Genetic variability of panicle architecture traits in different rice accessions under the Eastern Terai conditions of Nepal

Figures & data

Table 1. List of rice accessions used for the study with their source and symbols

S. No	Accessions	Source	Symbols
1	IR92521-172-5-1-1	CVT-RLM	G1
2	NR2182-33-3-2-1-1-1	CVT-RLM	G2
3	NR2191-178-1-1-1-1	CVT-RLM	G3
4	SVIN209	CVT-RLM	G4
5	IR106523-25-34-3-2-13-1-2	CVT-RLM	G5
6	IR14D134	CVT-RLM	G6
7	IR15L17315	CVT-RLM	G7
8	SVIN123	CVT-RLM	G8
9	NR2188-13-5-2-5-1	CVT-RLM	G9
10	NR2187-33-1-2-1-1-1	CVT-RLM	G10
11	IR106523-25-34-3-3-B-45-2	SQTL	G11
12	IR106523-25-34-3-2-B-44-3	SQTL	G12
13	Radha-13	NARC	V1
14	SVIN-312	IET-RLM	G13
15	Jeera Masino	NARC	V2
16	SVIN-072	IET-RLM	G14
17	NR2192-16-1-1-1-1	IET-RLM	G15
18	Bas Dhan (Inferior)	NARC	V3
19	Subarna Sub-1	NARC	V4
20	Ranjeet (Superior)	NARC	V5

Note: CVT-RLM: Coordinated Varietal Trail (CVT) on Rainfed Lowland- Medium (RLM); NARC: Nepal Agriculture Research Council; SQTL: Seedling Stage Quantitative Trait Loci; IET-RLM: Inbred Elite Tropical (IET) Rice- Restorer and Maintainer Lines (RLM); G/V: Genotype/Variety

Figure 1. Map illustrating the experimental site of the study.

Table 2. Meteorological parameters throughout the study period

Months	Max Temp. (^0 C)	Min Temp. (^0 C)	Relative humidity (%)	Precipitation (mm)	UV Index
June	3.43	23.46	76.80	5.3	8.30
July	32.48	24.70	69.48	397.7	7.38
August	32.35	24.96	71.54	356.2	7.48
September	32.06	23.96	70.23	269.8	4.60
October	31.41	21.16	60.67	95.2	4.77

Figure 2. Morphological diversity of panicles in studied rice accessions.

Figure 3. Comparing panicle architecture traits in rice accessions, top five and bottom five performers for each trait including ^(a)panicle length, ^(b)panicle angle, ^(c)panicle weight and ^(d)test weight.

Figure 4. Comparing panicle architecture traits in rice accessions, top five and bottom five performers for each trait including ^(e)panicle number, ^(f)grains/panicle, ^(g)chaffs/panicle and ^(h)flagleaf area.

Table 3. Evaluation of major panicle traits of various rice accessions tested under Eastern terai region of Nepal

