Compiled by:E. Cheramgoi

Editorial and publication coordinated by:Knowledge, Information and Outreach Unit

KALRO Information Brochure Series 2017/030

Kshs. 30

COMMON PESTS OF TEA IN KENYA

iii. Spray pyrethrum based synthetic pyrethroidpesticides, which have low pre-harvest period (lessthan 48 hours) and are effective at low rates.

5.Aphid (Toxoptera aurantii)Symptoms: Brown aphids are found in large numbers onthe youngest shoots and on the underside of leaves. Theaffected leaves curl backwards.Prevention / Control

i. Reduce the plucking interval and or hard plucking

Cupped, cracked and brown margins

Aphids on Tea

till the population goes down. With on-set of rains, the population will down

ii. Spray pyrethrum based synthetic pyrethroidpesticides, which have very low pre-harvest period(less than 48 hours) and are effective at low rates.

iii. Syrphid flies occurring naturally in tea fields alsoplay a large role in their control.

6. Tea weevilsSymptoms: Girdles the stem just above the ground,also feeds on the bark of twigs and tea branches.Generally adults eat the leaf margins causing notch-likeindentations.Dissemination of pest and disease management

packages and services

Tea weevil and damage

1. Pest and Disease surveillance, Reports and Trainings

2. Advisory visits / visits by clients3. Laboratory analysis of Samples4. Publications:-

i) Quarterly Bulletinii) Annual Reportiii) Tea Journaliv) Tea Growers Handbookv) Pest and disease Handbook

For Further Information, Contact:The Institute Director

Tea Research InstituteP. O. Box 820, 20200, Kericho

Tel. (052) 2020598/9; 0722209915E-mail: info@tearesearch.or.ke

IntroductionPests of tea in Kenya often cause serious damage resulting in economic losses. Tea mites increase particularly during the dry season and subside in the wet months. High infestation result in serious defoliation and delayed recovery from drought. Tea mites are common pests in the regions east of rift valley while Helopeltis spp. and termites are common in the West of rift valley.

Common Pests1. Tea mites

i. Red crevice mitesii. Red spider mitesiii. Purple mites

2. Fried egg scales3. Mosquito bug (Helopeltis sp.)4. Mole rats and Porcupines5. Yellow tea thrips6. Termites

Symptoms and Management strategies of Common Pests

1.Tea mitesSymptoms: Generally, affected leaves turn brown,premature leaf fall occurs, during severe drought, youngleaves are attacked.

Red crevice mite

Prevention / Controli. Use adequate / recommended tea nutritionii. Plant resistant clonesiii. Pruning crop to disrupt pest built up.

2. Fried egg scalesSymptoms: These insects are found on mid-ribs andboth upper and lower surfaces of leaves and are softgreen, soft brown or fried egg-like. Sometimes leavesturn black with sooty moulds.

iv. The natural enemies contribute up to about 10%

control.

3. Mosquito bug (Helopeltis spp.)Symptoms: manifest as dark brown spots on the young shoots, which turn black and produce distortions on leaf and stems as the growing tissue expands.Prevention / Control

Red spider mite

Purple mite

Purple mite

Fried egg scales

Mosquito bug and damage

i. Establish strong and healthy tea bushes that areweed free, and practice adequate plucking ofplants.

ii. Spray pyrethrum based synthetic pyrethroidpesticides which have low pre-harvest period (lessthan 48 hours) and are effective at low rates.

iii. Use resistant clonesiv. Clear bushy areas adjacent to the affected site

4. Mole rats and PorcupinesSymptoms: Damage tea by feeding on roots resulting incomplete destruction of plants.

Prevention / Controli. Trappingii. Control weeds, particularly grass, along the edges

of the farm.iii. Fumigation with Detia / Phostoxin

Yellow tea thripsSymptoms: Young leaves are stunted, cupped with cracked and browning margins.

Prevention / Controli. Reduce plucking interval and or hard plucking till

the population goes downii. Heavy rains also reduce their population.

Prevention /Controli. Prune plants when dueii. Plant resistant clonesiii. Use petroleum oil sprays (it is not an insecticide)

are safe on natural enemies (parasitic wasp)