icipe press release

icipe Push-Pull technology halts fall armyworm rampage

The fall armyworm is a destructive moth that causes devastating damage to almost 100 plant species, including sorghum, rice, wheat and sugarcane, as well as a variety of horticultural crops, thereby threatening food and nutritional security, trade, household incomes and overall economies. The fall armyworm spreads very fast – in its adult stage it can move over 100 kilometres in a single night. The pest is also capable of laying hundreds of eggs, with the emerging larvae burrowing into crops, destroying and eventually killing the plants.

Until 2016, the fall armyworm was constrained to its native region of origin, the Western Hemisphere (from the United States of America to Argentina). However, in January 2016, the pest was reported in Nigeria and it has since spread at an alarming rate across Africa; its presence has been confirmed in more than 28 African countries, while a further nine either strongly suspect, or are awaiting confirmation of invasion.

Already, in less than two years, the impact of the fall armyworm is being felt across Africa. Estimates from 12 African countries indicate that the pest is causing annual maize losses of between 8 – 21 million tonnes, leading to monetary losses of up to US$ 6.1 billion, while affecting over 300 million people in Africa, who, directly or indirectly, depend on the crop for food and well-being. The pest’s impact is likely to be even higher when its damage on other crops is quantified.

This new menace piles onto a range of existing challenges afflicting Africa. For instance, many regions of the continent are already experiencing the impacts of climate-change, including drier and hotter weather, stressed out soils, various invasive pests such as Tuta absoluta, and increased outbreaks of existing pests such as stemborers and the parasitic Striga weed, leading to enhanced threats to agriculture and health.

“Efforts to control the fall armyworm through conventional methods, such as use of insecticides is complicated by the fact that the adult stage of the pest is most active at night, and the infestation is only detected after damage has been caused to the crop. The pest also has a diverse range of alternative host plants that enables its populations to persist and spread. Moreover, fall armyworm has been shown to develop resistance to some insecticides, while the performance of such chemicals is also hindered by limited knowledge and purchasing power of farmers, resulting into use of low quality, and often harmful products,” notes icipe scientist, Dr Charles Midega.

A recent study has established that a climate-adapted version of Push-Pull, an already widely used technology developed by icipe and partners is effective in controlling the fall armyworm, providing a suitable, accessible, environmentally friendly and cost-effective strategy for management of the pest. These findings represent the first documented report of a readily available technology that can be immediately deployed in different parts of Africa to efficiently manage the fall armyworm.

Push-Pull, an innovative companion cropping technology developed over the past 20 years by icipe in close collaboration with national partners in eastern Africa and Rothamsted Research, United Kingdom, is modelled along the African smallholder farming system of multiple cropping. Originally developed for the control of stemborers, the key pests of cereal crops across most of Africa, and the parasitic Striga weeds, Push-Pull involves intercropping cereal crops with insect repellent legumes in the Desmodium genus, and planting an attractive forage plant such as Napier grass as a border around this intercrop. The intercrop emits a blend of compounds that repel (‘push’) away stemborer moths, while the border plants emit semiochemicals that are attractive (‘pull’) to the pests. Push-Pull has recently been adapted to drier areas through the incorporation of drought tolerant companion plants: Greenleaf Desmodium as an intercrop and Brachiaria cv Mulato as a border crop. In addition, Push-Pull also controls maize ear rots and mycotoxins, while improving soil health and providing high quality fodder, since the companion crops are superior forages. Therefore, the technology facilitates crop-livestock integration thus expanding farmers’ income streams.

“Over the past several months we received information from Push-Pull farmers that their fields were free of fall armyworm infestation while neighbouring monocrop plots were being ravaged by the pest. Therefore, we evaluated the climate-adapted version of the technology as a potential management tool for fall armyworm in Kenya, Uganda and Tanzania,” explains Prof. Zeyaur Khan, Push-Pull leader at icipe.

The study revealed fall armyworm infestation to be more than 80% lower in plots where the climate-adapted Push-Pull is being used, with associated increases in grain yields, in comparison to monocrop plots. The findings were supported by farmers’ perceptions through their own observations regarding significantly reduced presence of fall armyworm in Push-Pull plots.

