The authors have declared that no competing interests exist.
A field experiment was carried out at the Teaching and Research Farms of The Federal University of Technology Akure to evaluate the responses of cassava varieties to time of planting in plantain-based intercropping system in the rainforest zone of Nigeria. The objectives were to identify the more compatible cassava variety for intercrop with plantain examine e the appropriate time to introduce cassava varieties into plantain/cassava intercrop and to identify the more compatible cassava variety for intercrop with plantain. The experiment involved the use of two varieties of cassava (TME 419 non branching and TMS 98/0581 moderately branched) planted at spacing of 1 x 1 m into the alleys of false horn plantain variety space at 3 x 2 m. The treatments were sole plantain, sole cassava varieties (TME 419 poorly branched variety and TMS 0581 branching variety), plantain + he respective cassava varieties (TME 419 and TMS 98/0581) at the same time, and plantain + the respective cassava varieties (TME 419 and TMS 98/0581) at 4 weeks after planting>the treatment plot size was 9 m x 6 m. The plantains and the two cassava varieties were planted sole as the control treatments. The introduction of cassava into plantain as intercrop was carried out at different times which were; at the same time with plantain, and at four (4) weeks after planting plantain. Data on growth parameters such as; plant height, pseudo-stem girth, number of leaves were taken for plantains, while plant height, stem girth, number of leaves, number of branches, height at branching were taken for cassava at 4, 8, 12, 16, 20 and 24 weeks after planting (WAP). Yield parameters such as; bunch weight, number of fingers, number of hands, length of fingers, girth of fingers, weight of hands, weight of fingers were taken for plantains while number of tubers, weight of tubers, girth of tubers, length of tubers, fresh root yield, shoot biomass, were taken for cassava at harvest. The data collected were subjected to statistical analysis. The results showed a higher growth and yield performance for TME419 (49.2 t/ha) and TMS98/0581 (45.7 t/ha) planted sole, and TME 419 (39.5 t/ha) intercropped at planting compared to TMS 98/0581 (24.4 t/ha) intercropped at planting, TME 419 (21.7 t/ha) and TMS 98/0581 (15.7 t/ha) intercropped at 4 week after planting (WAP), respectively. But there was no significant difference (P<0.05) recorded for the growth of plantain, whereas the yield of sole plantain was higher and differed significantly (P<0.05) from the yields of intercropped plantain. All the treatment combinations had land equivalent ratio (LER) and area time equivalent ratio (ATER) greater than 1. Plantain + TME 419 intercropped at the same time recording the highest LER and ATER (1.48 and 1.5) while plantain + TMS 98/0581 had the least 1.11 and 1.14 respectively. The cost benefit analysis for the treatment combinations showed that TME 419 planted sole had the highest return of ₦3.567 per ₦1 invested, TME 419 intercropped at the same time gave a return of ₦3.416 per ₦1 invested, which was greater than other intercropped treatments. Intercropping cassava with plantain at the same time, as well as the use of TME 419 variety gave the best performance in terms of growth, yield, land equivalent ratio, area time equivalent ratio and returns on investment. This combination are recommended for plantain-based intercropping system involving cassava in the study area.
The English word plantain apparently was derived from the Spanish plátano
The area harvested of plantains in West Africa increased fairly steadily and nearly doubled between 1990 and 2011, from approximately 955,000 hectares (ha) to 1,700,000 ha In 2011, 12.46 million metric tons (MT) of plantains were produced, representing 32.0% of worldwide production
Plantain is a carbohydrate source and the vitamin C content of plantain is very similar to those of sweet potatoes, cassava, though the concentration may vary with the crop, maturity at harvest, soil and farming conditions
Prominent among major characteristics of plantain is its ability to survive extended periods of drought unlike most other crops. It can also grow well under a wide range of soil conditions, with its fruits being produced almost all year round. Almost all parts of the plant have one economic use or another and may be harvested for household use or sale to raise income. Plantain also co-exists well with a wide range of plants and trees, except allelopathic plants and is traditionally grown in mixed cropping systems
Cassava (
Due to ever increasing human population especially in Africa leading to diminishing agricultural land sizes, intercropping, with its advantages of risk minimization, reduction of soil erosion, increased food security should be practiced. Most crops can now be intercropped including fruit trees, and therefore farmers with small pieces of land should no longer worry
The objectives of the experiment are to determine the appropriate time to introduce cassava varieties in a plantain/cassava intercrop and Identify a more compatible cassava variety for intercrop with plantain.
