Table 2.

F-values from three-way repeated measures ANOVA on the effects of potassium rate (K0, K50, K100, K150, and K250), shading treatment (no shading, shading 10 days after anthesis) and different sampled time (10 and 15 days after anthesis) on leaf SPAD, chlorophyll fluorescence parameters, grain soluble sugar content, sheath and stem fructan content.

Variation	d.f.	SPAD	F0	qP	qN	ETR	GSSC	ShFC	StFC
K application rate (K)	4	113.7**	162.5**	187.4**	2740.7**	745.9**	296.4**	179.8**	102.2**
Shading (S)	1	337.4**	1320.2**	167.9**	919.5**	3149.3**	3341.5**	1102.5**	1718.1*
Time (T)	1	1921.7**	9.8**	524.7**	730.5**	652.1**	2186.6**	122.7**	266.9*
K × S	4	42.2**	75.4**	3.2*	221.4**	63.8**	92.5**	58.3**	33.0**
K × T	4	4.3**	10.8**	133.5**	31.3**	154.1**	18.5**	3.7*	65.0**
S × T	1	33.3**	109.8**	0.1NS	256.3**	180.3**	259.1**	33.8**	563.6**
K × S × T	4	1.0NS	34.7**	5.8**	31.3**	18.7**	9.8**	4.2**	22.5**

*, ** represent the test significant at the 5% level (P < 0.05) and 1% level (P < 0.01), respectively; NS, test non-significant at the 5% level. GSSC, Grain soluble sugar content; ShFC, Sheath fructan content; StFC, Stem fructan content.