Accessions	PL	PA	PW	TW	PN	G/P	C/P	FLA
Bas Dhan (Check)	26.00^cdef	33.00^a	3.20^de	21.82^efg	12.40^abcd	108.87^efgh	29.18^bc	36.46^bcd
IR106523-25-34-3-2-13-1-2	28.30^abc	32.66^a	4.43^ab	22.15^def	11.03^bcd	176.36^a	27.20^bed	38.00^bc
IR106523-25-34-3-2-B-44-3	27.00b^cde	36.66^a	3.66^abcde	21.70^efg	11.46^bcd	122.29^def	28.70^bc	32.68^bcd
IR106523-25-34-3-3-B-45-2	26.72^bcde	33.33^a	3.66^abcde	23.85^de	11.50^bcd	126.43^cdef	27.23^bcd	33.04^bcd
IR14D134	27.72^abc	33.33^a	2.76^e	23.87^de	15.00^a	83.733^i	28.06^bcd	31.48^bcd
IR15L17315	25.24^defg	35.00^a	4.06^abcd	33.41^a	11.76^bcd	93.766^hi	19.03^fgh	34.21^bcd
IR92521-172-5-1-1	27.07^bcde	36.66^a	3.53^abcde	21.45^efg	13.06^abc	105.40^fgh	19.66^efgh	35.97^bcd
Jeera Masino	24.94^efg	34.33^a	3.70^abcde	17.58^i	10.13^cd	158.30^ab	16.26^hi	34.40^bcd
NR2182-33-3-2-1-1-1	27.94^abc	38.66^a	3.80^abcd	23.71^de	13.16^ab	119.73^defg	13.00^i	34.78^bcd
NR2187-33-1-2-1-1-1	24.01^fg	40.33^a	3.43^cde	18.30^hi	10.10^d	138.83^cd	32.55^b	22.44^ef
NR2188-13-5-2-5-1	23.68^g	39.33^a	3.23^de	23.03^de	12.033^bcd	115.66^efg	56.70^a	23.02^ef
NR2191-178-1-1-1-1	27.36^bcd	37.00^a	3.43^cde	21.76^efg	12.400^abcd	107.40^fgh	22.30^defgh	30.67^cd
NR2192-16-1-1-1-1	30.02^a	34.16^a	3.33^cde	19.53^fghi	13.366^ab	128.50^cde	19.53^efgh	33.42^bcd
Radha-13	28.36^abc	36.33^a	4.26^abc	22.12^def	11.700^bcd	136.66^cd	24.26^cdefg	46.82^a
Ranjeet (Check)	27.25^bcde	37.66^a	3.46^bcde	20.96^efgh	10.733^bcd	145.76^bc	19.36^fgh	28.74^de
SVIN-072	27.22^bcde	35.00^a	3.86^abcd	26.92^bc	10.666^bcd	99.366^ghi	18.13^ghi	33.53^bcd
SVIN123	28.74^ab	38.00^a	4.50^a	28.91^b	11.466^bcd	118.63^defg	19.23^fgh	38.85^b
SVIN209	25.98^cdef	38.00^a	4.00^abcd	25.15^cd	12.833^abcd	99.636^ghi	24.72^cdef	32.96^bcd
SVIN-312	27.26^bcde	36.00^a	4.03^abcd	29.08^b	10.833^bcd	107.36^fgh	18.83^fgh	31.10^bcd
Swarna Sub-1	23.52^g	39.33^a	3.13de	18.71^ghi	12.166^abcd	106.81^fgh	25.53^cde	18.23^f
Grand mean	26.72	36.24	3.67	23.20	11.89	119.97	24.47	32.54
CV (%)	4.606	19.362	13.524	7.344	12.512	9.185	13.292	12.535
LSD0.05	2.032	11.589	.821	2.814	2.457	18.199	5.373	6.73
F value	5.98***	0.32NS	2.47**	16.09***	1.99*	12.68***	23.56***	6.95***

Note: PL: Panicle length (cm); PA: Panicle angle; PW: Panicle weight; FLA: Flag leaf area (cm²); G/P: Grains per panicle; C/P: Chaffs per panicle; TW: Test weight (g); PN: Panicle number; CV: Coefficient of variation; LSD: Least significant difference; *Significant at 5% level of significance, **Significant at 1% level of significance, ***Significant at 0.1% level of significance, ^NSNon-significant

Table 4. Statistical overview of panicle traits variation among investigated rice accessions

	Panicle length	Panicle angle	Panicle weight	Test weight	Panicle number	Grains/panicle	Chaffs/panicle	Flag leaf area
N	20	20	20	20	20	20	20	20
Min	23.52	32.66	2.766	17.58	1.10	83.730	13.00	18.23
Max	3.02	4.33	4.50	33.41	15.00	176.30	56.70	46.82
Sum	534.4	724.8	73.53	464.0	237.8	2399.0	489.5	650.9
Mean	26.72	36.24	3.676	23.20	11.89	119.97	24.47	32.54
Std. error	.388	.518	.101	0.882	.271	5.0661	2.038	1.388
Variance	3.021	5.378	.204	15.58	1.468	513.32	83.12	38.56
Stand. dev	1.738	2.319	.452	3.947	1.212	22.656	9.117	6.210
Median	27.15	36.50	3.666	22.13	11.73	117.15	23.28	33.23
Skewness	−.38	.035	.096	0.998	.704	.8616	2.397	−0.35
Kurtosis	−.27	−1.10	−.34	1.086	.791	.7405	8.080	1.574
Geom. mean	26.66	36.17	3.650	22.90	11.83	118.06	23.26	31.92

