The Sunday Mail
Tendai Chara —
THE development of crop varieties better-suited to changing climatic conditions is vital for future food security, experts in the maize seed breeding and marketing industries have said. The recommendations follow weather forecasts indicating Southern Africa faces reduced harvests in the next decade because of climate change.
Extreme weather conditions such as El Nino and La Nina are projected to increase. Experts warn that immediate action must be taken to speed up introduction of new and improved seed varieties. According to researchers, current seed varieties are susceptible to heat stress and drought. Zimbabwe is one of the few Southern African countries to develop new heat stress and drought-tolerant maize seed varieties.
The International Maize and Wheat Improvement Center, known by its Spanish acronym CIMMYT, together with partners under the CGIAR Research Programme on Maize, developed heat stress-tolerant maize varieties. Research by CIMMYT revealed that under experimental conditions, the new varieties doubled maize yields when compared to the yields of commercial varieties.
Also, some of the climate-proof seed varieties are not only tolerant to heat stress and drought, but are also highly nutritious. Pro-vitamin A orange maize varieties were also introduced in the region. Research led by the University of Leeds and published in journal Nature Climate Change journa, states that crop yields will fall in the next decade due to climate change.
Study lead author Professor Andy Challinor, from the Priestly International Centre for Climate at the University of Leeds, wrote: “In Africa, gradually rising temperatures and more droughts and heatwaves caused by climate change will have an impact on maize.
“We looked in particular at the effect of temperature on crop durations, which is the length of time between planting and harvesting. Higher temperatures mean shorter durations and hence less time to accumulate biomass and yield.”
According to the report, it takes anywhere between 10 and 30 years to breed a new crop variety and have it adopted by farmers. In a positive development, Zimbabwe is one of the countries to get climate-proof food crops five years before the anticipated climate change induced effects.
A recent media tour of Zaka and Chiredzi districts, Masvingo province, where CIMMYT conducted on-farm trials for the new climate-proof seed varieties, revealed that the new heat stress and drought-resistant seed varieties were a sure way of combating climate-change induced food shortages.
Mr Karikoga Muromo of Muromo village in Zaka chronicled how the heat stress-resistant varieties brought food security to his household.
“The varieties perform very well in this region when compared to other commercial varieties. From the small demonstration plot, I realised close to 200kgs, which is by far a better yield when compared to other varieties that are not drought and heat-stress resistant,” Mr Muromo said. Some of the new maize varieties will only be on the market during the 2018/2019 agricultural season.
CIMMYT tested the new varieties in Zaka due to the area’s weather conditions. Zaka is a dry area in Natural Region IV and it receives average rainfall of 600mm or less.
With poor soils, the area is characterised by uneven rainfall distribution and high temperatures. Zimbabwe’s poorest communities are hardest-hit by climate change because they are more dependent on their climate-sensitive natural resources and ecosystems; they live in fragile areas that have greater exposure to climate hazards; and are less able to respond to climate change because of limited human, financial, and institutional capacity.
Mr Cosmos Magorokosho, one of the senior scientists at CIMMYT responsible for coming up with climate-resilient maize strains, said, “The new heat stress resistant varieties will without doubt address food insecurity in Africa. Due to the heat and drought-resistant qualities, the new varieties are becoming popular with farmers and seed companies in most parts of Africa.”
The seeds that were used by the Zaka farmers were produced during on-farm trials at the Chiredzi Research Station. Mr Charles Mhazo, head of the Chiredzi Research Station, recommended farmers to use heat stress and drought-tolerant seed varieties.
“We work closely with CIMMYT and in our research, we noted that drought tolerance is very poor in most commercial seed varieties. As such, we are working with CIMMYT in breeding maize for heat and drought – tolerance.
“The varieties produced have proven to be highly successful since they can withstand high temperatures,” Mr Mhazo said. He said the effects of last season’s drought could have been mitigated had the heat- and drought-tolerant maize varieties been introduced on the commercial market.
“If widely adopted, drought and heat tolerant maize could help Zimbabwean farmers cope with extended periods of drought and heat, thereby improving yields, livelihoods and the food security of millions of farmers.”
Farmers, however, bemoaned the unavailability of the new varieties on the market.
“Up to now I don’t know where to get these varieties. I will end up buying the commercial seeds that I know,” said Mr Lovejoy Makonese of Makonese village, Zaka.
This year, a drought induced by El Nino was estimated to have left up to 50 million people in Africa needing food aid. CIMMYT is not alone in its quest to fight climate change induced food shortages. The International Centre for Tropical Agriculture (CIAT) is one of the organisations that are making inroads with regards to tackling climate change through the development of heat stress and drought resistant seed varieties.
Writing in the journal Nature Climate Change, Dr Andy Jarvis, a researcher with CIAT, said: “Investment in agricultural research to develop and disseminate new seed technologies is one of the best investments we can make for climate adaptation.
“Climate funds could be used to help the world’s farmers stay several steps ahead of climate change, with major benefits for global food security.”
The CGIAR Research Programme on Climate Change, Agriculture and Food Security, led by the International Centre for Tropical Agriculture, brings together some of the world’s best researchers in agricultural science, development research, climate science and Earth System science, to identify and address the most important interactions, synergies and tradeoffs between climate change, agriculture and food security.
