Linseed is a multipurpose crop and the crop needs further improvement to increase production and yield due to its high value and demand. This study aimed to assess the extent and pattern of genetic variability of forty linseed genotypes based on diverse agro–morphological and yield attributes. The field experiment was conducted following a Randomized Complete Block Design with three replications. Linseed germplasm showed a wide range of phenotypic expression, genetic variability and heritability for 30 studied traits. A low to high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed. The lowest genotypic (σ2g) and phenotypic variances (σ2p) were found in capsule diameter (CD), length of calyx (LC), capsule length (CL), seed length (SL), and seed breadth (SB). High broad-sense heritability (h2b) with high genetic advance as a percentage of mean (GAM) were observed in days to germination started (DGS), days to 80% emergence (DE), plant height at 28 and 40 DAS, number of flowers (NFPP), filled capsules (NFCPP) and yield per plant (YPP) indicating additive gene action exists for these characters. Hierarchical cluster analysis separated 40 genotypes into five clusters, where Clusters I to V assembled with 13, 4, 4, 5 and 14 genotypes, respectively. Considering yield and yield attributes, Cluster-IV (G3, G4, G6, G10 and G31) genotypes showed promising while, Cluster-II (G2, G16, G35, G36) and Cluster-III (G1, G33, G39 and G40) genotypes were dominant on plant morphological traits. Based on principal component analysis (PCA), few characters such as YPP, NFPP, NFCPP, days to first flowering and capsule formation, early emergence, days to branch initiation and plant heights at different growth stages revealed important and effective traits for consideration in the selection of linseed breeding programs.
Linseed (
Linseed is grown in 3.26 million hectares worldwide, with a yield of about 3.18 million tons and productivity of 1011 kilograms per hectare [
The study of genetic variability allows for better selection and aids in the development of high-yielding varieties. The magnitude of heritable variation in the traits studied is extremely important for selecting the genotype for any breeding program. Specific genotypes in a population’s propensity to differ from one another are measured by genetic variability. Genetic heterogeneity in a population is crucial for biodiversity because, without it, a population’s ability to adapt to environmental changes is hampered and thus makes it more prone to extinction. Genetic variation and the mode of inheritance of quantitative and qualitative traits are crucial in the planning of a breeding program [
Plant breeders may use the diversity of plant genetic resources to create new and improved cultivars with desirable traits, including farmer-preferred traits (high yield capacity, broad seed, etc.) as well as breeder-preferred traits (pest and disease tolerance, photosensitivity, etc.) [
A total of 40 diverse linseed genotypes was used in this study for characterization. Among them, 26 genotypes were collected from Plant Genetic Resources Centre (PGRC), Bangladesh Agricultural Research Institute (BARI), 11 genotypes from various agro-ecological areas in Bangladesh, and the remaining three from abroad (China, Vietnam and Canada). The detailed information of these genotypes is presented in
Codes | Genotypes name | Sources | Codes | Genotypes name | Sources |
---|---|---|---|---|---|
G1 | Bandarban | Local | G21 | BD-7141 | PGRC, BARI |
G2 | BARI Tishi-1 (Neela) | ORC, BARI | G22 | BD-7142 | PGRC, BARI |
G3 | Barishal | Local | G23 | BD-7143 | PGRC, BARI |
G4 | BD-10696 | PGRC, BARI | G24 | BD-7144 | PGRC, BARI |
G5 | BD-10697 | PGRC, BARI | G25 | BD-7145 | PGRC, BARI |
G6 | BD-10698 | PGRC, BARI | G26 | BD-7146 | PGRC, BARI |
G7 | BD-10699 | PGRC, BARI | G27 | BD-7147 | PGRC, BARI |
G8 | BD-10700 | PGRC, BARI | G28 | BD-9944 | PGRC, BARI |
G9 | BD-10701 | PGRC, BARI | G29 | Chilmari (Black) | Local |
G10 | BD-10702 | PGRC, BARI | G30 | Chilmari (Light) | Local |
G11 | BD-10703 | PGRC, BARI | G31 | China | China |
G12 | BD-10704 | PGRC, BARI | G32 | Faridpur | Local |
G13 | BD-10705 | PGRC, BARI | G33 | Hatibanda | Local |
G14 | BD-10706 | PGRC, BARI | G34 | Hobigonj | Local |
G15 | BD-10707 | PGRC, BARI | G35 | Lin 1903 | Local |
G16 | BD-10708 | PGRC, BARI | G36 | Sirajgonj | Local |
G17 | BD-10709 | PGRC, BARI | G37 | Tangail | Local |
G18 | BD-10710 | PGRC, BARI | G38 | Ulipur | Local |
G19 | BD-10711 | PGRC, BARI | G39 | Vietnam | Vietnam |
G20 | BD-7140 | PGRC, BARI | G40 | Canada | Canada |
Note: BARI: Bangladesh Agricultural Research Institute; ORC: Oilseed Research Centre; PGRC: Plant Genetic Resources Centre.
