Table 1. Effect of different K application levels on the disease index (DI) of soybean cyst nematode and cyst nematode number (CNN) in the two field trials over two years.

Year	K treatment	Zhangjiachi		Changling
		DI	CNN	DI	CNN
	K0	85±4a	76±7a	52±3a	52±4a
2012	K60	66±2b	50±6b	36±2b	33±4b
	K120	69±2b	56±3b	38±2b	37±6b
	K0	77±2a	82±5a	56±3a	66±4a
2013	K60	57±3b	61±6b	42±4b	48±6b
	K120	62±3b	63±6b	42±3b	53±5b

Note: Disease index and cyst nematode number were measured as described in the Materials and Methods. K0, no K application; K60, 60 kg ha^-1 K; K120, 120 kg ha^-1 K. All of the data are the means ± SE (n = 4). The different letters after the numbers in the same column for the same trait in the same year indicate significant differences (P<0.05) by Duncan’s t-tests.