Cassava: Food Crop And Fuel Crop
If cassava were to be human, you would describe cassava as a very hardy, resilient, and a versatile person. However, as we all know, cassava is a plant. More specifically, we can describe the cassava plant as a shrub usually 2m to 2.5 m in height, with a short brittle stem and high pith content. Its edible root is dark-brownish in color, thick, fleshy and starchy and usually divides into several partially separate tubers, which grow to lengths of one metre or more. The two main species widely grown in Nigeria are the sweet and bitter cassava, Manihot utilessima and Manihot palmate respectively. The bitter cassava species, Manihot palmate, contains some poisonous hydrocyanic acid in its root. Thus, part of the processing of the bitter species of cassava would involve total removal of the acidic content in its root. Despite the comparatively recent origin of the crop, there are many varieties of the two species in cultivation throughout Nigeria. High yields, food qualities, disease-resistance quality are important considerations in the selection of varieties for cultivation.
Cassava thrives well in a well-drained, rich, friable, loamy soil .However, there is a reason cassava was described as a hardy and versatile person in the opening sentence of this article. This is because cassava is known to thrive in poor soils. This also explains its wide distribution across Nigeria due to its ability to thrive on most of the soil types found in Nigeria. Still, the South-South and the Southeast states of the country still have a large share of cassava cultivation. These states include Imo state, Anambra State, Cross-River State, Rivers State, Delta state, among others.
In addition, cassava thrives under varying climatic, especially rainfall conditions. Although an annual rainfall of 101cm-152 cm is considered ideal for optimum output, cassava can be cultivated in areas with as little as 51 cm a year.
Cassava plants can be propagated into new breed making use of the asexual propagation of stem cuttings. These stem cuttings are usually planted from March to September. Thus, we can deduce that the planting date of cassava is from March to September, which falls under the rainy season. A stem cutting of 25cm-30cm long is pushed into the ridge or heap tilted at an angle of 45 degree centigrade,2/3 of it buried with a spacing of 1 metre by 1 metre. Sprouting usually occurs 7 – 14 days later. It is advisable that weeding should be continually carried out regularly and around 250kg/ha of N.P.K fertilizer should be applied four to six weeks after planting.
While it grows, do expect that pests and diseases would likely attack the cassava. Arm up, take up your weapon and get ready to attack the variegated grasshopper whose adults and nymphs eat up the leaves and young stems of the plant. Arm up against the rodents which include bush rats, grass cutters, cane rats, e.t.c. Those rodents that dig up the alluvial soil on which our cassava plants thrive on .Those rodents that gnaws at nature’s treasure with their cursed canines. You control these pests and put them in their place by trapping, placing a wire fencing around your farm, or shooting them on sight with a gun .However, if issued in your country, do get a license for that gun. The last thing we would want is you bidding time napping in a police station while your cassava plants are exposed.
Relating to diseases, a farmer should keep his or her eyes on the deadly trio that can ride shod on ones cassava farm if care is not taken. We have the cassava mosaic disease. A virus transmitted by the piercing and sucking white flies causes this disease. The symptoms include vein clearing and distortion of the leaves. The cassava plants become dwarfish. The controls against cassava mosaic disease include uprooting and burning the poor and unfortunate infected plants. Next time, the farmer should take preventive measures by planting resistant varieties of cassava.
When you notice an angular, water-soaked area of discolored leaf tissue, blighting, wilting, reduction in yield, dear farmer, your cassava is not really just under the weather, but is actually infected with bad bacteria blight. As the name implies, bacteria is the cause of the blight. Since we all know that prevention is better than cure, it would be smart that a farmer should make the move of going for resistant variety of these plants. At the very start, do not just buy any stem cuttings. Ensure it is a stem cutting of a disease-resistant variety.
A fungus causes angular leaf spot. Symptoms include spores, which produce pale, brownish color on affected leaves. Spray with fungicide, uproot and burn infected plants and the use of resistant varieties should be employed.
The cassava is due for maturity between 8 – 15 months after planting, depending on varieties. The cassava farmer can harvest making use of cutlass. Alternatively, the technologically adept farmer can adopt the cassava puller. No matter the implement used for the harvesting, the most important is that the farmer should uproot the stem of the cassava plants gently so that there is no damage done whatsoever to the root.
The harvested cassava tuber can be processed into garri, foo foo, flour or even livestock feed. However, at this point of storage, a cassava farmer can expect an offer from the bio fuel merchants. The farmer should not scratch off his hair in confusion. It would interest us to know that the starchy content of cassava can be converted to ethanol, a form of bio fuel. Ethanol from the starchy content of cassava is known to possess a very high-energy content per acre. Thus, in the face of the unpredictable price of crude oil in the world market, it is economically viable to convert cassava ethanol, known as bio fuel and use to power up some bio fuel-compliant machines to do your work.
Barring any unforeseen circumstances, a farmer can harvest between 25-40 tonnes of cassava per hectare with effective irrigation and constant fertilizer application. It is very much highly possible that with the right technology in place, 200 litres of ethanol from a tonne of cassava, assuming the cassava to be used have at least 22% starch content. You can make the calculation and really know the economic value of that tonnes of cassava you just harvested. Now, we have people who would do differ on the practice of converting cassava to fuel. They fear an apocalyptic shortage of food, thus, leading to a large-scale hunger worldwide.
In the face of this familiar Food vs. Fuel debate, the question on most farmers’ mind as they uproot their matured cassava tubers could possibly be:
Should one sell off these cassava products to the food market?
Should one sell off these cassava tubers to the fuel market?