During the 2018–2019 cropping season, the 40 genotypes were planted in the field for evaluating the morphological and plant architecture traits. The experiment was set following Randomized Complete Block Design (RCBD) with three replications. Each replication consists of two rows of each genotype. With continuous line sowing, the unit plot was 3.0 m × 0.6 m (two lines). The plant-to-plant spacing within a row was maintained at 5–7 cm (DAS). To ensure adequate germination, pre-sowing irrigation was used. Before sowing, the experimental plots were well prepared, and Farm Yard Manure (FYM) was added. Linseed cultivation was carried out using the prescribed fertilizer and manure doses [
The agro–morphological traits, yield attributes and yield data were recorded on five randomly selected plants from each plot. The following data were recorded.
The number of days from sowing to seed germination, 80% emergence and branch initiation were counted based on the sowing date.
At 28, 40, 60 and 82 d after sowing (DAS), the height of each selected plant was measured in centimeters from the surface of the soil to the top of the plant and average values were calculated.
The number of leaves plant–1 (NLPP) was counted at 30 DAS and the number of branches produced by each plant was recorded at 40 DAS.
The base diameter was measured at 2 cm above the soil surface and main branch diameter was measured at 6 cm above the soil surface at 42 DAS.
The number of days from sowing to top branch initiation and first flowering was counted based on the sowing date. The height of the main stem was measured in centimeters in selected plants at 82 DAS.
The length of flower with its different whorls was measured in millimeters and average values were used for statistical analysis.
The number of days to flower stops and capsule formation were counted on the basis of sowing date.
The counting of number of flowers, filled and unfilled capsules per selected plants were done at 115 DAS.
The length and diameter of capsules were measured in millimeter at 115 DAS.
After harvesting, the selected plants were manually threshed in the threshing floor and cleaned properly. Then the seed length (SL) and seed breadth (SB) of each seed were measured in millimeter. The number of seeds of each capsule (NSPC) was counted and replication wise mixed in a lot. Then 1000 seeds were randomly selected from each lot and weighed (TSW) in grams on sensitive electric balance in the laboratory. Finally, seed yield plant–1 (YPP) was determined in grams.
The results for different agro–morphological characteristics were analyzed using the Statistix 10 software package, and the means were separated using Duncan’s multiple range test (DMRT) at a 5% level of significance. The genotypic variance (σ2g) and phenotypic variance (σ2p) were calculated as:
Variances below zero were adjusted to zero according to Robinson et al. [
Heritability was categorized as low (0–0.30), moderate (0.30–0.60) and high (>0.60) [
