Agro-morphological traits-based genetic diversity assessment on oat (Avena sativa L.) genotypes in the central highlands of Ethiopia

Figures & data

Figure 1. Map of the study sites of Holetta (Welmera Woreda) and Ada-Berga (Ada-Berga Woreda) in Ethiopia.

Table 1. List of studied agro-morphological traits and their descriptions.

SN	Trait	Trait code	Unit	Basis of Sampling	Trait description
1	Number of tillers per plant	NTPP	Number	Plant	Number of tillers counted from five randomly selected plants at tillering stage
2	Tillers dry weight	TDW	g	Plant	Tillers dry weight recorded from five randomly selected plants at tillering stage
3	Number of leaves at forage harvest	NLFH	Number	Plant	Leaf number counted from five randomly selected plants at soft dough stage
4	Largest leaf length at forage harvest	LLFH	cm	Plant	Leaf length measured from the base to the tip of the leaf from five plants at soft dough stage
5	Plant height at forage harvest	PHFH	cm	Plant	Plant height measured from ground level to the tip of five plants at soft dough stage
6	Days to forage harvest	DFH	Days	Plot	Number of days counted from 90% emergence to soft dough stage
7	Leaf dry matter yield	LDMY	t/ha	Plot	The yield estimated by multiplying leaf botanical fraction with forage dry matter yield and divided by 100
8	Stem dry matter yield	SDMY	t/ha	Plot	The yield estimated by multiplying stem botanical fraction with forage dry matter yield and divided by 100
9	Panicle dry matter yield	PDMY	t/ha	Plot	The yield estimated by multiplying panicle botanical fraction with forage dry matter yield and divided by 100
10	Forage yield production rate	FYPR	kg/ha/day	Plot	The rate estimated by dividing forage dry matter yield to days to forage harvest
11	Forage dry matter yield	FDMY	t/ha	Plot	The yield estimated at soft dough stage after oven-drying in 105°C for 24 h
12	Plant height at grain harvest	PHGH	cm	Plant	Plant height recorded from ground level to the tip of five plants at grain maturity
13	Panicle length at grain harvest	PLGH	cm	Plant	The length measured from the base to the tip of the panicle from five randomly selected plants at physiological maturity
14	Days to seed harvest	DSH	Days	Plot	Number of days counted from 90% emergence to physiological maturity
15	Grain filling period	GFP	Days	Plot	Number of days between days for heading to days to physiological maturity
16	Number of spikes per panicle	NSPP	Number	Plant	Spikes counted from five randomly selected plants at grain maturity stage
17	Number of spikelets per panicle	NSLPP	Number	Plant	Spikelets counted from five randomly selected plants at grain maturity stage
18	Total biological yield	TBY	t/ha	Plot	Biological yield determined by summing grain yield and straw yield at grain maturity stage
19	Biological yield production rate	BYPR	kg/ha/day	Plot	The rate estimated by dividing biological yield to days to seed harvest
20	Grain sink filling rate	GSFR	kg/ha/day	Plot	The rate estimated by dividing grain yield to the number of days from heading to grain maturity
21	Straw yield	SY	t/ha	Plot	The straw yield estimated by adding aftermath and chaff yields at grain maturity stage
22	Thousand seed weight	TSW	g	Plot	The seed weight estimated at an adjusted moisture content of 12.5%
23	Harvest index	HI	%	Plot	The ratio of grain yield to total above-ground biological yield multiplied by 100
24	Grain yield	GY	t/ha	Plot	The grain yield estimated at an adjusted moisture content of 12.5%

Table 2. Combined analysis of variance (ANOVA) and expected mean squares for the random model of RCBD design.

Sources of variation	Degree of freedom	Mean Square (MS)	Expected Mean Square (EMS)	F-test
Location (L)	L-1	MS1	σ^2e + rσ^2gl + gσ^2r(l) + grσ^2l	MS1/(MS2 + MS4 –MS5)
Replication (R) /Location	L(R-1)	MS2	σ^2e + gσ^2r(l)	MS2/MS5
Genotypes (G)	G-1	MS3	σ^2e + rσ^2gl + rlσ^2g	MS3/MS4
G x L	(G-1)(L-1)	MS4	σ^2e + rσ^2gl	MS4/MS5
Pooled Error	L(G-1)(R-1)	MS5	σ^2e	-

Table 3. Mean squares from a combined ANOVA for 24 traits of 120 oat genotypes grown at Holetta and Ada-Berga in 2020/21 cropping season.