The research experiment was conducted at the Teaching and Research Farm of the Federal University of Technology Akure (70 16’ N, 50 12’ E) located in the rainforest area of southwestern Nigeria. The location is characterized by bimodal pattern of rainfall with an annual mean of about 1300 mm with mean temperature 270C, and the climate is sub-humid type. The total size of the experimental plot was 80 x 40 m, the land is slightly slope with a pH of 6.5, and the land has been under fallow for some years. The textural class of the soil is sandy clay loam with 35.5% clay, 11.3% silt, and 58.2% sand. The fauna observed on the land were termites and different kinds of ants as this was evident due to the presence of termite mound and ant hill in the experimental site. Larger holes made by small mammals (rodents) were also observed in the land. This is an indication that the soil possibly has a good structure and it is well aerated.
The experimental site has over the years been used for cassava production and was left fallowed for about six years with weeds such as
The planting materials used were sourced from the Teaching and Research Farm of the Federal University of Technology Akure. The plantain suckers used were sword suckers of the false horn cultivar with medium sized pseudo stem.
cassava stems were also obtained from the Teaching and Research Farms FUTA. Two improved varieties developed by IITA, TME 419 (a non-branching variety), and TMS98/ 0581 (an averagely branching variety) were used for the experiment.
A mini excavator was used to uproot the trees and shrubs, then the leaves were allowed to fall off, afterwards chainsaw was used to cross cut the uprooted trees into logs and then moved manually out of the field. No tillage operation was carried out. The weeds left on the field were sprayed with a broad spectrum herbicide (
The experiment was made up of seven treatments arranged in a Randomized Complete Block Design (RCBD) with three (3) replications. Plot size measured 54 m2 (9 x 6 m) with 2 m alley between each plot and 3 m walkway between the blocks.
Soil samples collected from 0 – 30 cm depth, using a soil auger at pre-planting and at crop maturity were subjected to laboratory analysis to determine the physical properties; soil texture, and chemical properties; pH, nitrogen ,phosphorus, potassium, organic carbon, organic matter ,calcium, magnesium, and sodium.
Pre-cropping physical and chemical analysis of the experimental soil was carried out before land preparation and repeated at the harvest to determine the nutrient status of the soil. The soil samples were air dried, crushed and sieved to pass through a 2 mm sieve after which physical analysis was carried out using the hydrometer method (
Treatments | Nutrient elements | |||||||
pH | N | OC | P | K | Ca | Mg | Na | |
(H2O) | (g/kg) | Mg/kg | (cmol/kg) | |||||
Pre-planting | 6.54a | 3.3e | 22.7b | 5.42d | 0.21b | 2.1cd | 0.99ab | 0.26e |
After treatment | ||||||||
TME419 (sole) | 4.62b | 6.0b | 20.5c | 9.09cd | 0.26ab | 2.2cd | 1.00a | 0.34cd |
TMS98/0581 (sole) | 4.61b | 6.8a | 18.0de | 12.38abc | 0.30a | 2.5b | 1.1a | 0.32d |
Plantain (sole) | 4.63b | 7.1a | 24.7a | 12.10abc | 0.31a | 2.90a | 1.13a | 0.41a |
TME419 + plantain at same time | 4.46b | 5.4c | 18.1de | 11.68abc | 0.30a | 2.3bc | 1.1a | 0.38abc |
TMS98/0581 + plantain at same time | 4.47b | 5.0c | 19.5cd | 11.57bc | 0.31a | 1.97d | 0.60b | 0.39ab |
TME419 + plantain at 4 weeks | 4.17c | 5.4c | 20.5c | 15.76a | 0.29a | 2.1cd | 0.90ab | 0.36bcd |
TMS98/0581 + plantain at 4 weeks | 4.23c | 4.3d | 17.2e | 13.65ab | 0.29a | 2.0d | 0.80ab | 0.41a |
Mean in the same column followed by the same letters are not significantly different at (P <0.05) according to Tukey comparisons.