where σ2g = genotypic variance, σ2p = phenotypic variance,
Genetic advance (GA) and Genetic advance as a per cent of mean (GAM) were computed by the following formula [
where, k = selection differential at 5% selection intensity; σp = phenotypic standard deviation; h2b = broad-sense heritability.
Genetic advance as a per cent of mean was categorized as low (<10%), moderate (10%–20%) and high (>20%) [
The multivariate analysis was performed using R (
The 30 measured traits showed significant variations among genotypes except for NB40, BD42, MBD42, NB60, NUFCPP, CD, CL, SB and NSPC (
Genotype | DGS | DE | DBI | PH28 | NLPP | NB40 | PH40 | BD42 | MBD42 | DFF | PH60 | NBPP60 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
G1 | 6.0 | 8.3 | 28.0 | 12.3 | 96.3 | 5.6 | 23.7 | 3.7 | 2.79 | 54.3 | 47.3 | 12.4 |
G2 | 4.3 | 6.0 | 25.0 | 24.3 | 139.3 | 5.2 | 49.3 | 5.7 | 4.26 | 38.3 | 72.3 | 8.2 |
G3 | 5.0 | 6.7 | 25.0 | 14.7 | 112.3 | 5.5 | 28.8 | 5.6 | 4.75 | 48.7 | 58.7 | 8.1 |
G4 | 4.3 | 6.0 | 25.0 | 14.0 | 116.7 | 5.9 | 26.3 | 4.5 | 5.15 | 49.7 | 50.0 | 12.6 |
G5 | 4.3 | 6.0 | 25.0 | 13.7 | 96.0 | 7.1 | 26.4 | 5.21 | 3.66 | 50.3 | 44.3 | 12.4 |
G6 | 5.0 | 6.0 | 25.0 | 14.7 | 111.3 | 5.2 | 25.9 | 5.51 | 3.87 | 49.3 | 48.0 | 11.4 |
G7 | 4.3 | 6.0 | 25.0 | 15.7 | 129.7 | 6.9 | 28.0 | 5.7 | 3.55 | 49.0 | 50.3 | 12.8 |
G8 | 5.0 | 6.0 | 25.0 | 14.7 | 136.3 | 6.9 | 27.1 | 5.7 | 3.58 | 48.7 | 53.7 | 11.8 |
G9 | 5.0 | 6.0 | 25.0 | 14.3 | 108.0 | 6.5 | 25.9 | 5.1 | 3.67 | 54.3 | 44.3 | 12.1 |
G10 | 6.7 | 6.0 | 24.7 | 14.0 | 109.7 | 6.3 | 27.3 | 4.9 | 3.40 | 47.7 | 52.0 | 10.7 |
G11 | 5.0 | 6.0 | 25.0 | 15.0 | 122.0 | 6.7 | 27.9 | 4.5 | 3.65 | 49.0 | 45.0 | 14.3 |
G12 | 5.0 | 6.0 | 25.0 | 12.3 | 95.7 | 5.4 | 21.9 | 4.5 | 3.49 | 49.3 | 43.3 | 12.3 |
G13 | 5.0 | 6.0 | 25.0 | 14.0 | 93.7 | 5.7 | 26.8 | 4.5 | 3.81 | 43.0 | 51.0 | 8.3 |
G14 | 5.0 | 6.0 | 25.0 | 15.0 | 123.0 | 6.1 | 29.9 | 5.6 | 3.85 | 41.0 | 50.7 | 10.3 |
G15 | 5.0 | 6.0 | 25.0 | 14.0 | 103.0 | 5.3 | 26.5 | 4.6 | 3.44 | 48.3 | 48.3 | 13.0 |
G16 | 5.0 | 6.0 | 25.0 | 15.7 | 100.3 | 5.6 | 31.7 | 6.2 | 4.32 | 40.3 | 55.0 | 6.7 |
G17 | 5.0 | 6.0 | 25.0 | 17.0 | 105.0 | 5.5 | 32.4 | 5.4 | 4.07 | 39.0 | 54.0 | 10.7 |
G18 | 5.0 | 6.0 | 25.0 | 13.7 | 86.0 | 5.3 | 27.1 | 4.4 | 3.53 | 50.7 | 49.0 | 11.3 |
G19 | 5.0 | 6.0 | 25.0 | 15.0 | 116.7 | 6.5 | 28.2 | 5.1 | 3.81 | 46.0 | 52.7 | 8.7 |
G20 | 5.0 | 6.0 | 25.0 | 16.0 | 101.3 | 5.7 | 28.4 | 5.2 | 3.74 | 45.0 | 52.7 | 8.7 |
G21 | 5.0 | 6.0 | 25.0 | 14.7 | 106.0 | 4.8 | 26.8 | 4.8 | 3.83 | 46.7 | 47.7 | 10.7 |
G22 | 5.0 | 6.0 | 25.0 | 17.3 | 133.0 | 6.0 | 32.1 | 4.9 | 3.57 | 40.7 | 55.7 | 9.0 |
G23 | 5.0 | 6.0 | 26.3 | 15.3 | 80.3 | 5.3 | 25.2 | 4.4 | 3.49 | 43.0 | 48.7 | 9.0 |
G24 | 5.0 | 6.0 | 26.0 | 15.7 | 122.0 | 5.8 | 29.9 | 4.7 | 3.87 | 42.3 | 50.0 | 10.0 |
G25 | 5.0 | 6.0 | 25.0 | 15.0 | 92.3 | 6.0 | 29.4 | 4.7 | 3.62 | 40.7 | 53.3 | 10.0 |
G26 | 5.0 | 6.0 | 25.0 | 16.7 | 107.7 | 5.9 | 27.5 | 5.5 | 3.99 | 42.0 | 50.3 | 9.7 |
G27 | 5.0 | 6.0 | 25.0 | 15.3 | 99.7 | 6.2 | 28.0 | 4.9 | 3.62 | 41.7 | 45.7 | 10.6 |
