Drought tolerance screening of maize accessions at early growth stage in the mid-hills of Nepal

Figures & data

Table 1. List of local maize accessions collected from NAGRC, Khumaltar.

Treatment	Name of accessions
1	NGRC05561	17	NGRC05578
2	NGRC05562	18	NGRC05581
3	NGRC05563	19	NGRC05582
4	NGRC05564	20	NGRC05583
5	NGRC05565	21	NGRC05584
6	NGRC05566	22	NGRC05585
7	NGRC05568	23	NGRC05586
8	NGRC05569	24	NGRC05587
9	NGRC05570	25	NGRC05588
10	NGRC05571	26	NGRC05589
11	NGRC05572	27	NGRC05590
12	NGRC05573	28	NGRC05591
13	NGRC05574	29	NGRC05592
14	NGRC05575	30	NGRC05593
15	NGRC05576

Table 2. ANOVA for nine quantitative traits.

S. n	Traits	Mean sum of squares
		Condition	Accessions	Condition*accessions
		(D.F. = 1)	(D.F.= 29)	(D.F. =29)
1	Root length	37,713***	673***	536***
2	Shoot length	6478.3***	269***	462.6***
3	Root:shoot ratio	0.0022*	0.0012**	0.0006 ^ns
4	Number of roots	221.408***	23.784*	9.598 ^ns
5	Root moisture content	1716.03***	8.48 ^ns	8.95*
6	Shoot moisture content	474.8***	7.12 ^ns	12.57**
7	Relative water content	0.136***	0.016***	0.07 ^ns
8	Root volume	6.816 ^ns	15.97***	21.07***
9	NDVI	0.589***	0.001*	0.0008 ^ns

Note: ns: non-significant.

*Significant at 5% level.

**Significant at 1% level.

***Significant at 0.1% level.

Figure 1. Interaction of 30 maize accessions with error bars representing standard error for the trait ‘shoot length’ under irrigated (SL_I) and drought (SL_D) conditions. Interaction is significant at p ≥ .001.

Table 3. Mean separation table for nine quantitative traits in 30 maize accessions.