Sand fractions: 582g/kg, Silt fraction:113g/kg and Clay fraction:305g/kg
The plantains were planted in September 2015 and cassava planted alongside the plantains in treatments four and five, while cassava was introduced into treatments six and seven four weeks after planting of the plantain.The plantain suckers were pared with sharp knife in order to remove any possible pest (weevil) embedded in the corm, then treated with nematicide/insecticide (carbofuran) dissolved in water in order to prevent termite and banana weevil attack. The suckers were planted in holes 30 cm x 30 cm x 30 cm and covered with top soil at a spacing of 3 m x 2 m resulting in 16 plants per plot of 54 m2, hence giving 1667 stands per hectare equivalent.
The cassava cuttings were treated with insecticide (cabofuran) to prevent termite attack before planting sole and inter-planting them with the plantains at spacing of 1m x 1m. The spacing resulted in 70 plants per sole plot (10,000 plant stands per hectare equivalent), and 54 plants in intercrop (8333 plant stands per hectare equivalent)
Sole plantain as control; Sole cassava (TME 419) poorly branched variety; Sole cassava (TMS 98/0581) branched variety; Plantains + TME 419 at the same time; Plantains + TMS 98/0581 at the same time; Plantain + TME 419 at 4 weeks after planting; and Plantain + TMS 98/0581 at 4 weeks after planting.
Cultural practices carried out on the cassava/plantain field. This include weeding which was carried out with the use of herbicides (glyphosate and diuron). The spraying of the field commenced before planting and was done at an interval of six weeks during the rainy season, while it was not sprayed at all during the dry season. Prior to the spraying of the field, the base of the plantain stands were cleared in a ring form so as to avoid contact with the herbicide in use. Chemical method of weeding was adopted because manual weeding may cause damage to the plantain roots which is usually growing within the top soil region. Sucker management was carried out by removing excess suckers from each plantain stand. This was carried out with the use of cutlass at the base of the plant close to the parent. Cassava was harvested manually by pulling the roots from the ground, and then a cutlass was used to cut off the tubers from the stem. Plantains were harvested at maturity by first cutting the pseudo stem, then bunches were cut off. The pseudo-stem cut was left to rot on the ground in order to add organic matter to the soil.
Data were taken from four randomly selected plantain and cassava stands, beginning from 4 weeks after planting. The data taken from plantains were pseudo-stem height and girth, number of leaves/plant while data taken for the yield of plantain at harvest are; bunch weight (kg), number of finger. The data collected on cassava growth and yield parameters were; stem height and girth, number of leaves/plant, number and height at stem branching. The data taken for cassava at harvest were length of tuber (cm), number of tubers, weight of tuber (kg), girth of tuber, root biomass, shoot biomass, dry matter analysis using oven drying method: 100 g of fresh tuber was placed in the oven at 1050C for 24 hours then it was removed and weighed.
The Land Equivalent Ratio was calculated at harvest by dividing the yields obtained from sole crops with those of the intercropped. This will be carried out mathematically by using the formula below;
LER = Lx + Ly = Ax/Px + Ay + Py
Where
A concept called "area time equivalency ratio" (ATER) has been developed by Hiebsch
tmi= growing period of crop
Yii= yield (t/ha) of crop
n= total number of crops in the system
Data collected on plantain and cassava growth and yield parameters were analyzed using the Analysis of Variance (ANOVA) and the means were compared using Tukey Test at the 5% level of probability. Minitab version 17 was used.
