Strict dosing of wheat fertilizer in Mexico
Photo: Sergio Sivamea Cepeda grows wheat and sorghum in Tetabiate, state of Sonora, northwestern Mexico, using zero tillage, crop residues, biofertilizers, and irrigation with wastewater.
In the Yaqui Valley, an irrigated desert in northwest Mexico dedicated to intensive durum wheat cropping, scientists are working urgently with farmers to help them apply nitrogen fertilizer more precisely.
“If you under-apply nitrogen fertilizer, your yield goes down, so farmers typically over-fertilize,” said Iván Ortíz-Monasterio, CIMMYT sustainable intensification and wheat crop management expert.
Wheat plants will use only about a third of the nitrogen applied; the remainder is partly emitted as nitrous oxide, a powerful greenhouse gas, or seeps into waterways, causing harmful algae blooms in the Sea of Cortés off Mexico’s northwest coast.
Ortíz-Monasterio has worked with developers of inexpensive hand-held sensors that let farmers know exactly when to apply fertilizer and how much for optimal crop yield and nitrogen use. Last year, a local company began flying drone-mounted sensors over wheat fields, converting the readings to fertilizer dosage recommendations and selling the information to farmers.
“Farmers growing wheat on approximately 1,000 hectares paid for the service last year,” said Ortíz-Monasterio. “Now four such companies are operating in the Valley. This represents a win-win for local businesses, farmers, and climate change mitigation, not only for Yaqui Valley but potentially for other regions worldwide that share similar growing conditions and challenges.”
Conservation agriculture boosts resilience in small-scale maize farming in Africa
Photo: Zambian farmer Gertrude Banda has benefited from CA practices, including zero tillage, improved weed control, and intercropping maize with cowpeas.
Climate-smart practices are helping smallholder farmers maintain maize yields under increasingly hot and dry conditions in sub-Saharan Africa. The region’s number-one food crop, maize is grown using rainfall and with little or no mineral fertilizer, according to CIMMYT scientist Christian Thierfelder.
“Soil quality is improved by reduced tillage and by rotating or intercropping maize with ‘green manures,’ legumes that add nitrogen and organic matter to the system,” said Thierfelder. “Together with keeping crop residues on the field, these practices build healthier soils, conserve moisture, and allow crops to stand up to erratic weather.”
The residue cover also suppresses weeds and the legume intercrop provides more fodder for livestock, a critical source of income for many farmers. Thierfelder said farmers are requesting more information on climate-smart practices, fertilizer access, improved varieties, and labor-saving techniques.
Drought-tolerant hybrid seed offers farmers reprieve from hunger
Gitau Gichuru, a smallholder farmer in Vyulya, Machakos, Kenya, is not worried about his maize crop, despite the hot sun and dry weather.
For years, prolonged dry spells have undermined the food security and livelihoods of rural families in the region, who depend on rain-fed farming. But Gitau is growing a drought tolerant hybrid developed by CIMMYT and promoted to Kenyan farmers by Dryland Seed company. Under the right management practices, the hybrid can yield up to 20 percent more than other popular drought-tolerant hybrids in the region, according to Dryland Seed’s managing director, Ngila Kimotho.
When Gichuru sowed the hybrid maize for the first-time last season, he didn’t expect the crop to amount to anything. “We only had some little rain at the time of planting and during the vegetative state,” he explained, “but, I’m looking forward to a good harvest.”