Figure 1.

Figure 2.

Figure 3.

Figure 4.

Weather information of the study area during the study (July-December)_
| Parameters | 2023 | 2024 |
|---|---|---|
| Mean maximum temperature [ºC] | 31.4 | 31.5 |
| Mean minimum temperature [ºC] | 23.5 | 3.0 |
| Mean precipitation [mm/day] | 3.6 | 2.9 |
| Mean relative humidity [%] | 81.7 | 77.6 |
| Total precipitation [mm] | 582.0 | 509.5 |
Growth (across different plant ages) and yield of maize as influenced by the cropping system_
| Cropping systems | Plant height [cm] | Number of leaves | ||||||
|---|---|---|---|---|---|---|---|---|
| 4 WAS | 6 WAS | 8 WAS | 10 WAS | 4 WAS | 6 WAS | 8 WAS | 10 WAS | |
| Sole | 25.43 a | 55.19 a | 81.33 a | 108.48 a | 6.42 a | 7.47 a | 9.81 a | 10.63 a |
| Maize + ARTKEN 211 | 25.28 a | 51.52 a | 80.73 a | 112.71 a | 6.08 a | 7.61 a | 9.92 a | 10.83 a |
| Maize + IFEKEN 400 | 26.47 a | 53.96 a | 83.37 a | 121.84 a | 6.28 a | 7.33 a | 9.83 a | 10.56 a |
| Maize + IFEKEN 400 DI | 27.06 a | 54.19 a | 78.94 a | 120.63 a | 6.4 a | 7.34 a | 9.76 a | 10.75 a |
| Leaf area [cm2] | Stem diameter [cm] | |||||||
| 4 WAS | 6 WAS | 8 WAS | 10 WAS | 4 WAS | 6 WAS | 8 WAS | 10 WAS | |
| Sole | 55.10 a | 232.26 a | 349.59 a | 435.36 a | 0.61 a | 1.22 a | 1.37 a | 1.97 a |
| Maize + ARTKEN 211 | 50.72 a | 186.90 a | 316.45 a | 466.77 a | 0.51 a | 1.21 a | 1.37 a | 1.63 a |
| Maize + IFEKEN 400 | 45.51 a | 198.35 a | 310.68 a | 406.11 a | 0.54 a | 1.19 a | 1.37 a | 1.64 a |
| Maize + IFEKEN 400 DI | 52.94 a | 187.20 a | 310.66 a | 403.91 a | 0.57 a | 1.23 a | 1.42 a | 1.63 a |
| Grain yield [t/ha] | 100-seed weight [kg] | |||||||
| 12 WAS | 12 WAS | |||||||
| Sole | 1.11 a | 0.014 a | ||||||
| Maize + ARTKEN 211 | 1.25 a | 0.012 a | ||||||
| Maize + IFEKEN 400 | 1.40 a | 0.013 a | ||||||
| Maize + IFEKEN 400 DI | 1.60 a | 0.013 a | ||||||
Mean square values from the analysis of variance for growth and yield components of maize intercropped with three kenaf varieties under two spacing in two seasons_
| Sources of variation | Degree of freedom | Plant height | Stem diameter | Number of leaves | Leaf area | Grain yield | 100-seed weight |
|---|---|---|---|---|---|---|---|
| Cropping system (CS) | 3 | 177.81 ns | 0.12 ns | 0.12 ns | 9243.86 ns | 0.52 ns | 0.001 ns |
| Season (S) | 1 | 14763.36*** | 0.09 ns | 8.83*** | 1952.52 ns | 7.04*** | 0.001 ns |
| Spacing (SP) | 2 | 823.85* | 0.02 ns | 1.78 ns | 14662.04 ns | 0.18 ns | 0.006* |
| CS × S | 3 | 109.07 ns | 0.36 ns | 2.67** | 10453.80 ns | 0.84 ns | 0.001 ns |
| CS × SP | 3 | 108.09 ns | 0.31 ns | 2.59** | 7703.12 ns | 0.21 ns | 0.004 ns |
| SP× S | 1 | 3740.18*** | 0.58 ns | 6.44** | 66852.76*** | 0.24 ns | 0.002 ns |
| CS × SP× S | 3 | 386.31 ns | 0.21 ns | 0.58 ns | 38549.98 ns | 0.22 ns | 0.000 ns |
Mean effect of seasonal and spacing variation on growth and yield of maize intercropped with kenaf under two spacing in two seasons_
| Sources of variation | Plant height [cm] | Number of leaves | Leaf area [cm2] | Stem diameter [cm] | Grain yield [t/ha] | 100-seed weight [kg] |
|---|---|---|---|---|---|---|
| average over 4–10 WAS | at 12 WAS | |||||
| Spacing | ||||||
| 50 cm × 15 cm | 67.124 b | 8.472 a | 241.79 a | 1.226 a | 1.402 a | 0.014 a |
| 50 cm × 25 cm | 71.267 a | 8.665 a | 259.27 a | 1.208 a | 1.278 a | 0.012 b |
| Season | ||||||
| First | 77.965 a | 8.354 b | 247.34 a | 1.239 a | 0.957 b | 0.014 a |
