Maize is an annual crop with height ranging from 0.40 metres to five metres. It has shallow and fibrous roots that grow to a maximum depth of 0.50 metres with adventitious roots which form at the nodes near the base of the stem. It is woody, and filled with sweet pith, and with nodes and internodes that can commonly be around 0.20 metres each. The leaves are found alternating on each side of the stem. Maize leaves are very large (up to 10 cm wide and 1 m long) and sheath-like with a flat, extended blade in the shape of a strip with parallel veins. Maize (Zea mays L.) is the second most important food crop after cassava (Manihot esculenta Crantz) in Africa, and is grown in a wide range of environments. It is often cultivated in a favourable climatic zone with an average annual rainfall of between 760 – 1520 mm per annum and strong sunlight, which will help to reduce parasitism. Maize requires a temperature of between 10 and 19 °C, and should not be cultivated at an altitude above 1800 m.
- Different types of maize therefore exist depending on the purpose of planting which include:
- Dent maize: The grain contains soft starch granules which are less densely packed than in other types of maize. This results in the shrinkage of the starch within the outer layer of the grain. The grain is thus characterized by an indentation at the distal end. Dent maize has either a yellow or white grain. The most popular varieties of Dent Maize are TZB (FARZ – 34), TZB (FARZ -27 and 096EP6) (FARZ – 23).
- Floury maize: The floury maize seed (or grain) consists largely of soft starch which is surrounded by the corneous layer under the pericarp. This maize is grown mainly in the most southerly parts of Nigeria. Some varieties are-. Lagos White, Bende Local, Ikom White and Akwete Local, all of which are used in the breeding programmes in Nigeria.
- Flint maize: This variety has very little soft starch in its grain (unlike Dent corn). Some varieties of this maize are NS-1, Diacol-V-153 and Samaru 123.
- Popcorn: This is an extreme form of Flint maize. It has small kernels (grains) on a small ear. It is fried in oil to make. The starch granules are enclosed in a very tough and elastic membrane. When heated this tough membrane resists steam pressure until it explodes.
- Sweet maize-. This is valued for its sweet flavour. This variety has a much higher sugar content than all the other types, and it is usually boiled or canned.
(2)Selection of good variety and quality seeds of maize for planting is very crucial and should be carefully done as this determines the success of a maize farm: The choice of variety of maize will depend on the cultivation area, the climate, soil type, local technology to be used and the end-use of maize output. Varieties that grow very high and have a short cycle are best suited to high altitude regions while dwarf varieties are suitable for all agro-climatic conditions. On the other hands, varieties with a medium-length cycle are suitable for medium-height altitudes. In addition, good quality seed from agronomical research centres or best cobs from the previous harvest. It is important to know that the best kernels are in the middle of the cob. The kernels should be healthy and come from a pure and improved variety. Local varieties which give good yields can also be considered for selection only from the largest and healthiest cobs. Moreover, varieties of maize should be selected according to intended market either as animal feed, human consumption or industrial used. For example, large-kernel varieties are suitable for human consumption while small-kernel varieties are good for animal feed. More importantly, seeds with germination capacity of at least 90 percent are mostly preferable for planting.
(3) What kinds of soil is best fit for maize production?
Maize thrives well in soil that is deep, loose fresh, fairly light, well drained, fertile and rich in organic matter. The texture of the soil should be intermediate such as sandy, sandy-loam to sandy-clay loam. The surface of the soil (plot of land) should be flat or with a gentle slope of no more than 12 percent so as to facilitate low set-up costs.
(4) What are the farm implement required for maize production?
- Hoes: It is used for weeding, and to break up lumps of earth when preparing the seedbeds.
- Machetes: This is useful for clearing the undergrowth and planting of seeds
- Weighing balance: It can be used to weigh manure, fertilizers and agrochemicals such as herbicides, pesticides and insecticides.
- Farm buckets: It is used to spread manure.
- Lines (cords): They are useful for taking measurements or marking the spacing when planting.
(5) What should be done before planting?
- It is advisable to cut down any undergrowth trees or branches so as to provide more light needed by the maize plants to produce higher yields
- Land clearing and preparation should be done earlier to facilitate working conditions
- Seedbeds may be needed to facilitate seed germinations
(6) Things to consider while planting maize
There are three major considerations to be taken into account:
- When to plant
- Depth of planting
- Plant population
When to plant: Planting is generally recommended to be done at the onset of rain but since maize. In southern part of Nigeria where it can be planted twice a year, the first season rains normally start in March and end in June, while the second rains start around mid-August to December which is called dry planting. Dry planting is advantageous because it the moisture content of the maize is low and its dry faster and also insect infestation is reduced where it occurs.
Depth of planting: Planting depth depends on the moisture level of the soil where depth for 2-3 cm is adequate for moist soil and 5-10 cm is recommended for dry planting. Deep seed placement under dry planting is recommended so that seed germinate only after adequate rains have fallen. However the depth of planting should be uniform to allow uniform plant growth.
Plant population: The recommended spacing for maize is 75 cm between rows and 30 cm between seed holes when planting one seed per hole while a spacing of 75 cm between rows and 60 cm between seed holes in a row allowing 2 seeds per hole. With this spacing the amount of seed required will be between 20 and 25 kg per hectare. When the population density of the plants is higher than the optimum, it will lead to competition among the maize plants resulting into slender plants and hence it gives low yield. However, Lower population density of the maize plants will result into low yields due to reduced number of ears per unit area.
(7) What are the methods of planting maize?
Planting of maize is done in two ways:
- Hand planting: Hand planting is the most commonly used method among maize farmers which is accomplished by use of machetes. This method can produce excellent results because it gives a proper and uniform plant stand.
- Mechanical planting: This type of planting is done by use of farm machineries such as tractor and planter. It has very fast; allows to plant a large range of land size and gives excellent results under good supervision.
Hoopen M.E and Maïga A. (2012): Maize production and processing. Pro-Agro collection. pp 9-19
Oluwaranti A., Fakorede M.A.B, Menkir A. and Badu-Apraku B. (2015): Climatic conditions requirements of maize germplasm for flowering in the rainforest Agro-ecology of Nigeria. Journal of Plant Breeding and Crop Science. Vol 7 (6) pp 170-176
Tenebe V.A. and Petu-Ibikunle. A.M: Arable crop production. School of Science and Technology. National Open University. www.nou.edu.ng/uploads