| Literature DB >> 34071890 |
Messias de Carvalho1,2, Wiktor Halecki3.
Abstract
The aim of this study was to evaluate the adaptability of different genotypes of cowpea (Vigna unguiculata L. Walp.) in the edaphoclimatic conditions of a semi-arid region. In the experimental design, a completely randomized split-plot (2 × 8), with 3 repetitions (blocks) was used. The experiment comprised 7 new genotypes and 1 local genotype as the first main factor and application of insecticide as a secondary factor. Two-factor analysis of variance (two-way ANOVA) determined the differences between the treated and untreated plots. The results obtained in the experiment showed that the introduced genotypes V3 (IT07K-181-55), V7 (H4), and V5 (IT97K-556-4M) adapted well to the edaphoclimatic conditions of the study area and their yields were respectively 1019, 1015, and 841 kg/ha of grains in treated plots and 278, 517 and 383 kg/ha in untreated plots. Multivariate analysis revealed that the most important parameter was the germination rate. Finally, the best yield was obtained with the genotype V3 (IT07K-181-55), subjected to the use of insecticide, and with the V7 (H4) genotype in untreated plants. The findings presented in this research should be useful in crop system agricultural programs, particularly in the terms of selection of cultivating systems suitable for high-yielding cowpea.Entities:
Keywords: Vigna unguiculata L. Walp.; local genotypes; multivariate analysis; phytosanitary control; resistant plant
Year: 2021 PMID: 34071890 PMCID: PMC8228800 DOI: 10.3390/plants10061074
Source DB: PubMed Journal: Plants (Basel) ISSN: 2223-7747
Germination rate for examined genotypes. The average of the genotypes indicated by the letters, are not significantly different at the rate level of 5% and coefficient of variation (CV).
| Genotypes | Germination Rate (%) |
|---|---|
| IT07K-311-1 | 86 a |
| IT04K-221-1 | 78 ab |
| DIAMANTE | 77ab |
| IT07K-187-55 | 77 ab |
| IT89KD-288 | 75 b |
| H4 | 63 c |
| IT97K-556-4M | 53 c |
| Mean | 73 |
Figure 1Mean values of grain yield for genotypes treated (blue) and untreated (orange).
Figure 2CVA distinguished the best genotypes according to yield (grain). Cycles represent genotype H4, square determine genotype IT07K-181-55 and diamonds indicate genotype IT97K-556-4M. All data is prepared for treated with insecticide.
Figure 3Mean values of seed yield for genotypes treated (blue) and untreated (orange).
Figure 4PCA for the studied parameters. The most important factors were germination rate and seed yield. Kaiser-Mayer-Olkin (KMO) coefficient 0.62; p < 0.001.
Loading factors highlighted by PCA.
| Variable | Factor 1 | Factor 2 | Factor 3 | Factor 4 | Factor 5 | Factor 6 |
|---|---|---|---|---|---|---|
| Grain yield | −0.32 | 0.68 | 0.55 | −0.32 | 0.13 | −0.13 |
| Germination rate | 0.13 | 0.86 | −0.27 | 0.36 | 0.07 | 0.17 |
| Seed yield | 0.82 | 0.00 | −0.27 | −0.04 | 0.42 | −0.28 |
| Number of pods per plant | −0.79 | 0.17 | −0.41 | 0.08 | −0.21 | −0.36 |
| Pod weights | −0.73 | −0.04 | −0.46 | −0.35 | 0.30 | 0.20 |
| Threshing yield | −0.71 | −0.28 | 0.32 | 0.43 | 0.36 | −0.04 |
Eigenvectors computed by PCA.
| Variable | Factor 1 | Factor 2 | Factor 3 | Factor 4 | Factor 5 | Factor 6 |
|---|---|---|---|---|---|---|
| Grain yield | −0.20 | 0.59 | 0.57 | −0.43 | 0.19 | −0.24 |
| Germination rate | 0.08 | 0.75 | −0.28 | 0.49 | 0.10 | 0.31 |
| Seed yield | 0.52 | 0.002 | −0.28 | −0.05 | 0.61 | −0.51 |
| Number of pods per plant | −0.50 | 0.14 | −0.43 | 0.11 | −0.31 | −0.66 |
| Pod weights | −0.47 | −0.04 | −0.48 | −0.47 | 0.45 | 0.37 |
| Threshing yield | −0.45 | −0.24 | 0.33 | 0.59 | 0.53 | −0.07 |
Figure 5DCA quoted results for studied parameters between treated (red squares) and untreated (green diamonds) plant with insecticide. First axis explained 27.29% of variance and the second axis explained 23.40% of all the total variance.
Correlation for the most important parameters subjected by PCA.
| Variable | Grain Yield | Germination Rate | Seed Yield | Number of Pods Per Plant | Pod Weights | Threshing Yield |
|---|---|---|---|---|---|---|
| Grain yield | 1 | 0.26 | −0.3 | 0.13 | 0.08 | 0.12 |
| Germination rate | 0.26 | 1 | 0.15 | 0.1 | −0.08 | −0.25 |
| Seed yield | −0.3 | 0.15 | 1 | −0.52 | −0.39 | −0.52 |
| Number of pods per plant | 0.13 | 0.1 | −0.52 | 1 | 0.59 | 0.36 |
| Pod weights | 0.08 | −0.08 | −0.39 | 0.59 | 1 | 0.34 |
| Threshing yield | 0.12 | −0.25 | −0.52 | 0.36 | 0.34 | 1 |
Result of a generalized additive model for the most essential studied plant traits.