	Mean squares
Traits	Location (L) (DF = 1)	Rep(L) (DF = 4)	Genotype (G) (DF = 119)	G*L (DF = 119)	Error (DF = 476)	CV (%)
Number of tillers per plant (NTPP)	1.15^NS	12.60***	1.20***	0.56*	0.40	25.75
Tillers dry weight (TDW)	25384.00***	72.79***	71.10***	24.26***	7.90	8.57
Number of leaves at forage harvest (NLFH)	105.65**	1.35***	3.08***	0.42*	0.31	11.64
Largest leaf length at forage harvest (LLFH)	4428.78***	32.82^NS	120.40***	61.57***	28.50	13.87
Plant height at forage harvest (PHFH)	1825.96^NS	328.15*	823.48***	171.91**	119.16	8.86
Days to forage harvest (DFH)	28125.00***	15.52*	547.21***	29.06***	5.45	1.82
Leaf dry matter yield (LDMY)	107.65^NS	33.03***	8.94***	3.61*	2.75	23.28
Stem dry matter yield (SDMY)	251.22^NS	92.19***	9.45***	3.51*	2.79	21.33
Panicle dry matter yield (PDMY)	42.24^NS	51.69***	6.49***	2.35^NS	2.00	25.43
Forage yield production rate (FYPR)	3108.36^NS	11765.88***	5116.98***	1548.26^NS	1239.39	21.83
Forage dry matter yield (FDMY)	387.79^NS	194.59***	70.79***	25.21*	19.86	21.72
Plant height at grain harvest (PHGH)	8.67^NS	348.71*	874.79***	167.28***	107.32	8.18
Panicle length at grain harvest (PLGH)	2447.58***	18.32^NS	284.38***	54.44***	10.09	7.85
Days to seed harvest (DSH)	1659.23*	178.86***	687.03***	162.22***	1.68	0.72
Grain filling period (GFP)	150.33^NS	669.97***	475.94***	202.80***	12.56	5.16
Number of spikes per panicle (NSPP)	590.06**	11.43^NS	62.59***	19.55***	12.15	14.53
Number of spikelets per panicle (NSLPP)	12506.67***	117.81^NS	769.14***	259.22***	58.81	16.63
Total biological yield (TBY)	2.58^NS	57.53*	68.32***	38.04***	20.83	19.67
Biological yield production rate (BYPR)	1809.44^NS	1447.56^NS	3252.90***	1411.95***	672.53	19.86
Grain sink filling rate (GSFR)	74113.28**	2143.83*	4366.81***	2041.28***	650.90	23.66
Straw yield (SY)	197.40*	23.79^NS	45.26***	20.69***	12.53	22.18
Thousand seed weight (TSW)	1733.21^NS	321.68***	99.92***	13.84***	7.93	5.81
Harvest index (HI)	5058.85**	205.41***	239.79***	45.81***	26.19	16.33
Grain yield (GY)	246.05*	22.29***	16.05***	5.74***	2.74	22.85

DF = Degree of freedom; CV = Coefficient of variation; NS = Non-significant; *, **, and *** = significantly different at 5, 1, and 0.1%, respectively; Rep (L) = Replication nested under location.

Table 4. Mean performance for 24 traits of 120 oat genotypes grown at Holetta and Ada-Berga in 2020/21 cropping season.