| Second | 60.427 b | 8.783 a | 253.72 a | 1.195 a | 1.723 a | 0.013 a |
Effect of season, variety, cropping system and spacing on growth, yield and yield components of three kenaf (Hibiscus cannabinus L_) varieties intercropped with maize at two spacing dimensions in two seasons_
| Treatments | Plant height [cm] | Number of leaves | Stem diameter [cm] | Number of capsules/plant | Number of seeds/capsule | Seed yield [t/ha] | Core yield [t/ha] | Bast fibre yield [t/ha] |
|---|---|---|---|---|---|---|---|---|
| average over 4–10 WAS# | at 10 WAS | |||||||
| Kenaf varieties | ||||||||
| ARTKEN 211 | 50.158 a | 41.764 a | 0.853 a | 22.729 a | 17.817 a | 1.815 a | 2.229 a | 0.812 a |
| IFEKEN 400 | 45.090 b | 38.124 a | 0.723 b | 22.271 a | 18.073 a | 1.961 a | 2.077 a | 0.744 a |
| IFEKEN DI 400 | 48.041 a | 42.273 a | 0.787 a | 25.438 a | 17.429 a | 2.355 a | 2.100 a | 1.028 a |
| Season | ||||||||
| First | 51.628 a | 41.734 a | 0.675 b | 30.347 a | 19.614 a | 3.262 a | 0.959 b | 0.811 a |
| Second | 43.897 b | 39.706 a | 0.900 a | 16.611 b | 15.932 b | 0.825 b | 3.311 a | 0.912 a |
| Cropping system | ||||||||
| Sole | 45.250 b | 39.981 a | 0.749 b | 22.438 a | 18.136 a | 1.963 a | 2.245 a | 0.777 a |
| Intercrop | 50.275 a | 41.458 a | 0.826 a | 24.521 a | 17.410 a | 2.123 a | 2.025 a | 0.947 a |
| Spacing | ||||||||
| 0.50 m × 0.15 m | 49.081 a | 42.623 a | 0.828 a | 23.028 a | 18.838 a | 1.963 a | 2.843 a | 1.185 a |
| 0.50 m × 0.25 m | 46.445 b | 38.817 a | 0.747 b | 23.931 a | 16.708 b | 2.124 a | 1.427 b | 0.538 b |
Mean square values from the analysis of variance for growth and yield parameters of kenaf varieties intercropped with maize under two spacing dimensions in two seasons_
| Sources of variation | Degree of freedom | Plant height | Stem diameter | Number of leaves | Number of seeds/capsule | Seed yield | Number of capsules/plant | Core yield | Bast fibre yield |
|---|---|---|---|---|---|---|---|---|---|
| Variety (V) | 2 | 621.87** | 0.40** | 491.67 ns | 2.52 ns | 1.88 ns | 70.29 ns | 0.16 ns | 0.53 ns |
| Cropping system (CS) | 1 | 1817.96*** | 0.42** | 157.04 ns | 9.50 ns | 0.46 ns | 78.13 ns | 0.87 ns | 0.87 ns |
| Season (S) | 1 | 4303.21*** | 3.63*** | 296.06 ns | 244.02*** | 106.95*** | 3396.25*** | 99.55*** | 0.18 ns |
| Spacing (SP) | 1 | 500.20* | 0.48** | 1042.72 ns | 81.06** | 0.47 ns | 14.67 ns | 36.11*** | 7.54** |
| V × CS | 2 | 37.97 ns | 0.10 ns | 17.23 ns | 0.92 ns | 4.46 ns | 43.16 ns | 0.50 ns | 0.71 ns |
| V × S | 2 | 482.69* | 0.01 ns | 747.27 ns | 1.62 ns | 1.58 ns | 85.68 ns | 0.01 ns | 1.35 ns |
| V × SP | 2 | 2.23 ns | 0.04 ns | 142.27 ns | 7.42 ns | 2.54 ns | 3.67 ns | 1.01 ns | 1.37 ns |
| CS × S | 1 | 302.20 ns | 0.15 ns | 370.52 ns | 1.76 ns | 0.08 ns | 39.01 ns | 0.60 ns | 0.67 ns |
| CS × SP | 1 | 835.21** | 0.03 ns | 126.23 ns | 31.67 ns | 0.94 ns | 105.13 ns | 1.96 ns | 0.24 ns |
| S × SP | 1 | 3158.47*** | 0.11 ns | 3222.26** | 0.01 ns | 11.12* | 243.84* | 17.61 ns | 0.15 ns |
| V × CS × S | 2 | 51.29 ns | 0.02 ns | 90.48 ns | 14.19 ns | 5.66 ns | 119.21 ns | 1.49 ns | 1.48 ns |
| V × CS × SP | 2 | 37.95 ns | 0.01 ns | 375.40 ns | 0.12 ns | 1.69 ns | 73.26* | 2.70 ns | 2.16 ns |
| V × S × SP | 2 | 13.61 ns | 0.05 ns | 210.87 ns | 2.97 ns | 2.67 ns | 32.67 ns | 0.42 ns | 0.80 ns |
| CS × S × SP | 1 | 84.34 ns | 0.08 ns | 36.13 ns | 0.002 ns | 0.53 ns | 70.01 ns | 0.68 ns | 0.89 ns |