{"id":6130,"date":"2017-04-05T14:16:42","date_gmt":"2017-04-05T11:16:42","guid":{"rendered":"http:\/\/graduatefarmer.co.ke\/?p=6130"},"modified":"2017-04-05T14:16:42","modified_gmt":"2017-04-05T11:16:42","slug":"new-pest-fall-army-worm-moth-on-cereals-and-pasture-in-kenya","status":"publish","type":"post","link":"https:\/\/graduatefarmer.co.ke\/?p=6130","title":{"rendered":"New Pest (Fall Army Worm Moth) on Cereals and Pasture in Kenya"},"content":{"rendered":"

Fall Army Worm Moth; is a migratory pest native to North and South America. This pest occurs in large numbers and its caterpillars cause severe damage to more than 80 plant species especially cereal crops such as: maize and rice.<\/p><\/blockquote>\n

Government Efforts to Manage the Pest<\/strong><\/h4>\n

The Ministry of Agriculture, Livestock and Fisheries constituted a multi- institutional technical team with experts drawn from public and private sector. The institutions represented include: KALRO, KEPHIS, CABI, PCPB, ICIPE and Plant Protection Services; State Department of Agriculture.\u00a0 The team has developed a strategy to guide efforts towards management of this new pest.<\/p>\n

Status of Fall Army Worm Spread in Africa<\/strong><\/h4>\n

From the African continent, this pest was first reported in September 2016 in the West Africa region. It has now been reported in Central, Southern and East African regions. In Kenya, FAW infestation was first detected in Trans Nzoia County in the second week of March, 2017 on off-season irrigated maize.<\/p>\n

Spread and Likely Economic Impact of FAW in Kenya<\/strong><\/h4>\n

A field survey conducted in March 2017 and other current reports have confirmed presence of fall army worm in the following counties: Trans Nzoia,\u00a0\u00a0 Bungoma,\u00a0 Kakamega,\u00a0 Uasin\u00a0 Gishu,\u00a0\u00a0 Nandi,\u00a0\u00a0 Kericho,\u00a0\u00a0 Baringo,\u00a0Nakuru and Busia. The pest is causing damage on off-season maize in irrigated areas of these counties. This pest is spreading rapidly and has potential to cause 100% loss in a wide range of crops such as: maize, rice, pasture, sorghum, millet, cotton and some vegetable crops. This will result into national food insecurity and loss of income unless urgent measures are implemented.<\/p>\n

How to Identify FAW<\/strong><\/h4>\n

The fall armyworm caterpillars are green, brown or black in color depending on development stage. A mature caterpillar has a distinct white line between the eyes, which form an inverted \u201cY\u201d pattern on the face <\/strong>(this is seen when the worm is placed facing you). In addition, there are pronounced four black spots <\/strong>aligned in\u00a0 a square <\/strong>on the top of the 8th segment <\/strong>near the back end of the caterpillar. From first to third instar, the caterpillars are small and their initial infestations on crops often go unnoticed.<\/p>\n

FAW Host Range<\/strong><\/h4>\n

This pest mainly attacks cereals: (maize, sorghum, rice, millet, wheat, barley), fodder grasses: (Bermuda grass, Hay grass, and Napier grass), sugar cane and cotton. Others susceptible crop includes: kales, cabbages, legumes\/pulses, banana, tomatoes, capsicum, ginger, spinach, amaranths, onions, sugar beet, citrus, cucumber and sunflower. It can attack over 80 different plants.<\/p>\n

FAW Life Cycle<\/strong><\/p>\n

This pest undergoes complete metamorphosis: eggs- larva- pupa- adult.<\/p>\n

Eggs: <\/strong>The female lays \u2018egg masses\u2019 on the host plant – about 150-200 tiny eggs which are covered with protein sheath to protect from attack by natural enemies and pesticides. In her lifetime, a female lays 1,500-2,000 eggs. Eggs hatch in 2 to7 days depending on weather conditions.<\/p>\n

