Cladosporium speckle is caused by Cladosporium musae. The disease starts as small brownish spots similar to pencil specks

three to four weeks after leaf unfurling.The specks enlarge and the leaves become greenish black. As the leaf ages,

the spots turn orange-yellow then brown and finally necrotic,necrosis starts from the margin of old leaves.

Highland bananas have beer 1 found to succum to  another  wilt syndrome (Matooke wilt) in Western Uganda highlands at altitudes above 1330 metres above sea level (m.a.s.1.).This wilt has since been erroneously diagonised as fusarium wilt.The disease has not been observed at lower elevations below 1330 (m.a.s.1.)

even in western Uganda,Matooke wilt is virtually limited to areas around homesteads, garbage dumping sites and animal kraals.

Matooke wilt does not spread farther than 35 metres off thehomesteads. It causes yield losses of up to 78% in bunch
weight of Enyeru cultivars. Such losses are usually morsevere closer to the homesteads where farmers expect higher
yields because of higher organic matter content.

suckers from seriously infected mats when transplanted from these sites to non infested soils out grow the disease and produce

healthy branches and healthy suckers.casual agent of this wilt syndrome is not yet known but investigation is in process by research.

The severity of this disease can be minimized by applying sanitary measures of removing infected plants and applying
properly decomposed household refuse on fields.

This is transmitted by several aphid species and may occur inone form or the other where bananas are grown.

The diseaseis rare and may not be serious.

The most characteristic symptom is the loss of leaf colour in pathes, rendering leaves variegated in appearance. The
variegations may be roughly parallel to the lateral veins, but not always, giving leaves a striped appearance. As the disease

progresses, leaves emerge, having perhaps one or both sides of the lamina not fully developed so that the leaf margin instead
of being smoothly curved is irregularly wavy, often with blotches of necrotic tissue and the lamina is reduced in width.

Sometimes rotten areas are found throughout the leaf sheaths and the pseudostem.

In cooler areas, rotting of the heart leaf may develop to such an extent that a soft black rot extends right down to the corm
(the 'heart rot' condition). The older leaves show black or purple streaks and may shed.

Fruits on infected plants may not show any symptoms or maybe stunted with chlorotic streaks or may show necrosis

Planting matem1 should be checked so as not to introduce the disease to a new plantation. Plants of the tomato and cucumber
families, maize, Panicum sp. and Digitalia sp. are known tocarry the virus. Intercropping bananas with such plants should be avoided. Non-host cover crops can be planted to suppress:

The infected plants must be destroyed by digging them up Eradicate all the suckers in the mat even if they appear healthy
Where possible the-vegetation surrounding the diseased site can be destroyed to kill aphids using malathion or another suitable

Typically yellowing and wilting of older leaves, as well as reduced fruit size and eventual rotting of the fruit.

In addition flowers can become blackened and shriveled, and the vascular tissue discolored. Exclusion of the disease where it is not present is the only effective means of control.

If an area does become infected all of the infected plants must be eliminated, which is why strong sanitation practices must be used to reduce the spread of disease.

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article thumbnailFarmers in the East African Highlands, centred on Uganda, depend on bananas as a staple food crop and a source of income. The harvest, however, is threatened by many pests and diseases that also...
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The vast majority of the bananas currently grown and consumed were not conventionally bred but are selections made over probably thousands of years from naturally occurring hybrids. Cultivated bananas are very nearly sterile and as a consequence are not propagated from seed but rather through vegetative propagation, primarily suckers as well as more recently micropropagated or tissue cultured bananas. These factors, very old selections, near sterility and vegetative propagation, mean that these bananas have not been genetically improved either for resistance or improved quality and are becoming increasing in affected by serious pests and diseases.

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