(
Varietal Response and Effects of Planting Time on Growth Parameters of Cassava
The varietal response and effects of planting time on cassava plant height is presented in
Treatments | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
TME419 (sole) | 21.00b | 105.08a | 124.67a | 136.75a | 162.75a | 190.00a |
TMS98/0581 (sole) | 18.41b | 63.50b | 93.67abc | 101.00abc | 119.50abc | 133.25abc |
Plantain + TME419 (0wap) | 17.17b | 100.50a | 117.33ab | 122.67ab | 143.75ab | 167.08ab |
Plantain + TMS98/0581 (0wap) | 17.41b | 55.75bc | 77.00bcd | 88.00bc | 100.58abc | 116.67bc |
Plantain + TME419 (4wap) | 30.75a | 49.41bc | 59.50cd | 75.91bc | 91.67bc | 129.20abc |
Plantain + TMS98/0581 (4wap) | 22.83b | 35.58c | 42.58d | 53.75c | 63.08c | 80.67c |
Means in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons
Treatments | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
TME419 (sole) | 10.67ab | 32.91a | 40.25a | 31.50a | 46.17a | 55.00abc |
TMS98/0581 (sole) | 10.25b | 31.58a | 42.67a | 39.17a | 53.63a | 76.65a |
Plantain + TME419 (0wap) | 9.33b | 29.83a | 36.75ab | 28.58a | 40.08ab | 46.00bc |
Plantain + TMS98/0581 (0wap) | 10.67ab | 32.67a | 40.25a | 35.17a | 50.91a | 64.75ab |
Plantain + TME419 (4wap) | 12.08a | 19.33b | 22.50bc | 26.25a | 27.83b | 39.68c |
Plantain + TMS98/0581 (4wap) | 11.08ab | 17.67b | 15.75c | 23.58a | 26.75b | 37.75c |
Mean in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons.
Treatment | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
TME419 (sole) | 0.68a | 1.67a | 1.80a | 1.89ab | 1.93ab | 2.03a |
TMS98/0581 (sole) | 0.67a | 1.40ab | 1.75a | 1.94a | 2.00a | 2.03a |
Plantain + TME419 (0wap) | 0.72a | 1.50a | 1.68ab | 1.74ab | 1.75abc | 1.80ab |
Plantain + TMS98/0581 (0wap) | 0.68a | 1.30ab | 1.44abc | 1.60abc | 1.64abc | 1.69ab |
Plantain + TME419 (4wap) | 0.82a | 1.05bc | 1.16bc | 1.20bc | 1.30bc | 1.60ab |
Plantain + TMS98/0581 (4wap) | 0.70a | 0.84c | 1.02c | 1.03c | 1.09c | 1.49b |
Means in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons.
The data presented in
Treatments | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
Plantain (sole) | 8.00a | 10.41a | 9.50b | 3.25a | 2.83a | 2.58a |
Plantain + TME419 (0wap) | 8.08a | 11.17a | 10.58a | 3.50a | 2.67a | 2.00a |
Plantain + TMS98/0581 (0wap) | 8.67a | 11.25a | 11.17a | 3.41a | 2.58a | 2.25a |
Plantain + TME419 (4wap) | 8.00a | 10.91a | 10.58a | 3.67a | 3.08a | 2.91a |
Plantain + TMS98/0581 (4wap) | 8.16a | 11.17a | 10.50ab | 3.58a | 2.83a | 2.67a |
Means in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons.
Treatment | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
Plantain (sole) | 53.33a | 101.25a | 106.83a | 107.81a | 109.17a | 109.91a |
Plantain + TME419 (0wap) | 58.43a | 109.37a | 116.51a | 117.08a | 117.25a | 118.91a |
Plantain + TMS98/0581 (0wap) | 56.70a | 105.27a | 110.68a | 111.08a | 111.91a | 113.75a |
Plantain + TME419 (4wap) | 46.17a | 97.85a | 102.77a | 107.50a | 108.25a | 112.00a |
Plantain + TMS98/0581 (4wap) | 53.75a | 104.93a | 113.43a | 114.50a | 115.33a | 116.48a |
Means in the same column followed by the same letter are not significantly different at (P<0.05) according to Tukey comparisons.
Treatment | Weeks after planting | |||||
4 | 8 | 12 | 16 | 20 | 24 | |
Plantain (sole) | 4.07a | 7.77a | 7.70a | 7.35a | 7.21a | 7.04a |
Plantain + TME419 (0wap) | 5.40a | 8.74a | 8.37a | 8.20a | 7.74a | 7.38a |
Plantain + TMS98/0581 (0wap) | 4.95a | 8.25a | 7.48a | 7.44a | 7.35a | 6.68a |
Plantain + TME419 (4wap) | 4.47a | 7.60a | 7.52a | 7.51a | 7.38a | 7.38a |
Plantain + TMS98/0581 (4wap) | 4.97a | 7.85a | 7.84a | 7.77a | 7.50a | 7.20a |
Means in the same column followed by the same letter are not significantly different at (P<0.05)according to Tukey comparisons.