“The ability to manage such a devastating pest clearly demonstrates Push-Pull’s utility as a platform technology in addressing the multitude of challenges that affect cereal-livestock farming systems in Africa. icipe intends to continue disseminating the technology as widely as possible across Africa, while advancing studies to understand the scientific basis of its effectiveness against the fall army worm,” says icipe Director General, Dr Segenet Kelemu.

Dr Kelemu further acknowledges the long term and dedicated investment by various donors including: the European Union; Biovision Foundation for Ecological Development, Switzerland; UK’s Department for International Development (DFID); Swedish International Development Cooperation Agency (SIDA); the Swiss Agency for Development and Cooperation (SDC); the Kenyan Government, and several others, in the development and implementation of Push-Pull, as a clear example that investment in research for development pays and generates high value for money.

Notes for Editors

icipe’s mission is to help alleviate poverty, ensure food security, and improve the overall health status of peoples of the tropics, by developing and extending management tools and strategies for harmful and useful arthropods, while preserving the natural resource base through research and capacity building.

The Push-Pull technology involves intercropping cereals with a pest repellent plant, such as Desmodium, which drives away or deters stemborers from the target food crop. An attractant trap plant, for instance, Napier grass (Pennisetum purpureum), is planted around the border of this intercrop, to attract and trap the pests. As a result, the food crop is protected from the pests. In addition, Desmodium (D. uncinatum or D. intortum) stimulates suicidal germination of Striga and inhibits its attachment to the roots of cereal crops by hindering growth of its haustorium. Moreover, Desmodium improves soil nitrogen, phosphorous, carbon and biodiversity. The technology has also been noted to reduce aflatoxin contamination, and more recently, the fall armyworm that has invaded several African countries. Push–Pull also has significant benefits for dairy farming, since Desmodium and Napier or Brachiaria grass are high quality animal fodder plants. Therefore, Push-Pull improves household nutrition, incomes and overall livelihoods.

Publication details: Midega CAO; Pittchar JO; Pickett JA; Hailu GW; Khan ZR (2017) A climate-adapted push-pull system effectively controls fall armyworm, Spodoptera frugiperda (J E Smith), in maize in East Africa. Crop Protection. Available at http://www.sciencedirect.com/science/article/pii/S0261219417303216

Financial support for this research was provided to icipe by: European Union; Biovision Foundation for Ecological Development, Switzerland; UK’s Department for International Development (DFID); Swedish International Development Cooperation Agency; the Swiss Agency for Development and Cooperation (SDC); and the Kenyan Government. The views expressed herein do not necessarily reflect the official opinion of these donors.

Collaborators: The studies were conducted in collaboration with Rothamsted Research, UK, which receives grant-aided support from the Biotechnology and Biological Sciences Research Council (BBSRC), UK, with additional funding provided under the Biological Interactions in the Root Environment (BIRE) initiative.

Corresponding author: Dr Charles Midega, Email: cmidega@icipe.org


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tuta larva on tomato (2)

The South American tomato leaf miner, Tuta absoluta was first reported from Madhya Pradesh and the Punjab, India in two recent publications.

Report on the occurrence of South American tomato moth, Tuta absoluta in Punjab, India as evident from trap catches and molecular diagnosis. Pest Mgt. in Horticultural Systems 23:89-91 (2017).

First report of South American tomato leaf miner, Tuta absoluta from Madhya Pradesh, India. Pest Mgt. in Horticultural Systems 23:92-93 (2017).

With the presence of Tuta absoluta in the Punjab, if it has not already done so, it is expected to invade Pakistan in the near future.

Development of Low Cadmium Elite Indica Rice Cultivars via CRISPR-Cas9

Rice grain with excessive cadmium (Cd) is a serious threat to health for people who consume rice as a staple food. However, the development of elite rice cultivars with consistently low Cd content is challenging for conventional breeding approaches. Hunan Hybrid Rice Research Center researchers reported the development of new indica rice lines with low Cd accumulation and no transgenes. The team knocked-out the metal transporter gene OsNramp5 using the CRISPR-Cas9 system.