Larva: <\/strong>The larval stage is the destructive phase feeding on plant soft tissues. Before pupating, caterpillars go through 6 instars with their color changing from light green to dark brown. The upper side of the body<\/p>\n

retains a light color above longitudinal stripes. FAW caterpillars take 2-3 weeks to mature, are 3-4 cm long, and have 8 prolegs with additional pair on last abdominal segment.<\/p>\n

Pupa: <\/strong>The pupa is shiny brown and found underground (2.5 cm -3.7 cm deep) from which an adult emerges in 1-5 weeks depending on soil temperature.<\/p>\n

Adult Moth: <\/strong>are active at night and mates in the evening. The females (1.7mm x 3.8mm) are slightly bigger than the males (1.6mm x3.7mm) in wingspan. The male forewing is mottled; (light brown, grey, straw) while<\/p>\n

Damage Caused by FAW<\/strong><\/h4>\n

The caterpillars feed and damage leaves and inside whorls of young maize plants resulting in small shot holes or large ragged and elongated holes on the plant. Severe feeding gives the appearance of maize that\u00a0 has been damaged by hail. After feeding, FAW caterpillars leave behind large amounts of moist sawdust-like frass near the whorl and upper leaves. FAW infestation cause stunting and destruction of developing tassel and kernels, thereby reducing grain quality and yield.<\/p>\n

Comparison with other Caterpillars<\/strong><\/h4>\n

Infestation by stalk borer is different from FAW damage. The stalk borer caterpillar bores into the stalk\/stem. The FAW caterpillar feed more on peripheral foliage, making larger more ragged holes. They also tend to burrow through the husk instead of feeding down through the silks.<\/p>\n

How FAW is spread<\/strong><\/h4>\n

Long distance introduction of FAW is mainly through great flying capacity of adult moths. In addition, the large number of eggs laid enables the pest to quickly establish in a new area. Movement of infested plant materials; (green or dry stover for animals, green maize cobs) can aid in carrying the different FAW stages within the same farm or in the locality. In Kenya, long distance movement of green maize for roasting is a thriving business, which can contribute to the spread of the pest.<\/p>\n

Implication of fall Ary Worm Infestation<\/strong><\/h4>\n

This pest causes severe damage to plants such as maize, rice, pasture, sorghum, pear millet, cotton and some vegetable crops. This results into economic loss which impacts negatively on national food security and income. So far in Kenya the pest has been noted only on maize. Attack on maize at vegetative stage can result to 100% crop loss if no control is taken. Attack on young maize can totally reduce plant density, warranting re-planting. Infestation on grain in the cob predisposes such to fungal attack.<\/p>\n

Destruction of the silk results to reduced pollination and hence grain formation.\u00a0 In\u00a0 addition,\u00a0 attack on\u00a0 tassels\u00a0 affect pollen provision, which<\/p>\n

reduce fertilization and hence grain formation reduction. The pest has quarantine status in Europe and its presence therefore has implications on international trade. This is critical due to the wide host range.<\/p>\n

Management of FAW<\/strong><\/h4>\n

No studies in the country have been undertaken, therefore, the suggested management options are based on publications from other countries. Strengthening national and county capacity in surveillance, diagnostic skills and management of fall army worm by training public- private extension service providers, seed inspectors, agrochemical dealers, spraying teams, researchers, farmers and the general public is critical to fast track adoption of the following strategies to mitigate against the threat of this new migratory pest:<\/p>\n

1.\u00a0\u00a0 Early Warning<\/strong><\/h5>\n

For\u00a0 detection\u00a0 and\u00a0 early\u00a0 warning\u00a0 mount\u00a0 at\u00a0 least\u00a0 one\u00a0 FAW\u00a0\u00a0 specific pheromone trap per Ha.<\/p>\n

2.\u00a0\u00a0 Monitoring\/Scouting<\/strong><\/h5>\n

Scouting for signs and\u00a0 symptoms of\u00a0 the pest should\u00a0 start one\u00a0\u00a0\u00a0\u00a0 week<\/p>\n

after crop germination.<\/p>\n

3.\u00a0\u00a0 Mechanical Control<\/strong><\/h5>\n