1) K2O (25.4%) in 2018.

Automated summary

The incorporation of crop residues into the soil had positive effects on cotton growth and yield, especially when no potassium fertilizer was applied, significantly increasing various indicators. The impact of different residue incorporation methods on cotton growth depended on the rate of potassium fertilizer application, and incorporating crop residues could reduce the amount of potassium fertilizer needed.