Traits	Location
	Holetta	Ada-Berga	R^2	P-value
Number of tillers per plant (NTPP)	2.4	2.5	0.57	0.7784
Tillers dry weight (TDW) (g)	26.9^b	38.7^a	0.91	<.0001
Number of leaves at forage harvest (NLFH)	5.2^a	4.4^b	0.78	0.0005
Largest leaf length at forage harvest (LLFH) (cm)	41.0^a	36.0^b	0.66	<.0001
Plant height at forage harvest (PHFH) (cm)	121.6	124.8	0.68	0.0768
Days to forage harvest (DFH)	121.8^b	134.3^a	0.97	<.0001
Leaf dry matter yield (LDMY) (t/ha)	6.7	7.5	0.57	0.1457
Stem dry matter yield (SDMY) (t/ha)	7.2	8.4	0.62	0.1744
Panicle dry matter yield (PDMY) (t/ha)	5.8	5.3	0.58	0.4179
Forage yield production rate (FYPR) (kg/ha/day)	163.3	159.2	0.59	0.6373
Forage dry matter yield (FDMY) (t/ha)	19.8	21.3	0.57	0.2326
Plant height at grain harvest (PHGH) (cm)	126.5	126.7	0.71	0.8894
Panicle length at grain harvest (PLGH) (cm)	38.6^b	42.3^a	0.90	<.0001
Days to seed harvest (DSH)	177.8^b	180.8^a	0.99	0.0442
Grain filling period (GFP) (Days)	68.3	69.2	0.93	0.6892
Number of spikes per panicle (NSPP)	24.9^a	23.1^b	0.64	0.0002
Number of spikelets per panicle (NSLPP)	50.3^a	41.9^b	0.83	<.0001
Total biological yield (TBY) (t/ha)	23.3	23.1	0.57	0.8581
Biological yield production rate (BYPR) (kg/ha/day)	132.2	129.0	0.64	0.3872
Grain sink filling rate (GSFR) (kg/ha/day)	118.0^a	97.7^b	0.73	0.0009
Straw yield (SY) (t/ha)	15.4^b	16.5^a	0.58	0.0418
Thousand seed weight (TSW) (g)	50.0	46.9	0.81	0.0806
Harvest index (HI) (%)	34.0^a	28.7^b	0.76	0.0057
Grain yield (GY) (t/ha)	7.8^a	6.7^b	0.69	0.0253

Means followed by different superscript letters with in a row are significantly different at P < 0.05.

Table 5. Mean comparison of the top 5% forage and seed yielder genotypes with the least yielder 5% genotypes, mean of population and mean of released varieties for 24 traits of oat grown at Holetta and Ada-Berga in 2020/21 cropping season.

	High/low forage yielder genotypes				Differences			High/low seed yielder genotypes				Differences
