30 Aug 2020

Agricultural scientific officer in the Ministry of Agriculture Development and Food Security, Ms Bonolo Lechina-Batoli says Fall Army Worm (FAW) has the potential to wipe out crops and threaten food security if not properly managed.

Presenting on the topic; Tuta Absoluta Management at the just-ended three-day workshop on the management of pests in Botswana, She said the invasive pest ‘could cause significant yield losses if not well managed and had a high potential to affect food security in the country’.

The trans-boundary insect feeds on more than 80 crop plants; particularly maize, which is the most widely grown staple food in sub-Sahara Africa, and it is able to move kilometres per night.

Ms Lechina-Batoli told participants, mostly from the plant protection unit of the ministry, that knowledge of the biology and ecology of FAW informed identification of the link in the life cycle of the pest for the purpose of targeting effective management.

She explained that apart from maize, FAW fed on sorghum and millet, a number of different species of grass, including Napier grass, Guinea grass, and other common grasses, adding that such calls for sound decision making on its management.

Ms Lechina-Batoli said there were key elements in the prevention of the pest such as to plant early and use early maturing or resistant varieties to avoid peak migration of adults.

For other pests, she said if possible, farmers should avoid planting in infested areas while also keeping their fields weed free by removing potential alternate hosts.

In addition, the scientific officer stated that farmers should not move infested maize materials from one area to another to reduce pest spread, but instead graze livestock on them or make silage.

She added that the other key element was to increase plant diversity by using mixed cropping systems such as maize and pumpkin and legumes that include cowpea beans pigeon and peas. 

Presenting on the Citrus Greening Disease (CGD), plant pathologist at the Botswana University of Natural Resources (BUAN), Ms Amogelang Segwagwe explained that the disease was first seen in South Africa in 1929.

She said CGD was a serious disease of citrus and related families that occurred worldwide in the major producing areas of the world.

The disease reduces quality and quantity of citrus, more especially in the Sweet Orange industry as it results in oranges acquiring a bitter taste.

“The fruits are deformed and ripen unevenly, resulting in fruits of poor quality,” she added.

She explained that the disease was prevalent in South Africa, occurring in six out of 10 provinces, adding that the Asian and American type had been detected in countries such as Kenya, Tanzania, Ethiopia, and Yemen, among others.

Ms Segwagwe explained that mitigation measures included adherence to the protocols of the disease as well as producing citrus seedlings in disease-free zone nurseries.

“Citrus seedlings produced in disease-free zone nurseries use shoot-tip grafting to produce seedlings using disease-free mother stock and root stock,” she added.

 The objectives of the workshop was to train participants on the management of pests in Botswana. Ends