G28 | 5.7 | 6.0 | 25.0 | 14.3 | 95.3 | 5.7 | 26.7 | 5.0 | 3.77 | 57.3 | 43.0 | 11.0 |
G29 | 5.0 | 6.7 | 26.0 | 13.0 | 111.7 | 5.6 | 23.8 | 4.7 | 3.63 | 48.3 | 39.7 | 11.7 |
G30 | 5.0 | 6.0 | 25.0 | 14.3 | 99.3 | 7.4 | 25.2 | 4.9 | 3.50 | 45.7 | 38.3 | 11.3 |
G31 | 5.0 | 6.0 | 26.3 | 14.7 | 84.0 | 4.9 | 23.44 | 4.9 | 3.97 | 50.3 | 50.0 | 9.3 |
G32 | 5.0 | 6.0 | 25.0 | 19.0 | 97.7 | 5.4 | 37.44 | 4.7 | 3.67 | 39.7 | 54.3 | 9.3 |
G33 | 7.0 | 7.3 | 28.0 | 13.0 | 101.3 | 6.9 | 24.1 | 4.1 | 3.11 | 58.3 | 38.3 | 12.7 |
G34 | 5.0 | 6.0 | 26.0 | 16.3 | 103.3 | 5.6 | 33.9 | 4.8 | 3.70 | 40.7 | 52.3 | 9.2 |
G35 | 5.0 | 6.0 | 25.0 | 19.7 | 103.3 | 6.3 | 37.6 | 5.9 | 4.15 | 42.0 | 67.3 | 8.0 |
G36 | 4.7 | 6.0 | 25.0 | 22.7 | 103.3 | 4.7 | 49.7 | 6.2 | 4.68 | 38.7 | 80.7 | 5.9 |
G37 | 5.0 | 6.0 | 26.0 | 16.7 | 103.3 | 5.8 | 29.7 | 5.3 | 3.93 | 45.7 | 45.7 | 9.9 |
G38 | 5.0 | 6.0 | 27.0 | 15.0 | 91.00 | 6.5 | 24.0 | 4.6 | 3.74 | 50.0 | 44.7 | 12.8 |
G39 | 7.7 | 9.0 | 28.3 | 12.3 | 60.7 | 4.99 | 27.2 | 4.7 | 4.02 | 51.7 | 45.3 | 9.0 |
G40 | 7.0 | 9.0 | 28.7 | 14.3 | 71.3 | 5.3 | 28.1 | 4.7 | 3.31 | 56.3 | 53.7 | 8.8 |
Mean | 5.18 | 6.28 | 25.5 | 15.3 | 104.2 | 5.89 | 28.76 | 4.98 | 3.78 | 46.7 | 50.4 | 10.4 |
SEM | 0.42 | 0.45 | 0.60 | 1.34 | 9.4 | 0.37 | 3.1 | 0.31 | 0.24 | 3.07 | 4.24 | 1.05 |
Genotype | DTBI | LP | LF | LC | PH82 | DCF | HMS82 | DFS | CD | CL | SL | SB |
---|---|---|---|---|---|---|---|---|---|---|---|---|
G1 | 45.0 | 2.9 | 1.90 | 0.60 | 67.7 | 59.7 | 33.0 | 105.3 | 6.38 | 6.30 | 4.02 | 2.00 |
G2 | 30.3 | 3.3 | 1.90 | 0.50 | 89.3 | 43.7 | 39.9 | 78.0 | 6.38 | 5.84 | 4.59 | 2.28 |
G3 | 40.0 | 2.7 | 1.53 | 0.53 | 66.3 | 52.7 | 34.0 | 90.0 | 6.40 | 6.17 | 4.17 | 1.82 |
G4 | 41.7 | 2.9 | 1.37 | 0.53 | 66.3 | 52.0 | 37.7 | 102.3 | 6.14 | 6.33 | 3.96 | 2.14 |
G5 | 43.3 | 3.2 | 1.40 | 0.43 | 65.7 | 52.3 | 34.5 | 96.7 | 6.44 | 6.35 | 4.16 | 2.20 |
G6 | 39.3 | 3.4 | 1.30 | 0.50 | 64.0 | 53.3 | 40.0 | 102.0 | 6.55 | 6.27 | 4.05 | 2.15 |
G7 | 41.7 | 3.3 | 1.40 | 0.50 | 71.7 | 53.3 | 37.7 | 103.3 | 6.37 | 5.99 | 3.95 | 2.00 |
G8 | 40.0 | 3.2 | 1.40 | 0.50 | 77.7 | 51.7 | 38.3 | 104.0 | 6.20 | 6.35 | 3.93 | 1.95 |
G9 | 46.0 | 3.5 | 1.60 | 0.50 | 68.3 | 58.7 | 37.1 | 105.0 | 6.78 | 6.21 | 3.99 | 2.02 |
G10 | 41.7 | 3.6 | 2.13 | 0.50 | 69.3 | 53.0 | 37.4 | 101.7 | 6.47 | 6.28 | 4.21 | 1.90 |
G11 | 41.3 | 3.7 | 1.53 | 0.50 | 67.3 | 53.3 | 35.2 | 107.3 | 6.27 | 6.15 | 3.65 | 1.63 |
G12 | 42.0 | 3.5 | 1.40 | 0.50 | 67.7 | 54.0 | 32.4 | 100.7 | 6.43 | 6.60 | 3.98 | 2.00 |
G13 | 38.7 | 3.5 | 1.43 | 0.50 | 61.7 | 47.0 | 37.5 | 99.0 | 6.59 | 6.42 | 4.08 | 2.17 |
G14 | 36.7 | 3.3 | 1.40 | 0.53 | 58.7 | 45.3 | 35.9 | 92.7 | 6.56 | 6.33 | 4.21 | 1.97 |
G15 | 38.7 | 3.4 | 1.27 | 0.50 | 71.3 | 52.7 | 38.2 | 107.0 | 6.02 | 6.42 | 3.81 | 2.03 |
G16 | 35.7 | 3.8 | 1.47 | 0.57 | 74.0 | 45.0 | 41.7 | 96.0 | 6.51 | 6.26 | 4.15 | 2.31 |
G17 | 32.3 | 3.6 | 1.33 | 0.50 | 72.3 | 44.3 | 41.6 | 100.0 | 6.28 | 5.97 | 4.32 | 2.08 |
