Research recently published in the Journal of Economic Entomology has offered new insight into managing the tomato leaf miner (Tuta absoluta) using entomopathogenic nematodes (EPN). If the pest is not adequately managed, it can cause up to 100% crop loss in both field and green-house grown tomatoes. Also causing further concern is the increasing insecticide resistance the pest has shown to be developing.
New research by CABI reveals that just five invasive alien species are causing US$0.9 – 1.1 billion in economic losses to smallholder farmers across six eastern African countries each year, equating to 1.8% – 2.2% of total agricultural GDP for the region. These losses are expected to grow to $1.0 – 1.2 billion per year over the next 5-10 years, highlighting the urgent need for coordinated responses at regional, national and international levels. Continue reading
“I have suffered [crop] losses amounting to 90%. I have no other source of income apart from tomato farming. I was relying on this crop to feed my family. I have nothing to do now other than try to think of what to do next.”
Elias Kamuga, Farmer, Kenya
Elias is a smallholder farmer from Kenya. Every year he sells his tomato crop at the local market, which gives him enough money to feed his family. But the arrival of a tomato pest to his region in Kenya has stopped that. The pest – a moth called a tomato leaf miner or Tuta absoluta – was recently introduced to Africa. This pest is an invasive species, and is destroying people’s livelihoods.
In 2015, Elias started to notice his tomatoes were being damaged by this pest. He tried taking them to market, but customers said they had too many holes and spots and were no good. He could not sell his produce. He believes he lost 90% of his tomato crop to the pest, and had no other source of income. Elias tried fighting this tomato pest with chemicals but they did not work. Elias now has to find another way to earn money. Thousands of farmers are in his position.
Invasive species, like Tuta absoluta, are devastating livelihoods. Tomatoes are one of the most widely cultivated crops in sub-Saharan Africa, grown in the backyards of almost every home. This important cash crop and source of nutrition is now being threatened by the recent arrival of the pest.
Tuta absoluta is rapidly moving across the African continent, decimating crops in Egypt, Ethiopia, Kenya and Tanzania. It has recently reached Nigeria, where a state of emergency has been declared – the pest has destroyed an estimated US$5.1 million of tomatoes and forced at least one major tomato processing plant to close. Growers do not know how to control it and many have abandoned tomato farming altogether. The race is on to prevent its spread with management schemes planned to limit its devastation.
Since 2014, CABI helped governments in Africa halt the Tuta absoluta threat and continues to do so. We are currently helping countries like Burundi, Kenya, Nigeria and Tanzania understand how they can best prepare prior to a pest invasion and are delivering practical knowledge on how to manage the pest once it has arrived. To address the recent severe outbreak in Kaduna State, Nigeria, we have provided the government with a technical brief on the tomato leaf miner together with available management experiences to help them develop a control strategy.
In 2015, we launched an important initiative to raise awareness of the threat of invasive species to the livelihoods of the rural poor. Our aim is to draw partners together from around the world to bring pest management solutions that exist already to the people who need them. We included Tuta absoluta as one of the priority targets for coordinated management. Our goal is to protect rural communities in developing countries from the devastating impacts of specific invasive species.
A conversation with Dr Arne Witt
The recent outbreak of Ebola virus disease in West Africa made headline news around the world. During the outbreak this fatal disease, endemic to parts of Central and West Africa, rapidly spread from Guinea, Sierra Leone, and Liberia to other countries in the region such as Nigeria, Mali and Senegal and then further afield to the USA, UK and Spain, mainly through infected health workers. This prompted decisive action from governments around the world and led to the implementation of strict controls at most national points of entry – as a result of this action and increased awareness, the further spread of this disease was effectively halted. No new infections have been reported for a number of months now but the cost has been significant – more than 10,000 people lost their lives, mainly in Guinea, Sierra Leone, and Liberia. However, it is highly probable that without significant interventions the costs could have been far higher. For example, the outbreak of bubonic plague or Black Death in Europe in the 17th century resulted in the death of 34 million people. The accidental introduction of potato blight, a crop disease which affects potatoes, from the Americas to Ireland in the mid-1800s contributed to the starvation of about 1 million people. Rinderpest, a disease affecting livestock was accidentally introduced to Africa from Asia in the late 19th century resulting in the deaths of, it is claimed, a third of the human population of what is now Ethiopia and two-thirds of the Maasai, an ethnic group of pastoralists in East Africa who are totally dependent on livestock. We may ask what Ebola, potato blight and rinderpest have in common – well obviously they have all have had a devastating impact on humanity but what binds them all together is that they are all INVASIVE ALIEN SPECIES (IAS). Fortunately, due to concerted efforts by a range of agencies rinderpest has been eradicated from the planet but as a result of increased trade, travel and tourism more and more species are being moved around the world and many are establishing and are continuing to have devastating impact on livelihoods. Continue reading
Watch a new video illustrating the devastating impacts that Tuta absoluta is having on tomato yields, and what this means for farmers who rely on these crops for sustenance and income.
Dr Arne Witt, from CABI commented on the implications of Tuta absoluta infestation across Africa
“Tomatoes are one of the most widely cultivated crops in Africa and are grown in the backyards of almost every homestead across sub-Saharan Africa. This important cash crop and source of vitamins is now threatened by the recent arrival of the tomato leafminer, Tuta absoluta.
This Invasive Alien Species is rapidly moving down the African continent, having already decimated crops in Egypt, Ethiopia, Kenya and northern Tanzania. Growers are at their wits end as to how best they can control this pest and many have abandoned tomato growing altogether. The race is on to prevent its spread further south with various interventions planned to mitigate its impact in areas where it is already present.”