Factors related water and dry matter during pre- and post- heading in four millet species under severe water deficit

Figures & data

Table 1. Influence of the water deficit on grain yield and yield components in four millet species.

Spicies	Treatment	DSI	Days^1)	Grain yield per plant (g plant-1)	Panicle number per plant	Grain number per panicle	1000-grain weight (g)	Total dry weight (g plant-1)	Harvest index
S.italica	C	0.62 a	110	31.3 a	1 a	13889 a	2.5 a	98.6 a	0.32 ab
	CLA0.5		113	33.1 a	1 a	14073 a	2.5 a	91.9 a	0.36 a
	CLA0		116	5.1 c	1 a	2210 c	2.3 a	36.2 c	0.14 c
	D		120	19.5 b	1 a	10387 b	2.4 a	66.8 b	0.29 b
	DLA0.5		116	20.6 b	1 a	9340 b	2.4 a	59.9 b	0.34 ab
	DLA0		113	3.8 c	1 a	1749 c	2.2 a	25.8 d	0.15 c
P.miliaceum	C	0.85 a	92	28.6 a	3 a	2113 a	4.5 a	80.7 a	0.35 a
	CLA0.5		95	25.1 a	3 a	1758 a	4.4 a	72.0 a	0.35 a
	CLA0		102	4.5 c	3 a	509 c	3.6 a	26.7 b	0.17 b
	D		99	13.6 b	2 a	1469 ab	4.1 a	36.6 b	0.37 a
	DLA0.5		101	11.8 b	4 a	867 bc	4.2 a	33.2 b	0.36 a
	DLA0		101	2.3 c	4 a	226 c	3.8 a	14.1 c	0.17 b
S.glauca	C	1.22 b	125	20.8 a	128 a	76 b	2.1 a	131.1 a	0.16 b
	CLA0.5		120	18.2 a	84 b	99 a	2.2 a	97.0 b	0.19 a
	CLA0		120	11.6 b	85 b	64 b	2.2 a	74.3 c	0.16 b
	D		124	6.4 c	139 a	25 d	1.9 a	69.2 cd	0.09 c
	DLA0.5		124	6.6 c	78 bc	44 c	2.0 a	62.7 cd	0.11 c
	DLA0		124	2.9 d	65 c	25 d	1.9 a	57.7 d	0.05 d
P.sumatrense	C	1.34 b	126	24.4 a	41 a	241 a	2.5 a	117.5 a	0.21 a
	CLA0.5		126	24.4 a	36 ab	278 a	2.5 a	106.8 b	0.23 a
	CLA0		124	16.0 b	23 b	300 a	2.4 a	81.9 c	0.20 a
	D		140	5.8 c	35 ab	92 b	1.9 b	53.2 d	0.11 b
	DLA0.5		140	5.4 c	28 ab	105 b	2.0 b	52.6 d	0.10 b
	DLA0		140	1.7 d	21 b	39 b	2.1 b	40.2 e	0.04 c
ANOVA
Crop				**	**	**	**	**	**
Treatment				**	**	**	**	**	**
Crop×Treatment				**	**	**	**	**	**

**: mean significant at p < 0.01. Different small letters in the same column in each species show significance at p < 0.05 by Turkey-Kramer multiple range test. 1) Days to harvesting from the onset of the dehydration treatment.

C: control treatment at 40% soil water content; CLA0.5: half of the leaf area per plant was removed in the control treatment at heading; CLA0: all leaves were removed in the control treatment at heading; D: dehydration treatment, which was 20% soil water content from 25 d after sowing until harvest; DLA0.5: half of the leaf area per plant was removed in the dehydration treatment at heading; DLA0: all leaves were removed in the dehydration treatment at heading; DSI: drought susceptibility index.

Figure 1. Relationships between grain yield and yield components in four millet species.