Factor A: accessions
Accessions	RL	SL	R:S	NoR	RMC	SMC	RWC	RV	NDVI
NGRC05561	43.95^a–f	108.25^ab	0.062^bcd	12.25^bcd	7.66^b–e	8.09^a–d	0.448^g	5.13^b–f	0.653^b–f
NGRC05562	51.75^ab	101.05^abc	0.080^bc	16.25^abc	6.92^cde	8.79^a–d	0.492^fg	6.75^bc	0.675^abc
NGRC05563	38.875^b–j	112.1^a	0.063^bcd	16.75^abc	7.68^b–e	9.31^a–d	0.490^fg	3.83^e–j	0.678^ab
NGRC05564	43.225^a–g	97.875^a–d	0.070^bcd	15.25^abcd	7.92^b–e	7.77^bcd	0.503^fg	4.65^c–h	0.625^f
NGRC05565	51.725^ab	104.7^ab	0.123^a	15^a–d	11.16^ab	8.93^a–d	0.551^d–g	6.88^bc	0.663^a–f
NGRC05566	48.45^a–d	106.425^ab	0.082^b	18.75^a	8.06^a–e	8.67^a–d	0.575^c–f	7.38^b	0.675^abc
NGRC05568	31.625^f–k	106.875^ab	0.050^bcd	16^abc	8.18^a–e	9.95^a–d	0.547^efg	3.63^e–k	0.653^b–f
NGRC05569	36.075^d–k	104.375^ab	0.067^bcd	15.5^a–d	8.09^a–e	8.33^a–d	0.570^c–g	4.03^d–j	0.668^a–e
NGRC05570	49.9^abc	93.875^b–g	0.063^bcd	10^d	11.96^a	10.24^a–d	0.558^c–g	3.50^e–k	0.673^a–d
NGRC05571	41.3^a–h	107.525^ab	0.070^bcd	18^ab	7.94^bcde	7.91^bcd	0.754^a	5.38^b–e	0.658^a–f
NGRC05572	38.6^b–j	108.975^ab	0.059^bcd	16.5^abc	7.16^b–e	8.26^a–d	0.675^abc	4.28^d–i	0.653^b–f
NGRC05573	27.175^ijk	78.5^gh	0.042 ^cd	10^d	8.29^a–e	11.96^a	0.673^a–d	1.33^k	0.665^a–f
NGRC05574	47.875^a–e	97.025^a–f	0.057^bcd	15.5^a–d	7.15^b–e	9.02^a–d	0.506^fg	3.00^e–k	0.658^a–f
NGRC05575	29.1^h–k	97.6125^a–e	0.043^bcd	18.75^a	9.11^a–e	9.04^a–d	0.566^c–g	2.43^h–k	0.635^c–f
NGRC05576	25.85^jk	75.2^h	0.032^d	12.25^bcd	6.61^cde	10.28^a–d	0.606^b–f	2.30^h–k	0.648^b–f
NGRC05577	29.6^g–k	83.425^d-h	0.057^bcd	12.25^bcd	7.02^cde	9.33^a-d	0.538^efg	3.03^e-k	0.645^b-f
NGRC05578	35.25^d-k	72.2^h	0.040^d	13.75^a-d	9.10^a-e	10.51^a-d	0.585^b-f	2.13^i-k	0.643^b-f
NGRC05581	32.775^f-k	82.475^d-h	0.052^bcd	12.75^bcd	10.01^abc	8.15^a-d	0.599^b-f	2.60^g-k	0.65^b-f
NGRC05582	28.225^h–k	80.725^d–h	0.035^d	11^cd	8.73^a–e	10.86^abc	0.569^c–g	1.63^jk	0.64^b–f
NGRC05583	23.6^k	79.675^fgh	0.035^d	13.25^a–d	9.36^a–d	9.04^a–d	0.597^b–f	1.65^jk	0.643^b–f
NGRC05584	39.2^b–j	80.075^e–h	0.047^bcd	10^d	6.23^cde	10.24^a–d	0.598^b–f	2.88^f–k	0.65^b–f
NGRC05585	34.175^f–k	75.7^h	0.038^d	12.75^bcd	9.57^a–d	11.73^ab	0.697^ab	3.13^e–k	0.653^b–f
NGRC05586	33.05^f–k	79.775^fgh	0.056^bcd	13.5^a–d	8.77^a–e	7.99^bcd	0.651^a–e	3.25^e–k	0.633^def
NGRC05587	30.875^f–k	71.65^h	0.058^bcd	13^a–d	8.87^a–e	7.01 ^cd	0.541^efg	2.58^g–k	0.63^ef
NGRC05588	34.525^e–k	86.9^c–h	0.044^bcd	13.5^a–d	7.10^cde	8.19^a–d	0.579^b–f	3.48^e–k	0.648^b–f
NGRC05589	38.75^b–j	78^gh	0.070^bcd	12.25^bcd	7.48^b–e	8.65^a–d	0.599^b–f	4.95^c–g	0.673^a–d
NGRC05590	39.825^b–i	84.95^c–h	0.052^bcd	14^a–d	8.25^a–e	7.13 ^cd	0.571^c–g	6.20^bcd	0.665^a–f
NGRC05591	41.25^a–h	85.725^c–h	0.057^bcd	12.5^bcd	7.97^b–e	7.37 ^cd	0.582^b–f	4.85^c–g	0.655^a–f
NGRC05592	38.05^c–j	76.85^gh	0.059^bcd	12.75^bcd	5.18^e	6.61^d	0.559^c–g	5.25^b–f	0.668^a–e
NGRC05593	53.35^a	84.5^c–h	0.064^bcd	15.75^a–d	5.65^de	7.98^bcd	0.547^efg	10.38^a	0.695^a
F-test	***	***	**	*	NS	NS	***	***	*
DMRT	11.176	14.91	0.03	4.87	3.27	3.20	0.101	1.99	0.03
SEm	3.95	5.267	0.2	1.72	1.155	1.13	0.035	0.7	0.012
Factor B: watering condition
Condition	RL	SL	R:S	NoR	RMC	SMC	RWC	RV	NDVI
Irrigated	30.585^b	107.83^a	0.062^a	15.35^a	11.89^a	10.9^a	0.611^a	4.32^a	0.725^a
Drought	45.28^a	72.37^b	0.053^b	12.63^b	4.32^b	6.92^b	0.543^b	3.84^a	0.585^b
F-test	***	***	*	***	***	***	***	NS	***
DMRT	2.88	3.85	0.008	1.26	0.84	0.83	0.026	0.515	0.00879
CV (%)	20.82	11.69	28.8	24.62	28.5	25.41	12.43	24.57	3.67
SEm	1.02	1.36	0.05	0.44	0.298	0.29	0.009	0.18	0.003
Grand mean	37.92	90.1	0.0576	13.99	8.107	8.91	0.577	4.08	0.655
Interaction (A × B)	***	***	NS	NS	*	**	NS	***	NS
SEm	5.585	7.45	0.28	2.43	1.63	1.6	0.05	0.997	0.017