G18 | 40.0 | 3.2 | 1.37 | 0.50 | 74.3 | 53.7 | 39.4 | 106.0 | 6.30 | 6.23 | 4.01 | 2.15 |
G19 | 41.3 | 3.3 | 1.30 | 0.53 | 70.3 | 48.7 | 40.8 | 101.0 | 6.22 | 5.70 | 4.08 | 1.85 |
G20 | 39.7 | 3.7 | 1.43 | 0.50 | 75.3 | 49.0 | 40.2 | 103.0 | 6.40 | 6.14 | 4.05 | 2.09 |
G21 | 39.7 | 3.6 | 1.53 | 0.50 | 80.3 | 49.0 | 38.9 | 101.7 | 6.37 | 5.93 | 4.24 | 2.19 |
G22 | 35.0 | 3.6 | 1.57 | 0.50 | 73.7 | 45.7 | 38.4 | 98.0 | 6.76 | 6.51 | 4.43 | 2.15 |
G23 | 37.7 | 3.5 | 1.40 | 0.43 | 72.3 | 47.3 | 36.6 | 102.0 | 6.53 | 6.40 | 4.17 | 2.23 |
G24 | 39.3 | 3.7 | 1.47 | 0.50 | 69.0 | 46.0 | 36.2 | 103.7 | 6.46 | 6.16 | 4.38 | 2.15 |
G25 | 36.0 | 3.4 | 1.40 | 0.50 | 70.0 | 45.3 | 38.1 | 100.0 | 6.44 | 6.38 | 3.93 | 2.14 |
G26 | 36.3 | 3.6 | 1.53 | 0.50 | 65.3 | 46.3 | 38.9 | 98.7 | 6.42 | 6.39 | 4.00 | 2.06 |
G27 | 36.0 | 3.3 | 1.37 | 0.50 | 68.7 | 45.7 | 34.9 | 100.3 | 5.90 | 5.69 | 4.18 | 2.21 |
G28 | 42.7 | 3.5 | 1.53 | 0.50 | 73.0 | 59.3 | 36.9 | 105.3 | 6.57 | 6.42 | 4.13 | 2.09 |
G29 | 41.0 | 3.7 | 1.60 | 0.50 | 64.7 | 53.0 | 32.2 | 108.0 | 6.25 | 6.02 | 4.12 | 2.19 |
G30 | 39.3 | 3.6 | 1.53 | 0.50 | 66.3 | 49.7 | 27.4 | 104.7 | 6.40 | 5.77 | 4.11 | 2.11 |
G31 | 41.0 | 3.4 | 1.47 | 0.50 | 66.0 | 55.7 | 40.2 | 104.0 | 6.29 | 6.41 | 3.85 | 2.07 |
G32 | 34.7 | 3.1 | 1.50 | 0.47 | 85.3 | 44.7 | 43.0 | 103.0 | 6.23 | 5.94 | 4.30 | 2.22 |
G33 | 41.0 | 3.0 | 1.43 | 0.47 | 68.7 | 64.0 | 30.6 | 107.7 | 6.36 | 6.10 | 3.50 | 2.01 |
G34 | 36.3 | 3.4 | 1.43 | 0.50 | 76.3 | 45.7 | 36.8 | 89.3 | 6.25 | 6.45 | 4.25 | 2.16 |
G35 | 32.3 | 3.9 | 1.60 | 0.53 | 91.3 | 47.7 | 38.1 | 103.7 | 6.54 | 6.73 | 4.77 | 2.40 |
G36 | 30.3 | 3.6 | 1.50 | 0.57 | 100.7 | 43.3 | 56.5 | 100.0 | 6.53 | 6.41 | 3.89 | 2.33 |
G37 | 38.3 | 3.6 | 1.53 | 0.50 | 82.3 | 51.0 | 39.9 | 101.3 | 6.08 | 5.99 | 4.09 | 2.20 |
G38 | 40.3 | 3.4 | 1.47 | 0.50 | 69.3 | 52.7 | 34.6 | 104.3 | 6.22 | 6.20 | 4.12 | 2.05 |
G39 | 39.0 | 3.4 | 1.47 | 0.50 | 73.0 | 56.0 | 34.0 | 102.7 | 6.64 | 6.25 | 4.18 | 2.35 |
G40 | 41.3 | 3.5 | 1.50 | 0.50 | 86.3 | 55.7 | 54.1 | 104.3 | 6.38 | 5.89 | 4.18 | 2.05 |
Mean | 38.9 | 3.43 | 1.49 | 0.51 | 72.4 | 50.7 | 37.8 | 101.1 | 6.38 | 6. 22 | 4.11 | 2.11 |
SEM | 2.0 | 0.15 | 0.09 | 0.02 | 4.62 | 2.86 | 2.73 | 3.30 | 0.10 | 0.14 | 0.13 | 0.09 |
Note: DGS Days to germination started; DE Days to 80% emergence; DBI Days to branch initiation; PH28 Plant height at 28 DAS (cm); NLPP Number of leaves plant–1 at 30 DAS; NB40 Number of branches at 40 DAS; PH40 Plant height at 40 DAS (cm); BD42 Base diameter at 42 DAS (mm); MBD42 Main branch diameter at 42 DAS (mm); DFF Days to first flowering; PH60 Plant height at 60 DAS (cm); NBPP60 Number of branches plant–1 at 60 DAS; DTBI Days to top branch initiation; LP Length of pedicel (mm); LF Length of flower (mm); LC Length of calyx (mm); PH82 Plant height at 82 DAS (cm); DCF Days to capsule formation; HMS82 Height of main stem at 82 DAS (cm); DFS Days to flowering stops; CD Capsule diameter at 115 DAS (mm); CL Capsule length at 115 DAS (mm); SL Seed length (mm); SB Seed breadth (mm).