** and * indicate significant correlations at 1 and 5%, respectively. ^NS, no significant correlation.

Table 2. Effects of the dehydration treatment on leaf water potential (ΨL), leaf osmotic potential (πL) at full turgor, and leaf osmotic adjustment (OA) at 20 d after the initiation of the drought treatment.

Species	Treatment	ΨL	πL	OA
S.italica	C	-0.85	-1.33	0.06 b
	D	-2.02 **	-1.39 ^NS
P.miliaceum	C	-0.87	-1.34	0.20 ab
	D	-1.72 **	-1.54 ^NS
S.glauca	C	-0.80	-1.35	0.45 a
	D	-1.80 **	-1.80 *
P.sumatrense	C	-1.12	-1.27	0.28 ab
	D	-1.90 **	-1.55 ^NS
ANOVA
Crop		**	NS	－
Treatment		**	**	－
Crop×Treatment		**	NS	－

**: Significant at p < 0.01. *: Significant at p < 0.05. ^NS: not significant.

C: control treatment; D: dehydration treatment.

Table 3. Influence of the dehydration treatment on transpiration, water use efficiency (WUE) and yield WUE in four millet species.

Species	Treatment	Transpiration (L plant^−1)			WUE (g L^−1)			Yield WUE (g L-1)
		Heading	Harvest	Total	Heading	Harvest	Total
S.italica	C	3.9	13.7	17.6	8.72	4.62	5.60	2.28
	D	3.3 *	7.1 **	10.4 **	10.21 *	5.85*	6.42^NS	2.75**
P.miliaceum	C	2.3	11.0	13.2	9.22	5.46	6.09	2.59
	D	1.2 **	4.8 **	5.9 **	11.04 **	5.75^NS	6.16^NS	2.87*
S.glauca	C	4.4	17.7	22.0	11.44	5.30	5.95	1.17
	D	4.2 ^NS	7.0 **	11.6 **	7.70 **	5.26^NS	5.95^NS	0.91*
P.sumatrense	C	7.4	11.9	19.4	7.50	4.95	6.08	2.04
	D	5.7 **	3.6 **	9.3 **	8.98 **	6.29*	6.37^NS	1.64*
ANOVA
Crop		**	**	**	**	**	NS	**
Treatment		*	**	**	**	**	NS	**
Crop×Treatment		*	**	**	**	**	NS	**

**: Significant at p < 0.01. *: Significant at p < 0.05. NS: not significant.

C: control; D: dehydration treatment.

Table 4. Influence of the dehydration treatment on the NSC content of the stem, including leaf sheath, the increase in total dry weight (ΔTDW), the increase in the panicle dry weight (ΔP), the dry matter partitioning ratio (DMPR) in four millet species.

Species	Treatment	NSC (mg g^−1 DW)	ΔTDW1 (g plant^−1)	ΔTDW2 (g plant^−1)	ΔP (g plant^−1)	DMPRS	DMPRP
S.italica	C	316.6	6.19	63.5	35.4	0.23	0.56
	D	480.8 **	4.78 *	41.6 *	23.1 **	0.16 *	0.56 ^NS
P.miliaceum	C	276.2	3.81	60.2	35.4	0.30	0.59
	D	349.3 *	1.42 **	27.3 *	16.8 *	0.24 *	0.62 ^NS
S.glauca	C	319.8	5.68	93.9	31.2	0.49	0.33
	D	373.2 ^NS	5.52 ^NS	36.9 **	9.8 **	0.53 ^NS	0.27 *
P.sumatrense	C	388.3	7.47	59.2	32.4	0.32	0.55
	D	336.1 ^NS	4.23 **	22.6 **	9.9 **	0.35 ^NS	0.44 *
ANOVA
Crop		**	**	**	**	**	**
Treatment		**	**	**	**	*	*
Crop×Treatment		**	NS	**	**	NS	*

** Significant at the 0.01 probability level. * Significant at the 0.05 probability level.

NS not significant. C, control; D, dehydration treatment.