| Variable Index | DF | GAM Coefficient | Standard Error | Standard Score | Non-Linear | |
|---|---|---|---|---|---|---|
| Inception | 0 | 1.000000 | −1.27733 | 0.6999 | −1.82497 | - |
| Weight of 100 grain | 1 | 4.080600 | 0.00340 | 0.0046 | 0.73912 | 0.025104 |
| Seed yield | 2 | 4.115461 | 0.00191 | 0.0022 | 0.86949 | 0.045038 |
| Grain yield | 3 | 4.061803 | −0.05003 | 0.0438 | −1.14305 | 0.102087 |
| Weight of seeds selected | 4 | 3.912032 | 0.02932 | 0.0107 | 2.72839 | 0.008383 |
| Weight of seeds not selected | 5 | 4.006387 | 0.05173 | 0.0265 | 1.95248 | 0.005508 |
| Pod weights | 6 | 4.003659 | 0.10427 | 0.0253 | 4.12764 | 0.874075 |
| Number of harvested plants | 7 | 3.955695 | −0.12843 | 0.0324 | −3.96647 | 0.087135 |
| Germination rate | 8 | 3.975686 | −1.29209 | 569.9148 | −0.00227 | 0.000000 |
| Number of live plants on the central lines | 9 | 4.061591 | −0.00001 | 0.0000 | −0.13349 | 0.000328 |
| Number of live plants in the border lines | 10 | 4.032929 | 0.00024 | 0.0004 | 0.64662 | 0.000000 |
Figure 6(a). GAM for germination rate as covariate and weight of 100 grain as response variable during abundance of Zonocerus variegates. (b). GAM for number of live plants on the central lines as covariate and weight of 100 grain as response variable during no occurrence of Zonocerus variegates. (c). GAM for number of harvested plants on the central lines as covariate and weight of 100 grain as response variable. (d). GAM for number of live plants in the border lines as covariate and weight of 100 grain as response variable.
Multiply regression for crop parameters defined by four environmental factors.
| Coefficient | Standard Error | t |
| R2 | ||
|---|---|---|---|---|---|---|
| Constant | 1084.30 | 2812.90 | 0.39 | 0.70 | ||
| Weight of seeds not selected | 65.93 | 50.32 | 1.31 | 0.20 | 0.50 | |
| Number of pods per plant | 12.20 | 319.51 | 0.04 | 0.97 | 0.19 | |
| Grain yield | Number of harvested plants | −45.60 | 55.79 | −0.82 | 0.42 | 0.05 |
| maturity (95%) | 19.99 | 37.61 | 0.53 | 0.60 | 0.04 | |
| Pod weights | −7.18 | 39.44 | −0.18 | 0.86 | 0.47 | |
| weight of 100 grain | 288.94 | 228.62 | 1.26 | 0.22 | 0.31 | |
| Constant | 7.68 | 0.33 | 23.23 | 0.00 | ||
| Weight of seeds not selected | 0.01 | 0.01 | 1.07 | 0.29 | 0.07 | |
| Number of pods per plant | −0.05 | 0.04 | −1.32 | 0.20 | 0.11 | |
| Risk of aphid-mosaic virus disease | Number of harvested plants | 0.01 | 0.01 | 1.88 | 0.07 | 0.14 |
| Maturity (95%) | −0.07 | 0.00 | −15.85 | 0.04 | 0.88 | |
| Pod weights (gr) | 0.00 | 0.00 | −1.06 | 0.30 | 0.11 | |
| Weight of 100 grain | −0.06 | 0.03 | −2.19 | 0.04 | 0.19 | |
| Constant | −0.46 | 3.28 | −0.14 | 0.89 | ||
| Weight of seeds not selected | −0.01 | 0.06 | −0.17 | 0.87 | 0.80 | |
| Number of pods per plant | 0.33 | 0.37 | 0.90 | 0.38 | 0.40 | |
| Weight of selected seeds | Number of harvested plants | 0.01 | 0.07 | 0.13 | 0.90 | 0.16 |
| maturity (95%) | 0.00 | 0.04 | −0.10 | 0.92 | 0.05 | |
| Pod weights | 0.14 | 0.05 | 2.98 | 0.01 | 0.85 | |
| weight of 100 grain | 0.20 | 0.27 | 0.74 | 0.46 | 0.40 | |
| Constant | 2.15 | 0.77 | 2.78 | 0.01 | ||
| Weight of seeds not selected | 0.01 | 0.01 | 0.51 | 0.62 | 0.24 | |
| Number of pods per plant | −0.10 | 0.09 | −1.11 | 0.28 | 0.29 | |
| Number of harvested plants | −0.01 | 0.02 | −0.64 | 0.53 | 0.11 | |
| Maturity (95%) | 0.03 | 0.01 | 3.23 | 0.35 | 0.03 | |
| Pod weights | −0.01 | 0.01 | −0.76 | 0.46 | 0.23 | |
| weight of 100 grain | −0.17 | 0.06 | −2.71 | 0.01 | 0.35 |
Climate conditions observed from September 2017 to February 2018 throughout the experiment.
| Year/2017–2018 | Precipitation (mm) | Average Temperature °C | Relative Humidity (%) | Insolation (Calories in cm3) |
|---|---|---|---|---|
| September | 36.0 | 27.5 | 71.4 | 590.2 |
| October | 214.0 | 27.4 | 76.7 | 622.1 |
| November | 206.0 | 27.4 | 75.9 | 671.6 |
| December | 234.6 | 27.4 | 82.0 | 568.3 |
| January | 99.8 | 27.9 | 81.8 | 731.5 |
| February | 94.2 | 27.1 | 77.2 | 641.1 |
Source: Experimental Station of the Institute of Agricultural Development (IDA) Dange-Quitexe municipality.
Figure 7Experimental layout using split-plot design in the study area.