Online Reporter
Sifelani Tsiko, Innovations Editor
Confined field trials of Bt cotton at five sites in Zimbabwe show positive results, giving more scope for the country to scale up production of white gold, which has been declining for years, according to Dr Karim Traore, regulatory manager Traited Seeds and Africa Co-ordination for Bayer Crop Science.
Speaking at a workshop on sharing results for confined field trials conducted using Bollgard II cotton, he said the outcome of trials conducted at Kadoma Cotton Research Institution, Save Valley Experiment Station, Chiredzi Research Station, Panmure Shamva Experiment Station and Chisumbanje Experiment Station were quite encouraging.
“Bayer Zimbabwe managed to secure two permits from the National Biotechnology Authority for confined field trials with the Genetically Modified cotton MON 15985 (Bollgard®? II) at five sites in Zimbabwe,” Dr Traore said.
“The results are positive and there is great scope to move to the commercialisation stage once the authorities approve this. We got a one year permit for the 2022-2023 cropping season and another for the 2023-2024 season.”
Dr Traore said the results were positive and showed that Bt cotton could help farmers decrease their insecticide use and incur costs, time, and labour savings.
Furthermore, he said, farmers will be less exposed to toxic chemicals, reducing risks to their health and to the environment.
University of Zimbabwe Dean of the Faculty of Science, Professor Idah Sithole-Niang said genetically modified cotton is developed using bacterium Bacillus thuringiensis (Bt), which naturally produces a chemical harmful only to a small fraction of insects such as the bollworm.
The Bt toxin is inserted into cotton, causing cotton called Bt cotton, to produce this natural insecticide in its tissues.
She said Bt cotton can help reduce heavy reliance on pesticides and reduce input costs for farmers.
“The gene that has been introduced comes from the soil bacterium Bacillus thuringiensis, or Bt for short,” Prof Sithole- Niang said.
“The toxin, which is itself a protein, binds to specific cells in the lining of the guts of the susceptible larvae, punctures them, and leads to the death of the larvae.
“Farmers can achieve higher yields and reduce exposure to chemicals significantly. In addition, they can get improved cotton yields as damage by bollworms is reduced significantly. The benefits are there for Bt cotton and we should not hesitate to tap on the benefits that come with this technology.”
The Bt cotton field trials were conducted at five locations in various regions of the country.
Bt cotton plants were grown alongside non-Bt cotton plants and Dr Traore said the non-Bt cotton plants were sprayed with insecticide three times, while the Bt cotton plants were sprayed only once.
“Bt hybrids exhibited the lowest incidence of Lepidopteran pests, approximately two times lower than that of open pollinated varieties (OPVs) and three times lower than non-Bt hybrids,” he said.
“On average, Bt hybrids required one spray, while non-Bt hybrids needed three sprays and OPVs required two sprays. Bt hybrids experienced the least locule damage, compared to non-Bt hybrids and OPVs.”
He said the National Biotechnology Authority of Zimbabwe must consider the field trial data and the robust history of safe cultivation of MON 15985 cotton around the globe as sufficient supporting evidence for authorising a general release of MON 15985 cotton as a tool to control bollworms for cotton production in Zimbabwe.
Zimbabwe has taken a precautionary approach towards risk regulation of GMO products and technologies as reflected and reinforced by the adoption of the National Biotechnology Authority Act of 2006.
Even though the country still maintains a ban on the commercial release of GM crops due to health and environmental safety concerns, it has agreed to allow researchers to conduct trials for GM cotton which is resistant to bollworms.
More than 90 percent of cotton grown in the main cotton producing countries (US, India, and China) is now genetically-modified (GMO).
Cotton farmers in Africa suffer huge losses due to pest problems. The most destructive of pests is the African bollworm (Helicoverpa armigera), which biotech experts say in severe cases can cause a 100 percent loss while in unprotected fields pest damage can be as high as 90 percent.
Prof Sithole-Niang said adopting Bt cotton can help reduce input costs and control damage from bollworms and other insects that frequently damage cotton.
Cotton is a major cash crop for more than 200 000 smallholder farmers in Zimbabwe and it generates employment in farm, ginning and processing activities.
This sector contributes about 3,5 percent to the Gross Domestic Product, earning the country between US$80 million and US$100 million per year.
In 2024, Zimbabwe’s cotton season ended with an estimated 13 000 tonnes delivered by farmers, the lowest known production record due to the devastating impact of the El Niño-induced drought.
This figure was significantly lower than the 82 000 tonnes delivered by farmers in 2023 and far below 42 000 tonnes the Government had projected.
An official of Mahyco, a company which acquired a 60 percent stake in Quton Seed Company (Pvt) Ltd, said the Mahyco Cotton Hybrids in Bollgard2 Technology has in-built protection against bollworms and is likely to give significant yield advantage.
“This cotton hybrid seed variety can lead to huge spray savings for bollworm control and has a potential to give an incremental income of US$400 per hectare or more in good management conditions,” he said.
“At 100 000 ha adoption, it can have an incremental US$$40 million farmer income and this could have added benefits of incremental US$65 million forex income to the country and create employment for 10 000 seed grower farmers.”
The Quton official said Bt cotton can increase yields per hectare and bring higher income for farmers, ginners and the cotton value chain while saving on crop protection costs. Cotton is a vital crop that supports the livelihoods of thousands of smallholder farmers.
“Our cotton industry faces numerous challenges, including low yields, pests and diseases. This is where biotechnology can be harnessed to solve such challenges,” said Permanent Secretary in the Ministry of Higher and Tertiary Education, Innovation, Science and Technology Development, Professor Fanuel Tagwira.
“Scientific and technological advancements must be harnessed to improve our agriculture. It is essential to explore a range of innovations that have the potential to contribute to improved productivity, resilience and sustainability.”
Prof Obert Jiri, the Permanent Secretary in the Ministry of Lands, Agriculture, Water, Fisheries and Rural Development said cotton is a strategic crop for the country that has been facing the persistent challenge of bollworm infestation. This challenge, he said, had led to the heavy reliance of chemical pesticides increasing production costs and environmental risks.
“The Bollgard II cotton trials were conducted to find out whether the technology could proffer solutions for our current challenges,” he said.
“These trials are a testament to our dedication to exploring innovative agricultural practices that can potentially enhance the productivity and sustainability of our cotton industry. At the heart of our agricultural policy is the openness to embracing new practices and innovations.”
Although the confined field trials showed positive results, necessary procedures still need to be taken before Bt cotton can be commercialised in the country.
“The results from these confined field trials provide evidence for considering the adoption of Bollgard II cotton in Zimbabwe,” Prof Jiri said.
“However, before full commercialisation, it is imperative that we engage key stakeholders including farmers, researchers, policymakers and industry players for informed decision making.”
The Attorney-General’s Office is finalising the Genetically Modified Organism regulations and a decision on whether to commercialise Bollgard II cotton will be made after the regulations have been gazetted.
“The process should involve careful consultations with various stakeholders, ensuring that the final decision made by the NBA board balances scientific advancements with safety, ethical considerations and national interests,” said Prof Tagwira.
