Ways to get high yields from cassava

Cassava is an important staple food crop for many people in Uganda especially West Nile, Northern and Eastern Uganda.
It is also widely grown in other parts of the country such as Kasese as a famine reserve crop. It has high yielding capability, easy to grow and performs well even in marginal areas.
Cassava provides a good source of alcohol and industrial starch apart from people using it for food consumption either in flour form or eaten fresh and boiled.

Gardening
To achieve success, there are several agronomic practices a farmer must adopt.
These practices enhance the soil conditions and provide a favourable condition for the growth and development of the cassava plant from the point of planting to harvesting, thus, bringing about high yield.
Dr Titus Alicai, head of root crops department at the National Crop Resources Research Institute (NaCRRI), Namulonge explains the process and steps for farmers to follow ahead of planting.
Soil
Cassava can be grown on a wide range of soil but best on deep, free draining soils with reasonable fertility levels. Shallow soils which may restrict tuber expansion should be avoided. Waterlogged soils and swampy areas are not good for cassava production.

Rainfall
The crop is highly drought resistant and grown in many parts where rainfall is low and unreliable. And it grows at all altitudes but best on low to medium altitudes but farmers may obtain low yields on very low altitudes.

Weeding
Keep the crop weeded in the second month after planting and intercropping also helps to suppress weeds.
Farmers are advised to plant when the soil is moist meaning they should target first and second season rains and once the stalk germinates, the plant will be able to grow.
Planting during dry season will lead to failure of the seeds to germinate coupled with destruction caused by pests such as termites.

Pests and diseases
Most times insect pests are not a threat to cassava production but still need attention.
The most notable ones include Cassava mealy bug which attacks mainly the growing points of the plant causing stunting, leaf and deformation. Severe damage leads to tuber quality deterioration.
Another one is Cassava green mite a sucking pest which leads to reduced growth, scorching of leaves, tiny leaf production, leaf fall and eventually a plant without leaves. This causes great yield reduction or loss and the worse is the whitefly which spreads CMV and CBSV.
The best control method is use clean and tolerant varieties like Nase 14 and 19 plus biological control of spraying the plants with recommended chemicals
Cassava Brown Streak Virus is a deadly viral disease causing brown streaks on green stems and rooting of the tuber and can cause up to 100% loss.

Harvesting and post-harvest handling
Cassava takes eight or more months to mature depending on the variety. Yields also vary depending on variety and soil type with average yields of 10 – 30 tonnes per acre.
Cassava harvesting may be done one by one or by uprooting the whole plant. A stick or hoe may be used to remove the tubers.
It cannot be stored fresh for a long time therefore sliced and dried in the sun is the best way and it can be kept for long periods of time in a dry bag in a place such as granary or other food stores.
The dry cassava may also be pounded into flour which can be stored for a long period of time in a dry place.

Farmers
Dr Alicai says “since the crop is tolerant in drought prone areas, farmers in Kasese District who abandoned cassava growing can still go ahead to grow the plant. They have to make sure they carry out planting when there is moisture in the soil which is a key factor for growth of the plant.”
In a recent interview with the Kasese District principal agriculture officer Julius Rukara who doubles as a farmer about the future of cassava growing he noted that most people in the district feed on cassava as their staple food but the flour is imported from other cassava growing regions.
He noted that a number of farmers stopped growing cassava but the district is revamping it by demonstrating planting of varieties such as Nase14 and 19 for onward distribution.

Varieties
Many popular varieties have been wiped out by the Cassava Mosaic Disease (CMD) and Cassava Mosaic Virus (CMBD). New varieties with tolerance to CMD and CBSD have been released and others are still being developed. The new varieties are NASE series with farmer preferred varieties being Nae14 and 19.
It is important to ensure the planting material is clean free from pest and disease infestation and the source of material must be a reliable one like research institutes and farmers who growing cassava for seed multiplication.

Land preparation
The cassava seedbed requires deep cultivation of the land to a depth of three metres. A rough seedbed is preferred. Ridges or mounds are used in other areas and it encourages tuber development.
Planting
Planting is done by use of cuttings and the parts of the stem should be from a mature plant, especially the middle part.
Cuttings may be buried in a horizontal position of two by 10 centimetres deep or buried half way into the soil.
In pure stands without intercropping, a spacing of 1.5 metres by 0.9 metres is recommended. When intercropped, interplant with a cover crop of beans or groundnuts at a spacing of 50 by 20 centimetres. This combination gives maximum yields of both cassava and bean or groundnuts.