Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM) fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole c...

Despite the resurgence of parastatal marketing boards and strategic grain reserves over the last decade in eastern and southern Africa, there is little empirical evidence about how their activities affect smallholder input use and cropping decisions. This paper uses panel survey data from 1997-2007 on Kenyan smallholders to investigate the effect of Kenya’s National Cereal Produce Board activit...

We present two pieces of evidence that regulation of cytoplasmic pH near neutrality is a prerequisite for survival of root tips during hypoxia. First, blackeye peas and navy beans show earlier cytoplasmic acidosis under hypoxia than soybeans or pumpkin or maize, and die earlier. Second, when cytoplasmic acidosis in maize root tips is greatly retarded by treatment with 25 millimolar Ca(NO(3))(2)...

Intercropping, which grows at least two crop species on the same pieces of land at the same time, can increase grain yields greatly. Legume-grass intercrops are known to overyield because of legume nitrogen fixation. However, many agricultural soils are deficient in phosphorus. Here we show that a new mechanism of overyielding, in which phosphorus mobilized by one crop species increases the gro...

Sustainability of maize-based cropping systems is a major challenge for southern Africa, yet the demand for maize as staple food and animal feed in the region continues to increase. A study was conducted on a sandy clay loam (220 g clay kg-1 soil) at Domboshawa in Zimbabwe to investigate the long-term effects of organic resource quality and application rate, and nitrogen (N) fertilization on so...

Fermented maize product, ogi, is a popular weaning and breakfast cereal in west coasts of Africa. In the study proximate, mineral and amino acid compositions of ogi from a composite mixture of white maize (Zea mays L.) and scarlet runner bean (Phaseolus coccineus L.) flours were evaluated using standard processing techniques. Maize ogi was substituted with scarlet runner bean flour at ratios of...

Chromatographically distinct isoacceptors of leucyl-tRNA from mature bean leaves were all observed to hybridize with bean chloroplast and nuclear DNA in a ratio similar to that exhibited by the unfractionated leucyl-tRNA. Under the same hybridization conditions, maize tRNA failed to form a stable hybrid with bean DNA, and levels of hybridization between bean-leaf leucyl-tRNA and nuclear or chlo...

Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (...

Wang Shengfeng,Xu Jianxin,Yang Shuqin,Jia ping (North China University of Water Resources and Electric Power, Zhenzhou, P. R. China) Email:[email protected] Abstract:Winter wheat and summer maize were important grain crops in China,and winter wheat-summer maize continuous cropping was the main tillage method in north China.According to field experiment datas, Jensen models of winter wheat and...