Figure 2. Interaction of 30 maize accessions with error bars representing standard error for the trait ‘root length’ under irrigated (RL_I) and drought (RL_D) conditions. Interaction is significant at p ≥ .001.

Figure 3. Mean performance comparison of 30 maize accessions with error bars representing standard error for the trait ‘root:shoot ratio’ under irrigated (R:S_I) and drought (R:S_D) conditions. Interaction is non-significant.

Figure 4. Mean performance comparison of 30 maize accessions with error bars representing standard error for the trait ‘number of roots’ under irrigated (NoR_I) and drought (NoR_D) conditions. Interaction is non-significant.

Figure 5. Interaction of 30 maize accessions with error bars representing standard error for the trait ‘root moisture content’ under irrigated (RMC_I) and drought (RMC_D) conditions. Interaction is significant at p ≥ .05.

Figure 6. Interaction of 30 maize accessions with error bars representing standard error for the trait ‘shoot moisture content’ under irrigated (SMC_I) and drought (SMC_D) conditions. Interaction is significant at p ≥ .01.

Figure 7. Mean performance comparison of 30 maize accessions with error bars representing standard error for the trait ‘relative water content’ under irrigated (RWC_I) and drought (RWC_D) conditions. Interaction is non-significant.

Figure 8. Interaction of 30 maize accessions with error bars representing standard error for the trait ‘root volume’ under irrigated (RV_I) and drought (RV_D) conditions. Interaction is significant at p ≥ .001.

Figure 9. Mean performance comparison of 30 maize accessions with error bars representing standard error for the trait ‘NDVI’ under irrigated (NDVI_I) and drought (NDVI_D) conditions. Interaction is non-significant.

Table 4. Relative value of tolerance (RVT) for nine quantitative traits in 30 maize accessions.

