THE BIOLOGY AND ECONOMIC IMPORTANCE OF THE MANGO WEEVIL IN THE COAST PROVINCE OF KENYA

Mango was first introduced to the coast of Kenya in the 16th century by the Portuguese traders.
At present it is a major crop in the Coast Province of Kenya, occupying nearly 9,000 hectares.
Most of these mangoes are exported to the Middle East and the United Kingdom.
One of the major problems in mango production in all mango-growing areas in the world is infestation by the mango weevil, Sternochetus mangiferae.

Studies carried out at the Coast Agricultural Research Station revealed that over 50% of mangoes form the Coast Province were infested by mango weevil.
Percentage damage varied considerably in different cultivars.
Among the approved cultivars Apple had the highest infestation at 68%, while infestation on Boribo and Ngowe was 45 and 25% respectively.

A female weevil laid an average of 262 eggs and the oviposition period was 62 days.
A maximum of 18 eggs were laid per day.
The eggs were laid on the skin of the fruit and took seven days to hatch.
The larva penetrated through the flesh of the fruit into the seed.
The development of larva, pupa and transformation into adult weevil took place within the seed.
The larval and pupal stages took 22.5 and 8 days, respectively.
Adults emerged by tunelling a hole through the seed.
Fed and non-fed adults survived an average of 90 and 65 days respectively.
No alternative host was recorded.

IX African Symposium on Horticultural Crops

K. Mwangi

https://doi.org/10.17660/ActaHortic.1985.153.33