Archive for the ‘post harvest handling’ Category

Sugar Cane (Saccharum Officinarum)

Sugar cane is a perennial grass, which under favorable conditions grows to a height of 2.5- 6m depending on the variety. It has a well developing fibrous roots found mainly in the top 25- 30 cm of the soil and which may spread outward to 2m. The stem, sometime known as canes or culms usually grows erect but are procumbent in some varieties.

Sugar cane is un-branched except for the tillers and consists of a series of nodes and internodes. The crop is mainly grown for sugar and this sugar may be extracted from the stems and used for sweetening a wide range of foods and drinks. It may also be used to making sweets, chocolates, spirits and sweetening livestock feeds. The crop requires a minimum annual rain fall of 1,500mm of which at least 70% should fall evenly during the growing period. Artificial irrigation is necessary when this amount of rainfall is not available, if maximum yields are to be realized.

Sugar cane grows on wide range of soils although it prefers heavy fertile and well drained soils. The PH required is not very critical as the crop may grow quite well in soils with PH of 4.2- 8.5. The growing season should be warm with mean day temperature of 28- 30 centigrade while temperature below 20 centigrade retards growth and those above 35 centigrade reduces photosynthetic rate.

Photorespiration increases with temperature can appear wilted irrespective of water supply when temperatures approaches 35 centigrade and growth is curtailed. Low temperatures are the effective means of ripening cane, counteracting adverse factors such as excessive moisture or nitrogen.

Land preparation and planting

Land preparation involves; clearing the bushes, removing stumps, building terraces or ridges to prevent soil erosion, grading slope grounds in preparation for irrigation by gravity, demolishing ant hills, ploughing and making furrows. Three eyed setts are planted in furrows at the depth of 20-30cm and 1.5m between the rows and cover with 2.5 7.5 cm of soil.

The planting material is obtained either from the harvested cane (the white tip) or from seed nurseries. The setts are planted in rows and they are placed end to end with a slight overlap. Double planting of poor tillering varieties can be well worth while with the yield benefits extending with ratoon crops. A seed bed density of 2,500-3,000 setts per ha or 6 to 7 tons of sugar cane per ha. Sugar cane can be planted almost any time of the year though it is best to avoid dry periods (December to February and July to August) to uplands as the plants are then delayed to germination and early growth.

Weeding

Weeding should be done soon after all the setts have germinated and this should be done 5 to 6 time for a better growth of the plant.

Manure and fertilizers

Plant is effective to sugar cane and it should be applied before the boom period (6 months). Filter mud is a useful by-product of the factory containing phosphorus and nitrogen so it is important to put it back to the field.

Fertilizers

Sugar cane responds well to fertilizer application and it has specific demands on phosphorus, nitrogen and potassium.

Maturity

The crop will mature at 15 to 24 moths depending on the varieties and season

Harvesting

The determination of the maturity of a field of cane is one of the most important aspects in managing the plantation. After the boom period of growth, some of the stems change from the vegetative to reproductive state and produce reproductive inflorescence called arrows or tassels. Appearance of the tassels at times can be deceptive as to the level of sucrose accumulated in the stems.

Where irrigation is practiced ripening is induced by withholding water several weeks prior to harvest. A more precise way of determining maturity is by using a hand refract meter which reads Brix number and for a mature cane the Brix should be 20%. Harvesting is done by hand using knives and specialized machetes and it is important that the field id cut clean as any short left in the stool gain advantage over those subsequently produced from the underground rhizomes, with  results that the following crop becomes very un-even

The number of ratoon that are economical to the harvest from the field before replanting depends on the characteristics of the individual fields, the variety of the cane and the method of cultivation used.

Pests

The following pest have been of concern in Uganda

Stem borer (sesamia vuleria.stoll). The attack commences near the apex of the short; the caterpillar boring in the softest tissue and then down the stem mainly in young canes. The infected plants have appearance of dead hearts within withered innermost terminal leaves.

Prevention

Prevent the pest by weeding in the garden regularly and treating the planting material in warm water. Control the pest by cutting of the dead hearts, and removal of borers successfully controls the outbreak. Allow atachinid fly in the as it is parasite on the caterpillar.

Eldana borer (Eldana saccharine)

Eldana borer causes serious damage in some parts of Africa to maize and sugar cane, the larva feeds on the outside of the stalk around the node after which it enters the stalk feeding the rest of its life inside the stalk.

