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B ezuidenhout SR, R einhardt CF & W hitwell MI (2012). Cover crops of oats, stooling rye and three annual ryegrass cultivars influence maize and Cyperus esculentus growth. Weed Research 52, 153-160. Summary No information is available on the effect of cover crops on weed growth in maize production in KwaZulu-Natal, South Africa. In a field experiment, the influence of two preceding cover crops, stooling rye and annual ryegrass, on the growth of maize and the weed Cyperus esculentus were compared with herbicides and weed control by hoeing. Maize emergence and early growth were delayed in the presence of physical residues of both cover crop species, especially annual ryegrass. Growth of C. esculentus was significantly inhibited in the inter-row maize planting lines by the cover crops for the first 16 days after maize emergence, but this effect had diminished by day 28. In a pot experiment, the influence of the same two cover crops on maize and C. esculentus growth was evaluated together with oats and two additional annual ryegrass cultivars. Here, the growth of maize and C. esculentus were suppressed, especially by the root residues of the annual ryegrass, in particular the cultivar Midmar. Chemical analysis of the leachate of the root residues indicated the presence of phenolic acids and benzoxazolin-2(3 H)-one. To achieve effective weed control, a weed management strategy combining the mulch retained on the soil surface, with a possible reduction in the type and amount of herbicide, should be implemented. [ABSTRACT FROM AUTHOR]

Background: The gut microbiome is essential for physiological host responses and development of immune functions. The impact of gut microbiota on blood pressure and systemic vascular function, processes that are determined by immune cell function, is unknown., Methods and Results: Unchallenged germ-free mice (GF) had a dampened systemic T helper cell type 1 skewing compared to conventionally raised (CONV-R) mice. Colonization of GF mice with regular gut microbiota induced lymphoid mRNA transcription of T-box expression in T cells and resulted in mild endothelial dysfunction. Compared to CONV-R mice, angiotensin II (AngII; 1 mg/kg per day for 7 days) infused GF mice showed reduced reactive oxygen species formation in the vasculature, attenuated vascular mRNA expression of monocyte chemoattractant protein 1 (MCP-1), inducible nitric oxide synthase (iNOS) and NADPH oxidase subunit Nox2, as well as a reduced upregulation of retinoic-acid receptor-related orphan receptor gamma t (Rorγt), the signature transcription factor for interleukin (IL)-17 synthesis. This resulted in an attenuated vascular leukocyte adhesion, less infiltration of Ly6G(+) neutrophils and Ly6C(+) monocytes into the aortic vessel wall, protection from kidney inflammation, as well as endothelial dysfunction and attenuation of blood pressure increase in response to AngII. Importantly, cardiac inflammation, fibrosis and systolic dysfunction were attenuated in GF mice, indicating systemic protection from cardiovascular inflammatory stress induced by AngII., Conclusion: Gut microbiota facilitate AngII-induced vascular dysfunction and hypertension, at least in part, by supporting an MCP-1/IL-17 driven vascular immune cell infiltration and inflammation., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)