Evaluation of some fungal diseases and yield of groundnut in groundnut-based cropping systems

Impact of intercropping on epidemics of groundnut leaf spots: defining constraints and opportunities through a 7‐year field study

“…These results further support the use of cotton as a desirable intercrop with groundnut. Furthermore, groundnut yield and combined crop yield (as measured by Land Equivalence Ratio, which was not assessed) has been enhanced by intercropping in other studies (Ihejirika et al ., ; Lithourgidis et al ., ), suggesting that additional yield stability might be attained through manipulation of planting date, plant spacing, fertility, or cultivar selection.…”

“…Likewise, Ihejirika et al . () observed a 24% and 36% reduction in ELS of groundnut with maize and melon intercrops, respectively, compared to unsprayed controls. Leaf spot (pathogens undifferentiated) was reduced by intercropping with Atractylodes lancea (Li et al ., ), and both ELS and LLS were significantly reduced by intercropping with pigeon pea in India (Ghewande et al ., ).…”

“…Farrell () observed a reduction in Groundnut rosette virus under intercropping with common bean, and Groundnut bud necrosis virus decreased in intercrops with maize, sorghum and millet, but not other legumes, in studies in India (Gururaj et al ., ; Gopal et al ., ). Groundnut rust was reduced by intercropping with maize and/or melon in Nigeria (Ihejirika et al ., ), and damping off and bacterial wilt incidence were lowered by intercropping with a medicinal plant, Atractylodes lancea , in China (Li et al ., ). Among these studies, only Farrell () evaluated the mechanism by which disease was reduced, finding that aphids vectoring Groundnut rosette virus were trapped on epidermal hairs of intercropped beans.…”

“…Plant diversification has long been employed and advocated as beneficial in agricultural production (Lithourgidis et al, 2011;Zhan et al, 2014;Brooker et al, 2015). Growing two or more crops in close proximity, or intercropping, has been shown to improve water and nutrient use efficiency (Hauggaard-Nielsen et al, 2008;Kn€ orzer et al, 2009;Xiong et al, 2013); insect, disease and weed control (Risch et al, 1983;Ratnadass et al, 2012); resilience to fluctuations in pests, markets and weather (Kn€ orzer et al, 2009;Brooker et al, 2015); and overall yield (Ihejirika et al, 2010;Brooker et al, 2015). A recent literature survey found that intercropping reduced disease severity relative to monocrops in 79% of studies involving fungal pathogens, 72% of studies of virus diseases, 100% of bacterial studies, and 37% of nematode studies (Boudreau, 2013).…”

“…Groundnut (peanut; Arachis hypogea) is a particularly appropriate crop to evaluate: it is a nitrogen-fixing legume cultivated worldwide, it has a history of intercropping, and its pests and diseases are often difficult and expensive to manage (Kokalis-Burelle, 1997). Nutrient enhancements (Xiong et al, 2013), improvement in arthropod communities (Li et al, 2014) and yield and economic advantages (Ghewande et al, 1993;Ihejirika et al, 2010;Singh et al, 2013) have been demonstrated in groundnut mixtures. Farrell (1976) observed a reduction in Groundnut rosette virus under intercropping with common bean, and Groundnut bud necrosis virus decreased in intercrops with maize, sorghum and millet, but not other legumes, in studies in India (Gururaj et al, 2005;Gopal et al, 2010).…”