In Vietnam, 4 trials in total on spring and summer rice, grown on a heavy and a sandy soil, were conducted with 1, 2 or 3 foliar applications each containing 9 kg KNO₃/ha/spray, applied at one or more growth stages (active tillering, panicle initiation and/or end of flowering), in order to test the effect on yield and farmers’ net income.  

The highest increases in average yield (+15%; + 840 kg/ha) and average farmers’ net income (+13%; + 150 US$/ha) were obtained with 3 foliar sprays of 9 kg KNO₃/ha/spray each at the growth stages of active tillering, panicle initiation and end of flowering in combination with a standard base dressing, compared to the farmers’ standard practices.

Interestingly enough, 50% less KCl applied in the base dressing, in combination with 3 foliar sprays of 9 kg KNO₃/ha/spray each at active tillering, panicle initiation and end of flowering, resulted in 10% more yield and 12% more farmers’ net income, compared to the farmers’ standard practices.

For more information, click: PUBLICATIONS PNA trial reports