Accessions	RL	SL	R:S	NoR	RMC	SMC	RWC	RV	NDVI
NGRC05561	2.924	0.637	1.858	1.136	0.355	0.525	0.830	4.633	0.775
NGRC05562	2.561	0.691	1.422	0.831	0.208	0.340	0.988	4.583	0.791
NGRC05563	1.632	0.656	1.619	0.988	0.267	0.419	0.986	1.649	0.819
NGRC05564	2.074	0.546	0.863	0.899	0.106	0.243	0.726	1.326	0.812
NGRC05565	2.161	0.578	1.368	1.228	0.226	0.340	0.806	1.708	0.867
NGRC05566	2.364	0.655	1.015	0.842	0.338	0.359	0.745	1.696	0.777
NGRC05568	1.273	0.474	0.990	0.730	0.258	0.447	0.826	1.414	0.764
NGRC05569	1.553	0.664	0.585	1.143	0.173	0.422	0.539	2.586	0.829
NGRC05570	3.383	0.766	0.832	1.125	0.326	0.571	0.938	2.075	0.782
NGRC05571	2.078	0.558	1.441	1.133	0.263	0.359	1.030	1.289	0.865
NGRC05572	1.731	0.497	0.769	0.941	0.268	0.524	0.840	1.181	0.851
NGRC05573	2.086	0.513	1.139	0.800	0.679	0.771	0.760	0.910	0.873
NGRC05574	2.152	0.558	1.160	0.984	0.401	0.653	1.045	0.708	0.753
NGRC05575	1.465	0.414	1.149	0.937	0.445	0.554	1.048	1.241	0.814
NGRC05576	1.569	0.697	0.851	0.833	0.356	0.633	0.995	1.182	0.739
NGRC05577	1.523	0.623	1.127	0.646	0.449	0.462	0.746	0.698	0.818
NGRC05578	1.562	0.635	0.907	0.893	0.689	0.639	1.057	0.792	0.798
NGRC05581	2.227	0.757	1.086	0.828	0.550	0.922	0.952	1.745	0.781
NGRC05582	1.972	0.992	0.745	0.825	0.393	0.762	1.033	1.210	0.869
NGRC05583	1.531	0.850	0.823	0.775	0.335	0.958	0.827	0.875	0.774
NGRC05584	1.794	0.834	1.223	0.825	0.461	0.816	0.792	0.786	0.831
NGRC05585	1.566	0.946	0.855	0.950	0.259	0.615	0.983	0.833	0.813
NGRC05586	0.911	1.072	0.313	0.541	0.333	0.765	0.898	0.438	0.769
NGRC05587	1.089	0.840	0.711	0.764	0.611	1.205	0.821	0.935	0.800
NGRC05588	1.370	1.045	0.548	1.000	0.680	0.711	1.044	0.556	0.799
NGRC05589	1.259	0.660	2.133	0.704	0.672	0.749	0.911	0.386	0.805
NGRC05590	0.711	0.662	0.534	0.697	0.526	1.670	1.088	0.290	0.787
NGRC05591	0.658	0.867	0.634	0.882	0.789	1.086	0.926	0.367	0.833
NGRC05592	0.411	0.707	0.198	0.480	0.175	0.943	0.924	0.169	0.842
NGRC05593	0.431	0.663	0.391	0.619	0.493	1.676	0.978	0.093	0.805

Note: RL: root length; SL: shoot length; R:S: root: shoot ratio; NoR: number of roots; RMC: root moisture content; SMC: shoot moisture content; RWC: relative water content; RV: root volume; NDVI: Normalized Difference Vegetation Index.

Table 5. Correlation among plant growth attributes of 30 maize accessions under different growing conditions: drought condition (above diagonal) and irrigated condition (below diagonal).

	SL	RL	R:S	NoR	RMC	SMC	RWC	RV	NDVI
SL	1	0.44*	0.27	0.33	−0.25	−0.38*	−0.19	0.52***	0.11
RL	−0.11	1	0.76***	0.47**	−0.19	−0.52***	−0.27	0.79***	0.14
R:S	−0.05	0.48**	1	0.52***	−0.19	−0.62***	−0.32	0.8***	0.31
NoR	0.37*	0.38*	0.17	1	−0.26	−0.64***	−0.02	0.59***	0.16
RMC	0.25	−0.38*	0.06	−0.18	1	0.3**	0.29	−0.39*	−0.2
SMC	0.38**	−0.64***	−0.21	−0.15	0.45*	1	0.36	−0.74***	0.00
RWC	0.05	−0.21	0.02	−0.11	0.11	0.16	1	−0.38*	0.06
RV	−0.08	0.94***	0.45*	0.4*	−0.38*	−0.58***	−0.12	1	0.19
NDVI	0.13	0.36	0.27	0.22	−0.13	−0.09	−0.33	0.39*	1

Note: RL: root length; SL: shoot length; R:S: root: shoot ratio; NoR: number of roots; RMC: root moisture content; SMC: shoot moisture content; RWC: relative water content; RV: root volume; NDVI: Normalized Difference Vegetation Index.

*Significant at 5% level. **Significant at 1% level. ***Significant at 0.01% level.

Data availability statement

Data will be made available upon request via the corresponding email address.