Small holder farmers in high density areas of Kenya can now heave a sigh of relief. That is after a recent study confirmed that their “new maize planting strategy” – can after all alleviate feed shortages by ensuring a constant supply of fodder for livestock without compromising grain quality and quantity.
Led by ILRI scientist, Ben A. Lukuyu, the study put scientific confidence to the practice of planting maize densely and thinning it for fodder as the need arises in an effort to increase forage. Lukuyu’s study titled Integrated maize management options to improve forage yield and quality on smallholder farms in Kenya has confirmed that the grain yield remains uncompromised.
Lukuyu et al observe that maize is an important crop for maize-dairy farmers in Kenya and is useful both as grain and as fodder. However, the dual problems of small farm size on the one hand and the maize streak virus disease (MSVD) on the other hand, undermine the fodder and grain the farmer harvests leading to shortages of both in the dry season.
As a result, farmers on their own volition changed their maize management practices by planting densely and systematically thinning the crop to obtain both fodder and grain. They perceived MSVD to have the greatest effect on forage yields and to be a difficult disease to control.
Scientific research by Lukuyu’s team quantified for the first time the impact of MSVD on thinnings and stover. They used data from participatory on-farm research on cultural management practices of maize and on-station field trials in which plants were artificially infected with maize streak virus disease (MSVD) in the intensive maize–dairy production systems in central Kenya. They ensured that forage yields of the susceptible maize varieties were reduced more than for the resistant varieties.
The study concluded that planting density increases forage yields without negatively affecting grain yields if thinning is managed according to the crop situation or need for forage. There also might be tradeoffs between breeding for MSVD resistance and fodder quality in terms of quantity and quality of forage (thinnings and stover).
The maize management trials showed that increasing plant density increased forage yields by up to 41% but decreased grain yields by up to 17% when specific thinning regimes were applied fairly late in the growth of the crop. However, grain yields were maintained when maize was planted at high density and then progressively thinned for forage during the growing season according to the crop situation or need for forage.
The on-station research is the first study on the impacts of MSVD on maize forage. It was carried out to increase production of forage during the wet seasons with a view to mitigating forage shortages during the dry seasons. MSVD infection was achieved with artificially infected leafhoppers (Cicadulina mbila (Naudé) (Hem.: Cicadellidae).
The paper available online 8 July 2013 from ScienceDirect in the journal Field Crops Research.
By Jane Gitau