Traits	Top (A)	Bottom (B)	MP (C)	MRV (D)	(A-B)	(A-C)	(A-D)	Top (A)	Bottom (B)	MP (C)	MRV (D)	(A-B)	(A-C)	(A-D)
NTPP	2.6	2.8	2.5	2.3	−0.2	0.1	0.3	2.3	3.0	2.5	2.3	−0.7	−0.2	0.0
TDW	32.2	32.5	32.8	35.2	−0.3	−0.6	−3.0	33.6	28.8	32.8	35.2	4.8	0.8	−1.6
NLFH	4.9	4.3	4.8	4.3	0.6	0.1	0.6	4.1	5.7	4.8	4.3	−1.6	−0.7	−0.2
LLFH	38.8	34.9	38.5	35.1	3.9	0.3	3.7	35.0	39.6	38.5	35.1	−4.6	−3.5	−0.1
PHFH	136.8	111.8	123.2	117.7	25.0	13.6	19.1	113.8	118.1	123.2	117.7	−4.3	−9.4	−3.9
DFH	127.3	127.1	128.0	118.5	0.2	−0.7	8.8	119.6	147.6	128.0	118.5	−28.0	−8.4	1.1
LDMY	9.7	4.9	7.1	7.0	4.8	2.6	2.7	6.6	5.8	7.1	7.0	0.8	−0.5	−0.4
SDMY	10.9	5.5	7.8	7.6	5.4	3.1	3.3	7.4	6.4	7.8	7.6	1.0	−0.4	−0.2
PDMY	7.7	3.5	5.6	5.4	4.2	2.1	2.3	5.3	4.3	5.6	5.4	1.0	−0.3	−0.1
FYPR	222.7	110.3	161.3	168.9	112.4	61.4	53.8	161.5	112.2	161.3	168.9	49.3	0.2	−7.4
FDMY	28.3	13.9	20.5	20.0	14.4	7.8	8.3	19.3	16.5	20.5	20.0	2.8	−1.2	−0.7
PHGH	138.8	115.4	126.6	120.4	23.4	12.2	18.4	114.5	126.6	126.6	120.4	−12.1	−12.1	−5.9
PLGH	43.0	32.5	40.5	40.9	10.5	2.5	2.1	39.1	32.1	40.5	40.9	7.0	−1.4	−1.8
DSH	176.4	186.6	179.3	175.6	−10.2	−2.9	0.8	176.1	198.3	179.3	175.6	−22.2	−3.2	0.5
GFP	66.7	78.4	68.7	79.1	−11.7	−2.0	−12.4	77.6	67.3	68.7	79.1	10.3	8.9	−1.5
NSPP	26.9	23.4	24.0	25.4	3.5	2.9	1.5	24.7	20.9	24.0	25.4	3.8	0.7	−0.7
NSLPP	58.1	36.0	46.1	48.8	22.1	12.0	9.3	41.3	34.3	46.1	48.8	7.0	−4.8	−7.5
TBY	26.6	18.4	23.2	23.2	8.2	3.4	3.4	24.6	17.1	23.2	23.2	7.5	1.4	1.4
BYPR	152.2	100.2	130.6	132.5	52.0	21.6	19.7	140.1	86.2	130.6	132.5	53.9	9.5	7.6
GSFR	112.0	74.3	107.8	112.8	37.7	4.2	−0.8	137.8	48.4	107.8	112.8	89.4	30.0	25.0
SY	19.4	12.6	16.0	14.4	6.8	3.4	5.0	14.2	13.8	16.0	14.4	0.4	−1.8	−0.2
TSW	44.0	53.0	48.4	50.0	−9.0	−4.4	−6.0	51.8	46.6	48.4	50.0	5.2	3.4	1.8
HI	27.4	31.1	31.3	38.7	−3.7	−3.9	−11.3	42.4	18.7	31.3	38.7	23.7	11.1	3.7
GY	7.3	5.8	7.2	8.8	1.5	0.1	−1.5	10.4	3.2	7.2	8.8	7.2	3.2	1.6