The data presented in
Treatments | Tuber | Tuber girth (cm) | Tuber length (cm) | Number of tubers | Fresh root yield (kg/plant) | Shoot biomass (kg) | Root yield (t/ha) | Dry matter yield (%) |
weight (kg) | ||||||||
TME419 (sole) | 0.81a | 6.28a | 44.25a | 9.58ab | 4.92a | 4.18a | 49.2a | 27.5c |
Plantain + TME419 (0wap) | 0.78a | 6.14a | 36.25ab | 10.58a | 4.74a | 4.33a | 39.5a | 22.6d |
Plantain + TME419 (4wap) | 0.70a | 5.15b | 33.58b | 5.83c | 2.93b | 4.00a | 21.7b | 30.2a |
TMS98/0581 (sole) | 0.71a | 6.44a | 31.97b | 11.11a | 4.57a | 5.00a | 45.7a | 20.1e |
Plantain + TMS98/0581 (0wap) | 0.58ab | 6.24a | 32.44b | 10.52a | 2.62b | 4.24a | 24.4b | 20.4e |
Plantain + TMS98/0581 (4wap) | 0.31b | 5.10b | 21.33c | 7.41bc | 1.83b | 3.50a | 15.7b | 29.3b |
Means in the same column followed by the same letters are not significantly different at (P <0.05) according to Tukey comparison
Theresults further showed that TME419 and TMS98/0581 planted sole, alongside TME419 and TMS98/0581 intercropped at same time did not differ significantly (P<0.05) in tuber girth, while TME419 and TMS98/0581 intercropped at 4 weeks differed significantly (P<0.05) from those intercropped at the same time as indicated with (letter b) in
The data recorded in
Treatments | Number of branches | Height at branching (cm) |
TME419 (sole) | 0.33a | 17.91d |
TMS98/0581(sole) | 2.00a | 58.75a |
Plantain + TME419 (0wap) | 0.17b | 19.1c |
Plantain + TMS98/0581 (0wap) | 1.58ab | 33.67b |
Plantain + TME419 (4wap) | 0.00b | 0.00f |
Plantain + TMS98/0581 (4wap) | 0.83ab | 13.83e |
Means in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons.
The results presented in
Treatment | Weight of bunch (kg/plant) | Number of fingers/bunch | Number of hands/bunch | Length of fingers (cm) | Girth of fingers (cm) | Weight of hands (kg) | Weight of fingers (kg) | Bunch weight (t/ha) |
Plantain sole | 10.53a | 28.33a | 5.67a | 26.00a | 4.53a | 2.13a | 0.53a | 17.55a |
Plantain + TME419 (0Wap) | 7.11b | 26.33a | 6.00a | 26.00a | 4.07a | 1.63ab | 0.37b | 11.86b |
Plantain + TMS98/0581 (0Wap) | 7.47b | 24.67a | 5.41a | 22.91ab | 4.18a | 1.53b | 0.50ab | 12.44b |
Plantain + TME419 (4Wap) | 8.30b | 27.00a | 6.00a | 26.33a | 4.13a | 1.68ab | 0.48ab | 13.83b |
Plantain + TMS98/0581 (4Wap) | 8.08b | 26.67a | 6.00a | 24.33ab | 4.33a | 2.10ab | 0.53a | 13.47b |
Means in the same column followed by the same letter are not significantly different at (P <0.05) according to Tukey comparisons.