The genotypes varied significantly in relation to yield and yield attributing characters (
In the present study, high magnitude of phenotypic variance (σ2p) and genotypic variance (σ2g) were recorded in NFPP, NFCPP, NLPP and low magnitude in most of the traits like DGS, DE, DBI, BD42, MBD42, LP, LF, LC, CD, CL, SL, SB, NSPC and TSW (
Heritability is a strong indicator of character transfer from parents to offspring. Estimation of heritability of broad-sense (h2b) in the present study indicated that most of the studied traits were low (<30%) to moderately (30%–60%) heritable and a few traits were highly heritable (
Traits | Grand mean | σ2g | σ2p | GCV (%) | PCV (%) | h2b (%) | GA | GAM | CV% |
---|---|---|---|---|---|---|---|---|---|
DGS | 5.18 | 0.49 | 0.66 | 13.5 | 15.70 | 74.8 | 1.23 | 23.89 | 8.02 |
DE | 6.28 | 0.53 | 0.72 | 11.6 | 13.5 | 74.0 | 1.26 | 20.6 | 6.88 |
DBI | 25.5 | 0.89 | 1.51 | 3.69 | 4.82 | 58.7 | 1.49 | 5.83 | 3.09 |
PH28 | 15.33 | 4.46 | 7.12 | 13.78 | 17.40 | 62.7 | 3.45 | 22.47 | 10.63 |
NLPP | 104.24 | 104.03 | 591.10 | 9.78 | 23.32 | 17.6 | 8.81 | 8.45 | 21.17 |
NB40 | 5.89 | 0.14 | 1.01 | 6.27 | 16.99 | 13.61 | 0.28 | 4.76 | 15.79 |
PH40 | 28.76 | 24.34 | 35.79 | 17.16 | 20.80 | 68.0 | 8.38 | 29.14 | 11.77 |
BD42 | 4.98 | 0.09 | 0.70 | 6.09 | 16.83 | 13.1 | 0.23 | 4.55 | 15.68 |
MBD42 | 3.78 | 0.12 | 0.73 | 7.06 | 21.78 | 12.51 | 0.21 | 5.62 | 23.12 |
DFF | 46.65 | 24.06 | 36.75 | 10.51 | 12.99 | 65.4 | 8.17 | 17.53 | 7.63 |
PH60 | 50.43 | 41.74 | 78.63 | 12.81 | 17.58 | 53.08 | 9.69 | 19.23 | 12.04 |
NB60 | 10.42 | 1.03 | 8.02 | 9.73 | 27.18 | 12.81 | 0.75 | 7.17 | 25.38 |
DTBI | 38.88 | 9.46 | 7.9 | 7.9 | 10.71 | 54.5 | 4.68 | 12.02 | 7.9 |
LP | 3.43 | 0.03 | 0.13 | 4.95 | 10.60 | 21.8 | 0.16 | 4.75 | 9.38 |
LF | 1.49 | 0.02 | 0.04 | 9.63 | 13.6 | 50.12 | 0.209 | 14.05 | 9.60 |
LC | 0.5 | 0.001 | 0.001 | 4.43 | 7.42 | 35.71 | 0.028 | 5.45 | 5.95 |
PH82 | 72.36 | 51.2 | 89.8 | 9.89 | 13.09 | 57.03 | 11.13 | 15.38 | 8.58 |
DCF | 50.73 | 19.32 | 34.96 | 8.67 | 11.66 | 55.28 | 6.73 | 13.27 | 7.79 |
HMS82 | 37.84 | 16.14 | 34.85 | 10.62 | 15.6 | 46.32 | 5.63 | 14.89 | 11.43 |
DFS | 101.13 | 25.38 | 46.64 | 4.98 | 6.75 | 54.43 | 7.65 | 7.57 | 4.56 |
NFPP | 303.6 | 1537.83 | 2108.3 | 12.92 | 15.13 | 72.9 | 6.89 | 22.72 | 7.87 |
NFCPP | 253.1 | 1241.7 | 1599.2 | 13.92 | 15.8 | 77.6 | 6.39 | 25.27 | 7.47 |
NUFCPP | 50.66 | 1.7 | 100.9 | 2.58 | 19.83 | 1.69 | 0.35 | 0.69 | 19.66 |
CD | 6.38 | 0.001 | 0.09 | 0.27 | 4.79 | 0.32 | 0.001 | 0.031 | 4.78 |
CL | 6.21 | 0.02 | 0.08 | 3.51 | 7.78 | 13.07 | 0.13 | 2.09 | 8.28 |
SL | 4.1 | 0.026 | 0.10 | 3.9 | 7.74 | 25.35 | 0.17 | 4.03 | 6.69 |
SB | 2.1 | 0.01 | 0.06 | 3.05 | 11.54 | 6.97 | 0.035 | 1.66 | 11.13 |
NSPC | 8.9 | 0.053 | 0.78 | 2.6 | 9..9 | 6.8 | 0.12 | 1.4 | 9.59 |
TSW | 4.39 | 0.053 | 0.26 | 5.29 | 11.64 | 20.68 | 0.22 | 4.96 | 10.37 |
YPP | 9.91 | 3.1 | 4.95 | 17.78 | 22.45 | 62.8 | 2.88 | 29.01 | 13.7 |
Note: DGS Days to germination started; DE Days to 80% emergence; DBI Days to branch initiation; PH28 Plant height at 28 DAS (cm); NLPP Number of leaves plant–1 at 30 DAS; NB40 Number of branches at 40 DAS; PH40 Plant height at 40 DAS (cm); BD42 Base diameter at 42 DAS (mm); MBD42 Main branch diameter at 42 DAS (mm); DFF Days to first flowering; PH60 Plant height at 60 DAS (cm); NBPP60 Number of branches plant–1 at 60 DAS; DTBI Days to top branch initiation; LP Length of pedicel (mm); LF Length of flower (mm); LC Length of calyx (mm); PH82 Plant height at 82 DAS (cm); DCF Days to capsule formation; HMS82 Height of main stem at 82 DAS (cm); DFS Days to flowering stops; NFPP Number of flowers plant–1; NFCPP Number of filled capsules plant–1; NUFCPP Number of unfilled capsules plant–1; CD Capsule diameter at 115 DAS (mm); CL Capsule length at 115 DAS (mm); SL Seed length (mm); SB Seed breadth (mm); NSPC Number of seeds capsule–1; TSW 1000-seed weight (g); YPP Yield plant–1 (g).