Prevention is by clearing the papyrus around the garden as it is the alternative host and field hygiene. Control is by cultural methods, using hot water treating the seed cane.

Aphids (Rhopalatosiphum maidis fitch)

This is important because it is a victor of mosaic disease, and the danger caused directly by the insect is negligible. Prevention is by the garden free of weeds and all around the garden. Control by spraying a mixture of garlic and marigold leaves to repel the insects.

White scale

White scale insect stays on the nodes of the cane and sucks the juice reducing the quality of the juice and decreasing yield. The leave tend to dry and growth is suppressed and the plant may die altogether. Prevention is by weeding in the garden regularly and removal of the dry leaves of the cane. Control is by burning of the trash killing the larva and adults.

Termites

Termites cause serious damage to the crop during germination and maturity time. The insect cut down the growing plants causing death. Prevention is by destroying the ant hills around and in the field. Control is by applying Neem tree crushed leaves together with dry wood ash on the plant roots.

Diseases

Mosaic disease

The causal agent for this disease is the sugar cane mosaic virus (SCMV); the main symptoms are small irregular, elongated non-necrotic spots, yellowish green or dark green on a light background which appears on young leaves when in shade and causing plant stunting. It is transmitted by several aphids and through contaminated setts, and it causes a loss of tonnages and the extent of this loss depend on the varieties. Prevention is by avoiding the aphids in garden and keeping the garden free of weeds.

Red stripe disease

This disease appears mainly on young canes in the form of narrow continuous dark red to reddish brown stripes running longitudinally along the leaves from the base upwards, and the causal agent is the bacterium phytomonas rubrilineans. The tissue between the stripes is often pale green to yellow in colour and infected plants are easily sported in the field.

There are many other sugar cane diseases like smut, leaf spot disease, ratoon disease, root disease and top rot.

Planting Garlic as a Pest Control In your Garden

Garlic is one of the strongest pest control methods in gardens. While using it, plant it around areas where pests are a problem Most insects are repelled by the smell.

However, even the beneficial insects may be repelled by the garlic. This means that care must be taken while planting it so as not to loose the beneficial insects.

To control moles, Use one whole or crushed garlic and place directly into their tunnels. The odor of garlic is very strong to their sensitive nose, and this will encourage them abandon the area. Garlic plants also work as a great deterrent So planting garlic as a companion plant is helpful to eliminate a mole or rats.

Using garlic water for plants can also work as a tonic that seeps into the soil and disrupts the harmful insects that usuallyhide  there. moles  will avoid digging in the dirt that has been treated with garlic water.

Post Harvet Handling

A farmer, Mukose Mudodi from Mayuge district planted 2 acres of maize. When ripe for harvest, he took his whole family of five to get the crop from the garden. That evening, and for the next three days, his wife sold the cobs either fresh or boiled at the market every evening. However, by the fourth day, the cobs were going bad already. He then decided to sun dry and mill them to get flour. Imagine the quality of flour that resulted? Also, imagine the degree of palatability to humans?

This is a common trend among farmers in Uganda. They are oblivious of the fact that as soon as a crop is removed from the ground, or separated from its parent plant, it begins to deteriorate; thereby calling for immediate post harvest handling.

In agriculture, postharvest handling is that stage of crop production immediately following harvest. It includes cooling, cleaning, sorting, processing and packing. Post-harvest treatment largely determines final quality, whether a crop is sold for fresh consumption, used as an ingredient in a processed food product or sold in a processed form. Post-harvest handling is one of the major determinants of the final quality. This is what farmers’ do not do often resulting in rot of their crops and/or price wars leading to lower prices as compared to cost of production.

Many farmers often do not take to this stage of farming because either they do not know how to or financial challenges crop in. Some of them are not even aware of the value added and especially in relation to cost. All Mukose Mudodi had to do was to sell his cobs fresh for the first day. After that, probably sun-dry them and obtain flour for sell. That way, he would be more in control of how much he sells his milled maize. In a milled form, he can store it till the bumper sells have decreased and the prices have gone higher.

Another issue of concern here is: does he have the money to mill it? Or the mill to do it himself? Does he have packaging materials? Poor post handling procedures for the maize crop for instance can lead to development of aflatoxins. These when consumed by humans can lead to stomach upsets and even death especially when taken in huge amounts.

To process or not to is a decision a farmer has to make even before planting the crop. That way, he/she will be more prepared and hence less losses