Plantain and TME419 planted at the same time had the highest LER of 1.48, while plantain and TMS98/0581 intercropped at the same time had an LER of 1.23 (
Treatment | Yield t/ha | LER | ATER | |
Bunch | Fresh root | |||
Plantain sole | 17.55 | - | ||
TME419 sole | 49.2 | - | ||
TMS98/0581 sole | 45.7 | - | ||
Plantain + TME419 0WAP | 11.86 | 39.5 | 1.48 | 1.5 |
Plantain + TMS98/0581 0WAP | 12.44 | 24.4 | 1.23 | 1.17 |
Plantain + TME419 4 WAP | 13.83 | 21.7 | 1.22 | 1.34 |
Plantain + TMS98/0581 4WAP | 13.47 | 15.7 | 1.11 | 1.14 |
(
Plantain (sole) | TME419 (sole) | TMS98/0581 (sole) | Plantain+TME419 at same time | Plantain+TMS98/0581 at same time | Plantain+TME419 at 4 weeks | Plantain+TMS98/0581 | |
at 4 weeks | |||||||
A. Yield t/ha | |||||||
i. Plantain | 7.55 | - | - | 11.86 | 12.44 | 13.83 | 13.47 |
ii. Cassava t/ha | 49.2 | 45.7 | 39.5 | 24.4 | 21.7 | 15.7 | |
iii. Price ₦ | 50,000 | 16,000 | 16,000 | 50,000 + 16,000 | 50,000 + 16,000 | 50,000 + 16,000 | 50,000 + 16,000 |
iv. Gross income ₦ | 877,500 | 787,200 | 731,200 | 1,225,000 | 1,012,400 | 1,038,700 | 924,700 |
B. Variable cost ₦ | |||||||
Land clearing/ha | |||||||
Tree felling (mini excavator)/h | 60,000 | 60,000 | 60,000 | 60,000 | 60,000 | 60,000 | 60,000 |
Log removal (manual)/ha | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 |
Digging of hole/ha | 17,000 | - | - | 17,000 | 17,000 | 17,000 | 17,000 |
Herbicides | 6,000 | 6,000 | 6,000 | 6,000 | 6,000 | 6,000 | 6,000 |
Planting materials/ha | |||||||
Plantain sucker | 83,350 | - | - | 83,350 | 83,350 | 83,350 | 83,350 |
Cassava cutting | - | 15,000 | 15,000 | 12,510 | 12,510 | 12,510 | 12,510 |
Insecticide | 5,000 | 5,000 | 5,000 | 5,000 | 5,000 | 5,000 | 5000 |
Planting/ha | |||||||
Labour hired | 40,000 | 50,000 | 50,000 | 90,000 | 90,000 | 90,000 | 90,000 |
Weeding (herbicide) | 12,000 | 12,000 | 12,000 | 12,000 | 12,000 | 12,000 | 12,000 |
Miscellaneous | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 | 30,000 |
Total variable cost | 283,350 | 208,000 | 208,000 | 345,860 | 345,860 | 345,860 | 345,860 |
C. Fixed cost | |||||||
Land rent/ha | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 | 10,000 |
Depreciation | 2,700 | 2,700 | 2,700 | 2,700 | 2,700 | 2,700 | 2,700 |
Total fixed cost | 12,700 | 12,700 | 12,700 | 12,700 | 12,700 | 12,700 | 12,700 |
D. Total cost ₦ | 296,050 | 220,700 | 220,700 | 358,560 | 358,560 | 358,560 | 358,560 |
E. Gross margin ₦ | 594,150 | 579,200 | 523,200 | 879,140 | 666,540 | 692,840 | 578,840 |
F. Net farm income | 581,450 | 566,500 | 510,500 | 866,440 | 653,840 | 680,140 | 566,140 |
G Returns/₦ invested | 2.964 | 3.567 | 3.313 | 3.416 | 2.823 | 2.897 | 2.579 |
The result of the pre-planting soil analysis carried out on the soils showed that the soil in the experimental site was a sandy clay loam according to soil textural triangle. The low nutrient concentration at pre-planting may be as a result of the opening of the fallowed land which involved uprooting of trees and shrubs, which might have exposed the nutrients to leaching and volatilization. The pH of the soil decreased from the pre-planting pH of 6.54 (slightly acidic) to a pH less than five (< 5) which were 4.62, 4.63, 4.63 (low) for the sole crops and 4.46, 4.47, 4.00, 4.20 (very low) for the intercropped treatment combinations. There was an increase in nutrient concentration when post planting soil analysis was carried out. The increase in nitrogen concentration, organic matter, available phosphorus, calcium, magnesium, potassium, and sodium in the soil may be as a result of the decomposition of the organic materials (leaves from trees, broad leaf weeds, succulent shrubs left in the soil when the land was opened, as well as the protection of the soil from exposure to sunlight and direct impact of rain fall by the cultivated crops.
