Effects of intercropping component of conservation agriculture on sorghum yield in the Sudan Savanna

Abstract

Conservation agriculture (CA), which consists of minimum soil disturbance, soil cover, and crop rotation/ association, has been promoted as an indivisible three-component package to control water erosion in the Sudan Savanna. However, CA has not been adopted by local smallholder farmers, probably because the three-component package constitutes a large burden for the farmers. Our previous study revealed that two components-minimum tillage and crop residue mulching-are sufficient for soil conservation and intercropping, when used in combination with minimum tillage and crop residue mulching, had no effect on erosion control. In the present study, we conducted a 3-year field experiment in Burkina Faso to evaluate the effects of the intercropping component on sorghum yield. The four treatments employed were conventional practice (full tillage, no sorghum residue mulching, no intercropping), two-component CA (minimum tillage and sorghum residue mulching without intercropping), and three-component CA with velvet bean (VB) or pigeon pea (PP) intercropping. We found that sorghum yield was similar between treatments during the first 2 years but higher for CA with PP intercropping than for conventional practice in the third year. This increased yield was mainly attributed to higher soil nitrogen and carbon content as well as panicle mass and harvest index observed for CA with PP intercropping than for conventional practice. Unexpectedly, however, PP produced few seeds and did not survive the dry season. Therefore, we concluded that CA with PP intercropping is effective to increase sorghum yield but practical only for the prosperous farmers who can afford to purchase PP seeds every year and accept no increased yield during the first 2 years after its installation. For most smallholder farmers, it would be realistic to promote two-component CA without intercropping because it can effectively control water erosion and reduce the farmers' burden of its adoption in the Sudan Savanna.

Morphophysiological and yield traits of soybean varieties tolerant of intercropping with maize

“…As a result, the seed weight increased. The increasing harvest index, according to Ikazaki et al (2020), could be associated with higher whole plant nitrogen and higher nitrogen translocation efficiency. The increased of dry weight accumulation in the tolerant group compared to the intolerant group indicated that tolerant soybeans have a higher capacity for high dry matter accumulation during harvest.…”

Planting date and tillage effects on yield and nutrient uptake of two sorghum cultivars grown in sub-humid and semi-arid regions in South Africa

“…Summer crop production in South Africa is shifting from current production areas due to changes in rainfall and temperature regimes (Weepener et al, 2014). Sorghum thrives on low fertility soils with limited inputs for food and industrial use in breweries, production of animal feed, and as feedstock for biofuel production (Meki et al, 2013;Ikazaki et al, 2020). Moreover, sorghum is the fifth most important cereal crop after wheat (Triticum aestivum), rice (Oryza sativa), maize (Zea mays) and barley (Hordeum vulgare) (Bakari et al, 2023) with high tolerance to heat and drought.…”