Top 5% high forage yielder oat genotypes (1st = S-122; 2nd = T-1926513; 3rd = 1480; 4th = 1677; 5th = Bona-bas; 6th = 1674); and 5% low forage yielder oat genotypes (115th = SRCPX80Ab1751; 116th = 1690; 117th = SRCPX80Ab2582; 118th = SRCPX80Ab2691; 119th = SRCPX80Ab2050; 120th = Coker SR res 80SA 130); Top 5% high seed yielder oat genotypes (1st = SRCPX80Ab2806; 2nd = SRCPX80Ab2267; 3rd = 715; 4th = 1463; 5th = SRCPX80Ab2291; 6th = A-505); and 5% low seed yielder oat genotypes (115th = 1751; 116th = 1426; 117th = SRCPX80Ab2582; 118th = 1752; 119th = 1842; 120th = 1690); MP = Mean of population; MRV = Mean of released varieties; (See Table 1 for description of abbreviated traits).

Table 6. Mean performance of the top 5% forage and seed yielder genotypes for 24 traits of oat grown at Holetta and Ada-Berga in 2020/21 cropping season.

	Top 5% forage yielder genotypes						Top 5% seed yielder genotypes
Traits	1st	2nd	3rd	4th	5th	6th	1st	2nd	3rd	4th	5th	6th
NTPP	2.5	2.4	2.6	2.9	2.5	2.7	2.3	2.0	2.4	2.3	2.5	2.3
TDW	28.7	32.9	34.5	30.1	31.0	35.8	34.1	32.5	32.6	34.7	33.1	34.3
NLFH	4.5	4.6	5.1	5.6	4.7	4.7	3.9	3.7	5.1	4.3	3.6	4.1
LLFH	36.1	41.3	35.9	45.0	33.2	41.5	32.4	36.7	40.2	34.9	33.3	32.3
PHFH	145.5	140.8	124.3	134.6	143.3	132.2	112.0	109.8	123.4	118.3	101.8	117.5
DFH	126.5	127.3	129.7	135.2	119.7	125.2	117.0	118.2	125.0	123.2	116.7	117.7
LDMY	10.0	10.2	9.4	9.5	9.7	9.6	6.1	6.1	8.0	6.8	6.3	6.1
SDMY	11.7	11.2	11.4	10.9	10.1	9.9	7.2	6.8	9.1	7.9	6.6	7.0
PDMY	8.6	8.4	7.4	7.4	7.4	7.1	5.0	4.4	6.6	5.7	4.9	5.0
FYPR	236.9	234.9	218.3	203.8	227.9	214.4	158.2	147.4	190.5	166.3	152.2	154.6
FDMY	30.3	29.7	28.2	27.7	27.3	26.7	18.4	17.3	23.7	20.4	17.8	18.1
PHGH	139.2	144.7	127.0	137.2	147.2	137.2	109.2	109.3	128.2	121.5	105.3	113.2
PLGH	41.1	52.9	35.1	37.1	43.0	48.8	41.2	40.6	43.0	39.8	40.0	30.2
DSH	171.2	170.5	170.8	184.2	171.2	190.2	179.0	178.3	170.5	170.5	179.2	179.2
GFP	66.8	57.8	58.2	60.3	74.3	82.8	87.0	84.2	61.5	62.7	85.0	85.0
NSPP	27.0	29.1	20.4	26.3	30.4	28.1	24.3	25.8	26.0	24.2	24.0	23.6
NSLPP	82.6	57.3	39.9	45.1	50.2	73.2	42.7	36.0	45.3	49.2	40.2	34.5
TBY	29.3	28.0	27.8	23.5	27.7	23.5	24.7	24.4	26.6	26.6	22.7	22.5
BYPR	171.2	164.6	163.1	128.2	161.9	124.0	137.5	136.6	156.3	156.7	127.1	126.3
GSFR	113.1	114.8	134.3	117.7	101.1	90.7	129.0	126.9	171.8	162.9	118.7	117.5
SY	21.8	21.4	20.3	16.6	20.2	16.1	13.5	13.6	16.1	16.5	12.6	12.7
TSW	36.8	46.4	46.8	50.9	39.7	43.5	50.9	51.0	48.8	46.8	51.1	62.3
HI	25.9	23.8	26.2	29.6	27.0	32.1	45.7	43.4	39.4	37.7	44.3	43.9
GY	7.5	6.6	7.5	6.9	7.5	7.5	11.2	10.7	10.5	10.1	10.0	9.9

Top 5% high forage yielder oat genotypes (1^st = S-122; 2^nd = T-1926513; 3rd = 1480; 4^th = 1677; 5^th = Bona-bas; 6^th = 1674); 5% high seed yield producing genotypes (1^st = SRCPX80Ab2806; 2^nd = SRCPX80Ab2267; 3rd = 715; 4^th = 1463; 5th = SRCPX80Ab2291; 6th = A-505); (See Table 1 for description of abbreviated traits).

Table 7. Components of variance and coefficient of variation for 24 traits of 120 oat genotypes grown at Holetta and Ada-Berga in 2020/21 cropping season.