The effects of the dry spell encountered during the dry season from November 2015 to March 2016 resulted in the decline in pseudo stem girth of the plantain which resulted in the lodging of poorly developed stands, as well as decline in the number of functional leaves to an average of (2.5) leaves per stand, this reduction in the number of leaves may be a kind of survival strategy for the plant
The time of planting cassava into plantain in an intercrop is very important. The reduced height of the cassava intercropped at 4 weeks was a sign that plantains are quick to establish their roots. This was supported by Lavigne
But the cassava varieties intercropped at 4 weeks did not experience any decline in its number of leaves up to 24 weeks after planting, this might be as a result of the competition they experienced from the day they were planted which resulted in their slow growth. At 24 weeks after planting, the cassava intercropped at 4 weeks showed significantly lesser number of leaves compared to the sole planted and those intercropped at the same time. This is an indication that late intercropping may have effect on cassava number of leaves. The stem girth for TMS98/0581 intercropped at 4 weeks was consistently less compared to other treatment combinations; this may be as a result of competition for light. The yield obtained from the cassava showed that the yield of (TME419) intercropped with plantain at the same time was of no significant difference (P<0.05) with TME419 and TMS98/0581 planted sole in terms of tuber length, tuber girth, tuber weight, root biomass, and shoot biomass. TME419 was significant (P<0.05) in terms of performance compared to TMS98/0581 intercropped regardless of planting time and variety. The TME419 and TMS98/0581 intercropped at 4 weeks, showed a significantly low yield except in the case of tuber weight and shoot biomass for TME419, and shoot biomass for TMS98/0581 which did not differ significantly (P<0.05) from the sole planted and those intercropped at the same time. TMS98/0581 intercropped at the same time had a lesser root yield which was significantly different (P<0.05) from the sole crop, and TME419 planted at the same time. Therefore, with the result of the yield obtained from each cassava treatments, TME419 had the highest yield which may be as a result of its less competition for light due to the plant architecture, which further buttress the point made by Reddy and Willey
The cost benefit analysis revealed that intercropping plantain using TME419 at the same time had more economic advantage compared to plantain sole, TMS98/0581 intercropped at the same time and at 4 weeks had lesser return per ₦1 invested compared to TME419 intercropped at the same time and at 4 weeks. The result further revealed that planting TME419 and TMS98/0581 sole had higher return on investment compared to plantain sole, but in the long run plantain will be most profitable, because there would be little cost on maintenance before the next harvest compared to the initial cost of production.
The aim of this experiment to find out the cassava variety which is compatible with plantain for intercropping purpose, and the appropriate time to introduce such into the alley of plantain, as well as the effects of the intercrop on the soil nutrients. The following conclusions were reached;
TME 419 is compatible for intercrop with plantain, and the most compatible time to intercrop should be at the same time. The poor branching architecture of TME419 may explain its compatibility with plantain,
Cassava can be used as a companion crop in the first year of establishing a plantain plantation so as to maximize profit,
The result of the post planting soil analysis revealed that there was an increase in soil nutrients concentration and soil pH. This may be as a result the decomposed soil organic materials,
In the intercrop, planting cassava into plantain alley at 4 weeks may increase the dry matter yield of cassava, but may not be of advantage because of the low tuber yield,
Sole crop of plantain produced significantly higher yields compared with the intercropped, regardless of time of planting, plantain yields among the intercropped treatments did not differ significantly,
The land equivalent ratio (LER) and area time equivalent ratio (ATER) of the intercrop combinations were greater than one (>1), an indication that additional land will be required to obtain the same yield in sole crop as obtained in intercrop.
It is recommended that further research should be carried out in the same location by planting at different times of the year so as to be able to recommend most suitable of the year for sowing cassava/plantain mixtures, and a short duration leguminous cover crop can be introduced to the intercrop, this can be an additional and quick source of income as well as suppression of weeds before the cassava-plantain mixture forms complete canopy cover