You will select the ripened fruits, preferably those that have fallen by themselves. You should not use fruits that have been plucked from the tree. You will then remove the pulp carefully and completely and wash the nuts thoroughly using sand and water. You will allow the nut to dry in the shade for one or two days if it is during the dry season or three to four days during the wet season.
in the sun.
3.1.1 Seed Germination
10 cm
17 cm
Seed germination should be done in a polythene bag which is thick, complete and strong, basket or perforated tray.
Figure 1
Seed Saw dust
Top soil
You should fill the container with rich top soil to a height of about 17 cm. Then you will put uncontaminated saw dust on top of the top soil to fill the next 10 cm.
You will now plant your seed in the centre of the polythene bag, making sure that it is well covered by the saw dust (see figure 1 above)
You will ensure that seeds are planted within two or three days after extraction. If you have been experiencing the problem of damping-off disease in the environment, then you should treat your seed with benlate by dusting the seeds completely or any other suitable recommended fungicide. After planting, you should water daily and keep in shady environment. For a polythene bad of about 15 cm diameter, you may plant 3 – 4 seeds.
Germination should start about 3 weeks after planting and it may continue for several weeks, there after. At about 12 months after germinatio, your seedlings are ready to be transplanted to the field or to be budded.
3.1.3 Budding
Where you intend to carry out budding, you should obtain bud wood from mature flowering trees, preferably during the month of June during raining season. You will need root stock of about 0.5 cm diameter or pencil size at about15 cm from the soil surface. You will carry out your budding while the seedlings are still in the polythene bag in the nursery. You should transplant your budded seedlings to the field 9 – 12 months after budding.
3.1.4 Fueld Establishment
Your seedling will be ready to be transplanted to the permanent field site about 9 to 12 months after germination or 9 to 12 months after budding.
You will transplant the seedling into the pre-dug holes of 1m x 1m x 1m at least two weeks before trasplanting. The holes would have been filled with top soil first, then manure and 15: 15: 15 compound fertilizer, thoroughly mixed. Your field spacing should be 7m x 7m. Your transplanting should be done in he month of June, during the raining srason and you should transplant with the ball of earth around the roots well intact.
3.1.5 Field Management/Maintenance
You should eetablish a cover crop to protect the soil, but this will have to be faced out as the trees form their canopies. If you so choose, you may inter crop your trees between rows with other crops such as cassava for the first few years.
You should water or irrigate your seedling during the first dry season after transplanting into the field, because the deedling may not have develop a sufficiently deep root system. The first formed flowers by the seedlings in the first few years should be removed to allow for very strong vegetative development to be supported by applying manure. You should use nitrogenous and potassium fertilizers as well. You should weed your seedlings regularly to allow a maximum yield from your inter-crop and later your trees.
3.1.6 Harvesting
You should harvest your Irvingia when the fruit are mature. The stage M of harvesting depends upon the purpose for which the fruits will be used. If you are transplanting the fruits to outside market from souce of production, you will harvest when mature and green.
For fresh market, you allow the fruits to be fully ripe and fall from the tree, and you will go round to pick once or twice daily. If your fruits will be used as stones for germination, you should use fruits that are fully ripe and have fallen from the tree on their own. For any purpose at all, you should avoid havesting damaged and bruised fruits to avoid diseases.
3.1.7 Uses
Irvingia fruits are delicacies because they are not commonly available. They are eaten as fresh fruits in the south western and eastern zone of Nigeria. They are particularly value as fruits and desserts in Ibadan land. The fresh fruits are getting
popularized in the northern zones of nigeria by the southerners living in the north. The fruits are shipped from the south.
Delayed ripening is being encouraged and further work is contiuing by researchers to ensure availability of Irvingia fruits all round the year. The most popular use of Irvingia all over the country is the draw soup ingredients known as Ogbono soup. It goes solely or a mixture with “egusi” and/or other vegetables to eat pounded yam, eba, apu. Amala and semovita. Irvingia has a potentialas future juice drink.
3.1.8 Chemical Composition
Irvingia is a fruit tree for the future. Little work has been done by food
nutritionists in the area of chemical nutrition. You may wish to know that the chemical composition would be similar to that of mango. The fruit is rich in vitamin C and same level of proteins. The seed is rich in protein, carbohydrate and traces of vitamins. Irvingia is said to be of medicinal value.
3.1.9 Pests and Diseases
There are not many known pests and diseases of Irvingia. Tree is generally free from pest attcks and disease infections. Hiwever, in some areas you may experience some fungal diseases such as pamping off. This is effectively controlled by dusting seeds with banlate or any other suitable fungicide before planting.
Exercise 15.1 SMA
Irvingia is not a well known tree crop popularly grown in Nigeria. How do you obtain seeds and extract same for propagation?
- You will select ripened fruits, preferably those that have fallen by themselves.
- You should not use fruits that have been plucked from the trees.
- You will remove the pulp carefully and completely and wash the nut thorougly using sand and water.
- You should let be nut dry in the shade for one or two days.
- Prolonged drying formore than a week will resulting decrease seed viability.
- You sould avoid drying in the sun.