Analysis of the new indica lines showed that Cd concentrations in shoots and roots of the developed mutants were greatly decreased. Furthermore, Cd-contaminated paddy field trials also showed that Cd concentration in the grains of the CRISPR-developed lines was consistently less than 0.05 mg/kg. The plant yield was also not significantly affected in the developed mutants.

This study presents a practical approach to developing low cadmium indica rice cultivars that minimizes contamination risk in grains.

For more information, read the article in Scientific Reports.


fresh fruit logoffp

The same Australian university that is trialing Vitamin A-enriched bananas in Uganda has successfully developed genetically modified Cavendish bananas with resistance to the deadly soil-borne fungus Panama Disease Tropical Race IV.

In their world-first GM field trial conducted in heavily TR4-infested soil, Queensland University of Technology (QUT) researchers found one Cavendish line – transformed with a gene taken from a wild banana – was completely free of the disease.

In addition, three others from the six lines tested also showed showed robust resistance, which is very exciting according to project lead Professor James Dale from QUT’s Centre for Tropical Crops and Biocommodities.

The results have just been published in Nature Communications.

Click here for a feature article we published back in 2013 with Dr Dale discussing his vision for improved nutrition and disease resistance through GMO bananas.

The field trial ran from 2012 to 2015 on a commercial banana plantation outside Humpty Doo in the Northern Territory previously affected by TR4. The soil was also heavily reinfested with disease for the trial.

Professor Dale said the outcome was a major step towards protecting the US$12 billion Cavendish global export business, which is under serious threat from virulent TR4.

“These results are very exciting because it means we have a solution that can be used for controlling this disease,” he said.

“We have a Cavendish banana that is resistant to this fungus that could be deployed, after deregulation, for growing in soils that have been infested with TR4.







“TR4 can remain in the soil for more than 40 years and there is no effective chemical control for it. It is a huge problem. It has devastated Cavendish plantations in many parts of the world and it is spreading rapidly across Asia. “It is a very significant threat to commercial banana production worldwide.”

They will have the capacity to grow up to 9,000 plants and quantify crop yield over the five-year trial.

“The aim is to select the best Grand Nain line and the best Williams line to take through to commercial release,” Professor Dale said. “While in Australia we primarily grow Williams, in other parts of the world Grand Nain is very popular.”

Professor Dale said the correlation demonstrated between the RGA2 gene activity and TR4 resistance opened up new research. 

“We can’t make the assertion that the RGA2 gene is the gene responsible for the resistance in the original wild diploid banana, because in the modified Cavendish we significantly increased the gene’s expression –  the level of its activity – over its activity in the wild banana,” he said.

“But we’ve established a correlation, and we’ve found that the RGA2 gene occurs naturally in Cavendish – it just isn’t very active.

“We are aiming to find a way to switch that gene on in the Cavendish through gene editing. We’ve started that project. It is not easy, it’s a complex process that is a way off, with four or five years of lab work.

“We’re also looking at as many genes as possible in the wild banana and screening them to identify other resistance genes, not only for resistance to TR4 but to other diseases.”

Other key findings of the field trial:

  • Nine lines of Cavendish Grand Nain transformed with the nematode-derived Ced9 gene were also trialled, with one line remaining TR4-free for the three years
  • There was no difference in observed mature bunch size between the transgenic bananas and healthy control Cavendish

The article, Transgenic Cavendish bananas with resistance to Fusarium wilt tropical race 4, can be accessed here.



IPM IL Logo                             iapps-logo4

The 22nd Meeting and Scientific Conference was held in Wad Medani, Sudan from 23 – 28 October 2017. There were about 250 participants from Sudan, Ethiopia, Kenya, Tanzania, Malawi, Tanzania, Ghana, Senegal, Cameroon, DR Congo, Ivory Coast, Uganda, Burkina Faso, Benin, and the U.S.A. Prof. R. Muniappan, Director, IPM Innovation Lab represented IAPPS and presented a keynote address entitled, “Management of Invasive Mealybugs”.  Participants visited Gazira Scheme, about 800,000 hectares of canal-irrigated area where corn, sorghum, cotton, sugarcane and vegetables are grown.

