Table 3.

Tuber yield, aboveground biomass, total biomass, harvest index, and tuber mass distribution (means ± SE) of the potatoes grown under four different thermal regimes at TI and TB.

Growth stage	Thermal regime	Tuber yield (g DM plant-1)	Aboveground biomass (g DM plant-1)	Total biomass (g DM plant-1)	Harvest index	Yield proportion
						Small	Medium	Large
TI	Control	78.1 ± 4.9 a	37.9 ± 7.1 b	115.9 ± 10.7	0.68 ± 0.04 a	0.35 ± 0.08	0.24 ± 0.04	0.41 ± 0.12 a
	HNT	64.6 ± 6.8 b	47.7 ± 5.2 a	112.4 ± 7.7	0.57 ± 0.04 b	0.48 ± 0.07	0.33 ± 0.08	0.19 ± 0.05 b
	HDT	63.9 ± 6.0 b	35.1 ± 2.7 b	99.0 ± 7.7	0.65 ± 0.02 a	0.34 ± 0.10	0.26 ± 0.01	0.40 ± 0.10 a
	HDNT	54.4 ± 2.5 b	48.1 ± 2.7 a	102.5 ± 2.8	0.52 ± 0.03 c	0.49 ± 0.10	0.29 ± 0.09	0.22 ± 0.03 b
	Significance	∗	∗	ns	∗∗∗	ns	ns	∗
TB	Control	82.3 ± 2.3	43.7 ± 2.3	126.0 ± 4.2	0.66 ± 0.01	0.31 ± 0.03	0.38 ± 0.01	0.31 ± 0.04
	HNT	84.3 ± 2.4	42.6 ± 0.6	126.8 ± 2.3	0.66 ± 0.01	0.36 ± 0.04	0.37 ± 0.10	0.28 ± 0.06
	HDT	89.7 ± 13.4	46.9 ± 6.4	136.6 ± 19.7	0.65 ± 0.01	0.33 ± 0.02	0.41 ± 0.04	0.27 ± 0.04
	HDNT	83.4 ± 3.4	47.3 ± 6.2	130.7 ± 9.2	0.64 ± 0.02	0.32 ± 0.03	0.33 ± 0.04	0.35 ± 0.06
	Significance	ns	ns	ns	ns	ns	ns	ns

Yield proportion is determined as tuber yield (FM) of each mass class over total tuber yield (FM). Small, medium, and large represent tuber mass classes of 1–50, 50–100, and >100 g, respectively. ^∗p < 0.05, ^∗∗∗p < 0.001, and ns, non-significant, respectively. Within each growth stage, the same letters in a column are not significantly different, as analyzed by LSD test at the 0.05 probability level.