The result of cluster analysis for yield and yield contributing morphological traits and their relative contribution towards the total genetic divergence is shown in
The mean values of measured traits for each cluster are summarized in
Traits | Cluster-I | Cluster-II | Cluster-III | Cluster-IV | Cluster-V |
---|---|---|---|---|---|
DGS | 5.00b | 4.75b | 7.00a | 5.20b | 4.95b |
DE | 6.00b | 6.00b | 8.42a | 6.13b | 6.05b |
DBI | 25.26b | 25.00b | 28.25a | 25.20b | 25.29b |
PH28 | 15.95b | 20.00a | 13.00c | 14.40c | 14.43c |
NLPP | 105.00a | 111.50a | 82.42a | 106.80a | 106.79a |
NB40 | 5.72b | 5.55b | 5.69b | 5.58b | 6.31a |
PH40 | 29.84b | 40.39a | 25.78c | 26.35c | 26.15c |
BD42 | 4.93b | 5.95a | 4.27b | 5.09ab | 4.93b |
MBD42 | 3.76a | 4.29a | 3.31a | 4.23a | 3.63a |
DFF | 41.95c | 40.25c | 55.17a | 49.13b | 49.55b |
PH60 | 51.26b | 66.25a | 46.17bc | 51.73b | 45.88c |
NB60 | 9.65bc | 7.44c | 10.72ab | 10.42ab | 11.90a |
DTBI | 36.79b | 32.75c | 41.58a | 40.73a | 41.14a |
LP | 3.49ab | 3.65a | 3.20b | 3.21b | 3.44ab |
LF | 1.45b | 1.63a | 1.58ab | 1.56ab | 1.45b |
LC | 0.49b | 0.53a | 0.52ab | 0.51ab | 0.50b |
PH82 | 71.46b | 87.00a | 73.92b | 66.40b | 70.69b |
DCF | 46.26c | 45.25c | 58.83a | 53.33b | 53.19b |
HMS82 | 38.23ab | 42.83a | 37.94ab | 37.86ab | 36.00b |
DFS | 99.33b | 94.25c | 105.00a | 100.00ab | 104.07a |
NFPP | 309.26b | 272.00c | 261.58c | 333.20a | 308.83b |
NFCPP | 255.69b | 228.00c | 219.58c | 282.67a | 257.00b |
NUFCPP | 52.41a | 49.58a | 43.00a | 51.73a | 51.14a |
CD | 6.40a | 6.44a | 6.44a | 6.37a | 6.34a |
CL | 6.21a | 6.24a | 6.14a | 6.29a | 6.20a |
SL | 4.20ab | 4.35a | 3.97c | 4.05bc | 4.01c |
SB | 2.14ab | 2.33a | 2.10ab | 2.02b | 2.03b |
NSPC | 8.98ab | 9.02ab | 9.16ab | 9.46a | 8.55b |
TSW | 4.25b | 4.37b | 4.31b | 4.83a | 4.38b |
YPP | 9.70b | 8.93b | 8.76b | 12.90a | 9.64b |
Note: In a row, mean values with dissimilar letters are significantly different at 5% levels of probability. DGS Days to germination started; DE Days to 80% emergence; DBI Days to branch initiation; PH28 Plant height at 28 DAS (cm); NLPP Number of leaves plant–1 at 30 DAS; NB40 Number of branches at 40 DAS; PH40 Plant height at 40 DAS (cm); BD42 Base diameter at 42 DAS (mm); MBD42 Main branch diameter at 42 DAS (mm); DFF Days to first flowering; PH60 Plant height at 60 DAS (cm); NBPP60 Number of branches plant–1 at 60 DAS; DTBI Days to top branch initiation; LP Length of pedicel (mm); LF Length of flower (mm); LC Length of calyx (mm); PH82 Plant height at 82 DAS (cm); DCF Days to capsule formation; HMS82 Height of main stem at 82 DAS (cm); DFS Days to flowering stops; NFPP Number of flowers plant–1; NFCPP Number of filled capsules plant–1; NUFCPP Number of unfilled capsules plant–1; CD Capsule diameter at 115 DAS (mm); CL Capsule length at 115 DAS (mm); SL Seed length (mm); SB Seed breadth (mm); NSPC Number of seeds capsule–1; TSW 1000-seed weight (g); YPP Yield plant–1 (g).