The cotton mealybug, Phenacoccus solenopsis, previously causing severe damage and crop loss is currently under control by the fortuitously introduced parasitoid, Aenasius arizonensis. The cotton leafhopper, Jacobiasca lybica (=Empoasca lybica) has been causing hopper burn symptoms on the Bt cotton grown in this area.

AAIS scientists in cotton MG_4020

AAIS meeting participants visiting cotton production area in the Gazira Scheme, Sudan

IPM IL Logotuta larva on tomato (2)iapps-logo3

The 12th Arab Congress of Plant Protection was held in Hurghada, Egypt, from November 4-10, 2017. There were about 300 participants from Egypt, Syria, Lebanon, Jordan, Sudan, Tunisia, Algeria, Morocco, Pakistan, Italy, and the U.S.A. Participating regional and international organizations were FAO, EPPO, CIMMYT, ICARDA and CIHEAM. Prof. R. Muniappan, Director, IPM Innovation Lab, representing IAPPS in this congress,              presented a keynote address entitled, “Building Bridges between Plant Protection Disciplines for Sustainable Crop Protection”. Key symposia included the South American tomato leafminer, Tuta absoluta.

ARab cong tuta sym particpants

Participants in the South American tomato leafminer, Tuta absoluta, symposium.



Via PestNet

hindu 2


ICRISAT researchers make peanuts free of aflatoxin

R Prasad

Dual strategy involves inserting 2 alfalfa genes into the plants to boost immunity and gene silencing technique to prevent any toxin production

Researchers at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Hyderabad have developed dual strategies to keep groundnuts almost free of aflatoxin — a toxin produced by the fungi Aspergillus flavus and Aspergillus parasiticus — contamination. While one strategy prevents groundnuts from being infected by the fungus thereby preventing the toxins from being produced, the other strategy prevents the fungus from producing the toxin even if groundnuts somehow get infected with the fungus.

Genetic engineering approaches were used for inserting two alfalfa genes into groundnut plants to enhance immunity against fungal infection and growth. Preventing aflatoxin production even in case of any infection was achieved through a plant-induced gene silencing technique.

While both strategies showed promising results, the ultimate goal is to combine the two traits into a single variety to offer double protection so that groundnuts do not accumulate any aflatoxin or the amount of toxin is well within permissible limits at or after harvest.

Combining the two traits

“It is a proof-of-concept study. We have individually tested each of the two mechanisms and it is a matter of using conventional plant breeding approaches to develop a variety that has both the traits in place,” says Kiran K. Sharma from ICRISAT.

The researchers plan to start field trials early next year. “It will take one-two years to breed the two traits into a single variety and another about three years to conduct biosafety trials followed by the development of regionally adapted groundnut varieties. So, if everything goes to plan and gets approved by the Genetic Engineering Appraisal Committee (GEAC), farmers will have a groundnut variety that is near-immune to aflatoxin contamination in five to seven years,” says Dr. Pooja Bhatnagar-Mathur from ICRISAT who led the team.

“We selected two specific genes from alfalfa and inserted them into groundnut plants to enhance the immunity against fungal infection and growth. Groundnuts showed very little fungal infection and negligible aflatoxin contamination,” says Dr. Bhatnagar-Mathur. “We choose alfalfa as it is a legume like groundnut.”

To further prevent toxin production even when groundnuts get infected with the fungus, the researchers designed two small RNA molecules that silence the fungal genes which produce aflatoxin.

“When the fungus and plant come in contact with each other the small RNA molecules from the plant enter the fungus and prevent it from producing aflatoxin,” says Mr. Sharma, who is the first author of the paper published in Plant Biotechnology Journal.

About 40 hours after infection with Aspergillus, six lines with alfalfa genes showed less than 1 part per billion (ppb) of toxin and another five lines showed 1-4 ppb compared with over 3,000 ppb in groundnuts that did not have these genes. Similarly, six lines carrying the RNA molecules, the toxin present was less than 1 ppb and two other lines showed 1-4 ppb of toxin. “It is much lower than the Indian and U.S. safety limit of 20 ppb and meets even the stringent European safety limit of 4 ppb,” Dr. Bhatnagar-Mathur says.