Traits	Variance component						Coefficient of variation
	σ^2l	σ^2r	σ^2g	σ^2gl	σ^2e	σ^2p	GCV	PCV	ECV
Number of tillers per plant (NTPP)	0.000	0.102	0.107	0.053	0.400	0.200	13.06	17.89	25.30
Tillers dry weight (TDW)	70.263	0.541	7.807	5.453	7.900	11.850	8.52	10.50	8.57
Number of leaves at forage harvest (NLFH)	0.289	0.009	0.443	0.037	0.310	0.513	13.87	14.93	11.60
Largest leaf length at forage harvest (LLFH)	12.119	0.036	9.805	11.023	28.500	20.067	8.13	11.64	13.87
Plant height at forage harvest (PHFH)	4.014	1.742	108.595	17.583	119.160	137.247	8.46	9.51	8.86
Days to forage harvest (DFH)	78.016	0.084	86.358	7.870	5.450	91.202	7.26	7.46	1.82
Leaf dry matter yield (LDMY)	0.205	0.252	0.888	0.287	2.750	1.490	13.27	17.19	23.36
Stem dry matter yield (SDMY)	0.440	0.745	0.990	0.240	2.790	1.575	12.76	16.09	21.41
Panicle dry matter yield (PDMY)	0.000	0.414	0.690	0.117	2.000	1.082	14.83	18.57	25.25
Forage yield production rate (FYPR)	0.000	87.721	594.787	102.957	1239.390	852.830	15.12	18.10	21.83
Forage dry matter yield (FDMY)	0.522	1.456	7.597	1.783	19.860	11.798	13.44	16.76	21.74
Plant height at grain harvest (PHGH)	0.000	2.012	117.918	19.987	107.320	145.798	8.58	9.54	8.18
Panicle length at grain harvest (PLGH)	6.625	0.069	38.323	14.783	10.090	47.397	15.29	17.00	7.84
Days to seed harvest (DSH)	3.666	1.477	87.468	53.513	1.680	114.505	5.22	5.97	0.72
Grain filling period (GFP)	0.000	5.478	45.523	63.413	12.560	79.323	9.82	12.96	5.16
Number of spikes per panicle (NSPP)	1.587	0.000	7.173	2.467	12.150	10.432	11.16	13.46	14.52
Number of spikelets per panicle (NSLPP)	33.857	0.492	84.987	66.803	58.810	128.190	20.00	24.56	16.64
Total biological yield (TBY)	0.000	0.306	5.047	5.737	20.830	11.387	9.68	14.54	19.67
Biological yield production rate (BYPR)	0.000	6.459	306.825	246.473	672.530	542.150	13.41	17.83	19.86
Grain sink filling rate (GSFR)	196.053	12.441	387.588	463.460	650.900	727.802	18.26	25.03	23.67
Straw yield (SY)	0.460	0.094	4.095	2.720	12.530	7.543	12.65	17.17	22.12
Thousand seed weight (TSW)	3.905	2.615	14.347	1.970	7.930	16.653	7.83	8.43	5.82
Harvest index (HI)	13.427	1.494	32.330	6.540	26.190	39.965	18.17	20.20	16.35
Grain yield (GY)	0.613	0.163	1.718	1.000	2.740	2.675	18.21	22.72	22.99

σ²l = Location variance; σ²r = Replication variance; σ²g = Genotypic variance; σ²gl = Genotypic by location interaction variance; σ²e = Environmental variance; σ²p = Phenotypic variance; PCV = Phenotypic coefficient of variation; GCV = Genotypic coefficient of variation; ECV = Environmental coefficient of variation.

Table 8. Heritability, genetic advance, and genetic advance as percent of mean for 24 traits of 120 oat genotypes grown at Holetta and Ada-Berga in 2020/21 cropping season.

Traits	h^2b	GA	GAM
Number of tillers per plant (NTPP)	53.3	0.5	18.7
Tillers dry weight (TDW)	65.9	4.0	12.2
Number of leaves at forage harvest (NLFH)	86.4	1.0	19.9
Largest leaf length at forage harvest (LLFH)	48.9	4.5	11.7
Plant height at forage harvest (PHFH)	79.1	14.9	12.1
Days to forage harvest (DFH)	94.7	13.3	10.4
Leaf dry matter yield (LDMY)	59.6	1.4	19.0
Stem dry matter yield (SDMY)	62.9	1.4	18.3
Panicle dry matter yield (PDMY)	63.8	1.2	21.3
Forage yield production rate (FYPR)	69.7	35.0	21.7
Forage dry matter yield (FDMY)	64.4	4.0	19.3
Plant height at grain harvest (PHGH)	80.9	15.6	12.3
Panicle length at grain harvest (PLGH)	80.9	8.9	21.9
Days to seed harvest (DSH)	76.4	13.4	7.5
Grain filling period (GFP)	57.4	9.7	14.1
Number of spikes per panicle (NSPP)	68.8	3.8	16.0
Number of spikelets per panicle (NSLPP)	66.3	13.2	28.7
Total biological yield (TBY)	44.3	3.2	13.9
Biological yield production rate (BYPR)	56.6	25.1	19.2
Grain sink filling rate (GSFR)	53.3	28.2	26.2
Straw yield (SY)	54.3	2.9	18.1
Thousand seed weight (TSW)	86.1	5.4	11.2
Harvest index (HI)	80.9	8.2	26.0
Grain yield (GY)	64.2	1.9	26.1

h²_b = heritability in broad sense; GA = Genetic advance; GAM = Genetic advance as percent of mean.

Data availability statement

The data supporting the findings of this study are in the figshare repository and can be accessed using the link: http://www.doi.org/10.6084/m9.figshare.21828840.