Mixed cropping with duck co-culture: an agroecological system to improve grain quality and farm profitability

BACKGROUND: Previous studies found that mixed cropping combined with duck co-culture (MCDC) system could improve the efficiency of grain production and positively affect soil nutrient contents. However, the effects on grain quality, and profitable income have not been evaluated yet. In this study, a field experiment with four combinations of different rice varieties and ducks was conducted during both the early and late rice growing seasons. RESULTS: The field survey demonstrated that MCDC system significantly decreased the grain appearance of chalky rice rate and the chalkiness degree with an average of 56.82%, and 54.28%, respectively. Leaf SPAD value, photosynthetic rate, and aboveground dry weight were all improved in the MCDC and mixed-cropping systems, relative to the mono-cropping system. The net income obtained from the mono-cropping, mixed cropping (no ducks), and MCDC (with ducks) systems (from grain and ducks' meat) was 581.2 USD ha⁻¹ yr⁻¹, 1001.8 USD ha⁻¹ yr⁻¹, and 5242.1 USD ha⁻¹ yr⁻¹ in both growing seasons, respectively. CONCLUSION: Planting genetically diverse rice varieties and co-culture with ducks increased rice growth rates, productivity and grain quality. The MCDC system would provide more ecological and economic benefits compared with the conventional mono-cropping system.