PCA is useful for the identification of determinants of quantitative trait variability when a large number of accessions are to be accessed for several characters of morphological and agronomic importance. In the present investigation, the nine principal components with Eigen values greater than one were used and cumulatively they explained 70% of the total variability (
The correlation matrix of 30 measured traits was presented in
The breeding strategy is determined by the magnitude of genetic variation in agro–morphological traits related to yield. Genetic diversity and multivariate analysis research are critical for successful evaluation of genotypes. Genetic variability studies provide useful information that can be used as selection criteria in breeding programs [
Estimation of high heritability (h2b) along with high genetic advance is an efficient tool for predicting gain under selection rather than heritability alone [
Genetic improvement was done via selection and hybridization based on the genetic diversity between parents. Genetically diverse parents may result in the creation of desirable recombinants and transgressive segregants, which may lead to the improvement of good performing varieties. Cluster analysis set a large number of accessions into a small number of homogeneous clusters, facilitating the selection of diverse accessions. The study used 40 genotypes that were classified into five clusters based on divergence analysis, as shown in
The variance and the relative contribution of the measured traits to overall variability were estimated using principal component analysis (PCA) (
The present study’s findings demonstrate the existence of sufficient genetic diversity within and among genotypes, implying the possibility of future genetic improvement in linseed for economic characteristics. Cluster analysis revealed a clear separation of 40 genotypes into five clusters showing a significant genetic variability among them. The genotypes G3, G4, G6, G10 and G31 were shown to be promising for early flower and capsule formation in association with yield and yield attributing characters. The genotypes assembled in Cluster-II and III performed better in relation to morphological characters. According to different genetic variability estimation, a significant genetic variation was detected for most of the characteristics examined. The genetic variability study and multivariate analysis showed that the traits such as days to first flowering and capsule formation, days to emergence and germination, plant height at different DAS, number of flowers and filled capsules per plant and finally yield per plant were found important and could be effectively used for selection criteria for the development of linseed breeding. The genetic diversity of studied linseed genotypes detected in this study will aid useful information for further trait–specific breeding programs.
The authors extend their appreciation to Taif University for funding current work by Taif University Researchers Supporting Project No. (TURSP-2020/85), Taif University, Taif, Saudi Arabia and Ministry of Education, Government of the People’s Republic of Bangladesh.
Traits | Mean squares | LSD | |||
---|---|---|---|---|---|
Source | Genotype | Replication | Error | ||
df | 39 | 2 | 78 | ||
DGS | 1.640*** | 0.258 | 0.173 | 1.38 | |
DE | 1.776*** | 0.075 | 0.186 | 1.43 | |
DBI | 3.296*** | 3.233 | 0.627 | 2.62 | |
PH28 | 16.05*** | 23.63 | 2.659 | 5.39 | |
NLPP | 799.2* | 20227.6 | 487.1 | 72.9 | |
NB40 | 1.28ns | 0.56 | 0.865 | – | |
PH40 | 84.47*** | 27.22 | 11.45 | 11.18 | |
BD42 | 0.887ns | 6.07 | 0.61 | – | |
MBD42 | 0.509ns | 3.229 | 0.764 | – | |
DFF | 84.88*** | 30.50 | 12.688 | 11.77 | |
PH60 | 162.10*** | 210.9 | 36.89 | 20.07 | |
NB60 | 10.074ns | 6.273 | 6.99 | – | |
DTBI | 36.266*** | 14.058 | 7.896 | 9.28 | |
LP | 0.190* | 0.394 | 0.103 | 1.06 | |
LF | 0.082*** | 0.114 | 0.021 | 0.473 | |
LC | 0.003*** | 0.001 | 0.001 | 0.099 | |
PH82 | 192.16*** | 471.36 | 38.57 | 20.5 | |
DCF | 73.605*** | 45.025 | 15.632 | 13.06 | |
HMS82 | 67.14*** | 450.02 | 18.71 | 14.288 | |
DFS | 97.415*** | 96.308 | 21.257 | 15.231 | |
NFPP | 4210.1** | 4117.0 | 2223.9 | 155.44 | |
NFPCP | 3312.9** | 4299.1 | 1650.7 | 134.21 | |
NUFCPP | 104.32ns | 2228.16 | 99.21 | – | |
CD | 0.0941ns | 0.6415 | 0.093 | – | |
CL | 0.1729ns | 1.869 | 0.264 | – | |
SL | 0.153** | 0.0677 | 0.0753 | 0.906 | |
SB | 0.0671ns | 0.1755 | 0.0547 | – | |
NSPC | 0.8908ns | 2.155 | 0.698 | – | |
TSW | 0.368* | 0.596 | 0.206 | 1.50 | |
YPP | 11.16*** | 7.418 | 1.842 | 4.484 |
Note: ns = Non significant; *, **, *** Significant at 5%, 1% and 0.1% levels of probability, respectively.