Table 5. Analysis of genetic variability parameters for panicle traits in rice accessions, including genotypic variation (σ²_G), phenotypic variation (σ²_P), environmental variance (σ²_E), environmental coefficient of variation (ECV), genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), broad sense heritability (h²_bs), genetic advance (GA), and genetic advance as percentage of the mean (GAM)

	Panicle length	Panicle angle	Panicle weight	Test weight	Panicle number	Grains/panicle	Chaffs/panicle	Flag leaf area
Grand Mean	26.7213	36.2417	3.6767	23.2049	11.8917	119.9777	24.4765	32.5454
Standard Error of Mean (SEm)	.6661	3.817	.2901	0.9960	.8661	6.3530	1.8489	2.3822
Environmental Variance (σ^2E)	1.3310	43.7081	.2524	2.9761	2.2503	121.0806	1.2555	17.0244
Genotypic Variance (σ^2G)	2.5775	9.1908	.1202	14.5946	.7189	472.9659	79.7099	32.8897
Phenotypic Variance (σ^2P)	3.9085	34.5173	.3726	17.5707	2.9692	594.0465	89.9654	49.9141
Environmental Coefficient of Variance (ECV)	4.3174	18.242	13.6647	7.4344	12.6147	9.1714	13.0837	12.6779
Genotypic Coefficient of Variance (GCV)	6.0082	8.365	9.4297	16.4633	7.13	18.1265	36.4760	17.6214
Phenotypic Coefficient of Variance (PCV)	7.3986	16.211	16.6023	18.0640	14.4903	2.3147	38.7515	21.7081
Heritability (h^2bs)	.6595	.2663	.3226	0.8306	.2421	.7962	.8860	0.6589
Genetic Advance (GA)	2.6857	3.2226	.4056	7.1724	.8594	39.9748	17.3118	9.5899
Genetic Advance as percentage of mean (GAM)	1.0508	8.892	11.0317	30.9089	7.2269	33.3185	7.7282	29.4663

Figure 5. Scree plot of eigen values after principal component analysis (PCA).

Figure 6. Principal component analysis (PCA) of studied rice accessions showing the genotypic relationship in a graphical representation (biplot) on the basis of different panicle traits.

Table 6. Principal component analysis (PCA) of diverse morphological traits in investigated rice accessions

	PC1	PC2	PC3	PC4	PC5	PC6	PC7	PC8
Panicle length	.46407267	−.16588805	−.2704741652	.20628669	−.32947254	.65110760	.3135764	.10287752
Panicle angle	−.32078274	.14958686	.3774593618	.60085541	−.54089113	−.06872363	.1358382	−.23554461
Panicle weight	.42616904	.31010500	.3935757104	−.02623695	−.25857081	−.10988067	−.3514262	.60348294
Test weight	.25593831	−.26030796	.6530705038	−.26332982	.07439111	.30290171	−.1682335	−.49528342
Panicle number	−.02640579	−.63369399	−.2576868667	.09424361	−.35731538	−.16548766	−.6058106	−.01957960
Grains/panicle	.11493743	.61846287	−.3548941220	−.05591781	−.14045161	.16905930	−.4579594	−.46602783
Chaffs/panicle	−.38045538	.03712992	.0004478315	−.70007594	−.55910363	.12720623	.1605623	.09596867
Flag leaf area	.52531548	−.02713954	−.1030178323	−.15579674	−.25786415	−.62877985	.3590285	−.31250975
Standard deviation	1.7001	1.3782	1.1706	.88115	.7798	.51246	.3784	.2228
Proportion of Variance	.3613	.2374	.1713	.09705	.0760	.03283	.0179	.0062
Cumulative Proportion	.3613	.5987	.7700	.86707	.9431	.97590	.9938	1.0000

Figure 7. Relationship of different panicle traits in studied rice accessions by multiple correlation analysis [*Significant at 5% level of significance, **Significant at 1% level of significance, ***Significant at 0.1% level of significance, ^▪Significant at 10% level of significance].

Figure 8. Dendrogram illustrating the similarity index among various rice accessions based on diverse panicle traits.

Data availability statement

Data included in article/supplement material/referenced in the article. https://drive.google.com/file/d/1A2e12TV6JedCicfl2dcHL4XkeNnuh376/view?usp=sharing