Table 4.

Effects of heat priming and post-anthesis heat stress on the green flag leaf area (cm² stem^-1) of Yangmai 18 and Yannong 19 at the grain-filling stage from 2015 to 2017.

Cultivar	Treatment	15 DAA	20 DAA	25 DAA
2015-2016
Yangmai 18	NN	25.60 a	21.12 a	16.65 a
	NH	25.60 a	17.27 c	8.14 d
	P SH	25.18 a	18.66 b	10.83 b
	P BH	25.66 a	19.11 b	11.48 b
	P AH	24.84 a	17.86 bc	9.61 c
Yannong 19	NN	20.44 b	18.59 b	11.55 b
	NH	20.44 b	14.67 d	5.65 g
	PSH	20.67 b	15.56 d	7.84 de
	PBH	20.27 b	15.76 d	6.92 ef
	PAH	19.72 b	14.64 d	6.12 fg
2016-2017
Yangmai 18	NN	26.79 ab	21.66 a	16.95 a
	NH	26.79 ab	17.45 cd	9.03 de
	P SH	27.35 a	19.26 b	10.03 cd
	P BH	26.86 ab	18.40 bc	10.90 bc
	P AH	25.79 b	18.03 bc	8.63 e
Yannong 19	NN	21.39 c	19.06 b	11.76 b
	NH	21.39 c	14.70 f	5.13 g
	PSH	21.73 c	15.45 ef	6.10 fg
	PBH	20.33 d	16.42 de	6.80 f
	PAH	19.64 d	14.81 f	5.42 e
F-value	F-Y ear(Y)	38.684∗∗	1.103	4.989∗
	F-Cultivar(C)	1238.967∗∗	236.204∗∗	464.572∗∗
	F-Treatment(T)	8.037∗∗	57.793∗∗	205.213∗∗
	F-Y × C	5.924∗	0.056	0.881
	F-Y × T	1.752	0.217	2.646∗
	F-C × T	1.055	0.874	4.182∗∗
	F-Y × C × T	0.463	0.818	0.995

NN refers to no heat priming + no heat stress at the grain-filling stage (control); NH refers to no heat priming + heat stress at the grain-filling stage; P_SH refers to heat priming at the stem-elongation stage + heat stress at the grain-filling stage; P_BH refers to heat priming at booting + heat stress at the grain-filling stage; P_AH refers to heat priming at anthesis + heat stress at the grain-filling stage. F_{Y × C}, F_{Y × T}, F_{C × T}, and F_{Y × C × T} refer to F-values for interactions of year with cultivar, year with treatment, cultivar with treatment, year with cultivar and treatment, respectively. ^∗ and ^∗∗ indicate significant differences at the 0.05 and 0.01 levels, respectively. The data are means ± SE (n = 3). Lowercase letters following the data within the same column refer to significant differences (P < 0.05).