Cassava (Manihot esculenta), is one of the most popular and widely consumed food crops in Nigeria which is also known as a woody perennial plant . Cassava is native to South America introduced to Africa by the Portuguese in the year 1958 through the Congo basin, has since gained acceptance in Africa and this plays an important role in agriculture among developing countries, especially in sub-Saharan Africa, because it does well on poor soils with low rainfall but it is grown throughout the tropics and subtropics . Cassava can be grown in challenging conditions (e.g., dry soils with low fertility) and it can be harvested when needed (i.e. not only at the end of the growing season), providing a reserve of food in times of war and famine . Average cassava yields (e.g., root yields of 11.6 t/ha worldwide, in the 5 years from 2011 to 2015 ) are much lower than potential cassava yields, but better farming practices could help to close these yield gaps (e.g., root yields of 60 t/ha have been reported in parts of Africa). The plant requires a rich, light, well-drained, unshaded soil. When sown late in the season, it behaves as a biennial. About three months after sowing, the plant’s outer leaves are tied together or are covered, to exclude light.
Land Preparation For Planting Cassava
When establishing a new cassava production , certain actions need to be implemented to ensure the long term success and high yield of the plantation.The purpose of land preparation is to provide the necessary soil conditions which will enhance the successful establishment of the production and improve yield of crop over years to come. Planning forms part of the initial preparation and will help to limiting unnecessary stoppages during the implementation phase of cassava production.
Critical factors to consider during this planning exercise are summarised as follows:
– Time schedule.
– Field selection;
– site preparation
– Availability and quality of water;
– Mechanical actions to be implemented;
– Chemical needs for pre-plant soil improvement;
Cassava Planting starts in April and can be extended to October.A total herbicide – Round up (a glyphosate) should be applied to the land where you want to plant your cassava at the rate of 4–5 l/ha 10 days before land preparation. For cost effectiveness and optimum plant population of the cassava .
The first thing is selecting area for cassava production After choosing a suitable site for cultivation, clear the vegetation in the area. This is done to let in more sunlight to the ground and to remove weeds and undergrowth which might otherwise compete with economic plants. Cassava requires a sandy loam soil rich in organic matter; this soil is a well-drained soil that does not allow waterlogging situation, it allows free flow of water and air. The presence of the organic matter in the soil helps to build the soil structure to enable it retains moisture. Also, it supplies plant nutrient for the growth of the cassava plant.
The mechanical or initial soil preparation concerns mainly the preparation of a field for further detailed preparation such as irrigation system installation, stumping, levelling, etc. Actions, if applicable to the area, include:
(i) debushing/bush clearing;
(ii) removal of stones and rocks;
(iii) ripping; and
(iv) levelling of the soil.
AVAILABILITY AND QUALITY OF WATER
Cassava can grow in areas with 400mm of average annual rainfall and higher yield can be obtained with higher level of water supply.
Unlike most other food crops, cassava does not have a critical period during which adequate soil moisture is essential for flowering and seed production. It also has several defence mechanisms that help it to conserve water, and its roots can grow to great depths to access subsoil moisture reserves. As a result, cassava can withstand relatively prolonged periods of drought. However, the crop is very sensitive to soil water deficit during the first three months after planting. Stakes will only sprout and grow well when the temperature is above 15°C and the soil moisture content is at least 30 percent of field capacity.
MECHANICAL ACTIONS TO BE IMPLEMENTED
Cassava farming depends on soil type and drainage, the field may be prepared as mounds, ridges, flat-tilled, or zero-tilled. Where mechanisation is available, the land is ploughed and harrow to a depth of 25cm. However, planting on flat soil, requires cuttings directly into the land. The most common implements use in land preparation is the plough and the harrow. The Plough is used to turn and mix the soil, this exposes the lower region of the soil thereby disrupting the pests and exposing them to ssssssssunfavorable condition. This will greatly help to reduce their population or even eradicate them completely, while the harrow is used to smoothen the ploughed land, it helps to remove weeds and other pests on the land before planting is done. Harrowing is usually done 2-3weeks after ploughing is done as it helps to provide nutrients to the soil and also help loosen the soil to ensure good root and tuber formation of the cassava plant.
Chemical Needs For Pre-Plant Soil Improvement
In order to checkmate soil pH, certain applications could be combined with the initial actions of soil preparation. Due to the long waiting period, planting to first production.
Nitrogen plays a major role in plant life processes such as photosynthesis, vegetative growth and the maintenance of genetic identity. This ensures high yield at the end of the season.Nitrogen is freely available to plants within the pH range of 5.5 to 8.5. When the soil pH is below 5.5 or above 8.5, the availability decreases to the extent that plants are not able to take up any nitrogen from the soil profile.
Phosphorus also plays a role in processes such as photosynthesis, respiration, vegetative growth, reproduction and maintenance of the genetic identity. It is also associated with cell division, root development and flowering. Phosphorus is freely available to plants within the pH range of 6.0 to 8.0 and above 8.5. When the soil pH is below 5.0, phosphorus is, for all purposes, not available to plants.
Potassium is found in cell sap and plays a role in the transport of nitrogen in the plant and the promotion of photosynthesis. This nutrient helps to strengthen fibre and has an influence on the opening and closing of the stomata. Potassium is also associated with resistance to drought, cold and the improvement of fruit quality. Potassium is freely available to plants within the pH range of 5.5 to 7.5 and above 8.5. When the soil pH is below 5.0, potassium, is for all purposes, not available to plants.
Major positive attributes of cassava is that it does not have a specific harvesting period. Roots may be harvested any time between six months and two years after planting. During periods of food shortage, they can be harvested whenever needed, often one plant at a time. For human consumption, harvesting usually takes place at about 8 to 10 months.land can be used again after harvesting.