Dr. George Yakubu Mahama, an Agronomist with Council for Scientific and Industrial Research-Savannah Agriculture Research Institute (CSIR-SARI), Wa station, has urged farmers to improve their crop productivity with the adoption of rainwater harvesting techniques.
He said increasing soil water storage and infiltration was a critical component of plant growth and increased yield.
Dr. Mahama said this during a field day in Wa for some farmers in the Wa Municipality and staff of SARI to introduce the participants to the rainwater harvesting technique for improved crop performance.
The CSIR-SARI established the in-situ rainwater collection field trials with financial support from the Linking East and West African farming systems experience into a BELT of sustainable indemnification (EWA-BELT).
The in-situ water collection techniques introduced to the farmers were – tied ridging, furrow sowing, earth and stone bonding, pit planting, and mulch ripping.
Dr. Mahama, the lead researcher on the initiative in the Upper West Region, noted that the trial was to assess the effects of tied ridges in combination with organic (poultry manure) and inorganic amendments on sorghum grain and stover yields.
“The water harvesting techniques evaluated were tied ridges – ridges tied at 1m intervals, ridges tied at 2m intervals, ridges tied at 3m intervals, and ridges (control).
Poultry manure was applied at 5 tons ha-1, inorganic fertilizer (90-60-60 kg ha-1 as NPK), and ½ rate inorganic + ½ rate organic fertilizer”, he explained.
He observed that sorghum productivity in semi-arid areas was primarily limited by low and erratic rainfall in the area and low soil fertility.
He added that soils in those areas had a prevailing light texture and were shallow with low moisture holding capacity hence the need for the farmers to adopt enhanced farming techniques to maximise productivity.
“As a result of the light soil texture and low moisture holding capacity, rainfall in such areas is often accompanied by large amounts of surface runoff.
This runoff can, however, be trapped in situ and become available to crops”, Dr. Mahama indicated.
He encouraged farmers not to only rely on in-situ rainwater harvesting but to also practice good soil nutrient management to increase productivity.
He explained that to address the constraints, combined application of mineral and organic input has been recommended as an appropriate strategy to improve soil fertility and increase crop yields.
Dr. Mahama further noted that the application of inorganic inputs was recognised as a convenient way to rapidly restore nutrient deficiencies in soils.
He, however, observed that for economic reasons, smallholder farmers could not apply the recommended rates of mineral fertilizers.
“The use of manure has become the best way to improve soil properties and increase grain yield of cereals, but the quantities of manure available to smallholder farmers are low”, the Agronomist indicated.